# European_Red_List_2017_December

taxonomicNotes:
See Smith (1991) and Wallace (1967). This species is often confused with Myliobatus aquila.

redListCategoryRationale:
European regional assessment: Critically Endangered (CR) Bullray (Pteromylaeus bovinus) is considered widespread in the Northeast Atlantic and Mediterranean Sea, but there are few records. It can be inferred from available knowledge of other myliobatid rays that this species is susceptible to a range of inshore fishing gears and has a sensitive life history with a low fecundity (three to four pups per litter). In some areas of the eastern Atlantic and Mediterranean Sea fishing pressure is intense and unregulated throughout its range. A population reduction of at least 80% over three generations (45 years) is suspected based on its shallow depth range, slow life history, high catchability and paucity of records. Bullray is therefore assessed as Critically Endangered in the European region under Criteria A2c.

range:
In the Northeast Atlantic, this species occurs along the Iberian Peninsula, northwards to the southern Bay of Biscay, and southwards to the Eastern Central Atlantic, off Morocco and Madeira, but not around the Azores, and south towards western Africa. It also occurs throughout the Mediterranean Sea, but not in the Black Sea (Ebert and Stehmann 2013). The depth range is between the surf zone and depths of 30 m.

population:
This species was not caught in a trawl survey of the entire northern Mediterranean basin between 1994 and 1999 conducted as part of the International Trawl Survey in the Mediterranean (MEDITS) programme (Baino et al. 2001). Similarly, Damalas and Vassilopoulou (2011) found none during trawl surveys in the Aegean Sea from 1995 to 2006. Only one specimen in 1948 was caught in scientific trawl surveys conducted in the Adriatic Sea between 1948 and 2005 (Ferretti et al. 2013). However, in recent years others have reported small numbers of this species in the northern Mediterranean Sea, including Puerto de Mazarrón off southeastern Spain (Hernández-Orts et al. 2010), the southeast Aegean Sea (Corsini-Foka 2009), the eastern Ionian Sea (Zogaris and Dussling 2010), and Iskenderun Bay off Turkey (Bausta et al. 2012), which suggests it still occurs in this region. Furthermore, capture of pregnant females in the northern Adriatic Sea suggests this species is reproducing in the area (Dulcic et al. 2008).Nothing is known of population size or temporal trends in population abundance in the Northeast Atlantic or Mediterranean Sea, except that it appears to be extremely rare. It can however be inferred from the status of similar myliobatid rays that this species is likely decreasing as a result of overfishing throughout its European range, and a population reduction of at least 80% over three generations (45 years) is suspected.

habitat:
This benthic and semi- to epipelagic species occurs in tropical to warm temperate coastal waters between the surf zone and depths of 30 m, and sometimes also farther offshore. It also occurs in shallow bays, lagoons and estuaries where salinity is low (Ebert and Stehmann 2013).In the northern Adriatic Sea, Dulcic et al. (2008) found pregnant females bearing near-term embryos, ranging between 37 and 45 cm disc width (DW) and weighing 740−1,080 g. Some of the mature specimens were among the largest recorded to date, at 154−222 cm DW and 68−116 kg total weight. Similarly, Lipej et al. (2008) reported maximum DWs of 113.5 cm (male) and 222 cm (female) from the northern Adriatic Sea. The maximum total length recorded was a 294 cm female.Its generation length is inferred to be around 15 years, based on the fact that the related species Rhinoptera marginata (another member of the Myliobatidae family that also occurs in Mediterranean waters) has a generation length of around 11 years (Neer and Thompson 2005).

threats:
Little information is available on catches outside of South Africa, but given the species’ inshore occurrence, it is likely taken in coastal artisanal fisheries across much of its range. Another threat likely affecting this species is habitat degradation from human activities in the coastal zone (e.g., land development and pollution). Activities in the coastal zone and adjacent waterfront may effect important nursery habitat.

conservationAction:
Skate and ray Total Allowable Catches (TAC) were established for parts of the European region in 2009, including International Council for the Exploration of the Sea (ICES) sub-areas VIII (Bay of Biscay) and IX (Iberian waters) where this species is known to occur. At present, the TAC for these Divisions is 3,800 tonnes per year for all skates and rays combined (regulations available online at http://faolex.fao.org). Much research is required on the species' population, size, trends, habitat, ecology, and threats while the harvest and population of the species needs monitoring. In order to protect the species, its habitat needs to be protected, its harvest managed, and education and awareness programs need to be implemented. 


taxonomicNotes:
Faria et al. (2013) state that both morphology and genetics support the current specific status of the Smalltooth Sawfish (Pristis pectinata) and propose modification of the distribution of the species to an Atlantic only range. No geographical structure of Smalltooth Sawfish subpopulations is present, and Western and Eastern Atlantic subpopulations of Smalltooth Sawfish likely represent separate units for conservation purposes.

redListCategoryRationale:
European regional assessment: Critically Endangered (CR) Smalltooth Sawfish (Pristis pectinata) is possibly extinct or its presence is uncertain in its former range in the Atlantic Ocean as a result of targeted fishing and bycatch in trawl and netting fisheries, compounded by habitat modification. Across the Atlantic Ocean, an absence of records from scientific surveys, anecdotal fisher observations, and fish landings data over its historic range infer a population reduction of ≥ 95% over a period of three generations (1984-2015, 30 years). The species can only be reliably encountered in the Bahamas, USA and parts of Central America, and in the Eastern Atlantic, in Sierra Leone, and possibly Guinea-Bissau and Mauritania. There is some uncertainty regarding the presence of sawfishes (Pristis spp.; referred to generically here due to a lack of species-specific information) in the Mediterranean Sea, with differing perspectives on whether sawfishes bred in the Mediterranean Sea, or whether they were regular visitors from elsewhere in the Eastern Atlantic. For the purposes of this assessment, the Mediterranean subpopulation is treated as a visitor from the Eastern Atlantic. The vast majority of accounts are historical, however a recent anecdotal record of a juvenile sawfish from a Tunisian fish market from ca. 1997 suggests that sawfish may still visit the Mediterranean Sea. Smalltooth Sawfish, as a visiting species, is assessed as Critically Endangered (Possibly Extinct) in the Mediterranean Sea under Criterion A2b+D based on the above-mentioned population reduction for the wider Atlantic Ocean and suspected small population size (< 50 mature individuals) in the Mediterranean Sea.

range:
The current range of Smalltooth Sawfish in the Eastern Atlantic and the Mediterranean Sea is uncertain due to species misidentification, lack of reporting, and the general contraction of its range.There is some uncertainty regarding the presence of sawfishes in the Mediterranean Sea (Tortonese 1956, Whitehead et al. 1984, Bilecenolu et al. 2002, Ferretti et al. 2015). Smalltooth Sawfish was included in historic faunal lists (Serena 2005) and the examination of historical records indicates that there were at least 78 bibliographic accounts of both species of sawfish over the past 500 years (Ferretti et al. 2015). These records include fresh captures of juvenile and adult specimens, which have led to the suggestion that a breeding population was present. It has been alternatively hypothesized that sawfish were a visitor species from areas of West Africa. Its depth range is 0.1-88 m.

population:
For the purposes of this assessment, Smalltooth Sawfish has been considered a visitor to the Mediterranean Sea from its core Eastern Atlantic range in tropical West Africa. Sawfishes have been described from the Mediterranean Sea since antiquity (< 2,000 years ago) and in medieval bestiaries, but these records lack taxonomic, geographic and quantitative detail (Ferretti 2014). There are few (n=82 bibliographic records, 21 museum specimens) records from the Mediterranean Sea over the past 500 years, and almost half of these records are duplications (Ferretti 2014, 2015). Many of these records are of rostra only and there is concern that they may have come from international trade rather than being caught locally (Ferretti 2014).There are historic records of freshly caught adults and juveniles, particularly from the Mediterranean coast of France. Possibly the most reliable records of Smalltooth Sawfish were taken from Provence, in the south of France. These were juveniles described by reputable ichthyologists in 1777 and 1810 (Ferretti 2014).There are two relatively recent 20th century records of Smalltooth Sawfish from the eastern Mediterranean Sea. However, these may represent records of Green Sawfish (Pristis zijsron) or Narrow Sawfish (Anoxypristis cuspidata). Unlike the Smalltooth Sawfish, these species occurred in the Red Sea, which has been connected to the Mediterranean Sea through the Suez Canal since 1867 (Ferretti 2014). Importantly, there is a recent record of a juvenile sawfish (Pristis spp.) from a Tunisian fish market from ca. 1997 (Ferretti et al. 2015), implying that they might still visit the Mediterranean region.Fish landings data over its historic range infer a population reduction of 95% over a period of three generations (1984-2015, 30 years) in the Eastern Atlantic, and this decline is inferred to have occurred through the whole of the European distribution. The species is considered a visitor in the Mediterranean Sea. 

habitat:
Information pertaining to the life history and habitat use of this species has not been published specific to Mediterranean waters, although it is inferred to be similar to, if not the same as, other regions from which it is documented extensively, such as Australia and Lake Nicaragua.A key uncertainty in understanding whether sawfishes are residents in the Mediterranean Sea is the strong seasonality in temperature, which in the northernmost sectors cools to below 12°C, which is below the thermal ranges of marine regions where this species has been historically detected.Moreno Iturria (2012) estimated its generation length to be 10.1 years.

threats:
The principal threats to Smalltooth Sawfish are from fishing; it was formerly targeted, but is now mostly taken incidentally in broad-spectrum fisheries (CITES 2007). The long toothed rostrum of sawfish makes them extremely sensitive to entanglement in any sort of net gear, gillnetting and trawling in particular. Depleted subpopulations mean that commercial targeting of most stocks is no longer cost-effective and bycatch mortality is now the primary threat to Smalltooth Sawfish (CITES 2007). However, there are indications that sawfish are at times targeted opportunistically for the shark fin trade (CITES 2007).Habitat degradation and loss also threaten sawfishes throughout their range (CITES 2007). The Smalltooth Sawfish relies on a variety of specific habitat types including estuaries and mangroves; these are all affected by human development (CITES 2007). Agricultural and urban development, commercial activities, dredge-and-fill operations, boating, erosion, and diversions of freshwater runoff as a result of continued coastal and catchment development has caused substantial loss or modification of these habitats (CITES 2007).

conservationAction:
All species of sawfish are listed on Appendix I of the Convention on International Trade of Endangered Species (CITES), which effectively bans commercial international trade in sawfish or their parts.Parties to the Barcelona Convention agreed in 2012 that sawfish as listed in Annex II of the Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean Sea -- which includes Recommendation GFCM/36/2012/1 -- cannot be retained on board, transshipped, landed, transferred, stored, sold or displayed or offered for sale, and must be released unharmed and alive, to the extent possible.

useAndTrade:
Sawfish rostra are culturally valued, economically valuable and hence are widely collected and frequently traded internationally (McDavitt and Charvet-Almeida 2004, McDavitt 2014).

redListContributors:
Dulvy, N.K., Ferretti, F., Carlson, J., Wiley, T. & Smith, K.


taxonomicNotes:
In a recent study, Faria et al. (2013) demonstrated that the existing taxonomy of the Pristidae required modification, recognising a total of five species in two genera. Pristis pristis had been recognised previously as consisting of up to three species (Pristis pristis, P. microdon and P. perotteti), but utilising a combination of mitochondrial DNA and morphological characters appears to be one species. While the P. pristis group is best considered a single species, it can be composed of a network of geographical units (subpopulations) that are not genetically distinct, but may be considered ecologically different.   Pristis pristis, has been referred to by many other names throughout its range. It was formerly known as P. perotteti in the Atlantic and sometimes in the Eastern Pacific, and P. microdon in the Indo-West Pacific.

redListCategoryRationale:
European regional assessment: Critically Endangered (CR)Largetooth Sawfish (Pristis pristis) is possibly extinct or its presence is uncertain throughout most of its former range in the Atlantic Ocean as a result of targeted fishing and bycatch in trawl and netting fisheries, compounded by habitat modification. It is a large (at least 6.5 m total length) euryhaline species, with juveniles occurring in freshwater systems and adults in marine and estuarine environments. It formerly had a widespread tropical range, consisting of four subpopulations (Eastern Atlantic, Western Atlantic, Eastern Pacific and Indo-West Pacific); all subpopulations have undergone significant population declines and the species is now apparently extinct in many former range states. Across the Atlantic Ocean, an absence of records from scientific surveys, anecdotal fisher observations, and fish landings data over its historic range infer a population reduction of ≥95% over a period of three generations (i.e., 1964 to present). In the Eastern Atlantic, there have been very few (< 10) records in the past decade. There is some uncertainty regarding the presence of sawfishes (Pristis spp.; referred to generically here due to a lack of species-specific information) in the Mediterranean Sea, with differing perspectives on whether sawfishes bred in the Mediterranean Sea, or whether they were regular visitors from elsewhere in the Eastern Atlantic. For the purposes of this assessment, the species is treated as a visitor in the Mediterranean Sea. The vast majority of accounts are historical, however a recent anecdotal record of a juvenile sawfish from a Tunisian fish market from ca. 1997 suggests that sawfish may still visit the Mediterranean Sea. Largetooth Sawfish, as a visiting species, can be considered Critically Endangered in the Mediterranean Sea based on the above-mentioned population reduction for the wider Atlantic Ocean and suspected small population size (< 50 mature individuals) in the Mediterranean Sea under Criteria A2b+D.

range:
Largetooth Sawfish (Pristis pristis) comprises four distinct subpopulations: Eastern Atlantic, Western Atlantic, Eastern Pacific and Indo-West Pacific. In West Africa, there have been only two countries with confirmed records for the region in the last 10 years (Guinea-Bissau in 2003, 2004 and 2005, and Sierra Leone in 2003) and unconfirmed records (Pristis spp.) from one other country (Mauritania in 2010) (Tamburello et al. 2014). There is some uncertainty regarding the presence of sawfishes in the Mediterranean Sea (Tortonese 1956, Whitehead et al. 1984, Bilecenoğlu et al. 2002). Largetooth Sawfish was included in historic faunal lists (Serena 2005), and the examination of historical records indicates that there were at least 78 bibliographic accounts of both species of sawfish over the past 500 years (Ferretti et al. 2015). These records include fresh captures of juvenile and adult specimens, which has led to the suggestion that a breeding population was present. It has been alternatively hypothesized that sawfish were visitor species from areas of West Africa (this seems more likely for Largetooth Sawfish given the generally tropical nature of this species).

population:
For the purposes of this assessment, Largetooth Sawfish has been considered a visitor to the Mediterranean Sea from its core Eastern Atlantic range in tropical West Africa. Sawfishes have been described from the Mediterranean Sea since antiquity (< 2,000 years ago) and in medieval bestiaries, but these records lack taxonomic, geographic and quantitative detail (Ferretti 2014). There are few (n=82 bibliographic records, 21 museum specimens) records from the Mediterranean Sea over the past 500 years, and almost half of these records are duplications (Ferretti 2014, 2015). Many of these records are of rostra only and there is concern that they may have come from international trade rather than being caught locally (Ferretti 2014). The first record of Largetooth Sawfish in the Mediterranean Sea was in 1573 while the last one was caught in 1959 (Ferretti 2014). Records come mainly from western Mediterranean coasts (France, Italy and Spain). Catch records of sawfishes were reported from eastern Languedoc, Provence, the Gulf of Naples, and the Adriatic Sea. Importantly, there is a recent record of a juvenile sawfish (Pristis spp.) from a Tunisian fish market from ca. 1997 (Ferretti et al. 2015), which supports the notion that this species may still visit the Mediterranean region.Fish landings data over its historic range infer a population reduction of ≥ 95% over a period of three generations (i.e., 1964 to present) in the Eastern Atlantic, and this decline is inferred to have occurred through the whole of the European distribution, even when the species is treated as a visitor in the Mediterranean Sea. 

habitat:
Information pertaining the life history and habitat use of this species has not been published specific to Mediterranean waters, although it is inferred to be similar to, if not the same as, other regions from which it is documented extensively, such as Australia and Lake Nicaragua.A key uncertainty in understanding whether sawfishes are residents in the Mediterranean Sea is the strong seasonality in temperature, which in the northernmost sectors cools to below 12°C, which is below the thermal ranges of marine regions where this species has been historically detected. The generation length of this species is estimated to be 17 years.

threats:
The principal threats to this species are from fishing; it was formerly targeted, but is now mostly taken incidentally in broad-spectrum fisheries (CITES 2007). The long toothed rostrums of sawfishes make them extraordinarily sensitive to entanglement in any sort of net gear, gillnetting and trawling in particular. The exploitation of elasmobranchs is high in many parts of the Largetooth Sawfish’s range, particularly in coastal areas and freshwater systems. Unregulated and unmanaged fisheries, and habitat loss and degradation all threaten sawfishes across large parts of its range.For at least part of its life cycle, Largetooth Sawfish relies on a variety of specific habitat types including freshwater systems, estuaries and mangroves; these are all affected by human development (CITES 2007). Agricultural and urban development, commercial activities, dredge-and-fill operations, boating, erosion, and diversions of freshwater runoff as a result of continued coastal and catchment development has caused substantial loss or modification of these habitats (CITES 2007). Mining activities pose a risk to Largetooth Sawfish through freshwater habitat alteration or potential pollution events. Alterations to river courses are a threat to Largetooth Sawfish, which migrate upstream in early life stages. 

redListContributors:
Dulvy, N.K., Ferretti, F., Carlson, J. & Smith, K.


taxonomicNotes:
This species can be confused with other Amblyraja species with different distributions, such as Amblyraja georgiana (M. Stehmann pers. comm). In the northwest Atlantic, it is easily confused with Jensen' s skate (A. jenseni). Refer to Bigelow and Shroeder (1953), Jensen (1948) and Stehman and Burkel (1984).

redListCategoryRationale:
European regional assessment: Least Concern (LC) Arctic Skate (Amblyraja hyperborea) is widely distributed in the continental slope waters of the Northeast Atlantic. Primarily found at depths greater than most fisheries operating in this region, it likely has limited interaction with human threats and is not of interest to fisheries. The life history parameters are poorly known, but it likely exhibits low productivity similar to other deepwater skates. This species is commonly encountered during research surveys as well as demersal trawl and longline fisheries on the slope of the eastern Norwegian Sea and more recently in bottom trawl surveys off the Spitsbergen/Svalbard and Franz Josef Land archipelagos. Given that this species is primarily distributed outside the range of current fishing activity in European waters, and has a wide geographic range beyond fished areas, it is assessed as Least Concern. Continued monitoring of catches and potential expanding deepwater fisheries, and the collection of life history data should be a priority.

range:
Arctic Skate (Amblyraja hyperborea) is found in the Northeast Atlantic from the Kara Sea, the southeast Barents Sea (Franz Josef Land and northern Novaya Zemliya Archipelagos), and the Spitsbergen/Svalbard archipelago to the Greenland-Iceland-Faroe-Shetland Ridge and northern Norway (Paz 2003, Dolgov 2013). Any records of Arctic skate from the North Sea and eastern English Channel as reported by England, Wales and Northern Ireland are likely the result of misidentification or incorrect use of species codes (ICES 2013).

population:
No data on population size are available, however survey data indicate that it is the dominant skate species in certain areas, such as Davis Strait and southern Baffin Bay (Jørgensen 2005, 2011). It was caught commonly during research cruises conducted on the slope of the eastern Norwegian Sea from 1984 to 1987 and in 1995 (Skjæraasen and Bergstad 2001). In the Spanish bottom trawl survey carried out on the Spitsbergen/Svalbard archipelago in 2003, it was also one of the main species caught (Paz 2003). Average annual catch rate between 1992 and 2005 was 0.6 individuals per km2 in the Barents Sea, which is considered ‘rare’ (Williams et al. 2008). Between 1996 and 2001 in the Barents Sea, the largest bycatch was 60 to 100 kilograms (kg) per hour haul, and more than 50 individuals per 1,000 hooks (Dolgov et al. 2005a). Average bycatch in the trawl fishery was six to 10 kilograms per hour haul and the maximum catch rate was 156 kg per hour. In the longline fishery, average bycatch rates were 10 to 25 individuals (or 35 to 75 kg) per 1,000 hooks, and catch rates reached 368 kg per 1,000 hooks (equivalent to a catch per vessel per day of approximately nine tonnes). These catch rates suggest that on average, this skate accounted for approximately 20% of longline catches, although they could comprise 99% of some catches. These catch rates suggest that it is a relatively common species in parts of the Northeast Atlantic.

habitat:
The species is widespread on deep shelf waters and along continental slopes. Records range predominantly between 300 and 1,500 m, but it can reach depths of 2,500 m (Ebert and Stehmann 2013). This is an egg laying species, and size on hatching is 16 to 18 cm total length (TL; Bigelow and Schroeder 1953). Maximum size reported is 106 cm TL (Last and Stevens 1994); although the maximum recorded size in the Barents Sea is 74 cm TL (Dolgov 2011). In Norwegian waters the highest frequency of catches observed was at depths between 1,050 to 1,250 m. In the deepest areas sampled (2,000 to 2,050 m) no catches were made, suggesting a lower limit to its depth range (Skjæraasen and Bergstad 2001). This species appears to live almost exclusively at temperatures below 4ºC (Bigelow and Schroeder 1953). In the Barents Sea, it prefers bottom temperatures about 0°C (Dolgov et al. 2005a).

threats:
This skate is taken as bycatch in deepwater trawl and longline fisheries. In Davis Strait, it is taken as bycatch in the Greenland Halibut (Reinhardtius hippoglossoides) fishery. In the Barents Sea it is taken in trawl fisheries targeting Cod (Gadus morhua) and Haddock (Melanogrammus aeglefinus) at depths of 300 m, and longline fisheries targeting mainly Greenland Halibut, Blue Catfish (Anarhichas denticulatus) and Cod at depths around 300 m (Dolgov et al. 2005b). These longline fisheries operate at depths from 130 to 847 m. Average bycatch rates in the longline fishery were 10 to 25 fish (or 35 to 75 kg) per 1,000 hooks, and this species was estimated to constitute approximately 20% of total longline catches (Dolgov et al. 2005b). However, it should be noted that the uncertainty of the estimates from this method is high (approximately ±45%). Preliminary estimates indicate that total annual skate bycatch in these fisheries is 723 to 1,891 tonnes, and Thorny Skate (Amblyraja radiata) composes the great majority of catches (90 to 95% of the total skate catch). Skate catches are mainly discarded in the Barents Sea, although in 2000, about 200 tonnes of grouped Thorny and Arctic Skate were landed (Dolgov et al. 2005b), so future trends should be monitored.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).Deepwater fisheries in the Northeast Atlantic have decreased in effort gradually over the past decade (Dransfeld et al. 2013, STECF 2014), but should still be monitored in case of future expansion, which could pose a threat to this skate.Research to collect information on the biology, ecology, use, and fishery data of this species should be a priority.

redListAssessors:
Stehmann, M.F.W., Dolgov, A., Farrell, E., Walls, R., Barker, A.S., Pasolini, P. & Orlov, A.


taxonomicNotes:
In the northwest Atlantic, this species is easily confused with Arctic skate (A. hyperborea) with overlapping distribution (Jensen 1948, Bigelow and Shroeder 1953, Stehman and Burkel 1984).

redListCategoryRationale:
European regional assessment: Least Concern (LC) Jensen’s Skate (Amblyraja jenseni) is a little known deepwater skate, occurring in waters off Ireland in the Northeast Atlantic, including the Mid-Atlantic ridge. The species occurs at depths of 167−2,548 m. The full extent of this species’ range at greater depths is poorly understood. The occurrence of this species over the Mid-Atlantic Ridge, and its presence at unfished depths in the Northeast Atlantic, offer it refuge from fishing pressure. Increasing density with depth suggests that the majority of the population likely occurs well beyond areas surveyed and fished. In the absence of major potential threats and data to suggest declines in abundance, it is assessed as Least Concern in the Northeast Atlantic region. If deepwater fisheries expand to greater depths within this species’ range in future, this assessment should be revisited.

range:
This skate is known to occur in most temperate North Atlantic slope waters and the Mid-Atlantic Ridge (Templeman 1965, Orlov et al. 2006). In the Northeast Atlantic it has been recorded in waters north of Ireland (Gordon and Duncan 1987, 1989; Quero et al. 2000), within the Rockall Trough west of Scotland, and in Porcupine Seabight west of Ireland (Ebert and Stehmann 2013). It has also been recorded in deep waters along west Greenland, in Denmark Strait, and around Iceland (Jónsson and Pálsson 2006). In the Northeast Atlantic, the species is present at depths between 1,800 and 2,190 m.

population:
No information is currently available on population size or structure. A scientific survey expedition during the summer of 2004, using bottom trawls (to depths of 3,500 m) and bottom longlines (to depths of 4,500 m) off the Mid-Atlantic Ridge, from the Azores to the Charlie-Gibbs Fracture Zone, collected only 14 individuals (Orlov et al. 2006). Although nothing is known of the population structure of this species, differences found in the external morphology in different parts of this skate’s range may indicate that separate populations exist. Given its limited interaction with deepwater fisheries and this species’ deep range, it is suspected that the population is stable in European waters.

habitat:
This skate is a bathydemersal species, known to occur at depths of 167−2,548 m and likely deeper (at an average depth of 1,213 m) (Orlov et al. 2006). In the Northeast Atlantic this species is known to occur between 1,800 and 2,190 m, yet the maximum depth at which this species occurs is unknown. On the Mid-Atlantic Ridge this species’ average size on record is 92.61 cm total length (TL), while the average size on the European continental slope is 46.85 cm TL (Orlov et al. 2006). Mean size for a limited sample of female skates is 72.31 cm TL and for males, 80.3 cm TL (Orlov et al. 2006). Maximum recorded size is 112 cm TL (Orlov et al. 2006). This skate is oviparous, with egg capsules 12.3 by 7.6 cm long, similar to but larger than those of Arctic Skate (Amblyraja hyperborea; Ebert and Stehmann 2013).

threats:
This species is taken occasionally as bycatch by deepwater bottom trawls and longlines. It is usually discarded, although larger specimens may occasionally be landed (Ebert and Stehmann 2013). Its occurrence over the Mid-Atlantic Ridge and at great depths in the Northeast Atlantic offer refuge from fishing pressure.

conservationAction:
Although this species is taken infrequently as bycatch, there are management measures in place in the Northeast Atlantic for skates and rays, and such policies may affect it as well. In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).Research is needed on the population size and trend of the species.

redListAssessors:
Farrell, E., Orlov, A., Walls, R., Stehmann, M.F.W. & Barker, A.S.


taxonomicNotes:
McEachran and Dunne (1998) moved this species from genus Raja to Amblyraja.

redListCategoryRationale:
European regional assessment: Least Concern (LC)Thorny Skate (Amblyraja radiata) is found in the Northeast Atlantic at depths of 18–1,400 m, but is most common from 27–439 m. This species is common in the northern region of the Northeast Atlantic. It is the most abundant skate in the central and northern North Sea, and showed a marked increase in abundance between 1970 and 1983 in the central North Sea and from 1982–1991 in English groundfish surveys. More recent surveys, from 1991–2011, indicated a decline in the North Sea, but this is believed to be due to a change in survey gear, rather than an actual change in abundance. This species is only occasionally landed as bycatch in southern and southeast North Sea demersal fisheries, and its distribution lies outside the main beam trawling areas in this region. It is also the most abundant skate species in the Barents Sea, where it is a common bycatch species of demersal fisheries. It reaches first maturity at a relatively small size (44 cm total length) and demographic modelling suggests it is less susceptible to fishing mortality in this region than larger skate species. For these reasons Thorny Skate is assessed as Least Concern in European waters.

range:
In the Northeast Atlantic, this skate’s northern range extends to Svalbard, the Barents Sea, and off Greenland and Iceland (ICES 2013), and southwards to the Kattegat (Denmark), Ireland and the southern North Sea. It is found in abundance throughout the Norwegian Sea between latitudes of 62 and 72oN (Williams et al. 2008).Some reports of this species are likely to be inaccurate, owing to confusion with Thornback Skate (Raja clavata). In particular, nominal reports of this species from the Faeroe Islands, English Channel (Martin et al. 2010) and Celtic Seas (Silva et al. 2012) are believed to be inaccurate.Its depth range is 18-1,400 m.

population:
Generally, this species is thought to be stable in European waters, although changes in trend are apparent. In the North Sea, which is the southern limit of this species’ range, long-term survey trends have shown an overall increase in abundance followed by a more recent decrease. The International Bottom Trawl Survey (IBTS, 1979–present) and survey data collected in Dutch coastal waters between 1951 and 1994 reported that this is the most abundant skate species over the wider North Sea, and has shown a marked increase in the central North Sea between 1970 and 1993 (Bergstad 1990, Heessen and Daan 1996, Walker and Heessen 1996). In research cruises carried out in the northeast North Sea and Skagerrak from 1984–1987 and 1995–1996 the species was caught in 269 of a total of 639 trawls (41%). More recent IBTS survey data from 1991–2011, showed a gradual decrease in the first quarter from almost eight individuals per hour effort in 2000, to approximately one individual per hour in 2011, representing a > 85% decrease, whereas the third quarter IBTS showed stable catch rates following a distinct peak of approximately 6.5 individuals per hour in 2001 (ICES 2012). This decline is believed to be a result of a change in survey gear (Ellis et al. 2005), rather than reflecting an actual change in abundance. Total biomass of this species in the North Sea has been estimated in the order of 100,000 tonnes (t) (Sparholt and Vinther 1991) but sampling effort was restricted by depth and area, omitting the deeper northeast part of the North Sea and the Skagerrak. While the overall North Sea stock is thought to be stable, there are concerns about confusing this species with Thornback Skate (ICES 2013). In the Norwegian Sea, annual mean abundance of Thorny Skate has been stable (mean catch rates of about 55 individuals per km2) between 1994 and 2005 (Williams et al. 2008), but decreased in the Barents Sea from 1999–2012. The Barents Sea population was originally considered stable at current fishing levels (Drevetnyak et al. 2005), comprising > 90% of skate biomass caught across the Barents Sea (Dolgov et al. 2005, Byrkjedal and Høines 2007). However, from 1999-2012 mean catches of this species decreased in a Russian demersal trawl survey from 5.0–6.2 individuals per hour in 2001–2002 to 3.2–3.3 individuals per hour in 2011–2012, which represents a 42% decline in abundance over this decade. In the Norwegian Sea, trawl catch rates for this species were higher than trawl catch rates in the Barents Sea (61 kg per 100 trawl hours for the Norwegian Sea and 43 kg per 100 trawl hours for the Barents Sea), but lower for longline catches (119 kg per 10,000 hooks and 135 kg per 10,000 hooks, respectively; ICES 2012). Scottish trawl surveys in the central and northern North Sea for the period 1929–1956 and 1981–1995 show that this species was caught throughout the two periods and increased in abundance between 1981 and 1995 with an unchanged length-frequency pattern over both periods (Greenstreet and Hall 1996, Walker and Hislop 1998). English groundfish surveys from 1982–1991 also showed a marked increase in catches (Ellis et al. 2005). In Iceland, this species has historically been discarded from a variety of fishing gears. A recent increase in landings, from nine tonnes in 1982 to 1,352 tonnes in 2011, suggests increased retention driven by local consumption (ICES 2012). It is estimated that the population is stable in European waters.

habitat:
The depth range of Thorny Skate is approximately 18–1,400 m but it is most common at 27–439 m (McEachran and Musick 1975, McEachran 2002, Kulka and Miri 2003). It is found over a wide variety of bottom types from sand, gravel, broken shell and pebbles, to soft mud (McEachran 2002). Off the west coast of Norway, shallow areas are probably used as nurseries (Skjæraasen and Bergstad 2000) and the Barents Sea is a spawning ground (ICES 2006).This egg laying skate may reproduce throughout the year (del Río and Junquera 2001, del Río 2002, Sulikowski et al. 2005a, b) and produces between 10–45 eggs (Templeman 1987, Walker 1998). Size at birth is 8–12 cm total length (TL; Berestovskii 1994, Walker 1998, Kulka and Miri 2003). In the North Sea, Skjæraasen and Bergstad (2000) reported a size at maturity of 44 cm total length (TL) for both males and females. Also in the North Sea, McCully et al. (2012) reported length at 50% maturity as 36.2 cm TL for males and 38.2 cm TL for females. The largest specimen of Thorny Skate reported by McCully et al. (2012) was 49 cm TL. Again, this is markedly smaller than the maximum size reported from the Norwegian Sea of 90 cm TL, and from the central North Sea of at least 60 cm TL (Walker 1998).

threats:
This species is occasionally landed as bycatch in Northeast Atlantic demersal fisheries, but is likely less sensitive to exploitation in this region than other skates because of its small length at maturity. It is also distributed outside the major beam trawling areas in the southern and southeast North Sea (Walker and Heessen 1996). In the Barents Sea this skate was found to be the dominant skate species, comprising 90–95% of the total weight of skates caught in both survey and trawl fisheries bycatch data (Dolgov et al. 2005, ICES 2013). Relative catch per unit effort (CPUE) in this region indicates that biomass and abundance increased from 1997–2003  (Dolgov et al. 2005, ICES 2006), and remained almost unchanged from 1998–2001, suggesting stable stocks in this region (Dolgov et al. 2005, Drevetnyak et al. 2005, ICES 2006). In the Norwegian Sea, this species dominated catches (and presumably discards) from depth range of 60–400 m in 2008–2009 (Vollen 2010). These catches consisted of large individuals (36-55 cm TL) of both sexes, and were caught by Russian commercial bottom trawl and demersal longline fisheries (Vinnichenko et al. 2010). This species may be confused with Thornback Skate in some reports.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org)Since 2008, the European Commission has obliged member states to provide species-specific landings data for the major North Sea species, including this species, in order to improve understanding of skate stocks in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009), and has been ongoing since 2008 (CEC 2013).Monitoring of the harvest trends is encouraged.

useAndTrade:
In the northwest Atlantic, the wings of this species are exported to Europe for human consumption. In the northeast Atlantic, Thorny Skates are taken as incidental bycatch in trawl fisheries, but there (North Sea, Irish Sea, Barents Sea), the species is not considered as desirable and thus it is not targeted.

redListAssessors:
Kulka, D.W., Sulikowski, J., Gedamke, J., Pasolini, P. & Endicott, M.

redListContributors:
Ellis, J., Fordham, S., Walls, R. & Dolgov, A.


taxonomicNotes:
Currently, this listing for Dipturus batis represents a species complex. A recent taxonomic review indicates that D. batis will soon be split into two separate species (Iglésias et al. 2010).

redListCategoryRationale:
European regional assessment: Critically Endangered (CR) This European regional assessment is based on the current global assessment for Dipturus batis, as a species complex. A recent taxonomic review indicates that soon this is likely to be split into two separate species (Iglésias et al. 2010), at which point a reassessment will be required. This skate, the largest European rajid, was once an abundant constituent of the demersal fish community of north-western Europe. It formerly occupied the shelf and slope areas of the Mediterranean excluding North Africa west of Morocco but now appears to be virtually absent from much of this range. Caught as bycatch of multispecies trawl fisheries, which cover much of its shelf and slope habitat. Fisheries data indicate that populations of D. batis have undergone an extremely high level of depletion in the central part of its range around the British Isles since the early 20th century (the three generation period). It has been extirpated from most inshore areas, but is still caught in Scottish waters, especially around the Shetlands and off North-west Scotland, and also along the shelf edge and in the Celtic Sea. Fishing capacity and effort in the Mediterranean have also increased substantially over the later half of the 20th century. Accurate international species-specific landings data are lacking, although Icelandic landings have declined. French landings appear stable, though this is likely to be attributed to a re-direction of fishing effort from shelf seas (where common skate are now very rare) into deeper water. The life history and demography of this species allow little capacity to withstand exploitation by fisheries, its large body size renders it catchable by fishing gears even from birth. As fishing pressure on this species is unlikely to be reduced in the future, it is assessed as Critically Endangered throughout its range.

range:
The historical geographical range of Dipturus batis covered much of the continental shelf of the northeast Atlantic Ocean, from Madeira and the coast of northern Morocco in the south, to Iceland and northern Norway in the north, including the Mediterranean Sea. In several parts of its range, including the Western Baltic, western Mediterranean and southern North Sea, it is considered scarce (Stehmann and Bürkel 1984). It is absent from the Black Sea and Levantine Mediterranean basin (Serena 2005). At the start of the twentieth century it was considered to have a wide distribution over the shallower waters of the continental shelf surrounding the British Isles, albeit more common in the northern and western regions (Walker and Heesen 1996). Though individual specimens are reported very occasionally from the Irish Sea, Bristol Channel and central North Sea, the current range tends to occupy the deeper waters off northwestern Scotland and in Celtic Sea, and along the edge of the continental shelf. Its depth range is zero to 600 m.

population:
Northeast Atlantic Ocean: Common Skate, as the name implies, was historically one of the most abundant skates and rays in the northeast Atlantic Ocean. It was widely distributed in the seas surrounding the British Isles, though catch rates of this species in this area declined during the 20th century. By the 1970s common skate was considered extirpated from the Irish Sea (Brander 1981), and they have also disappeared from the English Channel and the southern and central North Sea (Walker 1999, Rogers and Ellis 2000). Though individual specimens are reported occasionally from these areas (e.g., Ellis et al. 2002, Ellis et al. 2005), common skate are now only regularly observed off northern and north-western Scotland, Celtic Sea and along the edge of the continental shelf (>150 m depth).  Mediterranean: A time series of comparative trawl surveys in the Gulf of Lions between 1957-1960 indicate that D. batis was historically present in both shelf and slope trawl surveys. It was captured in 10% of hauls (n=27) in shelf surveys (coast-150 m depth) and in approximately 17% of hauls (n=37) in slope surveys (150-800 m) (Aldebert 1997). In contrast, comparable surveys carried out from 1966-1995 in the Gulf of Lions (totaling 1,295 hauls) did not record this species (Aldebert 1997). In the Adriatic Sea, the "Hvar" 1948 trawl surveys (based on 138 valid hauls taken in the spring-summer of 1948) revealed D. batis present in 3.2% of hauls. In a comparable survey conducted in the spring-summer of 1998 (127 valid hauls) (MEDITS) it was not recaptured, suggesting D. batis may now be absent from this area (Jukic-Peladic et al. 2001). The MEDITS survey began in 1994 while another study of the Adriatic Sea had begun in 1985 (GRUND), with each project carrying out one survey per year. A single individual was captured in the first GRUND survey of 1985 and since then no specimens have appeared in the Adriatic in either of these surveys (Marano et al. in press). It is now regarded as locally extinct in the Adriatic Sea (Tinti et al. 2003). Although these surveys are exhaustive, it should be noted that the MEDITS net is thought to have a low sampling efficiency of truly benthic species (Jukic-Peladic 2001). Along the Algerian coast from 1996-1997, regular systematic surveys of elasmobranchs present in markets have been undertaken. Although eight species of skate have been recorded, D. batis has not been reported (Hemida 1998). Tunisian fisheries use prawn trawl and larger "French" trawls, which frequently capture skates and demersal sharks. While this species has been documented from Tunisian waters in the early part of the 20th century, it has not been recorded since 1971 and it is now presumed absent from this area (Bradaï 2000).  The former range of this skate included much of the west, north and eastern shelf and slope habitat of the Mediterranean. These results suggest that this species may only be found in the western area of the Mediterranean (Morocco, Spain and France) representing a substantial reduction in area of occurrence of this species.

habitat:
This demersal species is found from shallow coastal waters down to depths of 600 m, although it is primarily within the 200 m depth range (Stehmann and Burkel 1984, Bouchot 1987, Serena 2005). This is the largest species of skate attaining a length of more than 250 cm. The age and growth of D. batis has been reported by Du Buit (1972 1976) and more recently by Fahy (1991) who examined the vertebrae of 75 individuals landed in Ireland. Du Buit (1976) gave the following growth parameters: Maximum length 253.73 cm; k = 0.057; t0 = -1.629. Males are thought to mature at a length of 125 cm (Du Buit 1972) and although the size at maturity has not been accurately determined for females, an estimate of 150 cm was presented in the 2000 Red List assessment (Ellis et al. 2000). Du Buit (1976) determined that maturity is reached at 11 years of age and that individuals may live for 50 years. The overall sex ratio has been reported to be approximately 1:1, although this may differ geographically and seasonally (Fulton 1903, Steven 1933). The fecundity has not been accurately determined but was estimated at 40 eggs/year over the spawning season (Brander 1981) and the rate of reproduction has been calculated at 0.38. Oviparous, with large egg-cases covered with close-felted fibres (150 to 250 mm long and 80 to 150 mm wide reported in the Mediterranean (Serena 2005) and 145 to 245 mm long in the UK (Clark 1922, Wheeler 1969). The egg-cases are deposited in spring and summer in both the Mediterranean and Northeast Atlantic (Clark 1922, Wheeler 1969, Serena 2005). The young hatch at a lengths of up to 21.2 to 22.3 cm (Clark 1926). There is no detailed information on the developmental time.  Dipturus batis preys mostly on crustaceans and teleost fish, although Steven (1947) reported several species of elasmobranch, including other species of rajid, in the stomach contents of fish landed in Devon and Cornwall. The skate hunts actively and envelops its prey prior to capture and ingestion. The dark ventral surface may facilitate hunting in the pelagic phase.  While there is almost no life history and ecological information specific to the Mediterranean it is likely that it is similar to that exhibited in more northerly waters.

threats:
Northeast Atlantic: Rajids are an important component of the demersal fisheries of northwest Europe (Holden 1977) and Dipturus batis has traditionally been landed due to its large size (see Ellis et al. 2000 for details). It has taken in targeted fisheries where/when abundant, and as a bycatch elsewhere within its range. Accurate species-specific landings data are not available, though species-specific data from Iceland indicate declining landings of this species. Though French data appear more stable, these landings include landings from fisheries operating towards the edge of the continental shelf, where the population now appears to be concentrated. Given that this species is likely to be taken in trawl and gillnet fisheries that target high-value telesosts (e.g., megrim, anglerfish and hake), it is unlikely that fishing effort will decrease. Common skate are targeted by recreational fisheries (e.g., off Scotland), most anglers release captured individuals.  Mediterranean The situation appears similar in the Mediterranean, where D. batis is probably captured as part of the bycatch of multispecies trawl fisheries. Benthic trawl effort has increased both numerically and in technological terms in the shelf and slope area of the Mediterranean over the last 50 years. For example, the Gulf of Lions area was initially exploited by small-scale benthic trawl fisheries comprising 27 small low powered boats (total nominal horse power of 2,700 hp), more recently effort has increased to a total nominal horse power of 19,940 hp (1974 to 1987). Since then half of the fishing effort has been displaced to targeting small pelagic fish (Aldebert 1997). The Adriatic Sea is subject to trawling mainly by Italian, Croatian, Slovenian and Albanian fleets, however, no landings data are available (Jukic-Peladic et al. 2001). The large body size, slow growth, low fecundity and large size of juveniles of this species makes it especially vulnerable to fishing exploitation when compared to other rajids (Brander 1981, Walker and Hislop 1998, Dulvy et al. 2000, Dulvy and Reynolds 2002). Moreover, although only large individuals may be landed for consumption, most size classes are taken in fishing nets, including the eggs (which are often found in the trawl cod-end; Ragonese et al. 2003), as the legal mesh size used in much of the Mediterranean is approximately 20 mm. Considering the large size at maturity (around 130 cm) this means that the exploitation of juveniles is likely to be high. Additionally D. batis has been found to have undergone declines and disappearance from other shelf seas, notably the Irish and North Sea (Brander 1981, Walker and Hislop 1998, Dulvy et al. 2000).

conservationAction:
It is recommended that suitable non-trawling areas are defined to protect both adults and deposited eggs as these are both susceptible to capture by trawling gear.  Northeast Atlantic:  Though there are no species-specific management measures for this species, there is a TAC for skates and rays in the North Sea and adjacent waters, and they may benefit from more generic management measures for demersal fisheries (e.g. mesh size regulations, effort reduction). Diptutus batis has been identified by the International Council for the Exploration of the Sea (ICES) Study Group on Elasmobranch Fish as one which "requires information on either fisheries statistics, biology or status of exploitation" or in the case of D. batis, all three (Anonymous 1995). Demographic information indicates that population recovery might be achieved by allowing increasing juvenile survival (Walker and Hislop 1998). Dipturus batis was proposed for strict protection under the UK Wildlife and Countryside Act in 2001; a decision is still (2006) awaited from government. Dipturus batis is also a Biodiversity Action Plan (BAP) species in the UK, and was listed on the OSPAR Priority List of Threatened and Endangered Species.  Mediterranean: For the conservation of chondrichthyans within the Mediterranean region, the FAO SAC Subcommittee on the Environment and Ecosystem recommended that all fishing states implement a Mediterranean Action Plan for the Management and Conservation of chondrichthyans, in line with IPOA sharks (International Plan of Action on the management and conservation of chondrichthyans).  The MEDLEM project was adopted at the last SAC meeting (FAO, Rome 2005) for data collection within the Mediterranean basin on large elasmobranches. The Bern Convention encourages research programs aimed at the assessment of the conservation status of chondrichthyans in the Mediterranean Sea (Serena et al. 2002). In Italy a national action plan (PAN-SHARKS) was co-ordinated by ICCRAM (Central Institute for Marine Research) within the guidelines of the Bern Convention and FAO IPOA-Sharks (Serena et al. 2002, Vacchi and Notarbartolo 2000). The Barcelona Convention proposed this species for urgent legal protection under its Mediterranean Action Plan. A new European requirement is that common skates, when caught, should be returned to the sea. This applies only to the North Sea.

useAndTrade:
This species is taken in targeted fisheries where/when abundant, and as a bycatch elsewhere within its range.

redListReviewers:
Cavanagh, R.D., Valenti, S.V. & Heenan, A.

redListAssessors:
Dulvy, N., Notarbartolo di Sciara, G., Serena, F., Tinti, F., Ungaro, N., Mancusi, C. & Ellis, J.


taxonomicNotes:
Dipturus nidarosiensis may be a composite species with a small and large morphotype similar to that seen in Dipturus batis-complex (Iglesias et al. 2010) and Dipturus oxyrinchus-complex. Further genetic research is needed before a taxonomic revision is made, but Dipturus nidarosiensis refers to the larger morphotype and for now the smaller morphotype is referred to as Dipturus sp., as described in the Food and Agricultural Organisation of the United Nations (FAO) catalogue by Ebert and Stehmann (2013). 

redListCategoryRationale:
Norwegian Skate (Dipturus nidarosiensis) is a deepwater species that occurs in the Northeast Atlantic. It is taken as bycatch in commercial fisheries, but little information is available on landings. This is one of the largest European skates (up to 230 cm total length), and as such, it has low productivity and high catchability, similar to other large skates that have been heavily affected by even moderate levels of bycatch. Skates with a similar range are known to sustain some level of bycatch. Given the status of other Dipturus species in European waters, the low catch levels in surveys and fisheries, and the slow life history of the species, it is suspected to have declined by nearly 30% over the past 30 years (three-generation period). Therefore, the Norwegian Skate is assessed as Near Threatened in the European region as it is close to meet the threshold for threatened under Criterion A2. Further research is required to understand the taxonomy and population status of this species. Fisheries catches and landings should also be monitored.

range:
This species occurs in the Northeast Atlantic in the fjords of central and southern Norway, along the slopes off southern Iceland, western Scotland (including Rockall Trough) and west of Ireland as well as along the Mid-Atlantic Ridge and Iceland-Faroe Ridge. It is present, but uncommon, in the Bay of Biscay (Stehmann and Bürkel 1984, ICES 2007). It has also been reported in the coastal region of the Norwegian Sea (ICES 2012) as far north as 68oN at depths of 140–590 m (Williams et al. 2008), but its known range is primarily south of 65oN (Pethon 2005). Nominal records come from the shelf edge of Celtic Sea, although these may be misidentified specimens of another Dipturus species.Fourteen specimens were caught off Sardinia in the western central Mediterranean Sea between 2005 and 2008 at depths of 6001,420 m (Cannas et al. 2010), but these records likely refer to the smaller morphotype, Dipturus sp. (Ebert and Stehmann 2013).Its depth range is 200-1,000 m.

population:
This species is moderately rare where it occurs. There are historical records from Rockall and the Norwegian Deep, but its current status is uncertain (ICES 2007). In the Annual Autumn Bottom Trawl Surveys of the north Norwegian Coast, mean catch was 0.5 individuals per square kilometre between 1992 and 2005 (Williams et al. 2008). The status of the population west and southwest of England and Ireland is also uncertain (ICES 2012). There are however suspected declines in areas of the shelf margin that are heavily fished. Despite a lack of species-specific population information, it is possible to infer from the statuses of similar large-bodied skate species and suspicion of trends that the population is likely decreasing, especially because it is larger than its congeners and likely to have a low intrinsic rate of population increase. Considering this and the low catch levels in surveys and fisheries, Norwegian Skate is suspected to have declined by nearly 30% over the past 30 years (three generation period).

habitat:
This benthic and benthopelagic species is found on slopes and submarine rises at 200 m to > 1,000 m depth (Stehmann and Bürkel 1984, Stehmann 1990), but little is known about its biology. This is one of the largest European skates with a maximum total length of at least 230 cm (Ebert and Stehman 2013). Like other skates, it is an egg-laying species. The species is inferred to have an estimated generation length of 10 years.

threats:
This skate is not targeted by commercial fisheries, but it is occasionally taken as bycatch in deepwater trawl and longline fisheries. It is usually discarded when caught incidentally, therefore landings data are limited and of variable quality (ICES 2012). It accounted for 1% of skates recorded in biological sampling in Irish ports between 2001 and 2007 (ICES 2007). This is a large skate with low productivity and high catchability, similar to other large skates that have been significantly affected by even moderate levels of bycatch (Dulvy and Reynolds 2002). Deepwater fisheries, including crustacean trawl fisheries, are known to operate within its range. Given this species’ high vulnerability and suspected declines from some areas of the shelf margin, it should be closely monitored

conservationAction:
No species-specific management or conservation measures are currently in place. In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for all skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 825% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (19992014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VIIX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).In future, the status of this species needs to be monitored appropriately. Efforts should be made to collect reliable species-specific catch data and fisheries-independent data for this species. Besides, further research should be conducted on the population size, trend, taxonomy and harvest of the species.

useAndTrade:
This skate is not targeted by commercial fisheries, although it is taken as bycatch.

redListAssessors:
Stehmann, M.F.W., Ellis, J., Walls, R. & Lynghammar, A.

redListContributors:
Duffy, C.A.J., Ebert, D.A. & Stenberg, C.


taxonomicNotes:
There is a possibility that this species is a complex, similar to the Dipturus batis-complex (Iglesias et al. 2010), but further taxonomic work is required.

redListCategoryRationale:
Longnosed Skate (Dipturus oxyrinchus) is a demersal species found on sandy or muddy bottoms at depths of 90−900 m. The large body size and inferred low intrinsic rate of population increase suggests that this skate will be highly sensitive to exploitation. Two genetically distinct subpopulations exist in the Mediterranean Sea and Northeast Atlantic. In the Northeast Atlantic, the depth range of this species extends down the continental slope to 900 m, but it is rarely encountered on the outer continental shelves. There are limited data on occurrence in Norwegian waters, the Faroes Grounds and the French and Iberian Atlantic shelves but nothing is known of current population trends in the Northeast Atlantic region. Historically, this species may have been more widely distributed in shelf areas. In the Mediterranean Sea, this species is found at depths > 200 m and is most frequently captured at depths of 200−500 m in research surveys. It is moderately abundant in the central and eastern Mediterranean Sea, but is now absent from the west. While there has been no indication of a decline in abundance for the last 20 years in Italian waters, it has been absent from research surveys from the Gulf of Lions since 1984 and it is now rarely captured in the shelf areas of the Adriatic Sea. The species is assessed as Near Threatened as, considering the status of other Dipturus species in the European region, the low catch levels in surveys and fisheries and the slow life history of the species, D. oxyrinchus is suspected to have declined by nearly 30% over the past 30 years (three-generation span), therefore being close to qualify as threatened under criterion A2bd. Further research is required to understand the taxonomic and population status of this species in both areas and management and monitoring are required.

range:
In the Northeast Atlantic this skate occurs on the outer continental shelf and continental slope from central Norway southwards (Heintz 1962, Stehmann and Bürkel 1984). It is found in the Barents Sea, in the Norwegian Sea mainly along the coastline south of latitude 65°N, and in very low numbers in the North Sea (Williams et al. 2008, ICES 2012). The species was last encountered in trawl surveys around the Faroe Islands in 2001, and is only occasionally caught on the Rockall Survey in offshore waters west of Scotland (ICES 2012). In the Bay of Biscay, Iberian waters, and the Azores and mid-Atlantic ridge, it is still encountered by fisheries and trawl surveys in low numbers. This skate was historically found throughout the Mediterranean Sea in both shelf and slope areas (Stehmann and Bürkel 1984), with the greatest survey catches occurring around the Corsica, Sardinia and Malta Islands, and throughout the eastern part of the basin including Dodecanese waters. By contrast it is not present in the western Mediterranean Sea, along the French and Spanish coasts, and the Northern Adriatic Sea (Serena et al. 2011). Its depth range is 90-900 m.

population:
Two genetically distinct subpopulations exist in the Mediterranean Sea and the Northeast Atlantic.Northeast AtlanticLittle is known of the subpopulation status or trends in abundance in the Northeast Atlantic, but it is suspected to have declined or contracted in range. Between the late 1960s and 2002 United Kingdom groundfish surveys occasionally reported this species in the northern North Sea and Celtic Sea at depths of 111159 m. Catch rates over this time period were very low ranging between 0.01 and 0.11 individuals captured per hour of trawling (Ellis et al. 2005). In the Annual Autumn Bottom Trawl Surveys of the northern Norwegian Coast, 54 individuals were reported in 1994, and only two individuals were reported in 2005 (Williams et al. 2008). Along the northern coast of Norway from 19922005, Williams et al. (2008) caught a mean of 7.7 individuals per square kilometre. The catches in this study were relatively high, indicating that although the species is somewhat rare, local aggregations may occur. In and around the Bay of Biscay catches showed large fluctuations, ranging from zero tonnes in 1999, to 16 tonnes in 2002, and decreasing again to zero tonnes in 2010 (ICES 2012). Although information is limited, the sensitive life history characteristics and available data suggest that this subpopulation is declining in Northeast Atlantic waters.Mediterranean SeaIn the Mediterranean, the International Trawl Survey in the Mediterranean (MEDITS) preformed 6,336 tows between 1994 and 1999 over the entire European Mediterranean area and Morocco at a depth of 10800 m. This species was the second most abundant skate in this survey and was recorded in 3% of hauls in this area. It was found at depths ranging from 50 to 800 m, but was caught most frequently between 200 and 500 m in the western central Mediterranean Sea and eastwards in the Aegean Sea (Baino et al. 2001, Serena 2005, Serena et al. 2010). A longline survey in 2004 confirmed the presence of this species in the southeast Aegean Sea, around Rhodes between 300 and 400 m depth (Corsini-Foka 2009). This species was historically present in the Gulf of Lions, northwest Mediterranean Sea, where it was captured in 10% (n=27) of hauls, occurring between 1959 and 1972 (coast to 150 m depth) and was also present in the catches of surveys performed between 19801984. It was subsequently absent from 628 scientific tows done in the same area in the period 19851995 (Aldebert 1997). Similarly, in the Adriatic Sea, historical trawl surveys from 1948 showed that this species was present in 3.2% of hauls carried out on the continental shelf, while in a comparable MEDITS survey in 1998 reported that this species was absent from all hauls on the continental shelf (Jukic-Peladic et al. 2001). In the south Ligurian and north Tyrrhenian Seas this species has been found at depths ranging from 164750 m, and was mostly concentrated on the outer margin of the slope from 300400 m. Over this survey period, biomass has reportedly decreased while abundance remained stable. This suggests a change in population structure, with an increasing presence of juveniles in catches. Given the sensitive life history characteristics, evidence of significant population declines and apparent disappearance in some localised areas (likely due to fisheries pressure), this subpopulation is considered to be decreasing throughout the Mediterranean Sea.Considering the status of other Dipturus species in the European region, D. oxyrinchus is also inferred to be in decline, although to a lesser extent due to its smaller size, and it is suspected that the species has declined by nearly 30% over the past 30 years (three-generation span).

habitat:
This demersal skate is found on sandy or muddy bottoms at depths ranging from 90900 m, and appears to be most abundant from 200500 m (Stehmann and Bürkel 1984, Baino et al. 2001).This egg laying skate has a spawning period from February to May (Stehmann and Bürkel 1984, Bauchot 1987, Notarbartolo di Sciara and Bianchi 1998, Serena et al. 2010), and produces egg cases between 10 and 15 cm in length. Size at birth is 17 cm total length (TL; Ebert and Stehmann 2013). Estimated length at 50% maturity was 83.2 cm TL for males and 104.4 cm TL for females (Serena et al. 2011). Both sexes are estimated to reach sexual maturity between six and eight years. Stehmann and Bürkel (1984) reported a maximum size of 150 cm TL. The generation length of this species is inferred from that of Barndoor Skate (which is slightly larger) to be around 10 years.

threats:
This is one of the larger bodied species of skate and it is thought to have declined from shelf areas, although this would be the shallower fringe of the bathymetric distribution. The large body size (150 cm), and presumably slow growth and later maturation and likely low intrinsic rate of population increase of this species render it especially vulnerable to exploitation such as trawling and at risk of local extinction (Walker and Hislop 1998, Dulvy et al. 2000, Dulvy and Reynolds 2002).Northeast AtlanticThere are no specific data available on threats, however it is inferred that, similar to other large-bodied skates, this species may be retained as bycatch in demersal trawl and longline fisheries, particularly in deeper waters. Although only large individuals may be landed for consumption, most size classes are likely to be taken in fishing nets. This species is caught and landed from offshore fisheries as reported by the United Kingdom, but data are unreliable. These landings are likely the result of misidentification or incorrect use of species codes (ICES 2012). Given recent restrictions on landing other members of this genus, recent data indicating increasing catches of this skate are questionable due to possible reporting of other species as Longnosed Skate (Dipturus oxyrinchus; ICES 2013). Mediterranean SeaThis skate is captured as bycatch in bottom trawl fisheries targeting Norway Lobster (Nephrops norvegicus) or Red Shrimp (Aristeus antennatus) and by offshore bottom longlines. Over the last 50 years, trawl effort has increased numerically and technologically in the shelf and slope area of the Mediterranean Sea. For example, the Gulf of Lions area was historically exploited by small-scale benthic trawl fisheries composed of 27 small, low-powered boats with a total of 2,700 horse power (hp), between 1974 and 1987 effort has increased to a total of 19,940 hp. In particular, fishing effort targeting small pelagic fish has increased (Aldebert 1997). The Adriatic Sea is subject to trawling by Italian, Croatian, Slovenian, and Albanian fleets, however, no landings data are available (Jukic-Peladic et al. 2001). The General Fisheries Commission for the Mediterranean (GFCM), the main intergovernmental decision-making body on fishery management in the Mediterranean Sea, has made the decision to refrain from expanding deepwater fishing operations beyond the limit of 1,000 m. However this species occurs mostly from 200-500 m, thus deepwater fisheries development within the depth range of this species remains a cause for concern.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).Further research should be conducted on the population size and trend of the species.

redListAssessors:
Ellis, J., Abella, A., Serena, F., Stehmann, M.F.W. & Walls, R.

redListContributors:
Ungaro, N., Tinti, F., Bertozzi, M., Mancusi, C., Notarbartolo di Sciara, G. & Fordham, S.


taxonomicNotes:
Formerly called Raja circularis. Early papers often confused Leucoraja circularis and Leucoraja naevus.

redListCategoryRationale:
Sandy Skate (Leucoraja circularis) is a relatively large species found in the Northeast Atlantic and Mediterranean Sea. Historically it was found around 100 m depth on sandy and muddy bottoms, though it is now mainly found in slightly deeper waters along the edge of the continental shelf and upper slope. It is taken as bycatch in multi-species trawl fisheries and offshore bottom longlines. In the Northeast Atlantic, landings and catch rates for this skate have declined since the early 1990s. The species has completely disappeared from trawl surveys in the North Sea and Celtic Seas in 1996 and 1997, respectively. Scottish surveys still catch it around northwest Scotland and the Porcupine Bank, but at greater depths (180–500 m) than historically reported. This suggests a contraction of the species’ range as a result of trawl fisheries. Records from the outer shelf are scarce, and while survey catch rates have been stable for this species now in the areas it has been considered most abundant since 2001, these rates are very low, therefore do not imply population stability. Misidentification has also prevented reliable estimates of population decline, potentially masking the disappearance of this species from certain areas. For example, Belgium and France are still suspected to be misreporting the species in confusion with Smalleyed Skate (Raja microocellata). Given the paucity of records from the outer continental shelf, the large declines in landings in recent years, the contracted range to deeper waters, and the very low catch levels seen in the Porcupine Bank survey, Sandy Skate is suspected to have largely in the declined Northeast Atlantic. Fishery independent data for mature individuals are limited and careful monitoring of subpopulations across its range is required to determine accurate population trends for mature individuals.In the Mediterranean Sea, the occurrence of this species has decreased in the last 60 years. It is no longer encountered in the Gulf of Lions or the Adriatic Sea where it was once relatively common. Mediterranean-wide scientific trawl surveys from 1995–1999 recorded this species in only 12 of 6,336 trawls. Benthic trawl effort has increased significantly during the last 60 years and fishing pressure continues within this species’ depth range. Given the current rarity of Sandy Skate in the Mediterranean Sea, evidence of potential local extinction from two locations, and its likely low intrinsic rate of increase suggested by its large body size and large size at maturity, together with the declines suspected on the Northeast Atlantic, the species is suspected to have declined overall by more than 50% in the last three generations (29 years). Thus, the species is assessed as Endangered.

range:
Given the lack of authenticated records, the exact range of this species is uncertain. In the Northeast Atlantic, it is found in the Norwegian Sea and northern parts of the North Sea, but has not been encountered around the Faroe Islands since prior to 1996 (ICES 2012). It occurs throughout deeper waters west of Ireland and Britain, with the occasional vagrant found in the Celtic Sea. The species is also still landed from the Bay of Biscay and Iberian waters. This skate was once present throughout the western Mediterranean Sea and as far east as Libya. It is absent from the Black Sea (Stehmann and Bürkel 1984, Bauchot 1987, Notarbartolo di Sciara and Bianchi 1998, Relini et al. 2000, Ragonese et al. 2003, Sion et al. 2003, Serena 2005, Serena et al. 2011), and now considered absent from the Adriatic Sea (Ferretti et al. 2013). Its depth range is 50-800 m.

population:
There are two subpopulations of this species, with different situations for the Northeast Atlantic and Mediterranean Sea. It is likely that there is low connectivity between these two deepwater zones. The overall trend in European waters is of a decline.Northeast AtlanticThis species is rare in the Northeast Atlantic. Accurate determination of abundance trends over the broader area are not possible, as most earlier surveys have focused on shelf fishing grounds, with no long-term, standardised surveys sampling off the edge of the continental shelf. In the southern Northeast Atlantic, French landings data for this species have shown a decline of 92% over about 20 years, from about 500 tonnes per year in the early 1990s to less than 40 tonnes in 2012. French and Portuguese landings data from the Bay of Biscay and Iberian waters across all gears combined have remained low but stable between 1999 and 2011, ranging from around 16–17 tonnes at the beginning and end of the time series, with a peak of 61 tonnes in 2005 (ICES 2012). Again, these data are potentially inaccurate owing to misidentification.In the northern area of the Northeast Atlantic, English surveys in the North and Celtic Seas have not recorded this species since 1996 and 1997 respectively, although Scottish and Norwegian surveys have recorded it in various surveys around Scotland and along the north coast of Norway since then. Given the low numbers caught in offshore shelf habitats, it is possible that the main part of the range is now in deeper water, such as along the edge of the continental shelf. Indeed, most of the recent captures of this species in Scottish surveys have been from waters of 180–500 m depth. In the Norwegian Sea, the Annual Autumn Bottom Trawl Survey on the north coast of Norway did not report any catches of this skate from 1992 to 2000. From 2000 to 2005 it was encountered in very low numbers (zero to nine individuals per survey), showing no particular trend in abundance (ICES 2012). Given the decline in French landings, and that the range has contracted to deeper waters in the Scottish surveys, it is assumed that the population has declined throughout the Northeast Atlantic. There is uncertainty over the magnitude of the decline in abundance for the population as a whole, owing to the lack of reliable data.Throughout waters west of Britain and Ireland, the Spanish Porcupine Bank survey (on the western Ireland continental shelf) is the only survey that covers the Northeast Atlantic continental shelf, an important part of this species’ range. This survey recorded peak catches in 2003 and 2007, yet this limited time series has low (e.g., about 0.6 kg per haul in 2011) and variable catch rates, with a stable trend in recent years (ICES 2012). Historically, this species may have been more widely distributed in shelf seas west of Britain and Ireland. It is now encountered rarely in surveys on the inner continental shelf, but still exists in deeper waters along the edge of the continental shelf. Given the reported decreases in survey and landings data, the Northeast Atlantic subpopulation is estimated to be declining.Mediterranean SeaThe occurrence of this species in the Mediterranean Sea has decreased significantly over the last 60 years. It was present in shelf and slope trawl surveys in the Gulf of Lions between 1957 and 1960 but was absent from more recent comparable surveys. Between 1957 and 1960, it was captured in more than 10% of hauls in shelf surveys and in approximately 17% of hauls in slope surveys, whereas between 1966 and 1995 it was not recorded at all from 1,295 hauls in eight trawl surveys (Aldebert 1997).The International Trawl Surveys in the Mediterranean (MEDITS) cover the northern Mediterranean coast almost continuously, from west Morocco and Spain in the west to the Aegean Sea in the east (Baino et al. 2001). Six trawl surveys were carried out each year in the coastal areas of four arbitrary geographically defined areas: Western (Morocco, Spain, France), Western Central (Tyrrhenian, Corsican, Sardinia and Sicily coasts), Eastern Central (Adriatic, Ionian and Albanian coasts) and Eastern (Aegean Sea). A total of 6,336 tows were completed between 1994 and 1999 at depths ranging from 10 to 800 m. This skate was recorded in only 12 hauls, all in the western area of the Mediterranean Sea (Baino et al. 2001). The evidence that this species may now be scarce in the western Mediterranean Sea points to a substantial reduction in area of occurrence. Its depth range also appears to have contracted, as it was previously found on shelf and slope bottoms between 70 and 275 m (mainly at around 100 m), but is now found only in deeper waters between 500 and 800 m (Baino et al. 2001). The overall biomass index assessed through MEDITS in the west, north and eastern Mediterranean Sea was 0.1 kg per km2 (Baino et al. 2001).Other records in the Mediterranean also show a decline in capture rates. In the south Ligurian Sea and north Tyrrhenian Sea this species is considered rare based on low capture rates. From 1985–2005 only 10 specimens were caught in the bathyal zone (352–566 m depth) (Serena et al. 2005). In 1948, it was recorded in 3.2% of trawl samples from the Adriatic Sea but has been absent from all trawl survey data in this area since then (Ferretti et al. 2013). It can be inferred that the Mediterranean subpopulation is decreasing given reported declines in capture rates from trawl survey data.In European waters, the species is suspected to have declined overall by more than 50% in the last three generations (29 years).

habitat:
This benthic skate occurs in offshore shelf waters and on upper slopes from 50–800 m depth. Historically it was found around 100 m depth on sandy and muddy bottoms, although it now seems more abundant in deeper waters where habitat preferences are currently unknown.This species is oviparous with egg cases 88–90 by 50–60 mm (Stehmann and Bürkel 1984, Mnsari et al. 2009). The spawning period is unknown (Bauchot 1987, Notarbartolo di Sciara and Bianchi 1998). Maximum recorded size is 120 cm total length (TL), but most individuals caught are between 70 and 80 cm TL (Serena 2005, Ebert and Stehmann 2013). Age at maturity, longevity, size at birth, reproductive age, gestation time, reproductive periodicity, fecundity, rate of population increase and natural mortality are unknown. Its congener L. naevus has a generation lengh of 9.7 years based on a longevity of 12 years, and an estimated age at maturity of 6.8-7.4 years. Thus, the generation length of L. circularis is also 9.7 years.

threats:
Northeast AtlanticThis species is a bycatch in multi-species trawl fisheries operating in the outer parts and edge of the continental shelf. It may also be taken as bycatch in gillnet fisheries targeting anglerfish and longline fisheries targeting hake, though data on the catches in these fisheries are poor. If deepwater commercial fisheries expand into this species’ range they could pose a threat, although there is currently no indication of such expansion. European deepwater fisheries have decreased since 2008, but their effort and extent should be monitored. The relatively large body size would also indicate that it is vulnerable to overfishing. Due to its offshore habitat, it is of no importance to recreational fisheries.Belgium and France are thought to still record Smalleyed Skate (Raja microocellata) landings erroneously as landings of this species, owing to the shared common name, ‘Sandy Ray’, which hampers the interpretation of some data (ICES 2012).Mediterranean SeaThis skate is a bycatch in multi-species trawl fisheries and offshore bottom longlines. Demersal trawl effort has increased both numerically and technologically in the shelf and slope area of the Mediterranean Sea over the last 50 years. For example, the Gulf of Lions area was initially exploited by small-scale benthic trawl fisheries comprising 27 small low powered boats with a total nominal horsepower of 2,700 hp. More recently effort has increased to a total of 19,940 hp (1974–1987) and more than half of the fishing effort has been displaced to target small pelagic fish (Aldebert 1997). The Adriatic Sea is subject to trawling mainly by Italian, Croatian, Slovenian, and Albanian fleets, however, no landings data are available (Jukic-Peladic et al. 2001). Although little is known of the life history of this species, it is presumed from similar species that it is slow growing with low fecundity and large juveniles, making it especially vulnerable to fishing exploitation (Brander 1981, Walker and Hislop 1998, Dulvy et al. 2000, Dulvy and Reynolds 2002). Moreover, although only large individuals may be landed for consumption, most size classes including the egg cases are caught in fishing nets, as the legal mesh size used in much of the Mediterranean Sea is about 20 mm. Currently, the contents of the cod end are retained and the 20 mm mesh size commonly used in the Mediterranean Sea means that all life stages of this species are fished.The main intergovernmental decision-making body on fishery management in the Mediterranean Sea, the General Fisheries Commission for the Mediterranean (GFCM), has made the decision to refrain from expanding deepwater fishing operations beyond the limit of 1,000 m. This is still within the range of this species, as it is not known to occur below 800 m.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea and North Sea (International Council for the Exploration of the Sea [ICES] Division IIa and Subarea IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (1999–2014), the TAC was higher than reported landings and therefore was not effectively managing catches. In 2009, skate and ray TACs were established for other EU waters, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and Northern Ireland to Portuguese waters (ICES Subareas VI–IX) and have also been gradually reduced each year.In 2006, the European Commission (EC) imposed a permanent ban on all deepwater gillnet fisheries operating at depths greater than 600 m, and imposed maximum limits on the length of nets deployed and the soak time in the remaining fisheries at depths less than 600 m (EC Regulation No. 41/2006). These restrictions may have been of some benefit to this skate. Additionally, since 2008 the EC obligated member states to provide species-specific landings data for the major North Sea species, including this species, in order to improve understanding of skate populations in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Sea (CEC 2009), and has been ongoing since 2008 (CEC 2013).This skate was listed in Annex III of the Barcelona Convention in 2012, therefore any event of incidental catch and release should be recorded by masters of fishing vessels in the fishing logbook referred to in Article 14 of Regulation (EC) No 1224/2009, in Mediterranean waters.Moving forward, this species may benefit from more generic management measures for demersal fisheries, for example mesh size regulations and effort reduction. Appropriate non-trawling areas should be defined to protect a proportion of both the adult population and this skate’s eggs (which are often found in the trawl cod-end) (Ragonese et al. 2001). Further research should be conducted on the population size and trend of the species.

useAndTrade:
Large individuals may be landed for human consumption.

redListAssessors:
McCully, S., Ellis, J., Walls, R. & Fordham, S.

redListContributors:
Ungaro, N., Serena, F., Dulvy, N., Tinti, F., Bertozzi, M. & Notarbartolo di Sciara, G.


redListCategoryRationale:
Shagreen Skate (Leucoraja fullonica) is an offshore species, usually occurring on the outer parts of the continental shelf, at depths of 30–550 m, and it has occasionally been recorded beyond 550 m in the Mediterranean Sea. In the Northeast Atlantic this skate is taken as bycatch in demersal trawl and longline fisheries throughout much of its range. Reported French landings were more than 370 tonnes in 1983, but since 1984 annual landings have been more stable and averaged about 75–150 tonnes. Recent captures of this species in Scottish surveys have been made in waters > 200 m deep, suggesting that its range has been constricted to deeper waters. However, accurate trends in abundance are hard to determine due to changes in survey techniques, as well as some uncertainty in the taxonomic identification in earlier surveys. It is suspected that there have been continuing population declines of 30-50% over three generations for the Northeast Atlantic subpopulation.   Few data are available on this skate in the Mediterranean Sea, where it was recorded in only seven of 6,336 tows between 1994 and 1999 at depths ranging from 10–800 m during the International Trawl Survey in the Mediterranean. More recent records from 2008–2009 identified ten specimens in the southern Adriatic Sea, an area that this species was previously suspected to be absent from, although these records could be misidentifications. This species is rare in Mediterranean trawl surveys. However, this skate likely has a low intrinsic rate of increase suggested by its large body size and large size at maturity. Therefore, further analyses of survey data and close monitoring are needed to elucidate the long-term distribution and relative abundance of this species.It is assumed that the rate of decline in the Mediterranean Sea is at least the same or worse than the NEA due to near absence of effective fisheries management there. Therefore it is inferred that this species meets the threshold for Vulnerable, given an estimated 30-50% overall decline in a three generation span from the NEA (from ICES 2012) and suspected 30-50% decline throughout European waters overall in a three generation span. This species potentially meets the threshold for Endangered and thus should be monitored, particularly in the Mediterranean.

range:
In the Northeast Atlantic this skate occurs in the offshore waters of the continental shelf from Madeira and northern Morocco. Northwards it is present but sparse in the Norwegian Sea including the Skagerrak, Icelandic waters, the Faroe Islands and east of Greenland (Stehmann and Bürkel 1984, ICES 2012). It occurs in low numbers west of Scotland at Rockall Bank, in the Bay of Biscay region, in Iberian waters and around the Azores and mid-Atlantic ridge (ICES 2012). In the Mediterranean Sea it is known from the western and eastern central areas to Tunisia and western coasts of Greece, including the southern Adriatic Sea (Stehmann and Bürkel 1984, Bauchot 1987, Bertrand et al. 2000, Relini et al. 2000, Marano et al. 2003, Tinti et al. 2003, Serena et al. 2011).

population:
It is likely that there is poor connection between the two deepwater subpopulations of the Northeast Atlantic and Mediterranean Sea. The overall population trend of this species is of a decrease.Northeast AtlanticAccurate determination of abundance trends in the Northeast Atlantic is not possible, in the absence of long-term, standardised surveys sampling off the edge of the continental shelf. Historically, this species may have been more widely distributed in shelf areas in the Northeast Atlantic. Reported French landings for this species were more than 370 tonnes (t) in 1983, but since 1984 annual landings have been more stable and averaged about 75–150 t. English surveys in the North Sea have not recorded this species since 1998, though occasional specimens are taken in the Celtic Sea. It is now encountered only infrequently in surveys on the inner continental shelf, though is still present in deeper waters along the edge of the continental shelf, suggesting that the main part of the range has contracted to deeper water. Indeed, most recent catches in Scottish surveys have been made in waters deeper than 200 m.Catches of this skate around Iceland and eastern Greenland has been relatively stable overall, ranging from two tonnes in 1993 to 17 t in 2011, with the highest catch of 37 t recorded in 2001 (ICES 2012). While these catch volumes are low, confusion with Sailray (Rajella lintea) is believed to still occur, suggesting that true catch volumes may be even lower. The French Evaluation Halieutique Ouest Européen (EVHOE) Groundfish survey suggested an overall declining trend in abundance and biomass in waters west of Scotland and Ireland between 1997 and 2011, although this decline appeared to be stabilizing in 2010–2011 (ICES 2012). French landings from the Bay of Biscay and Iberian waters have increased from three tonnes in 2000 to 32 t in 2011 (ICES 2012). Spanish landings from this region have been consistently low and stable, ranging from four tonnes in 2000 to eight tonnes in 2008. Purported Scottish landings of White Skate (Rostroraja alba) from these waters may also refer to Shagreen Skate (Leucoraja fullonica) because White Skate is considered depleted in this area (ICES 2013). Although levels of exploitation are unknown for this subpopulation, it is inferred to be declining due to a decrease in survey catch rates and landings.Mediterranean SeaThis species was captured at depths ranging from 200–800 m in only seven of 6,336 tows during the International Trawl Survey in the Mediterranean (MEDITS) performed throughout the northern Mediterranean Sea from 1994–1999 in depths ranging from 10–800 m (Baino et al. 2001). It was absent from multiple trawl survey time series data that ran from 1957–1995 and consisted of eight separate surveys conducted by four different survey vessels in the Gulf of Lions in the eastern Mediterranean Sea (Aldebert 1997). Additionally, it was was absent from both recent and historical surveys in the Adriatic Sea (Jukic-Peladic et al. 2001). While further MEDITS surveys from 2008–2009 found ten specimens of the species in the southern Adriatic Sea (Zupa et al. 2010), an area it was previously thought to be absent from, it is possible that these specimens may have been incorrectly identified Sandy Skate (Leucoraja circularis). Trawl surveys in the south Ligurian Sea and north Tyrrhenian Sea suggest that the species is rare there, with few specimens captured between 1985 and 2004 at depths of 366–549 m (Serena et al. 2005). The trajectory of the Mediterranean Sea subpopulation is currently unknown.

habitat:
This benthic skate is found in offshore shelf and upper slope waters on sandy and coarse bottoms, predominantly found around 200 m depth but ranging from 30–800 m (Stehmann and Bürkel 1984, Ellis et al. 2005). In the Mediterranean Sea, it occurs in relatively cold coastal waters and on upper parts of continental slopes in about 30–550 m, but has also been captured in deeper water down to 800 m (Stehmann and Bürkel 1987, Bertrand et al. 2000, Baino et al. 2001). Little is known about the biology and reproductive cycle of this relatively large-bodied skate. It is an egg laying species, producing egg cases that measure about 8 by 5 cm (Stehmann and Bürkel 1984). Specimens caught in the Celtic Seas and North Sea between 1992 and 2011 ranged from 21 to 96 cm and 24 to 70 cm total length (TL) in males and females, respectively (McCully et al. 2012). All female specimens were immature, while only two males at 75 and 96 cm TL were mature. The largest immature male caught was 82 cm TL. This species reaches a maximum size of 100–110 cm (Bauchot 1987). Based on the information available for its congener, L. naevus, the species has an estimated generation length of 9.7 years.

threats:
The relatively large body size of this skate suggests that it is sensitive to exploitation. It is taken as bycatch in mixed demersal fisheries through much of its range, including mixed trawl fisheries operating in the outer parts and edge of the continental shelf in both the Northeast Atlantic and the Mediterranean Sea. In the Mediterranean Sea it is also caught as bycatch by both bottom trawl and longline fisheries (Stehmann and Bürkel 1984, Serena 2005). In the Northeast Atlantic it may also be taken as a bycatch in gillnet fisheries targeting anglerfish and longline fisheries targeting hake, though information on the catches in these fisheries are poor. 

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 t for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Additional management measures, including a 2006 permanent ban on all deepwater gillnet fisheries at depths of > 600 m imposed by the European Commission (EC), may help to protect the deeper range of this species. The EC also imposed maximum limits on the length of nets deployed and the soak time in the remaining fisheries at depths of < 600 m (EC Regulation No. 41/2006). Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and Northern Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 t (regulations are available online at http://faolex.fao.org). Since 2008, the European Commission has obliged member states to provide species-specific landings data for the major North Sea species, including this species, in order to improve understanding of skate stocks in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009), and has been ongoing since 2008 (CEC 2013). Additional management measures, including non-trawling areas in the Mediterranean Sea, could benefit this species as a fraction of the adult population and eggs are often found in trawl cod-ends (Ragonese et al. 2003).

redListContributors:
Serena, F., Dulvy, N., Ungaro, N., Tinti, F., Bertozzi, M., Pasolini, P., Notarbartolo di Sciara, G. & Fordham, S.


taxonomicNotes:
The subgenus Leucoraja was elevated to genus rank by McEachran and Dunn (1998).

redListCategoryRationale:
Maltese Skate (Leucoraja melitensis) is a demersal species that is endemic to the Mediterranean Sea. Historically, this species was moderately common off Tunisia and Malta, and rare off France, Algeria and Italy. It now appears to be mostly restricted to one small part of the Mediterranean Sea, the Sicilian channel around Malta Island, which is subject to heavy trawling activity. In the 1990s, surveys no longer detected this skate in the Gulf of Lion. It was extremely rare in the western central Mediterranean Sea (the coasts of Tyrrhenia, Corsica, Sardinia and Sicily) according to the International Trawl Surveys in the Mediterranean from 1994 to 1999 (i.e., recorded in 20 of 6,336 hauls). It is now more rare off Malta and rare or absent off Tunisia. Maltese Skate is assessed as Critically Endangered under criteria A2bcd+3bcd as a result of a suspected population size reduction of at least 80% over a three generation period (15 years), based upon its endemism to the region, inferred reduction in the area of occupancy, and inferred population reductions off the Maltese, Tunisian and French coasts. The population is also suspected to continue declining around 80% in the future over the period of three generations. More research is needed on its range, biology, ecology, exploitation, and abundance.

range:
The species is endemic to the Mediterranean. Its range now appears to be restricted to the Sicilian Channel around Malta (GFCM 2012). The depth range is 60800 m, but it is most commonly found between 400800 m.

population:
This is one of only four skate species endemic to the Mediterranean Sea, and has undergone significant declines and a reduction in its geographical range. Historically, its range once extended over about one quarter of the total area of the Mediterranean Sea (at least within the depth range of the main trawl fisheries). It was moderately common off Tunisia, common around Malta, rare off Algeria and recorded once off Italy (Stehmann and Bürkel 1984). The range of this skate now appears to be restricted to the Sicilian Channel (Pipitone et al. 1992, Relini 1995, Cannavò et al. 1999), and it is considered rare off Malta (Schembri et al. 2003) and rare or absent off Tunisia (Bradaï 2000). In Italian waters, trawl surveys performed by Gruppo Nazionale risorse Demersali (GRUND) between 1985 and 2000 only recorded this species in the Sicilian Channel (20 of 23 hauls in this area; Relini et al. 2000, Ragonese et al. 2003).In surveys conducted in the northern Mediterranean Sea from the Alboran to Aegean Sea (including off Sicily), the International Trawl Survey in the Mediterranean (MEDITS) recorded this species in only 20 out of 6,336 hauls between 1994 and 1999 (Bertrand et al. 2000, Baino et al. 2001). In this area, the standing stock biomass of this species was estimated to be 705 tonnes. If the average weight of an individual is ~2 kg, the estimated population size in the MEDITS survey area was ~35,200 individuals at this time (note that this does not include any remaining population around Malta and North Africa).Records from surveys of the Gulf of Lion infer that this species was present on the continental shelf in 19571960 and slope in 19801984, but not in comparable surveys carried out in 19921995 (Aldebert 1997). However, caution should be taken with these findings because the species could be confused with Cuckoo Skate (Leucoraja naevus), which is widespread in the western part of the Mediterranean Sea.In a recent study, bottom trawl hauls of commercial vessels operating in the Aegean Sea were analysed three times per year from 1995 to 2000 and 2003 to 2006 (Damalas and Vassilopoulou 2011). A mean nominal catch per unit effort declined by 50% in the number of individuals (from 0.22 to 0.11 individuals per haul) and by 60% in weight (from 0.05 to 0.02 kilograms per haul) between the two time frames. The last encounter with this species in the Adriatic Sea was a single individual recorded during bottom trawl surveys in 2005 (Ferretti et al. 2013).A decline of at least 80% of the population is suspected in European waters based on the fact that it has disappeared from over 80% of its former range over a 15 year period.

habitat:
This benthic skate occurs over sandy and sandy-muddy bottoms at depths of 60800 m, but most commonly 400800 m.Little is known about the reproductive cycle of this skate. Breeding occurs throughout the year, though ovulating females have mainly been observed in the spring and autumn (Stehmann and Bürkel 1984, Serena 2005). Females produce 1056 eggs per year (Bauchot 1987). Both males and females mature at ~40 cm total length (TL; Bauchot 1987, Notarbartolo and Bianchi 1998), and the maximum reported size is ~50 cm TL (Stehmann and Bürkel 1984). In Italian waters, the size range of this species was reported to be 942 cm TL between 1985 and 2001 (Ragonese et al. 2003). Its generation length is suspected to be 4-5 years.

threats:
The majority of this species’ geographic (i.e., in the Sicilian Strait around Malta) and depth (400800 m) range occurs where trawling activity is intensive. The Sicilian Channel is the most exploited region of the Italian coast with respect to the total number of fishing vessels of any kind compared to other parts of the basin. Most of the fleet is composed of multipurpose artisanal vessels using bottom longlines, gillnets and trammel nets, all gear types that are likely to catch this species. Trawl fishing vessels constitute 11% of the fleet (Relini et al. 2000). While this skate is not known to be targeted by commercial fisheries, it is taken as bycatch in bottom trawl, gillnet, and bottom longline fisheries and often discarded (Ragonese et al. 2003). Skates generally have low commercial value in the Mediterranean region, but occasionally this species is present in fish markets. Usually only the large individuals are landed for human consumption, however, there is full retention of all size classes in the cod-end of gears currently used, regardless of mesh size (Ragonese et al. 2001).Along the Tunisian coast, this species is occasionally caught as bycatch in bottom trawl, gillnet, and bottom longline fisheries, but it is now extremely rare in this area (Bauchot 1987). Maltese fisheries using bottom longline and trawl gear may take this species as bycatch (De Leiva et al. 1998), although Maltese fishing fleets are smaller to those of the Italians’. Tunisian fisheries are small, coastal and probably operate outside this species’ area of occurrence (Samira 2002).Benthic trawling effort over the continental shelf and slope in the Mediterranean Sea increased with respect to fishing effort and technological advances over a period of 60 years, although it is unclear if fishing effort will continue to increase within this species range. Fishing effort and catches should be monitored closely.

conservationAction:
According to the Fisheries and Aquaculture Organisation’s (FAO) International Plan of Action on the management and conservation of sharks (IPOA-Sharks), all states that capture sharks, rays, skates or chimaeras, either as target species or as bycatch, shall implement national action plans to ensure suitable use, conservation and recovery of threatened species (Vacchi and Notarbartolo 2000).In 2012, parties to the Barcelona Convention agreed that this species (as listed in Annex II of the Specially Protected Areas and Biological Diversity (SPA/BD) Protocol for the Mediterranean Sea) cannot be retained on board, transshipped, landed, transferred, stored, sold, displayed or offered for sale, and must be released unharmed and alive, to the extent possible, in the Mediterranean Sea (FAO 2012). Furthermore, the Italian National Action Plan was drafted by the Central Institute for Marine Research (ICRAM) scientific advisory committee to provide Italy with tools needed to ratify the SPA/BD Protocol (Serena et al. 2002, Vacchi and Notarbartolo 2000). The European Commission also drafted a proposal for the European Community Plan of Action that encourages research programs aimed at the assessment of the conservation status of cartilaginous fishes in the Mediterranean Sea (Serena et al. 2002).Italy should act urgently to establish a plan of action for the conservation and management of chondrichthyans. To mitigate the decline of this species caused by fisheries bycatch, it is recommended that opportunities to ban trawling in specific areas of the Mediterranean Sea be explored. Mesh size restrictions are unlikely to be effective given that full retention in the cod-end of trawling gear is expected for mesh sizes ranging from 16 to >60 mm (Ragonese et al. 2001). The most appropriate management measure may be to define areas of suitable habitat for this species that are also unsuitable for bottom trawling and close them to trawl fisheries in order to protect part of the population and the eggs from exploitation (Ragonese et al. 2003).

redListContributors:
Ungaro, N., Serena, F., Tinti, F., Bertozzi, M., Pasolini, P., Mancusi, C. & Notarbartolo di Sciara, G.


taxonomicNotes:
This species was previously referred to as Raja naevus. Early papers often confused Cuckoo Ray with Sandy Ray (Lecoraja (Raja) circularis).

redListCategoryRationale:
This small-bodied skate is relatively widespread and endemic to the Northeast Atlantic and Mediterranean Sea. It occurs at depths between 20 and 500 m, and is more common at about 200 m in the Mediterranean Sea. It is taken as bycatch in mixed demersal fisheries through much of its range and used in some areas. It is apparently rare in the Mediterranean Sea and has disappeared in some areas, remaining in areas less intensively trawled. It may have some capacity to withstand moderate fishing pressure compared with larger skates that are highly sensitive to rapid depletion as a result of their limiting life-history characteristics.Abundance trends from the Northeast Atlantic are inconsistent as there is considerable spatial and temporal variability in catch. This species seems to have increased in some areas following previous declines, while in other areas the opposite pattern is seen.However the total Northeast Atlantic population is not considered to have declined significantly. However, there have been observed declines in heavily trawled areas of the Mediterranean Sea, although there are other areas where it is less heavily fished, and there is a lack of new information on trends. Based on the apparent ability of this skate to withstand higher levels of fishing than other larger elasmobranchs, and the lack of negative trend data throughout the majority of its European range, the species is assessed as Least Concern. More information on stock identity is required, and the status of stocks in those areas where it is exploited most in the Northeast Atlantic (e.g., Celtic Sea and Bay of Biscay) need to be better assessed and monitored.

range:
From the Northeast and Eastern Central Atlantic, Cuckoo Skate (Leucoraja naevus) occurs off coasts northward from the Shetland Isles and southern Norway in the north, to Morocco in the south (Stehmann and Bürkel 1989). It is common in the North Sea ecoregion, especially in the northwest area and occurs in low numbers around the Faroe Islands. It occurs throughout the Celtic Seas, including the Irish Sea, outer Bristol Channel, and outer western English Channel. In the Spanish survey of Porcupine Bank, west of Ireland, it is found mainly around the central mound of the bank (ICES 2013). In the Mediterranean Sea this skate occurs in northern, western and central-eastern waters, excluding the Adriatic Sea. It has been recorded in waters off Algeria, France, Greece, Italy, Malta, Morocco, Spain (including the Balaeric Islands) and Tunisia (Bauchot 1987, Stehmann and Bürkel 1989, Bertrand et al. 2000, Relini et al. 2000, Baino et al. 2001, Jukic-Peladic et al. 2001, Tinti et al. 2003, Serena et al. 2011, Valls et al. 2011). Its depth range is 20-500 m.

population:
Northeast and Eastern Central AtlanticThis is a relatively small-bodied species that is most abundant on offshore grounds and forms a relatively high proportion of skate landings in those areas where it is abundant. The catch rates below refer to all individuals (not just mature fish) and are typically nominal CPUE trends. Observed increases or declines tend to be of a moderate magnitude, but signals are inconsistent across surveys. The highest catch rates of this species are found off the east coast of Scotland and around Orkney and Shetland. It is abundant in the northern North Sea, off northwest Scotland, the Irish Sea, the Celtic Seas, and is also one of the dominant skates around the Iberian Peninsula (ICES 2006). It is only rarely observed in the inner parts of the Bristol Channel and in the eastern English Channel and southern North Sea. Preliminary stock assessments were made for the Celtic Sea stock during the Development of Elasmobranch DELASS project (Heessen 2003), though the results were inconclusive.Mean abundance of this skate in the North Sea ecoregion appears to have increased from the late seventies to early eighties, followed by a sharp decline (Daan et al. 2005), and then by stabilisation in recent years at very low levels (ICES 2012). Fishery-independent mean catch per unit effort (CPUE) of the species for quarter one of the international bottom trawl survey in the North Sea was ~0.5 individuals per hour from 2010 to 2011, falling above the mean for the period 2005 to 2009, having increased by ~60% in three to four years from a low of ~0.2 individuals per hour in 2007 (ICES 2012). The stock is concentrated in the northern and central parts of the North Sea. For quarter three of the survey, mean CPUE for 2010 and 2011 was also higher than the mean for the period 2005 to 2009, having increased by ~53% in three to four years from a low of approximately 0.38 individuals per hour in 2007, to approximately 0.8 individuals per hour in 2011 (ICES 2012). The exploitation level of the North Sea stock is still unknown. It should be noted that survey catch rates are based on all individuals, rather than adults alone.The stock structure of this skate in the Celtic Seas and waters west of Britain is insufficiently known, which makes the interpretation of catch rates in the various surveys more problematic (ICES 2012). As an offshore species that is also present in the Bay of Biscay (VIII) and northern North Sea (IVa), it is possible that the stock or stocks extend out of the Celtic Seas ecoregion. The French EVHOE survey of this ecoregion suggested peaks in relative abundance in 2001, 2002, 2007-2008 with the lowest catch in 2000 (ICES 2012). The Spanish survey on the Porcupine Bank indicated recent decreases in catch rates over a four year period both in terms of biomass (~50%) and abundance (~81%) (from ~0.5 kilograms or 0.75 individuals per haul in 2007 to ~0.25 kilograms or 0.25 individuals in 2011), although catch rates in the last few years are comparable to those observed at the start of the time-series (ICES 2012). Earlier analyses of Scottish survey data from waters west of Scotland suggested stable or increasing catch trends (ICES 2012), although more recent data were not available. The English and Welsh beam trawl survey in the Irish Sea indicated a decline in mean CPUE of ~42% over 19 years from ~2.4 individuals per hour in 1993 to ~1.4 in 2011, with the mean catch rates from 2010 and 2011 lower than those from 2005 to 2009 (ICES 2012). From the Irish Groundfish Survey of this area, trends in abundance are not apparent, with variable annual catches and a mean CPUE of approximately one individual per hour, falling within the lower margin of the mean CPUE for the period 2005 to 2009 (ICES 2012). The biomass indices reported by Spanish fishery-independent trawl surveys of Spanish Atlantic waters show annual variation of ~60% between 0.2 and 0.5 kilograms per haul, with an overall increase in catch rates (ICES 2012). Fishery-independent data for Portuguese waters are too limited to gauge longer-term trends.The landings per unit effort (LPUE) of this skate from the Bay of Biscay between 2002 and 2011 show constant values between 50 and 68 kilograms per day, excluding the lowest values of approximately 34 tonnes overall for 2004 and 48 tonnes in 2010  (ICES 2012). The relationship between Cuckoo Skate populations in the Celtic Seas and Bay of Biscay region is unknown.Mediterranean SeaThis skate appears to have always been relatively uncommon in the Mediterranean Sea; it was rarely caught in the International Trawl Survey in the Mediterranean (MEDITS) from 1994-1999. The MEDITS covers the northern Mediterranean coast almost continuously from west Morocco and Spain in the west, to the Aegean Sea in the east (Baino et al. 2001). Six trawl surveys are carried out each year in the coastal areas of four arbitrary geographically defined areas: western (Morocco, Spain, France), western central (Tyrrhenian, Corsican, Sardinia and Sicily coasts), eastern central (Adriatic, Ionian and Albanian coasts) and eastern (Aegean Sea). A total of 6,336 tows were performed between 1994 and 1999 at depths ranging from 10-800 m. This species was recorded in only 42 of 6,336 tows during this survey (frequency of occurrence of 1%) and was more frequently captured in the eastern area (Baino et al. 2001). A time series of comparative trawl surveys in the Gulf of Lions indicate that this skate was historically present in both shelf and slope trawl surveys in 1957-1960 and in 1980-1984 (150-800 m), but was not present on the shelf or slope in comparable surveys in 1992-1995 (Aldebert 1997), indicating local extinction from this area.This species does not appear to have been captured in historical and recent trawl surveys of the Adriatic Sea (Jukic-Peladic 2001). Massuti and Moranta (2003) reported it in relatively recent trawl surveys off the Balearic Islands. Little is known of its current distribution and abundance along northwest African coastlines, except that it now appears to be uncommon in Tunisian waters.The overall population trend of the species in European waters is unknown.

habitat:
The species is found on the continental shelf and slope at depths of 20-500 m, and more commonly at about 200 m in the Mediterranean Sea (Serena 2005). It is typically an offshore species, occurring further offshore than, for example, Spotted Skate (Raja montagui) and Thornback Skate (Raja clavata). It is abundant on coarse sand and gravel substrates in the Irish Sea and western English Channel. The size at maturity is estimated at 55 cm total length (TL) for both males and females (Walker 1999) with a maximum size of about 72 cm TL (Stehmann and Bürkel 1984, Ellis et al. 2005). In the Mediterranean Sea, the maximum size recorded is about 70 cm TL and size at first maturity is 60 cm TL in females (Serena 2005). Age at maturity for females and males is estimated at 7.4 and 6.8 years, respectively, in the North Sea (Walker 1999), and age at 50% maturity is just over four years in the Irish Sea (Gallagher et al. 2005). Around the British Isles, males and females first mature at 48 and 45 cm TL, respectively (McCully et al. 2012). Additionally, length at 50% maturity (L­­50) is estimated as 56.3 cm (males) and 59.4 cm (females). There is a significant difference in the L­­50 for both sexes between the North Sea and Celtic Seas ecoregions, with females and males in the North Sea 6.2 to 6.5 cm smaller at this stage than in the Celtic Seas. The estimated L­­50 in Portuguese waters is 56.5 and 56 cm TL for females and males, respectively (Maia et al. 2012). Longevity is reported at 12 years (Du Buit 1976b), which in conjunction with an age at 50% maturity of four years would indicate a generation time of eight years for individuals in the Irish Sea. In Portuguese waters, actively spawning females and males can be found throughout the year, though the percentage of actively spawning individuals is higher between January and May (Maia et al. 2012). The maximum potential fecundity is estimated between 60 and 63 mature follicles for spawning-capable and actively spawning females, respectively. Batch fecundity was estimated as seven follicles per batch, with nine reproductive episodes per female. Other studies have indicated that females produce about 90 eggs per year after an eight month gestation period (Clark 1922, Du Buit 1976a, Bauchot 1987).

threats:
The species is taken as bycatch in mixed demersal fisheries through much of its range and usually retained. Due to occurring further offshore than other skates, this species is less important to recreational fisheries. Increasing fuel prices are thought to have resulted in some fisheries operating closer to port, which may benefit offshore skates.Northeast AtlanticSkates are an important component of the demersal fisheries of northwest Europe; when caught, this species is landed and sold (Holden 1977, Dulvy et al. 2000). Off the Bay of Biscay it is mainly landed by polyvalent trawlers and longliners operating further offshore (ICES 2013). It may be an important component in mixed demersal fisheries where abundant, and is landed as a bycatch in trawl fisheries throughout its Atlantic range, though smaller individuals tend to be discarded (Silva et al. 2012). This skate is one of the more frequent species landed by the commercial fisheries operating in the Celtic Sea and Iberian waters. Craven et al. (2013) found it to be the dominant bycatch species of scallop dredge fisheries in the northern Irish Sea around the Isle of Man, constituting around 27% of total bycatch.Mediterranean SeaThe situation in the Mediterranean Sea may be similar to that in the Northeast Atlantic: this species may be part of the bycatch of multispecies trawl fisheries typical in the shelf seas of the Mediterranean basin. Demersal trawl effort has increased both numerically and in technological terms in the shelf and slope areas of the Mediterranean Sea over the last 50 years. The continental shelf and upper slope are highly exploited, with intensive commercial trawling occurring at depths ranging from 50-800 m (Colloca et al. 2003, Massuti and Moranta 2003). Although only adult individuals may be landed for consumption, most size classes are likely to be taken in fishing nets as the legal mesh size used in much of the Mediterranean Sea is approximately 20 mm. The relatively small size of this skate suggests that its life history and demography may allow some capacity to withstand moderate fishing pressure (Dulvy et al. 2000, Stevens et al. 2000).

conservationAction:
Though there are no species-specific management measures in place, there is a Total Allowable Catch (TAC) for skates and rays in the Northeast Atlantic, and this species may benefit from more generic management measures for demersal fisheries (e.g., mesh size regulations and effort reduction). More information on stock status is required, and the status of stocks in those areas where this species is exploited most (e.g., Celtic Seas) need to be better assessed.In 1999, the European Union (EU) introduced a TAC for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea and North Sea (International Council for the Exploration of the Sea [ICES] Division IIa and Subarea IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999-2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES Subareas VI-IX) and have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 t (regulations are available online at http://faolex.fao.org).Since 2008, the European Commission has obliged member states to provide species-specific landings data for the major North Sea species, including Cuckoo Skate, in order to improve understanding of skate stocks in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009), and has been ongoing since 2008 (CEC 2013). EC Council Regulation 43/2012 that established a TAC of 4,222 t in 2012 for skates (all species in the family Rajidae) in ICES Subareas VIII and IX (Bay of Biscay and Iberian waters) also indicated that catches of Cuckoo Skate and Thornback Skate should be reported separately (ICES 2013).Further research should be conducted on the population size and trend of the species.

useAndTrade:
In the Northeast Atlantic, when caught, this species is landed and sold (Holden 1977, Dulvy et al. 2000). 

redListContributors:
Fordham, S., Ungaro, N., Serena, F., Tinti, F., Bertozzi, M., Pasolini, P., Mancusi, C. & Notarbartolo di Sciara, G.


redListCategoryRationale:
Krefft’s Skate (Malacoraja kreffti) is a relatively small deepwater skate. This demersal species occurs at depths of 1,0001,500 m, placing it outside of the current range of deepwater fisheries. Commercial fisheries do not target this species, but it is occasionally caught as bycatch. Krefft’s Skate is assessed as Least Concern in European waters based on its deep range and limited interaction with fisheries. If fisheries expand into deeper water within this species’ range, this assessment may need to be re-visited. Further research should be conducted on the life history of the species.

range:
This species occurs at the Rockall Trough west of Scotland and Ireland (Stehmann 1977, 1993), southwest of Iceland (Jónsson and Pálsson 2006) and the Porcupine Seabight (Dransfeld et al. 2007, Johnston et al. 2010). It is suspected to have a wider range than currently reported, extending south to the Bay of Biscay and the Mid-Atlantic Ridge. Its depth range is 1,000-1,500 m.

population:
No data on population trends or structure are available. This species is suspected to be very rare, but given its limited interaction with fisheries, it is suspected to be stable.

habitat:
This benthic skate occurs on deep inner and outer slopes and submarine rises at depths of 1,0001,500 m (Stehmann 1977, 1993). It is only known from a small number of individuals so limited information is available on its life history and reproduction. A female measuring 48.8 cm total length (TL) was probably mature (Stehmann 1993) and the smallest mature male measured 51.5 cm TL (Stehmann 1977). The largest recorded specimen measured 57 cm TL (Stehmann 1993), although the species probably grows to around 70 cm TL (Stehmann and Bürkel 1984). Like other skates, this is an egg-laying species (Ebert and Stehmann 2013).

threats:
This species is occasionally taken as bycatch of deepwater fisheries, but only seasonally and locally. It is thought to occur largely outside the range of current deepwater fisheries as all specimens have been taken at depths greater than 1,000 m. Deepwater trawling may become a threat if operations expand deeper into this species range, however there is no indication of fisheries expansion at this time. 

conservationAction:
Currently, there are no species-specific management or conservation measures in place, although catches of skates and rays are restricted in European waters. In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 825% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (19992014), the TAC was higher than reported landings and therefore not effectively constraining catches.Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VIIX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).In the future, bycatch and the extent of deepwater fisheries should be monitored. Further research should be conducted on the life history of the species.

redListContributors:
Kyne, P.M., Gerber, L., Sherrill-Mix, S. & Walls, R.


redListCategoryRationale:
European regional assessment: Least Concern Roughskin Skate (Malacoraja spinacidermis) is a little-known medium-sized (up to 71 cm) skate that occurs at depths of 4751,570 m, but usually greater than 1,000 m. It appears widespread, but there are few records, particularly in the Northeast Atlantic. This species is not targeted by fisheries, but it is occasionally taken as bycatch in deepwater fisheries. It may be more common in deeper waters that are not presently exploited by commercial trawlers. Given that most of its range is considered to be outside the reach of deepwater fisheries and it is only occasionally caught as bycatch, Roughskin Skate is assessed as Least Concern in the European region. Expansion of trawling operations to deeper waters could pose a threat in future and should be monitored. Collecting catch data and life history information should be a priority.

range:
In the Northeast Atlantic, this species is known to occur southwest off Iceland, the Rockall Trough, the Faeroe Ridge (Jónsson and Pálsson 2006), south of Greenland (Nakaya 1995) and across the Davis Strait to the Grand Banks. The depth range is 4751,570 m, but usually greater than 1,000 m, and adults may live deeper than 1,500 m, down to the abyssal plains. The species is also found off Canada, Namibia and South Africa.

population:
This widespread species appears to be uncommon. No information on population trends or structure is currently available, but the population is inferred to be stable based on its limited interaction with fisheries.

habitat:
This demersal deepwater skate occurs at depths of 4751,570 m, but usually greater than 1,000 m. Adults may live deeper than 1,500 m, down to the abyssal plains (Ebert and Stehmann 2013).Very little is known about this egg-laying species. It has small egg cases, but hatching size is uncertain (Ebert et al.2008). Most biological information is known from records off South Africa; the smallest free-swimming specimen ever recorded is 12.7 cm length, the maximum recorded body size is 70.5 cm TL, and the estimated length at maturity for males and females is 48 cm and 45.4 cm TL, respectively (Ebert et al.2008).

threats:
This species is not targeted by commercial fisheries, but it its taken as bycatch in deepwater fisheries. Given that most records are from greater than 800 m depth, this skate likely occurs at depths greater than those that are normally surveyed or fished. Fisheries bycatch may pose a greater threat in the future if deepwater trawling expands, but this is unlikely for the moment.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 825% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (19992014), the TAC was higher than reported landings and therefore not effectively constraining catches.Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VIIX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).The harvest trends of the species should be monitored.

useAndTrade:
This species is not exploited nor traded commercially.


taxonomicNotes:
Originally described in the genus Breviraja.

redListCategoryRationale:
Blue Pygmy Skate (Neoraja caerulea) is a poorly known, small (up to 32 cm total length), deepwater skate that occurs at depths of 600–1,260 m. It is endemic to the Northeast Atlantic and appears to be relatively rare. It was only known from the type series until further records of this species were obtained with the development of deepwater fisheries on the continental slopes and scientific exploration cruises in the Northeast Atlantic. This species is occasionally taken as the bycatch of deepwater trawl fisheries, but most of its depth range lies beyond the reach of the main deepwater fisheries. Given its limited interaction with fisheries and deep range, it can be inferred that the risk of exploitation is low. For this reason, Blue Pygmy Skate is assessed as Least Concern.

range:
In the Northeast Atlantic, this skate is endemic to the continental slopes and adjacent banks along the Rockall Trough, west of Scotland and Ireland, and in the Bay of Biscay (Ebert and Stehmann 2013). Rodriguez-Cabello et al. (2013) reported a southward range expansion into deeper waters of the southern Bay of Biscay, off Galicia. Its depth range is 600–1,260 m.

population:
No information on population trends or structure is available, although this species appears to be rare where it occurs. The population is inferred to be stable based on its limited interaction with fisheries.

habitat:
This species occurs on continental slopes at depths of 600–1,260 m and it prefers mud and sand substrates (Stehmann 1976, Stehmann et al. 2008). The hydrographic conditions where it has been found suggest that it prefers temperatures that are > 6°C and salinities that are > 35 practical salinity units. If this is the case, the maximum depth of this species is c. 1,300 m (Stehmann 1976, Stehmann and Bürkel 1984, Stehmann et al. 2008).Like other skates, this is likely an egg-laying species. Size at maturity for males is 20−25 cm total length (TL) and unknown for females. A 19.6 cm TL male found was immature while a 27 cm TL male was mature (Ebert and Stehmann 2013). The maximum reported size for this species is a 32 cm TL male (Stehmann and Bürkel 1984, Quéro et al. 2003).

threats:
This skate is not targeted by commercial fisheries, but it is occasionally taken as bycatch of deepwater bottom trawl fisheries operating in the Northeast Atlantic. It mainly occurs at depths beyond the reach of deepwater fisheries. If fisheries expand into deeper parts of its range, fishing pressure could pose a greater threat, but currently there is no indication that this could happen.

conservationAction:
No species-specific management or conservation measures are currently in place. Monitoring of catches and further surveys are required to define this species’ full range, abundance and interaction with fisheries.


redListCategoryRationale:
Iberian Pygmy Skate (Neoraja iberica) is a recently described species, known only from a few specimens caught off the northern coast of Spain and southern coasts of Spain and Portugal. It is found on the upper continental slope at depths of 270−784 m. It is rarely caught even though commercial fishing for groundfish and crustaceans have been operating within its range for a long time. No catch data are available to evaluate historical population trends and no information is available on the extent of bycatch or post-discard mortality. This species is assessed as Least Concern in the European region because there is no evidence of population decline in European waters, and most of its range is beyond the reach of most commercial fisheries.

range:
In the Northeast Atlantic, this species is only known from a few specimens caught off northern Spain and southern Spain and Portugal, within the Bay of Cádiz (Stehmann et al. 2008, Rodriguez-Cabello et al. 2013, Ebert and Stehmann 2013). The occurrence of this species in intermediate regions is unknown, though its natural range is suspected to be continuous around the Iberian Peninsula. The depth range is 270-670 m.

population:
This species is somewhat rare. No data on population size and trend are available.

habitat:
The species occurs on the upper slope at depths of 270-670 m, on fine sand and occasionally muddy sand substrates (Stehmann et al. 2008). It attains a maximum size of 32.7 cm total length (TL) (Stehmann et al. 2008). Reproduction is presumably oviparous, like other skates. Size at birth is unknown, but the smallest neonate measured is 5.5 cm TL, and so it is probably close to this (Stehmann et al. 2008).

threats:
This species is taken as bycatch in demersal crustacean trawl fisheries and discarded because it is considered too small to be commercially valuable (Ebert and Stehmann 2013). Although it is not taken regularly, it occurs in an area that has been commercially fished for groundfish and crustaceans for a long period (Borges et al. 2001, Monteiro et al. 2001, Stehmann et al. 2008). Fisheries targeting Rose Shrimp (Parapenaeus longirostris) and Norway Lobster (Nephrops norvegicus) operate off the south coast of Portugal at depths of 200−700 m, which overlaps with the known depth range of this species (ICES 2006). No data are currently available on the capture of this species and nothing is known about post-discard survival rates, so it should be studied in the future.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian and North Seas (International Council for the Exploration of the Sea [ICES] Division IIa and Subarea IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches (ICES 2007). Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES Subareas VI−IX) and have also been gradually reduced since then.Population and harvest trends need to be monitored through research surveys or the collection of species-specific catch data by onboard observers.

redListAssessors:
Farrell, E., Stehmann, M.F.W. & Valenti, S.V.


redListCategoryRationale:
Starry Skate (Raja asterias) is distributed primarily in the Mediterranean Sea. It is caught as bycatch by bottom trawl, trammel net, and gill net fisheries especially in the Italian, French and Spanish seas. This skate is relatively fast growing with an early age of maturity (the three generation span is ~ 19 years), high fecundity and a short life span, which indicates that it is relatively productive and resilient to fishing pressure. There have also been steep declines in landings over a 25 year period (1969-1994) in the Gulf of Lions. It is suspected that these trends are likely to be representative throughout its range. Starry Skate is inferred to have undergone a decline of 20% throughout its distribution, and it is therefore assessed as Near Threatened as it is close to qualify as threatened under Criterion A2. Further information on its status in the southern Mediterranean Sea is needed.

range:
Starry Skate (Raja asterias) can probably be considered endemic in the Mediterranean Sea, but may also occur in the Atlantic, near the southern coast of Portugal (Serena 2005). It has been reported for the northern and southern areas of the Balearic Islands of the western Mediterranean Sea (Massutì and Moranta 2003), in the Tyrrhenian Sea of the northern Mediterranean (Romanelli et al. 2007), as well as along the Tunisian coasts (Capapé 1977), and in the central Tyrrhenian Sea (Minervini et al. 1985).

population:
Genetic analysis suggests at least two distinct clusters: Western and Eastern Mediterranean basin, and Sicilian coast and Algeria, and possibly other countries in North Africa (Gerotto 2013). This species was captured in both the GRUND (Italian waters) and MEDITS (northern Mediterranean basin) trawl surveys (Relini 1998, Bertrand et al. 2000), which began in 1985 and 1994 respectively. In the south Ligurian and north Tyrrhenian Sea it was captured over muddy bottoms, in restricted coastal areas from nine to 190 m depth, but mainly concentrated at 100 to 150 m depth. From 1999 to 2004 the difference between the Biomass Index and Density Index decreased, which may indicate a change in the population structure with a predominance of smaller specimens (Serena et al. 2005). The species has a higher relative abundance on the Italian and Corsican continental shelves (Baino and Serena 2000, Serena et al. 2005). Nursery areas are located very close to the coast at two to 15 m depth (Abella and Serena 2005).Landings of Starry Skate in the southwest North Sea and eastern English Channel, as reported by France, are likely the result of misidentification or incorrect use of species codes (ICES 2012).Catches in the Aegean Sea MEDITS bottom trawl surveys, from 1998 to 2008, ranged from 24 specimens (9.85kg) in 1998, to nine (2.01kg) in 2003, to 34 (13.91kg) in 2008. Inter-annual variability was high, but there was no overall trend for the time series (Tserpes et al. 2013).There have been estimated declines in the MEDITS program in the Adriatic Sea (Ferretti et al. 2013), and landings declined over 25 years (1969-1994) in the Gulf of Lions despite no apparent decrease in fishing effort, and in this region the species disappeared entirely from catches in waters >150 m between 1957 and 1995. In waters <150 m deep, it declined by approximately 20%. The same negative trend is reported for the Spanish Mediterranean area. It is suspected that these trends are likely to be representative throughout the species’ range, and thus the species is inferred to have undergone a decline of 20% throughout its distribution during the three-generation period (19 years).

habitat:
Starry Skates are found predominantly on the Italian and Corsica continental shelves between shallow waters and 150 m depth (Baino and Serena 2000). In the eastern Ionian Sea, the species is found down to depths of 343 m (Mytilineou et al. 2005), although this is probably due to misidentifications. The species prefers muddy and sandy bottoms (Vannucci 2005). Maximum size is estimated at 72 cm total length (TL) for males and of 76 cm TL for females (Bono et al. 2005, Serena and Abella 1999). Barone et al. (2006) and Serena et al. (2005) estimate length at maturity at 51.7 cm TL for males and 56.1 cm TL for females, and Serena and Abella (1999) and Bauchot (1987) reported length at maturity at 45 to 54 cm TL for males and 60 cm TL for females. Age at maturity is reported at three to four years for both males and females (Serena and Abella 1999, Bono et al. 2005). The species is egg laying, with 34 to 112 egg cases laid depending on individual size, and egg cases can reach 45 mm in length and 30 mm width (Bauchot 1987). Juveniles are about 8 cm TL when they emerge from the egg cases in January. The sex ratio is about 1:1 (Minervini et al. 1985, Abella et al. 1997). Juveniles move quickly into shallow waters from 5-7 m depth soon after birth and then move into deeper waters progressively as they grow (Abella and Serena 2002, Catalano et al. 2003).Recent preliminary tagging experiments (Catalano et al. 2003) suggest a faster growth rate than described in previous literature (Serena and Abella 1999). As this species reaches maturity relatively early (~3 years) and has a short lifespan (~10 years) it is considered to be relatively productive, even though it is only moderately fecund. In the Central Tyrrhenian Sea, length at 50% maturity values estimated by Romanelli et al. (2007) were 56.5cm TL and 50.5cm TL for females and males, respectively. In the south Ligurian Sea, males mature by 45 cm TL and females may mature by 53 cm TL (Barone et al. 2007). Total length at 50% maturity was estimated to be 51.7 cm and 56.1 cm TL for males and females respectively. In the Catalan Sea, the size at first maturity for females was assessed to be around 48.1 cm TL, while males showed a maturing phase from 45 to 51 cm TL (Coll et al. 2013). These estimates are lower than the ones reported in the Gulf of Tunisia (Capapé 1977). The annual rate of population increase is 0.247 year-1, and estimated generation time is 4.36 years; the time taken to double the population is 2.81 years (Abella et al. 2011). The estimated generation length is around 6 years.

threats:
The species is mainly caught by beam trawls, bottom trawls, trammel, and gill nets. Near the Corsican coast in particular, fishing pressure is low because only a few Corsican trawlers, as well as a few Italian vessels, operate in this area (Abella and Serena 2002). A reduced number of trawlers belonging to the La Spezia fleet operate on the same grounds northwards to Viareggio harbour (the most important fishing port of the north Tyrrhenian- south Ligurian Sea). The Livorno fleet operating in the same area is also relatively small. Trawlers concentrate their effort mainly on the grounds at depths between 100 and 400 m and therefore there is a little overlap with areas in which the Viareggio fleet operate. Off Tuscany (Ligurian Sea), it is mainly landed as bycatch of beam trawlers, targeting common sole and turbots, however very few of these operate in this area (Abella and Serena 2002). Most small individuals caught near shore with trammel and gill nets by these artisanal fisheries are landed. However the ban on trawling within three miles of the coast in this area of the Mediterranean Sea affords protection for this species' shallow nursery areas. Moreover, a general reduction in fishing effort on the grounds traditionally exploited by the Viareggio fleet occurred during the last 15 years because the number of vessels in operation reduced from 107 in 1985, to 78 in 2000 (Abella and Serena 2002). Little information is available on the probability of survival of discarded juveniles. Preliminary experiments performed with individuals caught and successively put into marine water pools have demonstrated high rates of survival for released individuals caught with bottom trawl nets (Catalano et al. 2003). Although this skate is one of the more exploited species in the Ligurian Sea, it is apparently relatively resilient to fishing pressure as a result of its life history characteristics. It is relatively productive due to its early age of first maturity (about three years) and relatively short lifespan (about 10 years), even if it is only moderately fecund (Abella and Serena 2002).Data available for Starry Skate in the North Sea and eastern English Channel are thought to be unreliable owing to confusion between this species and Blonde Skate (R. brachyura) (ICES 2012). Fishing mortality calculated from the model in 1978 was assessed to be 74% of total mortality, much higher than the mortality of this group due to predation (Coll et al. 2013).In the northwest Mediterranean Sea, bottom-trawling operations capture large amounts of juvenile fish due to their low selectivity (Sardà et al. 2004) and Starry Skate is sensitive to the type of non-selective commercial trawling operating throughout the Mediterranean Sea from hatchling to adult sizes (Coll et al. 2013). Results from Coll et al. (2013) confirmed that the species has been and still is highly affected by fishing in the Catalan Sea, particularly trawling, and is very sensitive to increasing fishing effects. Under the current situation and under situations of increasing fishing effort in the future, this skate may disappear from the Catalan Sea, as it has already happened with other rays and skates in highly exploited areas of the North Atlantic (Brander 1981; Casey and Myers 1998, Dulvy et al. 2000). Fishing effects in the Mediterranean Sea are high, and it is likely populations are at low levels. Continental shelves and coastal areas of the whole Mediterranean Sea are currently subjected to a high fishing pressure from a highly diversified fishing fleet (Coll et al. 2010), therefore posing high threat to populations of Mediterranean endemic rays and skates (Aldebert 1997, Ferretti et al. 2010). Starry Skate primarily occupies these areas, and frequently occurs at smaller depths than the depth benchmark of 63 metres for White Skate (Rostroraja alba), which is now locally extinct in parts of the Atlantic and Mediterranean Sea owing to overfishing (Dulvy and Reynolds 2002). Additionally, Starry Skate has a smaller latitudinal range than White Skate and a restricted geographic range, thus making it perceivably more sensitive to fishing (Notarbartolo Di Sciara 1998; Dulvy and Reynolds 2002). Finally, strong declines have been documented in regions where immediate deeper refuges are not available, such as in the Gulf of Lions and the Adriatic Sea (Aldebert 1997, Jukić-Peladić et al. 2001). A recent regional analysis of human effects in the Mediterranean Sea illustrated that fishing intensity is currently high in most coastal and continental shelf systems where this skate is distributed (Coll et al. 2010), therefore fishing effects may be higher than previously evaluated. However, Coll et al. (2013) showed that Starry Skate may respond well under decreasing trawl fishing effort and could substantially recover in the Mediterranean Sea if this were to occur.

conservationAction:
The development and implementation of management plans (national and/or regional e.g., under the FAO International Plan of Action for the Conservation and Management of Sharks: IPOA-Sharks) are required to facilitate the conservation and sustainable management of all chondrichthyan species in the region. The Portuguese Administration adopted a national legislation in October 2011 (Portaria no 315/2011) that prohibits, along the whole continental Portuguese Exclusive Economic Zone, during the whole month of May, the catch, the maintenance on board and the landing of any skate species belonging to the genera Raja or Leucoraja (ICES 2012). Additionally, each fishing trip is allowed a maximum of 5% bycatch, in weight, of those species to be maintained on board or landed.Further research and monitoring of the population where it is fished is required to prevent declines in the future.

useAndTrade:
There is no information available on the use and trade of this species.

redListAssessors:
Serena, F., Abella, A., Walls, R. & Dulvy, N.


taxonomicNotes:
This species has been confused with Raja montagui and Raja polystigma in the Mediterranean Sea (Bertozzi et al. 2003).

redListCategoryRationale:
European regional assessment: Near Threatened (NT) The Blonde Ray (Raja brachyura) is a relatively large-bodied skate, endemic to the northeast Atlantic Ocean and the western Mediterranean Sea. It occurs on soft substrates to depths of about 150 m in the northeast Atlantic and mainly from 10-300 m depth in the Mediterranean Sea. It is targeted in areas where it is locally abundant and taken as bycatch in mixed demersal fisheries using trawl, gill nets and longlines elsewhere in its range. It is apparently rare in the Mediterranean Sea, captured in only 21 of 6,336 tows in Mediterranean-wide trawl surveys conducted between 1994-1999 (at depths of 10-800 m). It is not certain whether the Blonde Ray has always been rare there; no data are currently available on historical abundance or trends for this region and there is no evidence to suggest it was ever common. The lack of data on this apparently rare species prevents an assessment beyond Data Deficient in the Mediterranean Sea at present, but given that demersal fishing pressure is relatively intense throughout large areas of its range there an assessment of catches is a priority. This species is more common in the Northeast Atlantic Ocean where it is taken as bycatch and is also targeted where sufficiently abundant. No formal stock assessments have been undertaken for this species. Although it is locally abundant in some areas, survey data indicate that declines have occurred. Medium sized skates showed marked declines in relative abundance, especially the Blonde Ray, in comparable research trawl surveys conducted in three localities around the British Isles in 1901-1907 and 1989-1997. Furthermore, the percentage composition of the Blonde Ray decreased by close to 30% between the two survey periods. Demersal fishing pressure is still high throughout large areas of the Northeast Atlantic and declines are inferred elsewhere, where specific data are not available. This species probably has limiting life-history characteristics, like other relatively large skates, making it vulnerable to depletion. Given observed and inferred declines, continued high levels of exploitation and this species' rarity in the Mediterranean Sea, it just fails to meet the criteria for Vulnerable A2bd globally and is assessed as Near Threatened. Improved monitoring of population trends and further assessment of the Atlantic and Mediterranean subpopulations are a priority.

range:
This species is widespread in the northeast and eastern central Atlantic Ocean. It occurs in shelf waters from Madeira and Morocco in the south to the Shetland Isles in the north, including the Irish Sea, the English Channel and the southwestern North Sea (Stehmann and Bürkel 1984, Ellis et al. 2005a, ICES 2006). In the Mediterranean Sea, this skate is known to occur off Spain, France, western Italy, Tunisia, Algeria and Morocco (Bauchot 1987, Bertrand et al. 2000, Baino et al. 2001, Bertozzi et al. 2003). There is one questionable record from the northern Aegean Sea (Serena 2005).

population:
Although Blonde Skate (Raja brachyura) has a relatively broad geographic range, this species is most abundant in the Atlantic Ocean from from the British Isles to Portugal. Areas where it is locally abundant include the inshore and shelf waters (down to about 150 m) in the English Channel and Irish Sea, Bristol Channel and St George’s Channel (Fahy 1989, 1990, 1991; Ellis et al. 2005a). It is less abundant in the more offshore parts of the North Sea and Celtic Sea (Ellis et al. 2005a). Hence, this species may have a fragmented population, possibly due to the discontinuous nature of its favoured habitat (e.g., sand banks). Occurrence throughout the North Sea is patchy as Blonde Skate is at the edge of its geographic range here (ICES 2012). As a result, catches are low and highly variable, with a slight overall increasing trend for the time series. While the sporadic catches and patchy distribution could be interpreted as natural rarity, these patterns could also be symptomatic of depletion, as can be inferred from Piet et al. (2009); this study suggests that the fishing mortality rate of the species in the southern North Sea, particularly due to beam trawlers, is the highest faced by any skate. This species may have declined during the 20th century (Rogers and Ellis 2000) based on a comparison of standardised catch rates of demersal fish from research surveys in three areas around the British Isles (northwestern Irish Sea, Devon, and southern North Sea) from 1901 to 1907 with survey catches in the same areas from 1989 to 1997. In this analysis, skates of intermediate body size showed marked declines in relative abundance, especially Blonde Skate. Furthermore, the percentage composition of the Blonde Skate decreased by nearly 30% between the two survey periods. Catch rates in beam trawl surveys in the English Channel and Irish Sea appear steady at a low level in recent times (Ellis et al. 2005b), and there is no consistent trend in the North Sea (ICES 2006). However, these catch rates refer to all individuals and not just mature fish. Blonde Skate is locally abundant off southeast Ireland and the Bristol Channel, though its range throughout the Celtic Sea is patchy (Ellis et al. 2011). Mean catch rates in these areas are low and variable, but with an overall increasing trend in fisheries surveys despite the survey gear having low selectivity for large mature individuals (ICES 2012, 2013). Patchy data from Dutch beam trawl landings from the North Sea alone showed a 72% increase from 17,700 individuals in 2000 to 63,500 individuals in 2007, followed by a 91% decrease to 5,800 individuals in 2008, coinciding with a more restrictive Total Allowable Catch (TAC; ICES 2012). Species misidentification probably affects species-specific landings data in this instance. Blonde Skate is probably frequently mistaken for Spotted Skate (Raja montagui) in European nations where these species co-exist. Historically, Blonde Skate was amongst the most frequently caught skate species in the Bay of Biscay and Iberian Waters (ICES 2012). The level of exploitation of the species is moderate in these waters despite its low estimated abundance in this region. The total landings in these waters was 386 tonnes in 2012, principally comprising Portuguese landings (379 tonnes) in Iberian waters, with remaining landings made by France from the Bay of Biscay (ICES 2013). ICES (2012) reported a slight increasing trend in landings per unit effort (LPUE) and catch per unit effort (CPUE) of Blonde Skate between 2009 and 2011 in Portuguese waters. The increase in LPUE since 2008, along with the decrease in landings, indicates that the fishing mortality rate has decreased (ICES 2012). There is no evidence for reductions in the area of occurrence, despite an overall low frequency of occurrence. The state of the population in Spanish and Portuguese waters is therefore regarded as increasing. The Blonde Skate is relatively rare in the Mediterranean Sea, but it is unclear if it has always been rare. Recent population trends cannot be inferred for this species in the Mediterranean Sea because insufficient data are available, although a long term decline is suspected (MiPAAF 2014). This species was recorded in a total of 21 of 6,336 tows performed at depths of 10−800 m in the International Bottom Trawl Survey in the Mediterranean (MEDITS) programme between 1994 and 1999 (Baino et al. 2001). This survey covers the northern Mediterranean coast almost continuously from west Morocco and Spain in the west to the Aegean Sea and Cyprus Island in the east. It appears to be relatively rare in Italian Seas, with a low frequency of occurrence in Italian scientific trawl surveys Gruppo Nazionale Risorse Demersali (GRUND), MEDITS trawl surveys, and other surveys in this area (Follesa et al. 2003, Ragonese et al. 2003, Spedicato et al. 2003, Serena et al. 2005). Blonde Skate does not appear to have been captured in either historical or recent comparative trawl surveys of the Adriatic Sea or the Gulf of Lions (Aldebert 1997, Jukic-Peladic et al. 2001). Little is known of this species’ current range and abundance along northwest African coastlines, however it appears to be uncommon off Tunisia (Bradaï 2000).

habitat:
This species is most common on sandy sediments in waters down to about 150 m deep (Ellis et al. 2005a) in the Northeast Atlantic, though may occur deeper in the southern parts of its range. In the Mediterranean Sea, it is mainly found at depths of 10−150 m, to around 300 m (Baino et al. 2001). Like other skates, this is an egg-laying species. It reproduces between February and August, and has a gestation period of almost seven months. Females produce about 30 egg cases per year (Stehmann and Bürkel 1984). In the English Channel waters off Jersey, sexual maturity is reached at a length of 82 and 93 cm total length (TL) in males and females, respectively (Ellis et al. 2011). Similarly, length at first maturity for females in Portuguese waters was reported as 92 cm TL (Figueiredo et al. 2007). Trawl survey catches from the North Sea, English Channel, Irish Sea, Bristol Channel, and Celtic Sea, reported lengths at first maturity of 55 and 60 cm TL and length at 50% maturity of 78.2 and 85.6 cm TL for males and females, respectively (McCully et al. 2012). The largest immature specimens caught during this study were a 91 cm TL male and a 93 cm TL female. This species reaches a maximum size of approximately 120 cm TL (Stehmann and Bürkel 1984) and commonly reaches 40−80 cm TL.  Age data are limited (Gallagher et al. 2005), with age at maturity and maximum age suspected to be approximately 5 and 15 years, respectively. This would indicate a 10 year generation time.

threats:
This skate is an important component of demersal fisheries operating in areas where it is locally abundant in the Northeast Atlantic, and frequently landed and sold (Dulvy et al. 2000, Holden 1973). It is also taken in recreational fisheries and as bycatch of mixed demersal fisheries elsewhere in its Northeast Atlantic range. In the western English Channel, it was one of the main species retained and landed by all commercial fleets in 2010 and 2011 (Silva et al. 2012). Additionally, Blonde Skate comprised of 39−72% of Belgian and Irish landings from the Irish Sea and 32−39% of UK and French landings from the Bristol Channel during this time. This species is one of the most frequently landed skates by the commercial fleet on the Portuguese coast, accounting for 44% of the total individuals sampled in Peniche and 18% in Matosinhos (Machado et al. 2004). In the Mediterranean Sea, this skate is taken as bycatch of the semi-industrial (Spain) and artisanal (Morocco and Greece) fisheries using bottom trawls, gill nets and long lines (Bauchot 1987). Demersal trawl effort increased both numerically and in technological terms in the shelf and slope area of the Mediterranean Sea for a period of 50 years. For example, the Gulf of Lions area was historically exploited by small-scale trawl fisheries, comprising 27 small low powered boats (total nominal horsepower of 2,700 hp). Effort increased to a total nominal horsepower of 19,940 hp from 1974 to 1987. The continental shelf and upper slope of the Mediterranean Sea are highly exploited, with intensive commercial trawling occurring at depths of 50−800 m (Colloca et al. 2003, Massuti and Moranta 2003).

conservationAction:
There are no species-specific management or conservation measures currently in place. There are Total Allowable Catch (TAC) measures in place for all rays and skates combined. In 1999, the European Union (EU) introduced a TAC for skates and rays of 6,060 tonnes (t) for fisheries operating in EU waters of the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches, although this can be influenced by quota allocation. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).  To improve our understanding of skate populations in European waters, the European Commission obliged member states to provide species-specific landings data for the major North Sea species, including Blonde Skate, in 2008 (CEC 2008). In 2009, this obligation was extended to other ICES Divisions, including the Celtic Seas (CEC 2009), and has been ongoing (CEC 2013). Norway banned the discarding all skates caught in the Norwegian Economic Zone in 2009 (ICES 2012). Some of the regional Inshore Fisheries and Conservation Authorities bylaws enforce a minimum landing size of 40 cm disc width for skates and rays caught in the inshore waters of England, and off Wales. In future, this species may benefit from generic management measures for demersal fisheries such as mesh size regulations or effort reduction. Research is required on population numbers and trends, range, biology, ecology, habitat status and threats.

useAndTrade:
This skate is an important component of demersal fisheries operating in areas where it is locally abundant in the Northeast Atlantic, and frequently landed and sold and is also taken as bycatch in fisheries targeting other demersal species (STECF 2014). The fish is also taken in recreational fisheries elsewhere in its Northeast Atlantic range. In the Mediterranean Sea, this skate is taken as bycatch of the semi-industrial (Spain) and artisanal (Morocco and Greece) fisheries using bottom trawls, gill nets and long lines (Bauchot 1987).

redListAssessors:
McCully, S., Serena, F., Walls, R.H.L., Morey, G & Ellis, J.R.

redListContributors:
Dulvy, N.K., Notarbartolo di Sciara, G., Bertozzi, M., Ungaro, N., Tinti, F. & Mancusi, C.


redListCategoryRationale:
European regional assessment: Near Threatened (NT) Thornback Skate (Raja clavata) is widespread and one of the more abundant elasmobranchs in the inner continental shelf seas of Europe. In European waters, there are two distinct subpopulations. Within the Northeast Atlantic, the most consistent source of species-specific information is from scientific trawl surveys, which generally indicate either stable or increasing catch rates over the span of the most recent two generations. Historically, much steeper declines in catch rate and geographical extent were estimated in the English Channel, Irish Sea, and North Sea. Furthermore, the geographic range within the Northeast Atlantic has decreased on around 30% over the three-generation period (around 33 years). Moreover, the current status is reliant on on-going fisheries management of the skate complex. Within the Mediterranean Sea, the most consistent source of species-specific information is from scientific trawl surveys spanning the past two generations that indicate stable or slightly increasing catch rates in some areas. Earlier, longer survey time series in the Gulf of Lions (1969-1994) suggest longer-term declines in abundance. The species is therefore assessed as Near Threatened, as it is close to meet the thresholds for a threatened category under criterion A2. Ongoing monitoring and management of this skate is required in all areas. The status in areas with no or limited fisheries management may warrant a threatened listing in the future.

range:
Thornback Skate (Raja clavata) is widely distributed from Iceland and Norway to the North Sea (where it is now less abundant in the south-eastern fringe, Walker 1998), Atlantic shelf of western Europe, Mediterranean Sea, the western Black Sea, Madeira and the Azores. There are thought to be inherent differences between the Northeast Atlantic and the Mediterranean and Black Sea subpopulations (Chevolot et al. 2006, Naylor et al. 2012). Its depth range is 10-300 m.Northeast AtlanticThis species is probably the most significant ray for the commercial fisheries of the North Sea English Channel, Bristol Channel and Irish Sea (ICES 2013). A century ago, this skate occurred throughout much of the North Sea (ICES 2002). Nowadays it is concentrated in the southwest North Sea, from the Outer Thames Estuary to the Wash in East Anglia. It has largely disappeared from German waters in the southeast North Sea. Preliminary analyses of data from scientific trawl surveys indicated a large decrease in its range (ICES 2006), but further investigation of these data observed identification issues; some data were confounded with Starry Ray (Raja asterias), which is also named Thorny Skate in some areas. Subsequent analyses have confirmed that the area occupied by Thornback Skate is concentrated in the southern North Sea (Fock 2014). Now, the Greater Thames Estuary and The Wash are the only remaining parts of its North Sea range. It is however known to migrate from this area to the eastern English Channel, so the decline in range size might be less substantial (Hunter et al. 2005, 2006; Ellis et al. 2008). This skate is also relatively abundant in parts of the Irish Sea, especially Solway Firth, Liverpool Bay and Cardigan Bay. Highest concentrations across the Celtic Seas and Bay of Biscay region are found in two locations: in the western area of the British Isles, and the central part of the Bay of Biscay (Mahé and Poulard 2005). Results from the annual Spanish international bottom trawl survey suggest that it was caught in very low abundance in the Cantabrian Sea and Galician waters prior to 2000, but has only been found in low numbers since (ICES 2012). It also occurs in the landings at the important fishing harbours of Matosinhos and Peniche in western Portugal (Bordalo Machado et al. 2004).Mediterranean SeaThis species occurs throughout the Mediterranean Sea, including the Black Sea. It is one of the more abundant elasmobranch species in the bycatch of the trawl fishing grounds of the Gulf of Gabès (Kadri et al. 2014) and occurs along the coast of Languedoc (Capapé et al. 2007).

population:
Northeast AtlanticSpecies-specific survey and catch data suitable for estimating population trends span only the most recent two generations, and the survey methods vary across regions within the Northeast Atlantic making it difficult to derive a synoptic subpopulation trend. These more recent surveys spanning only approximately the past two generations need to be viewed in the context of the earlier longer-term declines in catch rate and range. Scientific trawl surveys are coordinated under the auspices of the International Council for the Exploration of the Sea (ICES) Working Group on Beam Trawl Surveys and the International Bottom Trawl Survey Working Group. These are the main data sources used by the ICES Working Group on Elasmobranch Fishes to evaluate stock trends in the absence of formal quantitative stock assessments. These surveys are summarized below. It is noted that most have been reported as nominal catch per unit effort and that data refer to all individuals (adults and juveniles) caught.Catch per unit effort (CPUE, all individuals) of this skate in the fishery-independent North Sea International Bottom Trawl Survey has been stable in recent years, with a mean CPUE for 2010 to 2011 of approximately 0.2 individuals per hour in winter, falling slightly below the 2005 to 2009 mean range (+/- standard deviation), and approximately 0.3 in summer, falling within the 2005 to 2009 mean range (ICES 2012).The trend in mean catch rate during fishery-independent surveys in the eastern English Channel (all individuals) increased between 1993 and 2011, from approximately three to nine individuals per hour (ICES 2012). Mean CPUE in 2011 (approximately nine individuals per hour) was almost double that for the period 2005 to 2009 (approximately five individuals per hour). Similarly in the western English Channel Carhelmar survey, the mean number of individuals caught per 30 minute tow, while highly variable, has increased from around 0.5 in the initial part of the time series to about 0.8 in recent years (Burt et al. 2013). This recent trajectory survey, however, should be viewed in the context of an historical longer-term population reduction (McHugh et al. 2011).In waters west of Scotland, CPUE of the fishery-independent Irish Groundfish survey increased to a mean of approximately 1.7 individuals per hour between 2010 and 2011, which is more than double that in 2003, of less than 0.7 individuals per hour (ICES 2012).The fishery-independent French IBTS (EVHOE) between 1997 and 2004 generally indicated stable catch rates of approximately five individuals per square kilometre in the Celtic Sea and Bay of Biscay (Mahé and Poulard 2005), but catch rates declined in 2009-2011 (ICES 2012). It should be noted, however, that catches of this magnitude were seen earlier in the time series and this survey generally operates further offshore than the main areas of abundance of this species.The mean fishery-independent CPUE of this skate in the Irish Sea and Bristol Channel in 1993 was more than three individuals per hour, compared with more than seven individuals per hour in 2011. Results from the fishery-independent annual Spanish international bottom trawl survey indicated no significant difference between annual mean biomass in the Cantabrian Sea in recent years (ICES 2012). Overall, scientific trawl surveys operating in northern European waters show that the relative abundance of Thornback Skate in research surveys has been stable or increasing in recent years. It should be noted that these CPUE data have been standardized in terms of locations fished and gear, but have not accounted for potential environmental influences on species range (process error) and that fully standardized CPUEs are preferable for estimating population trajectories to avoid issues such as hyperstability.A high frequency long-term trawl survey using standardized gear and vessel in the western English Channel revealed that steep declines in abundance of large fish including skates occurred in the western English Channel from the 1950s onwards, with catches between 1911 and the 1950s much higher (e.g., Genner et al. 2010). An inshore survey of two areas off Plymouth undertaken between 1913 and 1922 compared with 2008-2009 showed mean CPUE of Thornback Skate to be about two orders of magnitude lower in recent times than a century ago (McHugh et al. 2011). The number and mean size of this species caught by recreational anglers and reported to the Welsh national angler’s club, declined significantly between 1976 and 2002 (Richardson et al. 2006). No Welsh-caught specimen-sized individuals were reported to the club from 2000 to 2002. Correspondingly, the angling Landings Per Unit Effort (LPUE) rates for ray species declined significantly over the period and landing rates decreased by over one kilogram per hour every six years.Trammel, longline and trawl fisheries operating in the Bay of Biscay and Iberian waters all increased in average LPUE of this skate between 2009 and 2011 (ICES 2012). French and Spanish landings from the Bay of Biscay ranged from 93 tonnes (t) in 2002 to 143 t in 2011, showing variation through the years with an overall increase (ICES 2012). LPUE for the Basque Country (Spain) otter bottom trawl fleet has increased from approximately 13 kilograms per day in 2002, to approximately 21 kilograms per day in 2011 (ICES 2012). A notable increase was seen in reported Portuguese landings of the species from Iberian waters (351 t in 2003 to 814 t in 2011; ICES 2012). There are four synoptic modelling studies that seek to integrate the fragmented and uncertain observational and life history information to estimate fishing mortality rates of this species in the North Sea. All studies suggest that historic and recent fishing mortality far exceeds sustainable levels, and indeed the levels are high enough to explain the local absence of this skate from parts of the North Sea (e.g., the southeast area; Fock 2014). Based on catch curve analysis of catch taken from 2000 to 2006 in the North Sea, 38% of Thornback Skate that are approximately 64 cm in length (approximately five years of age) were fished each year (Wiegand et al. 2011). This study inferred that if current fishing patterns continued, it could result in a projected population decline of 90% within 30 years (comparable to three generations). The estimates of total mortality from a catch curve analysis, however, require the assumption of constant selection over the ages used. In the North Sea, there is a disconnect between the modelling studies estimating current and sustainable fishing mortality and the nominal research survey indices over the more recent two generation spans. It is recommended that standardized CPUE indices be developed and are reconciled against the various quantitative methods of estimating of fishing mortality and sustainability. Specifically, the CPUE indices currently used should account for environmental variation in the distribution and abundance of this species. Piet et al. (2009) used a swept area method that accounted for gear-, species- and size-dependent catch efficiency to estimate the mortality of target and non-target species. They estimated that the total mortality of this skate was 78% (60% due to beam trawls). Fock (2014) estimated fishing mortality using a cohort-based catch curve analysis for ages one to seven based on survey CPUE. Historically, fishing mortality was very high in the southeast North Sea from 1902-1932 (instantaneous fishing mortality = 1.03 which is a mortality rate of 35% per year). This mortality rate is similar to the subsequent decline rate of Thornback Skate inferred from a comparison of the replacement rate to the total mortality inferred from a catch curve (23% decline per year, 1992-1995) by Walker and Hislop (1998). In summary, the recent estimated trends in relative abundance from a range of research trawl surveys, including some of over 20 years duration, indicate that catch rates (all individuals) have increased in core parts of the geographic distribution. However, these data only cover a period of approximately two generations and it is inferred that the recent increase has followed a longer-term decline. It is also inferred that the geographic range may have declined overall, but by no more than 30% over the three-generation period.Mediterranean SeaSurveys conducted on the Italian and African sides of the Strait of Sicily between 1985 and 2002 revealed decreasing trends in Thornback Skate biomass on the African continental shelf, declining by 55.6% from approximately 45 kilograms per square kilometre to 20 kilograms per square kilometre (Garofalo et al. 2003). This decline is consistent with an increase in fishing pressure. Although no effort data are available prior to 1994, it may be assumed that intensive exploitation in this area started in the early 1990s, when the distant fishery was developed. On the Italian side of the Strait of Sicily, biomass decreased until 1990, though there were trends of increasing abundance from 1985-2002. These findings are in agreement with the decreasing trend of fishing effort that occurred in the same area. Following the structural changes in the Mazara del Vallo fleet in the early 1990s, fishing effort on the Italian side has declined gradually by approximately 63% overall, from over 30,000 fishing hours in autumn 1990 to approximately 11,000 fishing hours in autumn 2002 (Garofalo et al. 2003). Overall biomass levels were lower on the Italian side than the African side, owing to a history of higher Italian fishing effort.Starting at the beginning of the 1980s, increasing differences in abundance of populations of skates (Raja spp., the commercial category including Thornback Skate) between the Italian and African side of the Strait of Sicily have been reported, and were attributed mainly to the strong disparity of the exploitation level between the two fisheries (Andreoli et al. 1982): the Italian side was heavily fished for decades, whereas the exploitation on the African side was then just at the initial phase of development (Bottari et al. 2013). Specifically, the Italian-side versus African-side density indices (15 versus 98 individuals per km2), biomass indices (13.2 versus 49.2 kilograms per km2) and frequencies of occurrence (20% versus 71%), differed significantly. Present results tend to confirm the extreme rarefaction of the species on the Italian side and a more healthy status towards Africa. Presently, a minimum landing size for Raja spp. has not been determined by European Union (EU) regulations or national by-laws. In this area skates seem close to local extinction (Bottari et al. 2013).Trawl surveys of the Gulf of Lions (Aldebert 1997) observed a noticeable decline in landings of Thornback Skate at the Port of Sète from 1964 to 1996. Poisson (2011) reports further declines in landings for the same port in more recent years. The reduction in landings is estimated as greater than 75% over 32 years.On the Hvar expedition (1948-1949), Thornback Skate was very abundant in the Adriatic Sea, with an average abundance index of 65.25 kilograms per km2 (Krstulovic Sifner et al. 2009). In the same area, the average abundance index of the species in the MEDITS survey (1996-2006) was 1.96 kilograms per km2. During the Hvar expedition, the species was encountered at 80.8% of the stations sampled, while on the MEDITS survey it was found at only 6.1% of all sampling stations that overlapped accordingly. Although it must be noted that there were differences in the gears used, these figures indicated a reduction of 74.7% in the distributional range of the species in the Adriatic Sea, and a decline of 97% in the mean abundance index.In the Aegean Sea, the number of individuals per km2 declined alongside the probability of presence between 1998 and 2004 (Maravelias et al. 2012). Following this, both measures have recovered somewhat since 2005, though the levels of the late 1990s are as yet not recovered. The reported decline in abundance of the species in the Aegean Sea between 1998 and 2004 can be attributed, at least partially, to trawling fishing pressure, which is generally more intense at depths between 50 and 300 metres where this species typically occurs (Maravelias et al. 2012).In summary, research trawl surveys in the Mediterranean Sea from 1994 to 2006 suggest a stable index of abundance (kilograms per km2) for Thornback Skate in most of the Geographic Sub-Areas (GSAs), and it is inferred to have been stable from 2006 to 2015. However, other data sources suggest a historic decline and it is inferred that there has been a longer-term decline in geographical extent.

habitat:
This skate is a demersal coastal species, which inhabits a variety of substrates, including mud, sand, shingle, gravel and rocky areas, in water down to 300 m, although it is most abundant in 10–60 m of water off coastal areas (Wheeler 1969, Stehmann and Bürkel 1984). In the Mediterranean Sea, the main depth range is 100-300 m.Ryland and Ajayi (1984) estimated maximum age and length at 12 years and 104.7 cm total length (TL), respectively. Studies of specimens from the southern North Sea have shown this species to have a maximum length of 118 cm for females and 98 cm for males (Holden and Vince 1973, Walker 1998), although specimens may attain 130 cm TL. The size at maturity for females and males have been estimated at 45–50 cm disc width (DW) and 38–44 cm DW (Fitzmaurice 1974); 85 cm TL (54 cm DW) and 75 cm TL (48 cm DW) (Capapé 1976); 45 cm DW and 42 cm DW (Nottage and Perkins 1983) and 59 cm TL and 60 cm TL (Ryland and Ajayi 1984), respectively. This skate first spawns in its fifth year (Ryland and Ajayi 1984). The fecundity in British waters has been estimated at 150 eggs per year (Holden et al. 1971), 140 eggs per year (Holden 1975) and 100 eggs per year (minimum of 62–74) (Ryland and Ajayi 1984) although it may be as low as 48 (Ellis and Shackley 1995). Eggs are laid during February to September (Holden 1975) with a peak in May and June. However, this is for the population as a whole and the egg-laying period for individual fish may be shorter. Development lasts 16–20.5 weeks depending on temperature (Ellis and Shackley 1995). The young hatch at 10–13 cm TL. The nursery areas used are coastal areas (e.g. the Wash and Thames estuary in the UK). Capapé (1976, 1977) estimated a fecundity of 70–167 eggs per year in Tunisian waters. It may not be a continuous spawner (Serra-Pereira et al. 2011). About 35 eggs are released per clutch. During the spawning season, a total of four batch episodes occur indicating that the total fecundity may be approximately 136 eggs per female. In Portuguese waters, between 2003 and 2008, Thornback Skate spawns year-round, though mainly between May and January (Serra-Pereira et al. 2011). Females attain length at 50% maturity (L50%) at 78.4 cm TL and males at 67.6 cm TL, at ages of 7.5 and 5.8 years, respectively. The smallest mature female was 69.9 cm TL, while the smallest mature male was 59.0 cm TL. There have been several estimates of the length at maturity (McCully et al. 2012 and references therein). Walker (1998) estimated length at 50% maturity to be 77 cm TL (eight years) for females and 68 cm TL (seven years) for males. More recent studies from British waters indicate that the length at first maturity for Thornback Skate is about 47 cm TL, with L50% attained at 66.6 cm TL (males), 74 cm TL (females, North Sea) and 78 cm TL (females, Celtic Sea) (McCully et al. 2012). In the Ligurian-North Tyrrhenian sea, L50% was estimated at about 78 cm TL, and 66 cm TL in males (Barone 2009). The L50% was 67 cm TL (six years) and 81 cm TL (eight years) for males and females, respectively in the Gulf of Gabès, Tunisia (Kadri et al. 2014). The oldest recorded Thornback Skates are typically about 15 years (Walker 1999, Kadri et al. 2014).Regional differences may exist in the reproductive strategy of the species, namely on the duration of the spawning season, length-at-first-maturity, and fecundity, which may be related to a more intense fishing pressure in northern European waters (Serra-Pereira et al. 2011). Nevertheless, differences in the length-at-maturity should be interpreted with care, as differences in maturing staging are apparent in some of these studies (McCully et al. 2012). Given that females appear to reach L50% at seven to eight years and live for at least 15 years, the generation time is estimated at 11.5 years.The migratory habits have been studied by Steven (1936) who found that very little movement occurred, especially in young fish, with 71% of tagged fish moving less than five miles. Fish tagged in the southern North Sea also showed a sedentary pattern, with 80% being recaptured within 40 nautical miles of their release position (Walker et al. 1997). The recapture percentage was nearly 30%.

threats:
Northeast AtlanticThornback Skate is a very important component of demersal fisheries in most European waters and is taken by trawl and gillnet, particularly as bycatch. There is also some directed longlining and netting for the species. Historical species-specific landings are not known, as landings of all skates were combined. It is also regularly caught by recreational anglers, although mortality from this source of fishing pressure is likely to be of little effect for the population as a whole, particularly in areas where catch and release is practised.This skate is of high value in the southwest North Sea, taken by target fisheries of the North Sea ecoregion and as bycatch by fisheries targeting sole (beam trawl and gillnet) and cod (trawl, gillnet and longline) (ICES 2012). There is a possibility of misidentifications in some of the recent International Bottom Trawl Surveys between Thornback Skate and Thorny Skate (Amblyraja radiata). There are localised, inshore fisheries targeting Thornback Skate, using longline and tangle nets, and trawl fisheries targeting various skate species in the southern Irish Sea and Bristol Channel. There are no specific regulations restricting fishing mortality for this species in this region.Mediterranean SeaIn the Mediterranean Sea this species is threatened by incidental capture in trawl fisheries targeting Rose Shrimp (Parapenaeus longirostris), Curled Octopus (Eledone cirrhosa) and European Hake (Merluccius merluccius). There are no specific regulations restricting fishing mortality for this species in this region. In the Southern Ligurian Sea-Northern Tyrrhenian Sea, a recent assessment of stock status suggest that the current fishing mortality rate for this species is much higher than what is sustainable (Abella et al. 2011). Simple demographic analyses estimate a relatively high productivity compared to other shark species, and suggest that changes in juvenile survival are likely to produce the biggest changes in population growth rate. The low selectivity of bottom trawl nets in the area and fleets operating over all the depth range where the species inhabit produces a very small size of full recruitment to the fisheries (Serena 2014).Climate change has influenced the distributions of many European fish populations, including this skate, in a manner that may influence the assessment of population trends and the potential viability of subpopulations (Perry et al. 2003, Dulvy et al. 2008, Ben Rais Lasram et al. 2010, Genner et al. 2010, Simpson et al. 2011).

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 metres was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).Northeast AtlanticSince 2008, the European Commission has obliged member states to provide species-specific landings data for the major North Sea species, including Thornback Skate, in order to improve understanding of skate stocks in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009), and has been ongoing since 2008 (CEC 2013). There is no species-specific quote regulating fisheries of this species.The Portuguese Administration adopted a national legislation in October 2011 (Portaria no 315/2011) that prohibits the catch, the maintenance on board, and the landing of any skate species belonging to the genera Raja spp. or Leucoraja spp along the whole continental Portuguese Exclusive Economic Zone during the month of May (ICES 2012). Additionally, each fishing trip is allowed a maximum of 5% bycatch, in weight, of those species to be maintained on board or landed.Thornback Skate is listed as a threatened and declining species on the Oslo and Paris Conventions for the protection of the marine environment of the Northeast Atlantic (OSPAR 2008, ICES 2012).Several of the UK’s local Inshore Fisheries and Conservation Authorities (IFCA) have by-laws for a minimum landing size (e.g. 40 cm DW in the Southern and the Kent and Essex Districts). Such localised management initiatives will not, however, be of significant effect in conserving regional populations. Due to European rajid fisheries being a component of multispecies fisheries, which also target several species of flatfish and gadoid, gear restrictions using mesh size is not a viable management measure. The use of larger, square mesh in trawls, however, may improve discard survival (Enever et al. 2010).Mediterranean SeaIn the Mediterranean Sea fisheries, stock management is based on controlling fishing capacity and fishing effort and on the enforcement of technical measures, such as mesh size, area closures, and seasonal bans, which takes place for 30 days between August and September (Dimech et al. 2008, Bottari et al. 2013).

useAndTrade:
There are localised and targeted fisheries for this species.

redListAssessors:
Ellis, J., Dulvy, N., Walls, R. & Serena, F.


taxonomicNotes:
Raja maderensis, or a very similar species, is found in the Azores. The taxonomy and relationship of skates on these islands should be assessed. This species is now thought to be distinct from similar specimens from the Canary Islands and West Africa (Ebert and Stehmann 2013).

redListCategoryRationale:
Madeira Skate (Raja maderensis) is endemic to Madeira (Portugal) and the Azores (Portugal) in the Eastern Central Atlantic. It is found on the upper shelf and slope down to at least 150 m depth. The species attains 70-80 cm total length but its biology is poorly known. The continental shelf and slope off Madeira and the Azores is too rough for trawling, but this species is taken as regular bycatch in bottom longline fisheries and is mostly discarded, survival from which is unknown. In the Azores, skate landings have increased recently. The species has a restricted number of locations (less than five), and discard survival after bycatch is unknown; it therefore qualifies as Vulnerable under criterion D2. Research is required on taxonomy, distribution, population size, life-history and fisheries related mortality.

range:
This skate is apparently only found on the shelf and upper slope of Madeira (Portugal) (Stehmann 1971, 1973, 1979; Stehmann and Bürkel 1984). Reports of this species elsewhere in the Eastern Central Atlantic are misidentifications, and the identity of a similar form in the Azores still needs to be clarified (see ‘Taxonomic Notes’ section). It may also occur on submarine banks, such as Great Meteor Bank (Ebert and Stehmann 2013).

population:
This skate is relatively common in the Azores, although it has very restricted local populations (Ebert and Stehmann 2013). It is likely to have an extent of occurrence (EOO) of < 5,000 km² as the combined shelf area of the Exclusive Economic Zone (EEZ) of Madeira (333 km²) and the Azores (1,955 km²) is 2,288 km² (EEZ estimate from the See Around Us Project website). The species is currently known to exist in only two locations, and is subject to unregulated fishing mortality in both, albeit a non-target species. The combination of a small EOO (< 5,000 km²) and presence in only two locations with largely unmonitored, unregulated fisheries in operation leads to suspicion of a decline in the number of mature individuals. While species with no commercial value can generally be considered less susceptible to fishing, and there are no catch or landings data available for this species, there is also no information to suggest its post-release survival rate. For this reason, it is necessary to assess the situation precautionarily under the assumption that it may not survive after being discarded. This skate is considered very rare, or perhaps absent from waters southwest of the Azores (Bloomfield et al. 2011). Additionally, the Azorean Spring Demersal Longline survey confirmed very low numbers of the species (Pinho 2006).

habitat:
This species is found on the upper shelf and slope at depths down to 150 m on both soft and hard substrates (Stehmann 1971, Stehmann and Bürkel 1984). Like other skates, reproduction is oviparous. It attains a maximum size of 70-80 cm total length (TL) and probably matures at > 50 cm TL, but no other information is available on its biology (Ebert and Stehmann 2013).

threats:
The continental shelf and slope off Madeira is too rough for trawling and this species is caught as bycatch in line fisheries and mainly discarded (Ebert and Stehmann 2013). However, discard survival is unknown and skate catches are increasingly reported, particularly from the Azores Islands. No catches are reported from Madeira (SAUP 2014). 

conservationAction:
There are no species-specific measures in place, and the European Union total allowable catch limitations for skates and rays do not extend to the Azores or Madeira. Further information is required on the taxonomy, population size and trends, life history and fisheries related mortality, including post-release survival. 

useAndTrade:
The species is very rarely marketed. There is no target fishery in Madeira (P. Wirtz pers. comm. 2008).

redListAssessors:
Dulvy, N.K., Walls, R.H.L., Buscher, E. & Stehmann, M.F.W.


taxonomicNotes:
There is some potential for confusion with regards the common names of this species. In some areas, Smalleyed Ray may be called Painted Ray or Sandy Ray, though these common names are also used for undulate ray Raja undulata and Leucoraja circularis respectively.

redListCategoryRationale:
European regional assessment: Near Threatened (NT) Smalleyed Skate (Raja microocellata) has a much smaller range than most other common European skates. It is found on the continental shelf, mostly at depths of less than 100 m. It favours sandy bays and is only recorded as abundant at a few sites (e.g., Bristol Channel and Bertheaume Bay). This species is taken as bycatch in trawl and set net fisheries, with most landings from the Bristol Channel and it is also commercially important in some parts of the English Channel. Given its restricted, patchy and fragmented geographic distribution, local subpopulations are potentially vulnerable to decline by overfishing, habitat degradation and other anthropogenic disturbance. Fishery-independent population trend data for mature individuals are limited and careful monitoring is required to accurately determine population trends. Catch rates in a scientific trawl survey (1993−2013) of the Bristol Channel have been stable over the longer time series, although catch rates (all individuals) have declined in the most recent years. The stability of this population is partly due to the conservation measures in place, such as the Total Allowable Catch management of skates and rays. Given the declining catch rates in more recent years, and the fact that the cessation of the conservation measures would result into the species meeting the threshold for a threatened category under Criterion A, this species is assessed as Near Threatened based on its dependence on ongoing conservation actions. Closer monitoring of this stock should be undertaken.

range:
This species’ range is smaller than many of the more common European skates. It is restricted primarily to the Atlantic coasts of northwest Europe, from the British Isles southwards to Gibraltar and northwest Africa from Morocco and Western Sahara. This species is mainly concentrated in the Bristol Channel (Ellis et al. 2005a), with some larger individuals occurring in slightly deeper waters of the Celtic Sea and specimens are occasionally caught in the Irish Sea (ICES 2012). There are also localised concentrations in parts of the western English Channel (e.g., around Jersey; Ellis et al. 2011), and in some inshore areas of Ireland (Fahy and O'Reilly 1990). It is unclear as to whether the subpopulation in the eastern English Channel overlaps with that of the western English Channel (Ellis et al. 2011). The species only occurs sporadically in the eastern English Channel, but is generally absent from the southern North Sea (Ellis et al. 2005b). It has also been reported in French landings from the Bay of Biscay (ICES 2012). Its depth range is one to 100 m.

population:
Over much of its geographic range, this skate is relatively rare. Within United Kingdom (UK) waters, it is only reported occasionally in the Irish Sea and North Sea, and caught in low numbers in the English Channel. It is also locally abundant in certain areas; and one of the most abundant skates occurring in the Bristol Channel (International Council for the Exploration of the Sea [ICES] Division VIIf), Bertheaume Bay off Brittany, and off southeast Ireland (Fahy and O'Reilly 1990, Rousset 1990, Ellis et al. 2005a, 2005b). Hence, this species seems to have a fragmented population, possibly due to the fragmented nature of its favoured inshore habitat. No formal stock assessments have been undertaken for this skate. Catch rates in beam trawl surveys of the Bristol Channel (1993−2013) increased over the initial part of the time series (Ellis et al. 2005a), and although it has declined in recent years (ICES 2013), recent catches are similar to those observed at the start of the time series. It should be noted that these catch rates are calculated for all individuals and the survey equipment is likely to sample immature fish more effectively, therefore fishery-independent data for mature fish are limited.In the Great West Bay of the western English Channel, the mean number of individuals caught per 30 minute trawl tows was low and highly variable between 1989 and 2010. Two peaks of around 0.12 individuals were caught per tow in 1997 and 2010, while distinct troughs of between 0.015 and zero individuals were caught per tow in 1999 and 2008, respectively (Burt et al. 2013). It is unclear if the population in the western English Channel is part of the Bristol Channel subpopulation or a separate subpopulation. French landings from the Bay of Biscay region between 1999 and 2010 were very low at zero to three tonnes (t) each year (ICES 2012). Portuguese landings from Iberian waters went from 78 t in 2003, to 105 t in 2006, then 51 t in 2009. Landings per unit of fishing effort increased between 2008 and 2011 for the trammel net fisheries in the Bay of Biscay and Iberian waters. The population trend is estimated to be stable based on catch rates of all individuals in a scientific trawl survey over the period 1993−2013, which broadly equates to a three-generation period. Catches have declined in recent years, and continued monitoring is required.

habitat:
Smalleyed Skate (Raja microocellata) is most abundant in sandy bays and other inshore sandy areas (Stehmann and Bürkel 1984), particularly along sandbanks (Kaiser et al. 2004). Juveniles tend to occur in shallow water, with larger individuals more abundant further from shore, though the species is uncommon at depths greater than 100 m (Ellis et al. 2005b). This is a small to medium size skate. It begins to mature at 57.5−58.0 cm total length (TL) and attains a maximum length of 91 cm TL (Ryland and Ajayi 1984). In the western English Channel off Jersey, UK, males reach first maturity at 64 cm TL and all males greater than or equal to 77 cm TL are mature (Ellis et al. 2011). The length at 50% maturity is 68 cm, which contrasts with previous estimates of 70 cm and 100 cm reported for males and females, respectively, by Dorel (1986). In the British Isles, the smallest mature male and female observed from trawl surveys were 66 and 73 cm TL, respectively, with a length at 50% maturity of 69 and 77 cm TL (McCully et al. 2012). The largest immature male and female individuals found during these surveys were 74 and 83 cm TL, respectively. Little is known about the reproduction of this species. Fecundity is estimated to be 54−61 eggs per year, with egg-laying activity peaking between June and September. Size at birth is approximately 10 cm TL. Maximum age is reported to be nine years (Ryland and Ajayi 1984), and the generation length of this species is estimated to be 6.8-8.5 years.

threats:
In the UK, this species is commercially important in ports of South Wales, Devon and Cornwall. It is also taken as bycatch in trawl and set net fisheries, with most landings from the Bristol Channel. Landings of this species from the North Sea, as reported by France, are likely the result of misidentification or incorrect use of species codes. Furthermore, landings of Sandy Skate (Leucoraja circularis) from the western English Channel and Bristol Channel, as reported by Belgium, likely refer to Smalleyed Skate (Raja microocellata), as both species are known as ‘Sandy Ray’ (ICES 2012, Silva et al. 2012). It is unclear as to whether current exploitation levels in the Celtic Seas are sustainable or not (ICES 2012). Exploitation levels in areas further south are not known. Some sand banks in the Bristol Channel are dredged to supply the aggregate industry and the potential consequences of this activity for this skate are unknown (Fowler et al. 2005). Due to its restricted distribution, inshore habitats and overall scarcity, albeit with areas of localised abundance, it may be at risk from overfishing and habitat disturbance. 

conservationAction:
No species-specific management or conservation measures are currently in place for this skate. In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).There is a minimum landing size of 40 cm for skates and rays taken from the inshore waters of South Wales. More generic management measures for demersal fisheries (e.g., mesh size regulations) may be beneficial. Since 2008, the European Commission has obliged member states to provide species-specific landings data for all major North Sea species, including Smalleyed Skate, in order to improve understanding of populations in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009, 2013).

useAndTrade:
In the UK, this species is commercially important in ports of South Wales, Devon and Cornwall.


redListCategoryRationale:
European regional assessment: Least Concern (LC)Brown Skate (Raja miraletus) is a wide-ranging, relatively small, fairly fecund species found predominantly on the continental shelf, but occurring down to 530 m in depth. Apparently the Northeast Atlantic and Mediterranean stocks are separate subpopulations. Although this species is exploited throughout much of its depth range, there appears to be no significant threat from current levels of exploitation. This is one of the most abundant skates in the Mediterranean Sea, and although surveys have shown temporal fluctuations of abundance, this species appears to be stable in most parts of the region, including over longer time scales from 1948-1999 in the Adriatic Sea. Its small body size and early maturation suggests its overall resilience to exploitation, and together with relatively stable catches, it is assessed as Least Concern in the region.

range:
In European waters, Brown Skate (Raja miraletus) is found in the Northeast Atlantic and Mediterranean Sea, where it apparently forms two distinct subpopulations between these areas. In the Northeast Atlantic, it ranges from northern Portugal to Madeira (Stehmann and Bürkel 1984). It occurs in the Bay of Biscay region and Iberian waters (ICES 2012), including at fishing ports Matosinhos and Peniche, where the major landings of Rajidae in mainland Portugal occur (Bordalo Machado et al. 2004). Baeta et al. (2010) found the species only occurred in Setúbal and Sesimbra fishing harbours off the Portuguese west coast during the colder months, with highest abundance in winter.  A common small skate in the Mediterranean Sea (Hemida et al. 2007, Serena et al. 2010), it is one of the most frequently landed cartilaginous fish from bottom trawls in the Adriatic Sea (Jukic-Peladic et al. 2001). The species is also a regular component of discarded fish in the bottom trawling fishery in the Gulf of Gabès (Kadri et al. 2014). Brown Skate occurs also in waters north of the Balaeric Islands (Massutì and Moranta 2003). This skate exhibits a discrete distribution along the African shelf and Adventure Bank in the Strait of Sicily, as well as lower abundances at the Malta Bank, excluding the Maltese Exclusive Fishing Zone (Garofalo et al. 2003). It appears to be absent from the coastal waters of the central Sicilian shelf. Its depth range is 10-530 m.

population:
This species is found predominantly on the shelf and appears to be one of the most abundant skates in the Mediterranean Sea. It was consistently caught in northern Mediterranean (MEDITS project) trawl surveys conducted since 1994 at depths between 50 and 800 m (Baino et al. 2001). This species was one of the most frequently recorded rays during these surveys, captured in 422 out of 6,336 survey tows from 1994-1999. It was found throughout the survey area with greatest catch rates in the western central area (Tyrrhenian, Corsican, Sardinia and Sicily coasts) (Baino et al. 2001). Although fluctuations of abundance occurred along the years, biomass of this species appears stable in most parts of the Mediterranean Sea (Relini et al. 2000). MEDITS surveys suggest a stable abundance index for almost all Italian Geographical Sub-Areas (GSAs; Serena 2014).Over longer time scales from 1948-1999 in the Adriatic Sea abundance appears to be stable, being more abundant in the north and central areas of the Adriatic Sea, where it is consistently captured in 4% of hauls (Jukic-Peladic et al. 2001, Marano et al. 2003). This species was not present in earlier GRUND surveys (1985-1992) in the southern Adriatic but since 1992, it is consistently captured in >2% of hauls (Marano et al. 2003).In general, abundance of skates off the Balearic Islands is higher than that reported from the Iberian Peninsula (Massutì and Moranta 2003). It is also similar to the maximum abundance reported from other western Mediterranean areas off Corsica and Sicily for Brown Skate.A decrease of approximately 30%, from 27 to 15 kg/km2, in Brown Skate biomass was reported on the African shelf off Libya between 1997 and 2000, followed by a slight increase in 2001 (Garofalo et al. 2003). In the Straits of Sicily, the same authors found Brown Skate biomass relatively stable, with an overall increasing trend between 1986 and 2002 of 55.6% from approximately five to nine kilograms per squared kilometer (Garofalo et al. 2003). However, overall levels of biomass in the northern part of the Straits were lower than that off Libya, likely due to intensive fishing activity since the 1970s. The overall increase in abundance of Brown Skate in this area is therefore in line with the decreasing trend in fishing effort in this area. There has been a reduction in fishing effort in the northern part of the Strait of Sicily, with values falling 63% from over 30,000 fishing hours in 1990, to approximately 11,000 fishing hours in 2002.

habitat:
This small skate is found on the continental shelf, from the shallows to 530 m depth, but mainly at depths of 50-150 m (Relini et al. 1999, Serena 2005). It is common on a range of substrates, from sandy-muddy bottoms to Posidonia oceanica seagrass beds. Maximum size is reported at 60 cm total length (TL) in the Mediterranean. Data from the Mediterranean suggest that females mature at 39-44 cm TL and males at 36-40 cm TL (Jardas 1973, Relini et al. 1999, Ungaro 2004). Both males and females reach maturity at two to three years of age and live for a total of 10 years (Abdel-Aziz 1992). It is only found at depths greater than 50 m, and is most abundant at 100 m and in colder autumn (Baeta et al. 2010).A study carried out by Kadri et al. (2012) in the Gulf of Gabès, found that the smallest mature male Brown Skate was 28 cm TL and the largest immature male was 43 cm TL. The length at 50% maturity (L%50) for males was estimated at 41.8 cm TL (27.10 cm disc width DW). The smallest mature female was 33 cm and the largest immature one 48 cm TL, reaching L50% at 34.31 cm TL (21.91 cm DW). The youngest mature males and females were two and four years old, respectively. The age at 50% maturity was estimated to be three years for males and four years for females. Egg-bearing females occurred in all months, reaching a maximum during spring and summer. Females and males grew to approximately the same size, with maximum length slightly greater for males than for females.  The species is egg laying, with egg cases laid throughout the year with a peak in spring (Relini et al. 1999). Size at birth in the Mediterranean Sea is 10-11 cm TL (Serena 2005). Demographic modelling suggests the productivity of this skate is relatively high if compared to other species, and that the population growth rate is strongly dependent of the survival rates of juveniles (Serena 2014). Brown Skate has an intrinsic population growth rate of 0.176 year-1, a generation time of 5.69 years, and a time needed for doubling population size of 3.94 years (Serena 2014).

threats:
The small maximum size of this species suggest it is likely to have a relatively short generation time and a relatively high capacity to replace numbers lost to exploitation (Dulvy et al. 2000, Stevens et al. 2000). It is commonly caught as bycatch of bottom trawl fisheries in the Mediterranean Sea (Serena 2005), but there is no evidence to suggest that it has declined in this area. The species is occasionally caught by fixed gears also (nets, hooks). Most of the specimens are discarded at the sea while the bigger individuals are occasionally marketed.This species is part of the bycatch of the bottom trawl fishery off the Balearic Islands, with a high proportion of individuals discarded (Massutì and Moranta 2003).The size composition of scientific catches is mainly represented by age classes 1+, 2+, 3+. Higher density of catches corresponds to areas where continental shelf is more extensive, with a yield of 9.6 kg/km2 (Tuscan archipelago, Sardinia and Sicily).Trammel net bycatch samples taken between 2004 and 2005 from Setúbal and Sesimbra on the Portuguese west coast, caught 83 individuals weighing a total of 23.4 kilograms (4.08 individuals or 1,151.78 g per 10,000 m of net) (Baeta et al. 2010). Of this, 63.9% was retained, either for marketing or consumption by fishermen, and the remaining 36.1% was discarded.

conservationAction:
Further research is needed to better evaluate population structure to improve stock assessment of this species. It is recommended that catches are monitored throughout its range to determine existence and status of the subpopulations.The Portuguese Administration adopted a national legislation in October 2011 (Portaria no 315/2011) that prohibits, along the whole continental Portuguese Exclusive Economic Zone, during the whole month of May, the catch, the maintenance on board and the landing of any skate species belonging to the genera Raja or Leucoraja (ICES 2012). Additionally, each fishing trip is allowed a maximum of 5% bycatch, in weight, of those species to be maintained on board or landed.

redListAssessors:
Dulvy, N.K., Walls, R.H.L., Abella, A., Serena, F. & Bradai, M.N.

redListContributors:
Smale, M., Ungaro, N., Tinti, F., Bertozzi, M., Mancusi, C. & Notarbartolo di Sciara, G.


taxonomicNotes:
There are no recent synonyms. In terms of identification, juvenile spotted rays can be confused with the morphologically similar blonde ray (Raja brachyura) and thornback ray (Raja clavata). Some spotted rays have fewer spots that are concentrated in the centres of the wings and can be misidentified as cuckoo rays (Leucoraja naevus).

redListCategoryRationale:
European regional assessment: Least Concern (LC) Spotted Skate (Raja montagui) is widespread in the inshore waters and shallow shelf seas of the Northeast Atlantic and southern Mediterranean Sea. Their small body size is likely to mean this species has greater resilience to fishing impacts compared to larger-bodied skate species. Populations appear to be stable throughout its range despite being commonly landed in fisheries. It is common in landings from fisheries and trawl surveys throughout much of the Northeast Atlantic and although accurate species-specific landings data are not available, catch rates in fishery-independent surveys indicate that catches are stable, possibly increasing in certain areas, and some of these surveys encompass the estimated three-generation period. Furthermore, there is ongoing management of the skate complex in this area. Therefore this species is assessed as Least Concern. Given intense trawling pressure within its range, future trends and bycatch levels should be closely monitored.

range:
The species is widely distributed in the Northeast Atlantic, ranging from Morocco in the south to the Shetland Isles and Skagerrak and Kattegat in the north, including the Mediterranean Sea (Stehmann and Burkel 1984, Bauchot 1987). Spotted Skate (Raja montagui) is found in the coastal area of the Norwegian Sea, and stocks probably continue throughout the North Sea, into the waters west of Scotland and into the eastern English Channel (ICES 2012). Additionally, the species occurs off the Faroe Islands, throughout the Bay of Biscay and in Iberian waters. It is also present in the Mediterranean Sea along the Algerian coasts (Bertozzi et al. 2003, Hemida et al. 2000). Its depth range is eight to 283 m.

population:
No formal stock assessments have been undertaken for this species. It is common in landings and trawl surveys throughout much of its range and although accurate species-specific landings data are not available, catch rates in fishery-independent surveys indicate that catches are stable, possibly increasing in certain areas. Northeastern AtlanticPreliminary studies of catch rates in beam trawl surveys in the English Channel and Irish Sea appeared stable when this species was last assessed (Ellis et al. 2005b), and International Bottom Trawl Survey (IBTS) data in the North Sea were also relatively stable (ICES 2006). These catch rates refer to all individuals caught and not just mature fish. The area of the North Sea occupied by this skate has varied in recent decades without a trend (ICES 2012). Catch by fishery-independent surveys in this ecoregion has increased since 2000, from a mean catch per unit effort of 0.25 individuals per hour to 1.1 in 2010. Martin et al. (2010) found a decreasing trend in mean density in the French Channel Groundfish Survey throughout the English Channel over the period 1988 to 2008. The mean density decreased by 93.3%, from 0.30 in 1988 to approximately 0.02 in 2008 during this survey (Martin et al. 2010). This skate may not be effectively sampled by the Grande Overture Verticale trawl used. Initial analyses of data from fishery-independent beam trawl surveys in the western English Channel (particularly in the Great West Bay area) suggest that recent fishery-independent catches have increased in relation to the preceding five years of decline, to 0.4 individuals per hour, although catch rates were greater at the start of the time-series (Burt et al. 2013, ICES 2013).The English and Welsh fishery-independent beam trawl surveys in the Celtic Sea and Bristol Channel catch reasonable numbers of Spotted Skate, reporting regular observations, with mature individuals taken on the offshore stations on coarse grounds. This survey indicates above average catches in the last two years. The French EVHOE survey generally indicated stable catch rates in the Celtic Sea (ICES 2013). Preliminary analyses of the Northern Irish fishery-independent survey of the Irish Sea also indicated stable or potentially increasing catches (ICES 2012), although this survey uses a rock-hopper trawl, for which the catchability may be low (ICES 2012). The Scottish fishery-independent survey off west Scotland also suggested stable or increasing catch trends (ICES 2012). Catches of this skate in the Irish Groundfish fishery-independent survey off west Scotland are increasing from low levels in 2008 (ICES 2012).Mediterranean SeaRetrieved in the Mediterranean Sea, exclusively in the westernmost area (Algerian basin). This species is always confused with the similar species Speckled Skate (R. polystigma) which is abundant in the whole western-central Mediterranean Sea (Cannas et al. 2008).

habitat:
Spotted Skate is most common on sandy sediments in coastal and shelf seas (Ellis et al. 2005a), though it may occur deeper in the southern parts of its range. Within the Northeast Atlantic it tends to occur in inshore waters and shallow shelf seas, in depths of eight to 283 m (Ellis et al. 2005a), though it is most abundant in waters less than 100 m. Juveniles tend to occur closer inshore on sandy sediments, with adults also common further offshore on sand and coarse sand-gravel substrates. Adults have an average total length of 60 cm (Bauchot 1987), and the maximum recorded length is 80 cm (Ellis et al. 2005b). It is an egg laying species, with a maximum fecundity of approximately 60 to 70 eggs per year (Holden et al. 1971, Walker 1999).The smallest mature male and female observed during bottom trawl surveys in the North Sea, English Channel, Irish Sea, Bristol Channel, and Celtic Sea were 40 cm and 49 cm, respectively (McCully et al. 2012). The length at 50% maturity (L50) for males was 50.3 cm, while that for females was 64.0 cm. The largest immature male and female were 66 cm and 70 cm, respectively. No significant differences in length at maturity between different regions of UK waters appear to exist. Given that females appear to reach L50 at four to seven years and live for at least seven years, the generation time is estimated at six to seven years.

threats:
The species is commonly landed in fisheries (though not often targeted) and its small body size suggests that it may be less affected by fisheries than larger-bodied skate species (Dulvy et al. 2000). It is often landed and confused with Blonde Skate (R. brachyura), and some of the data for these two species are confounded, which could hamper accurate assessments of these species (ICES 2012). The exploitation status is still unknown.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org).There is a minimum landing size of 40 cm disc width for skates and rays caught in some of the inshore waters of England and Wales, through local bylaws.Since 2008, the European Commission has obliged member states to provide species-specific landings data for the major North Sea species, including Spotted Skate, in order to improve understanding of skate stocks in the area (CEC 2008). In 2009, this obligation was extended to other ICES divisions, including the Celtic Seas (CEC 2009), and has been ongoing since 2008 (CEC 2013).Since 2009, Norway has a discards ban that applies to skates and sharks, as well as other fish, in the Norwegian Economic Zone. However, discarding of skates is likely to have continued, although the precise quantity is unknown (ICES 2012).Spotted Skate is listed as a threatened and declining species in the North Sea on the Oslo and Paris (OSPAR) Conventions for the protection of the marine environment of the northeast Atlantic (OSPAR 2008), although the rationale for this has been questioned. Further research should be conducted on the population size and trend of the species, and monitoring should be undertaken on the harvest trends of the species.

useAndTrade:
Skates are an important component of demersal fisheries in the Northeast Atlantic and this species is landed and sold (Dulvy et al. 2000, Holden 1977).

redListAssessors:
Ellis, J.R., Walls, R.H.L., Serena, F. & Dulvy, N.K.

redListContributors:
Ungaro, N., Tinti, F., Bertozzi, M., Pasolini, P., Mancusi, C., Notarbartolo di Sciara, G. & Fordham, S.


taxonomicNotes:
In some areas of the Mediterranean Sea (particularly along the Italian coasts) this species is probably misidentified with Raja montagui. Further investigation is required into this and morphometric and genetic studies are still in progress (Mancusi et al. 2005).

redListCategoryRationale:
Speckled Skate (Raja polystigma) is endemic to the Mediterranean Sea. This relatively small skate (up to 60 cm total length) mainly inhabits soft bottoms on the continental shelf at depths of 100-400 m. It shows a wide geographic range in the Mediterranean Sea (mostly western and western central areas) where it is moderately common. It is part of the bycatch in fisheries using bottom trawl nets, but is also fished with gillnets, longlines and handlines in artisanal fisheries. Although little is known of the effect of fisheries on population size, its entire range overlaps intensively trawled regions. Given its small-body size, it is likely to be able to withstand moderate levels of fishing pressure. Speckled Skate is therefore assessed as Least Concern, although the status of this endemic species should be monitored.

range:
Speckled Skate (Raja polystigma) is moderately common, endemic species throughout the Mediterranean Sea (Serena 2005), particularly in the western (Morocco, Spain and France) and western central areas (Tyrrhenia, Corsica, Sardinia and Sicily) (Baino et al. 2001, Ragonese et al. 2003, Florio et al. 2003, Follesa et al. 2003, Spedicato et al. 2003, Serena 2005, Mancusi et al. 2005), along northern African coasts (Stehmann and Bürkel 1984), and eastern Algerian coasts (Bertozzi et al. 2003). The species also exists in the southern Ligurian Sea (Vannucci et al. 2006) and around Asinara Island, northwest Sardinia (Catalano et al. 2007). It is rare in the Ionian Seas (Notarbartolo di Sciara and Bianchi 1998, Mytilineou et al. 2005). In the Adriatic Sea, it is rarely captured.

population:
The species is found predominantly on the shelf and has been caught in the MEDITS program at depths up to 500 m (Baino et al. 2001). It is the third most abundant skate species captured in trawl surveys performed in the south Ligurian and north Tyrrhenian Sea from 1985-2004 after Thornback Skate (R. clavata) and Brown Skate (R. miraletus). In this area it occupies a very wide depth range (20-633 m) but is more concentrated between 300 and 400 m. Important catches of juveniles were recorded occasionally. Most of the collected specimens measured between 12 and 49 cm in length (Serena et al. 2005).A study of commercial bottom trawl catch from 1995 to 2006 in the Aegean Sea caught a total of 203 specimens, with a mean catch per unit effort (CPUE) of 2.07 kilograms per hour, or 6.33 individuals per hour (Damalas and Vassilopoulou 2011). Of this catch, the majority was discarded (77.72% in weight; 93.60% in number) and the remaining fraction marketed (22.28% in weight; 6.40% in number). The same authors reported that fishery-dependent mean nominal CPUE of Speckled Skate in the central Aegean Sea has increased by 98.69% from a mean value of 0.01 individuals per hour (< 0.01 kg/h) between 1995 and 2000 to 0.71 individuals per hour (0.23 kg/h) between 2003 and 2006. Due to the high degree of morphological similarity with Spotted Skate (Raja montagui), in the past many Speckled Skate captured in the scientific surveys have been incorrectly identified as Spotted Skate (Cannas et al. 2008).

habitat:
The species is benthic, and it inhabits mainly soft bottoms from 100-400 m (Serena 2005), but with a wide depth range from 20-633 m. Both males and females are estimated to mature at 40-53 cm total length (TL) with a maximum recorded size of 60 cm TL (Tortonese 1956, Bini 1967, Bauchot 1987, Stehmann and Burkel 1984, Notarbartolo di Sciara and Bianchi 1998, Serena 2005). It is common at sizes of 30-40 cm TL (Bauchot 1987). Like other skates, this species is egg laying. Reproduction takes place in winter and 20-62 egg cases (depending on size) are laid per year (Bauchot 1987, Stehmann and Burkel 1984, Serena 2005). The egg-cases measure 46 by 35 mm excluding horns (Stehmann and Burkel 1984, Serena 2005).

threats:
The species is caught as bycatch in demersal trawl fisheries but is also fished with gillnets, longlines and handlines in artisanal fisheries (Bauchot 1987). There is a high level of exploitation over the continental shelf and upper slope, up to a depth of 800 m in the Mediterranean Sea (Massuti and Moranta 2003). Benthic trawl effort has increased both numerically and in technological terms in the shelf and slope area of the Mediterranean Sea over the past 50 years, even though a small decline occurred in recent years. For example, the Gulf of Lions area resources were initially exploited by small-scale benthic trawl fisheries comprising 27 small low powered boats (total nominal horse power of 2,700 hp), more recently effort has increased to a total nominal horse power of 19,940 hp (1974-1987) (Aldebert 1997). It is known to be retained and marketed along the African coasts of the Mediterranean Sea, where both trawl and artisanal fisheries operate (Bauchot 1987). This species is rarely landed separately from other rays in Italian Seas and it is not possible to monitor catches. An increase in CPUE and decrease in discards is reported in the central Aegean Sea (Damalas and Vassilopoulou 2011).

conservationAction:
There are no specific measures for the management or conservation of this species in the Mediterranean Sea. Landings are allowed without any minimum legal landing size nor catch limits. Fisheries regulations in the Mediterranean Sea are based on effort control (some measures of effort reduction have been implemented) and technical adjustments, such as minimum mesh size for bottom trawl, which are too small to enable escapement of even the smallest Speckled Skate individuals. Further research should be conducted on the population size and trend of the species.

useAndTrade:
The species is known to be marketed along African coasts of the Mediterranean Sea (Bauchot 1987).

redListAssessors:
Ungaro, N., Dulvy, N.K., Tinti, F., Bertozzi, M., Notarbartolo di Sciara, G., Serena, F., Abella, A. & Walls, R.H.L.


redListCategoryRationale:
Rough Skate (Raja radula) is a medium-sized species (up to 70 cm total length) that may be endemic to the Mediterranean Sea. It appears rare in the northern Mediterranean Sea but is locally abundant in the Balearic Islands and Tunisia. It occurs from coastal waters to 300 m depth, but appears to be more common at < 40 m depth in some areas, such as the Balearic Islands. Records from off Portugal and the northern coasts of Morocco require verification and may be misidentifications of other Raja species. This skate is commonly taken as bycatch of demersal trawl, gillnet, trammel net, bottom longline, and purse seine fisheries, although no species-specific catch data are available. Given that it appears to be restricted to the Mediterranean Sea where it has recently declined in certain regions, and ongoing relatively intense fishing pressure overlaps with parts of its range, Rough Skate is assessed as Endangered under Criterion A4b as a decline of >50% is estimated for the three generation period in the European region. Further investigation is required to determine this species’ full range, abundance, interaction with fisheries, and population trends.

range:
This species occurs throughout the Mediterranean Sea, but mainly in the western region and around the Balearic Islands. It is absent from the Black Sea (Serena 2005). Reports from off Portugal and the northern coasts of Morocco suggest that its range may extend into the eastern Atlantic, but these records require verification as they may be misidentifications of other Raja species. The species is found roughly at depths to 350 m.

population:
Trawl surveys have recorded this species in the Mediterranean Sea in low numbers, although it may be more common in shallow waters (< 40 m depth) that are not sampled by some surveys. The International Trawl Survey in the Mediterranean (MEDITS) programme in the northern Mediterranean Sea captured this species in 21 of 6,336 tows between 1994 and 1999 at 50–800 m depth (Baino et al. 2001). In the Gulf of Lion, trawl surveys conducted from the coast to 800 m depth in 1957–1960, 1980–1984, 1992–1995 only captured this species on the shelf and slope during the period 1980–1984 (Aldebert 1997). In surveys conducted in Italian waters, it occurred in 3.31% of 9,281 hauls performed between 1985 and 1998 at zero to 800 m depth, which were all from Sardinian and Sicilian waters (Relini et al. 2000). This skate was not caught by trawl surveys in the Adriatic Sea conducted in 1948 or 1998 (Jukic-Peladic et al. 2001).This species appears to be more common in shallow waters off the Balearic Islands (Morey et al. 2009). Ordines et al. (2011) found it in 37 of 104 bottom trawl hauls in a survey conducted at depths of 4574 m in this area. MIGJORN and MEDITS surveys performed around the Balearic Islands at depths of 36755 m in subsequent years (20012009) caught this species in 12% of 647 hauls (343 specimens) all at depths of 36–172 m (Gouraguine et al. 2011).In the western Mediterranean Sea, this species was not recorded in 131 hauls during trawl surveys from 1996–2001 at depths of 40–1,800 m (Massutí and Moranta 2003). This species seems to be uncommon in the Levantine basin, as reported by Golani (2006) and Keskin and Karakulak (2006), who listed it as rare off Israel and north Aegean Sea coasts, respectively. This species was not caught in 170 hauls off Algeria at depths of 45779 m (Echwikhi et al. 2012). In the Aegean Sea, a decline of 58% for the 1995-2000 and 2003-2006 periods was estimated, with an inferred decline of 79% for 2007-2015 and a projected decline of 89% into the future for the period 2016-2023, covering the three-generation period (27 years). However, it is unknown whether this trend is representative of the wider Mediterranean distribution, and the decline of Rough Ray in European waters is therefore estimated to be of >50% over 27 years.

habitat:
This skate is found in coastal waters at depths of ~350 m (Stehmann and Bürkel 1984, Serena 2005). Around the Balearic Islands it is relatively common at < 40 m depth.Like all skates, this is an egg-laying species. Egg cases are 5.1–5.7 cm long and are laid throughout the year (Kadri et al. 2013), though mainly in spring and summer. Embryos develop in about four months (Stehman and Bürkel 1984, Serena 2005). Females mature at 34 cm disc width (DW) and males at 30 cm DW in the Mediterranean Sea (Fischer et al. 1987, Serena et al. 2010). Maximum body size is ~70 cm total length (TL) (Fischer et al. 1987, Serena et al. 2010). Most captured specimens off the Balearic Islands measure about 30–50 cm TL (Morey et al. 2009). From the Gabès Gulf, length at maturity is reportedly 47.05 cm TL for males and 56.48 cm TL for females (Kadri et al. 2013). The age at 50% maturity was estimated to be 4.47 and 5.89 years for males and females, respectively. Maximum age and length were 12 years and 80 cm TL for females, and nine years and 65 cm TL for males. The generation length of this species is estimated to be about nine years.

threats:
This species is taken as bycatch of demersal trawl, gillnet, trammel net, bottom longline and purse seine fisheries. There is a high level of exploitation over the continental shelf and upper slope in the Mediterranean Sea (Aldebert 1997, Massutí and Moranta 2003). In some areas such as the Balearic Islands, this species is more common in shallow waters, where it is taken in trammel net fisheries targeting Cuttlefish (Sepia officinalis) and teleosts (bony fish), gillnet fisheries targeting Lobster (Palinurus elephas) and Red Mullet (Mullus surmuletus), and bottom longline fisheries targeting Grouper (Epinephelusspp.) and Sparidae (Morey et al. 2006). Trawl fisheries targeting Red Mullet, Picarel (Spicara smaris) and Small Hake (Merluccius merluccius) on the upper shelf also overlap with parts of its range. In Tunisian waters (mainly in the Gulf of Gabès), this species is taken as bycatch by trawlers at depths of 20−50 m and by gillnets at depths of < 20 m (Echwikhi et al. 2012, Kadri et al. 2013). Females outnumbered males in sampled catches in gillnets; 80% of the females and 57% of the males were mature (Echwikhi et al. 2012).In a multigear small-scale fishery (trammel net, gillnet and bottom longline, mainly), this species made up 12% in abundance of the elasmobranch capture at four to 160 m depth between 1998 and 2008 (Mallol et al. 2009). Trammel nets are the most likely to catch this species (Morey et al. 2006, 2009).Species-specific data are commonly not available because landings of skates are grouped as “rays” or “skates”. Despite this, a monitoring program conducted at the Palma de Mallorca landing site showed that this species was the sixth most marketed elasmobranch on the island, at an estimated biomass of 6.3 tonnes in 2009. With 66.5% of this biomass coming from bottom trawlers and only 33.5% coming from small-scale fisheries (Morey and Navarro 2010); commercial fisheries are a more significant threat.

conservationAction:
No species-specific management or conservation measures are in place in the Mediterranean Sea. If this species occurs in Portuguese waters (International Council for the Exploration of the Sea sub-area IX), a Total Allowable Catch (TAC) measure is in place for all skate and ray species. In 2013, the TAC was 3,800 tonnes for this sub-area and the Bay of Biscay (sub-area VIII) combined (regulations are available online at http://faolex.fao.org).Research is required to determine this species’ full range, abundance, interaction with fisheries, and population trends.


redListCategoryRationale:
European regional assessment: Near Threatened (NT) Undulate Skate (Raja undulata) is a medium-sized (up to 114 cm total length), inshore skate or ray that has a very fragmented distribution in the northeast Atlantic Ocean, with a small number of discrete areas (stocks) where it may be locally common (e.g., southwest Ireland, the English Channel, and southern Portugal). It also occurs very sporadically in the Mediterranean Sea, where it appears to be uncommon. No reproducing populations are known in the Mediterranean, however they may be present. It occurs in shelf waters down to about 200 m depth, although much more commonly found in coastal waters <50 m deep. This is a medium-bodied skate and therefore considered of higher value in fisheries. The species is taken as retained bycatch by trawl, trammel net and other demersal fisheries. In 2009, regulations were introduced in European Atlantic waters that stipulated that bycatch had to be returned alive; these regulations have recently been amended to allow limited take (20 kg quota per trip) in the English Channel and the Bay of Biscay, although retained in Portuguese waters and in SW Ireland. Its fragmented distribution means that some populations are widely separated, possibly with little exchange between adjacent stocks. In some areas where it was locally common, data suggest declines, but some of these areas are at the fringes of its geographic range and time series of catches show considerable interannual variability. The stock off southwest Ireland appears to be the most isolated and, whilst commercial and recreational landings have decreased, it is suspected to be a bycatch in tangle net fisheries targeting commercially important crustaceans. This medium-bodied skate has limiting life-history characteristics that make it more vulnerable to exploitation than smaller skate species (three generation period of about 45 years). Given the fragmented distribution of this inshore species, we suspect the core habitat to be less than 20,000 km2, with discrete stocks occurring in ≤10 locations. Given that Undulate Skate inhabits outer estuaries and inshore habitats, and these habitats are subject to multiple anthropogenic stressors, it is suspected that these important habits are declining in both quality and extent. It has not been possible to calculate the Area of Occupancy (AOO) of the species as records from all data sources, including commercial and recreational angler sources, have not been compiled. However, the AOO is suspected to be restricted and may approach the 2,000 km2 threshold for listing under criteria B (restricted geographic range), and Undulate Skate is therefore assessed as Near Threatened. It should be noted that due to the fragmented nature of this species’ distribution and consequent localised abundances, the population is no longer thought to be undergoing as great a decline as initially thought in the earlier 2009 global Red List assessment (Coelho et al. 2009). The acquisition of this new information allows a non-genuine down-listing of the species from Endangered (global assessment) to Near Threatened (this European regional assessment). However, the level of genetic interchange between these potentially discrete, fragmented stocks is unknown; therefore, careful monitoring of this skate across its stock range is required to determine accurate population trends of mature individuals. Catch and bycatch controls should remain in place until further stock-specific population size and trend data are available. Furthermore, the species’ slow life history and patchy distribution create concern over the resultant uncertain stock status.

range:
This species has a fragmented distribution in the eastern Atlantic Ocean and in the Mediterranean Sea, with discrete areas (stocks) where it may be locally common (southwest Ireland, eastern English Channel, southern Portugal). It is patchily distributed in the northeast Atlantic from the British Isles to northwest Africa. The southwest coast of Ireland, the Bristol Channel, the English Channel, and southwestern North Sea are the northern-most limits of its geographic range (Ellis et al. 2012). In the European region the fish is very much restricted to the following areas (Ellis et al. 2012);SW Ireland (small series of bays)English ChannelCoastal waters of Bay of BiscayCertain lagoons along the Cantabrian coastGalician ríasWestern PortugalSouthern Portugal to Gulf of CadizSouthwest of Ireland, this skate occurs off Doonbeg, Tralee Bay, Brandon Bay, off Ballydavid, Dingle Bay and off Mizen Head. Within the English Channel, it is most frequently encountered around the Channel Islands and the adjacent Normano-Breton Gulf and the eastern English Channel from Lyme Bay to Beachy Head and the Isle of Wight. In the Bay of Biscay region, it is caught outside the Gironde Estuary, northwards to La Rochelle, and further north from Concarneau to south of Nantes, including outside the Loire Estuary. Around the Iberian Peninsula, it occurs near the Tagus and Sado estuaries and in the Portuguese bays Setúbal and Sesimbra, and has also been found along the Algarve coast, including at Lagos and Ría Faro-Olhao, and in Galician waters, including in and outside the Ría de Muros e Noia, Ría de Arousa and Ría de Pontevedra. This skate may be locally abundant here in parts, and is one of the main species taken in artisanal fisheries in these inshore areas. In southern Spain, it is found in the Bahía de Cádiz (Ellis et al. 2012). Within the Mediterranean Sea, this skate is found mainly in the western basin, including waters off southern France and the Tyrrhenian Sea, and has been recorded from the eastern basin from the Adriatic Sea to Israeli waters (Serena 2005, Capapé et al. 2006, Psomadakis et al. 2006). However, bottom trawl surveys carried out in the Adriatic Sea since 1948 have not encountered any Undulate Skate specimens since 1983 (Ferretti et al. 2013). Most records of this species in Mediterranean waters are sporadic and refer to individual fish caught in various locations. Whilst a persistent, breeding population in the Mediterranean Sea has not been reported, it is possible. Undulate skate is often reported near sites of freshwater input and lagoons, and so the southern coast of France may provide suitable habitat for this species, which has been confirmed from Sète and the Languedoc coast (Ellis et al. 2012). Outside the European region, the fish also occurs off the Atlantic coast of northwestern Africa (Morocco).

population:
There appears to be a discrete subpopulation in Tralee Bay, Ireland, from where angling records indicate a peak in catch in 1981-1982, with low but stable catches since then (ICES 2007). This skate has traditionally been observed in English beam trawl surveys in the eastern English Channel, but was absent during 2006 and 2007, subsequently returning to levels seen prior to 2006 from 2008 onwards (ICES 2008, 2012). It is locally common in parts of the Bay of Biscay (ICES 2007), but common off southern Portugal (Coelho and Erzini 2006), where it may form a separate population to that on the Portuguese west coast (Moura et al. 2007). It appears to be uncommon in the Mediterranean Sea, with only occasional records (Baino et al. 2001, Bertozzi et al. 2003). Determining accurate stock trends in surveys is problematic due to the fragmented distribution of the species, and some survey methods are not appropriate for this species. Where there are suitable inshore research trawl surveys, data indicate that this skate is generally rare across most of its range, but can be locally common. Catch per unit effort (CPUE) has ranged between one and eight individuals per year in the French Channel Groundfish Survey in the eastern English Channel in waters 13–82 m deep between 1993 and 2010 (Martin et al. 2010). The population trend was stable but highly variable, with no specimens caught in 1993 (Martin et al. 2010). For the years that this species was caught, the mean CPUE ranged from about 0.03–0.12 individuals per hour. Reported commercial landings in the Celtic Sea, western English Channel, southern North Sea and eastern English Channel by the English fleet decreased from 2007 to 2010, in line with the introduction of management measures in 2009. The French Evaluation des resources Halieutiques de l’Ouest Europe (EVHOE) survey in the Bay of Biscay (1997–2010) had six records of the species, with single specimens recorded in 1997 and 2007 and two specimens each in 2000 and 2009 (Ellis et al. 2012). The French beam-trawl survey of the Bay of Biscay, which has been ongoing since 2007, caught three to five individuals each year. Between 1992 and 2010 this species was rarely encountered (36 individuals in total) in surveys around the north coast of Spain in the Cantabrian Sea and off Galicia, and the Gulf of Cádiz, where 15 individuals were found in coastal areas just outside the Bahia de Cádiz (Ellis et al. 2012). However, it is potentially more locally abundant in Portugal where it was amongst the principal elasmobranch species caught in the trammel net fishery off the Algarve (Erzini et al. 2002). Commercial trammel net vessels in Portuguese bays near Setúbal and Sesimbra were sampled between October 2004 and August 2005, from which it was the predominant elasmobranch species in terms of catch weight (Baeta et al. 2010). In summary, this skate has an extremely fragmented distributed and is rarely encountered in many areas, although it can be locally common in specific areas and seasons. Historical accounts from the 1800s, however, do not indicate that the species was more wide ranging in the past (Ellis et al. 2012). There are few suitable research surveys in shallow coastal waters, and those available give low and variable indices over time (e.g., beam trawl surveys in the English Channel). Prior to the 2009 prohibition in landings, species-specific landings data were indicating a decline. It should be noted that due to the fragmented nature of this species’ distribution and consequent localised abundances, the population is no longer thought to be undergoing as great a decline as initially thought in the earlier 2009 global Red List assessment (Coelho et al. 2009).

habitat:
This skate occurs in shelf waters to about 200 m depth, and appears to be more common in shallow waters, particularly less than 50 m deep (Stehmann and Bürkel 1984, Serena 2005, Coelho and Erzini 2006, Baeta et al. 2010). Smaller specimens have been reported in coastal lagoons, rías, and outside estuaries, which suggests that it may use these sheltered habitats as nursery areas (Coelho et al. 2002). The geographic range is not continuous, with isolated patches of presence due to strict habitat preferences. They seem to associate with coarse sediments possibly associated with biogenic habitats, which restricts the extent of their core habitat. We suspect the core habitat to be less than 20,000 km2, with ≤ 10 broad locations (from north to south including: southwest Ireland, central English Channel, Bay of Biscay, Cantabrian Shelf, Galicia, western central Portugal, Algarve, and an uncertain range within the Mediterranean Sea) with site-specific positions within these regions (see ‘Geographic Range’ text). Habitat quality is suspected to have declined in the species inshore and estuarine habitats as a result of impacts from a range of sources, including, contamination (urban and industrial pollution), shipping, dredging navigation channels, aquaculture, other habitat modification. Like other skates, reproduction is oviparous. Maximum size is at least 114 cm total length (TL; Ellis et al. 2012). Significant regional differences have been observed in size at first maturity of this species. In Portugal, length at 50% maturity (L50) for females is 76.2 cm TL in the Algarve (southern) region and 83.8 cm TL in the Peniche (western) region, while L50 for males is 73.6 cm TL in the Algarve and 78.1 cm TL in Peniche. In the English Channel male L50 is 82 cm TL (McCully et al. 2012). Age at first maturity for the Algarve population has been estimated to occur at 8.98 years in females and 7.66 years in males (Coelho and Erzini 2006). An annual reproductive cycle has been observed, but differences occur between the different populations; in Portuguese waters this species breeds mainly during late spring and early summer, with some spawning in December (Coelho and Erzini 2006, Moura et al. 2007). These differences seem to be related to water temperature, with reproduction restricted to periods of cooler water. The maximum observed age for this species is 13 years old (Coelho and Erzini 2002) but longevity has been estimated at 21-23 years (Coelho et al. 2002). The population off the south Portuguese coast has a very slow growth rate (k=0.11; Coelho and Erzini 2002). Natural mortality for this population has been estimated at 0.20-0.219 per year (Coelho et al. 2002). It is unclear as to how much genetic interchange there is between what could be a succession of discrete stocks (Ellis et al. 2012). Generation period for this species varies from 14.9-15.9 years in females and from 14.3-15.3 in males.

threats:
This species is a bycatch of beam and otter trawl, trammel net and other demersal fisheries operating within its range. It has a fragmented distribution and declines have been documented in some areas where it was formerly considered locally abundant. For example, the stock off southwest Ireland appears to be the most isolated and, whilst commercial and recreational landings have decreased, it is suspected to be a bycatch in tangle net fisheries targeting commercially important crustaceans. Catch records are available from two charter-angling vessels in Tralee Bay (southwest Ireland), where this species forms a discrete population (ICES 2007). These data show that catches declined from a high of 80-100 fish per year in 1981 to 20-30 fish per year in the mid-1990s (60-70%), before increasing to 40-60 per year in 2001-2003. Catches appeared to decline again, with less than 20 fish recorded in 2005, although they fluctuate each year (ICES 2007). ICES advice has been for no target fishing in the North Sea, English Channel and Celtic Seas, with measures taken to minimize bycatch (ICES 2012). This skate is captured in large quantities as bycatch in the mixed species trammel net fishery that operates off the southern coast of Portugal (Coelho et al. 2002). It was traditionally retained and marketed for human consumption. It is captured mainly in shallow waters, with CPUE values in this fishery decreasing from 1.91 specimens per 1,000 m net at 10-30 m depth to 0.03 specimens per 1,000 m net at more than 90 m depth (Coelho et al. 2005). Portuguese official fisheries statistics for landings of Raja spp. in the Algarve decreased by 29.1% between 1988 and 2004 (DGPA 2001). This is the most common skate species in this area and its size makes it more vulnerable to depletion than smaller sympatric skate species; these declines may mask changes in the species composition (Erzini et al. 2001, Coelho et al. 2005). The species is also a known bycatch of the Spanish demersal trawl fleet operating in the Cantabrian Sea, southern Bay of Biscay, which targets a mixture of gadoids and flatfish over the continental shelf (ICES 2007). Species-specific French landings data for the Celtic Seas report 12 tonnes (t) in 1995, six tonnes in 1996, and ten tonnes in 1997, after which landings fell to two tonnes in 1998, 1one tonne in 1999, to zero tonnes in 2000-2001, and have remained low at 0-3 tonnes per year since (ICES 2007, 2014). However, fisheries in the Normano-Breton Gulf may have reported landings using generic skate landings categories. This species’ preference for shallow waters places it within the range of intensive artisanal coastal fisheries operating along the western coast of Africa (Walker et al. 2005). Although no specific details are currently available on catches, this species is presumably a used bycatch of these, and demersal trawl fisheries operating in this area. Exploitation of the continental shelf is also high in the Mediterranean Sea (Massuti and Moranta 2003). Like many other larger skates, this species possesses life history characteristics that may increase vulnerability to exploitation, reduce rate of recovery and increase the risk of extinction: including delayed age at maturity, long generation time (14-15 years), low fecundity, and consequently slow population growth (Dulvy et al. 2000). Coupled with their fragmented distribution and coastal nature, this species is particularly sensitive to exploitation, so catch and landings need close monitoring. Historically, there has been some confusion between Undulate Skate and Small-eyed Skate (R. microocellata), both being referred to as ‘painted ray’ in some areas (Ellis et al. 2012), which could compromise the quality of some historical information. The site preferences of this species (shallow water, often lower salinity inshore bays and estuaries, and course ground) put this skate at higher potential risk of habitat decline or degradation than many other skate species. Declines are already suspected in both extent and quality of these habitats due to shipping, dredging, pollution, aquaculture, and possibly, aggregate extraction.

conservationAction:
In Ireland, Tralee Bay is voluntarily closed to commercial fishing to protect regionally important elasmobranchs such as Undulate Skate and Angelshark (Squatina squatina), which are only found in localised populations on the Irish west coast (ICES 2007). Recreational fishing continues in this area. The most recent ICES advice (ICES 2014) is for no target fishing in the North Sea, English Channel and Celtic Seas, and for measures to be taken to minimize bycatch and bycatch mortality. Species-specific monitoring of catches and landings is required to determine the proportion of Undulate Skate taken. Due to the consequent localised abundances and absences of this patchily distributed species hindering accurate population size estimations, target fisheries for Undulate Skate were prohibited within European Union (EU) waters (ICES 2012). The EU’s Total Allowable Catch (TAC) and quota regulations listed this skate as a prohibited species in 2010, specifying that ‘it shall be prohibited for EU vessels to fish for, to retain on board, to tranship or to land Undulate Skate in EU waters west of Scotland and Ireland, the Celtic Seas, the English Channel, the Bay of Biscay, Iberian waters and Madeira’ (CEC 2011). The regulations also stated that ‘Undulate Skate shall be promptly released unharmed to the extent practicable’. Most recent fishery regulations allow for some limited landings of Undulate Skate from the Bay of Biscay and English Channel (CEC 2015). Given the high inter-annual variability in fisheries trawl surveys, the lack of species-specific landings data since 2009 and some declining landings trends prior to this time, better monitoring is required to determine population trends of mature individuals which can support assessments. Furthermore studies to determine the level of genetic interchange between these potentially discrete, patchy stocks would assist future assessments.

useAndTrade:
Flesh marketed for human consumption. In Portugal, larger specimens can reach relatively high market prices (R. Coelho pers. obs. 2014). This skate is not targeted (it occurs at too low population densities), however it is utilized when taken unless catch/bycatch controls are in place. The fish is also caught in recreational fisheries.

redListAssessors:
Ellis, J.R., McCully, S. & Walls, R.H.L.


redListCategoryRationale:
European regional assessment: Least ConcernDeepwater Skate (Rajella bathyphila) occurs on deeper continental slopes and probably abyssal plains in the Northeast Atlantic, mainly at depths of greater than 1,400 m. It is occasionally landed as fisheries bycatch, but its deepwater range places the majority of the population outside the range of current fishing pressure. In the absence of potential threats, Deepwater Skate is assessed as Least Concern in the European region. If deepwater fisheries expand to greater depths within this species’ range in future, this assessment should be revisited. Monitoring of catches is important given that life history characteristics common to most deepwater skates make them vulnerable to rapid depletion when heavily fished.

range:
The species is found in the North Atlantic from west to east. In the Northeast Atlantic, this species occurs in the Strait of Denmark, southwest of Iceland, including Reykjanes Ridge, Rockall Trough, in the northern region of the Bay of Biscay and south to areas off Rio de Oro in Western Sahara (Ebert and Stehmann 2013). It also occurs around Greenland (Nakaya 1995) and on the Mid-Atlantic Ridge (Stehmann 1978, Stehmann 1995). The depth range is 600-2,300 m but is mainly found at depths greater than 1,400 m.

population:
Little is known about population size or structure, but it is apparently rare at sampled depths. This species is mainly known from sporadic records from local deepwater fisheries, as it is rarely encountered by deepwater research trawl surveys (Ebert and Stehmann 2013).

habitat:
This skate is found on deeper continental slopes and probably abyssal plains at depths of 600−2,300 m, but mainly greater than 1,400 m, within a temperature range of 2.5−4.0 °C (Stehmann and Bürkel 1984, Ebert and Stehmann 2013).The reproductive biology of this species is largely unknown. Like other skates, it is an egg-laying species with yolk-only nutrition. Females produce ~40 egg capsules per year. The young hatch after several months of embryonic development, although timing may vary with water temperature (i.e., slower development is likely in colder waters; Gordon and Duncan 1989). Size at birth is 11.5 cm total length (TL) (Stehmann 1978). Adults reach sexual maturity at ~65 cm TL in both males and females. The maximum recorded size is 93 cm TL (Stehmann 1978).

threats:
This species is occasionally caught as bycatch in local commercial deepwater bottom trawl fisheries at depths greater than 1,000 m, for example, from the Rockall Trough in the Northeast Atlantic (Ebert and Stehmann 2013). Only larger specimens are kept and landed (e.g., in France smaller individuals are discarded). The presumed wide distribution mainly at lower slope depths likely protects the species from exploitation.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX), and have also been gradually reduced since then.The harvesting trends of the species should be monitored.


taxonomicNotes:
This species is difficult to distinguish from the deepwater skate (Rajella bathyphila) and these two species may be sympatric. It has also been misidentified as Rajella fyllae before.

redListCategoryRationale:
European regional assessment: Least ConcernBigelow’s Skate (Rajella bigelowi) is a little known, small (up to 53 cm total length) bathydemersal skate, recorded at depths from 367 m to 4,156 m, but most records exceed 1,000 m. Sporadic records from various parts of the North and Central Atlantic indicate that this species is widespread, and possibly much wider than records currently indicate. This suggests that the majority of the population likely lies outside the range of current deepwater fisheries. Given the limited overlap between its range and current fishing operations, and lack of data to suggest declines in abundance, Bigelow’s Skate is assessed as Least Concern in European waters. This assessment should be revisited if deepwater fisheries expand to greater depths within its range. Monitoring of catches will be important given that deepwater skates generally have life-history characteristics that can make them vulnerable to rapid depletion when heavily fished.

range:
This species is widely distributed in the North Atlantic. In the Northeast and Eastern Central Atlantic, there have been sporadic records between 65°N and 10°N, from Greenland (Nakaya 1995), Iceland (Jónsson and Pálsson 2006), Rockall Trough, Porcupine Seabight, western Bay of Biscay, north of Morocco, the Azores, and off Rio del Oro in Western Sahara and Guinea, including the Mid-Atlantic Ridge (Orlov et al. 2006). The depth range is 3674,156 m (mostly greater than 1,000 m).

population:
Little is known about the population size or the species’ abundance, but it is apparently rare at sampled depths.

habitat:
This bathydemersal skate occurs on continental slopes, abyssal plains and deepwater rises at depths of 3674,156 m (mostly greater than 1,000 m).  An unpublished record by the British RV ‘Challenger’ from the outer Porcupine Seabight at 4,156 m depth appears to be the deepest known record of the species. The mean depth of existing records is 1,669 m. Most of its range falls within a temperature range of 2.54.0°C.Little is known about this species’ life history (Ebert and Stehmann 2013). Like other skates, it is an egg-laying species and embryos derive nutrition only from the yolk. Size at birth is estimated at < 8.9 cm total length (TL; Stehmann 1995). The maximum recorded size for this species is 53 cm TL (Orlov et al. 2006). 

threats:
This skate is occasionally taken as bycatch in deepwater bottom trawl fisheries at depths of greater than 1,400 m, but it is usually discarded because of its small size and thorniness (Ebert and Stehmann 2013). Much of the range of this species occurs well beyond depths currently fished, most likely offering it significant refuge from fishing pressure. The presumably wide distribution in mainly lower slope depths has thus far protected the species from targeted exploitation.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays (Rajidae) of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea and North Sea (International Council for the Exploration of the Sea [ICES] Division IIa and Subarea IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 825% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999-2014), the TAC was higher than reported landings and therefore not effectively constraining catches.Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES Subareas VIIX) and have also been gradually reduced since then.

redListContributors:
Orlov, A., Kulka, D.W., Barker, A.S., Stehmann, M.F.W. & Fordham, S.


taxonomicNotes:
Breviraja marklei McEachran & Miyake, 1987 is a synonym of Rajella fyllae (J. McEachran pers. comm. 2008).

redListCategoryRationale:
European regional assessment: Least Concern (LC)Round Skate (Rajella fyllae) is widely distributed in the deeper shelf and upper slope waters of the north Atlantic, at depths of 170–2,050 m. This is a small-bodied species that may have moderate to high population growth rates and thus be fairly resilient to low levels of exploitation. It is taken as bycatch by trawl and longline fisheries operating in the north Atlantic, and is discarded. Its wide depth range offers refuge beyond the deepest reach of trawl fisheries. Available data on trends in abundance suggest that the population is relatively stable at present, but these data are for a limited period only, and longer-term trends are not known. There has not been any indication of a decline in abundance or range, and so it is inferred to be of Least Concern. Given that fisheries are known to operate at depths at which the species is most abundant, bycatch levels should be monitored.

range:
In the Northeast Atlantic, Round Skate (Rajella fyllae) is found from the southeastern part of the Barents Sea (Kanin Peninsula) to southern Norway, southern Greenland, Iceland, Faeroe Islands to Shetlands, and the western coasts of British Isles and the Bay of Biscay (Stehmann and Bürkel 1984, Dolgov et al. 2005). Its depth range is 170-2,050 m.

population:
Annual mean catch rates in scientific trawl surveys are in the range of 0.02–0.03 fish per hour with maximum catch rates of five fish per hour (Dolgov et al. 2005). Abundance in this area appears relatively stable in recent years. In Norwegian waters this species is abundant along northern coasts (Williams et al. 2008) and also in the Skagerrak and off southwestern Norway. During a scientific trawl survey in Norwegian waters between 1984 and 1987, this skate occurred in 107 of the 639 trawls and with a concentration of catches off southern and southwest Norway and at depths > 240 m (Skjæraasen and Bergstad 2001). Owing to the lack of evidence for population decline, population stability is inferred.

habitat:
This skate is bathydemersal, occurring in deeper shelf and slope waters between 170 and 2,050 m. Average depth of capture is about 400–800 m in the Northeast Atlantic. In the Barents Sea, this skate was observed to prefer waters of 2-7°C (Dolgov et al. 2005).Very little is known of its biology. Maximum recorded size in the Barents Sea is 57 cm total length (TL, Dolgov et al. 2005). Size at birth is estimated at 7-11 cm TL. This is an egg laying species; due to its cold water habitat, embryonic development may take several months. 

threats:
Presently, there are no directed fisheries for this species. It is captured incidentally in deepwater fisheries that operate within its range. For example, it is one of three dominant skate species taken as bycatch in trawl and longline fisheries operating at depths of 800 m in the Barents Sea (Dolgov et al. 2005). It is usually discarded due to its small size and thorniness (Ebert and Stehmann 2013).Although fisheries operate in parts of its range, the species’ wide depth range offers it refuge beyond the reach of most trawl fisheries. Furthermore, deepwater effort in the Northeast Atlantic is regulated by quota and is presently much lower than it was during the 1960s and 1990s, having decreased in effort gradually over the past decade (Dransfeld et al. 2013, STECF 2014). These fisheries should still be monitored in case of future expansion, which could pose a threat to this skate.

conservationAction:
There are no species-specific regulations related to this species. In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches.  Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then. In 2013, the TAC for all skate and ray species grouped was 21,800 tonnes (regulations are available online at http://faolex.fao.org). Further research should be conducted on the population size and trend of the species.

redListAssessors:
Kulka, D.W., Barker, A.S., Orlov, A., Pasolini, P., Ellis, J.R., Dolgov, A. & Walls, R.


redListCategoryRationale:
Mid-Atlantic Skate (Rajella kukujevi) is a poorly known, deepwater species endemic to the Northeast Atlantic. It is found at depths of 775–1,500 m and is most common below 1,000 m. Relatively few individuals have been captured since it was originally described and very little data are available. Little is known of the species’ biology, though it is likely to have inherent limiting life history characteristics similar to other deepwater skates, making it potentially vulnerable to exploitation. It is rarely taken as bycatch by deepwater trawl fisheries targeting deepwater teleost fishes. This species’ deep depth range may afford it refuge from fishing pressure in some areas, though some fisheries operate throughout the shallow end of its bathymetric range. Mid-Atlantic Skate is assessed as Least Concern because of the suspected minimal overlap between its range and deepwater fisheries operations. Efforts should be made to assess catch and population trends, and this assessment should be revisited as soon as data are available.

range:
Mid-Atlantic Skate (Rajella kukujevi) is endemic to the Northeast Atlantic. It is found from the Mid-Atlantic Ridge to Iceland, Ireland and the Faeroe's Exclusive Economic Zone (EEZ), west of Scotland and Ireland, with one record south to the Bay of Biscay (Rodríguez-Cabello et al. 2012). It is most frequently caught off the Rockall Trough, Bill-Baileys, Lausy and Hatton banks and southwestern corner of Faroes EEZ (Dolganov 1985, Clarke 2000, ICES 2006).The depth range is 775–1,500 m.

population:
Nothing is known about the population size, but the trend is suspected to be stable owing to the minimal range overlap with deepwater fisheries.

habitat:
This bathydemersal species is found at depths of 775–1,500 m, with the majority of individuals captured at depths below 1,000 m (ICES 2006). The average depth of all known records is 1,179 m. This species is presumably egg laying like other skates, but nothing else is known of its reproductive biology. It reaches a maximum body size of at least 83 cm total length (TL; Dolganov 1985). Iglésias (2012) reported a maximum size of 79–84 cm TL for mature males, while Rodriguez-Caballo (2012) reported maximum sizes of 56.8 and 72.9 cm TL for males and females, respectively.

threats:
This species is taken as bycatch in deepwater mixed bottom trawl and longline fisheries, particularly in the Rockall Trough area by French vessels that occasionally land large specimens (Ebert and Stehmann 2013). Owing to the Total Allowable Catch (TAC) measures introduced in 2009 (see ‘Conservation Actions’ section), reported landings of most deepwater species in 2012 were very low or zero. As most species are taken as bycatch in mixed fisheries, it is likely that discarding has increased (ICES 2013).It is unlikely that deepwater fisheries in the Northeast Atlantic will be expanding in the foreseeable future, but there is still some overlap between the shallowest extent of this species’ range and deepwater fisheries operating in the region. It is therefore important to monitor the reach of deepwater fisheries because, like other deepwater skate species, this species is suspected to have a slow life history, making it particularly vulnerable to exploitation.

conservationAction:
Skate and ray TACs were established for European Union waters in 2009, including this species’ range from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES Subareas VI-IX). The TACs have been gradually reduced each year since 2009 to 21,800 tonnes in 2013 for all skate and ray species grouped (regulations are available online at http://faolex.fao.org). Further research is required on the population size, trends, harvest and use of the species, while any catches should be recorded and monitored. 


redListCategoryRationale:
European regional assessment: Least ConcernSailray (Rajella lintea) is a deepwater skate known from sporadic, deepwater records from the Northeast Atlantic at depths of 196–635 m. Potential overlap with fishing effort is greater in the Northeast Atlantic than other parts of the Atlantic, but catches are rare. Given the limited interaction between this species and fisheries, it is inferred that the majority of its range falls outside the reach of deepwater fisheries operating in this region, and therefore Sailray is assessed as Least Concern in European waters. Monitoring of population trends and capture in fisheries should be implemented.

range:
This deepwater skate is widely distributed in the Northwest Atlantic, but in the Northeast Atlantic it is only known sporadically from southern Iceland, north of the Faroes and Shetland Islands, the Skagerrak, Barents Sea and Spitsbergen (Stehmann and Bürkel 1984, Dolgov and Igashov 2001). In the Barents Sea, single specimens have been recorded in trawl and longline catches, mainly in areas influenced by warm Atlantic waters, including the Sørøya Bank, Fugløya Bank and Kopytov area (Dolgov et al. 2005b).

population:
In the Barents Sea, this skate regularly occurs in research surveys, but in very low, consistent numbers (Dolgov et al. 2005a).

habitat:
This skate occurs at shallower depths in the Northeast Atlantic (196–635 m) than in the Northwest Atlantic (316–1,455 m, the deepest where it has been fished; ICES 2006).  Like other skates, it is an egg-laying species that produces egg capsules 10.7 cm long and 7.7 cm wide and deposits them on sandy or muddy flats (Breder and Rosen 1966, Funicelli 1972). The maximum body size recorded for this species was a mature male at 125 cm total length (Ebert and Stehmann 2013).

threats:
The main threat to Sailray (Rajella lintea) is fishing. Catches are sporadically reported in the Northeast Atlantic. It is only occasionally taken as bycatch in trawl and longline fisheries targeting Atlantic Cod (Gadus morhua), Haddock (Melanogrammus aeglefinus) and Blue Catfish (Ictalurus furcatus) above 300 m depth, and Greenland Halibut (Reinhardtius hippoglossoides) below 300 m in the Barents Sea (Dolgov et al. 2005b). This skate is also taken by trawl fisheries in the Norwegian Deep and the Skagerrak (Skjæraasen and Bergstad 2001), and elsewhere in the Northeast Atlantic. It is usually discarded, but larger individuals are sometimes retained. Given how infrequently catches are reported, it is suspected that the majority of this species’ depth range is below the reach of most deepwater fishing fleets (Ebert and Stehmann 2013).This species was thought to be less common in Swedish waters, but reports are now increasing from sports fishermen and commercial fisheries. It appears that logbooks started reporting landings of Sailray around the time Sweden banned landings of Blue Skate (Dipturus batis), in December 2004. These landings need to be further investigated to establish if these specimens are in fact Sailray, and not Blue Skate.

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea (International Council for the Exploration of the Sea [ICES] Division IIa) and North Sea (ICES sub-area IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX). These TACs have also been gradually reduced since then (regulations available online at http://faolex.fao.org). Any catches of the species should be recorded and monitored. 

redListAssessors:
Ellis, J., Dolgov, A., Walls, R. & Dulvy, N.

redListContributors:
Fordham, S., Kulka, D.W., Orlov, A. & Stenberg, C.


redListCategoryRationale:
European regional assessment: Critically Endangered (CR) The large size (up to 200 cm total length) of White Skate (Rostroraja alba) renders it particularly catchable by various fishing gear, which in combination with its late age at maturity and long inferred generation time (25-30 years) makes this species vulnerable to fisheries exploitation. It is likely to be caught as bycatch in multi-species trawl fisheries which operate on much of the continental shelf and slope habitat. This skate has undergone significant declines in abundance and substantial reductions in geographic range within the Mediterranean Sea and the Northeast Atlantic. The subpopulation in the Northeast Atlantic represents the bulk of its range within European waters and data from this sub-region are more accurate than elsewhere. The species is considered to be locally near-extinct from the Celtic Sea, Irish Sea, English Channel, and around Ireland. It is suspected to be locally near-extinct from the Bay of Biscay and Atlantic Iberian waters, and is very rarely encountered in the Azores and mid-Atlantic ridge region. There is limited restriction of fishing effort on this species.  Within the Mediterranean Sea, available data indicate that this species formerly was captured frequently in the northwest region during the 1960s and off Tunisia and Morocco in the early- to mid-1970s. It is now considered rare and is suspected to have undergone a significant decline in both abundance and extent of occurrence (EOO). There is a continued unregulated fishing pressure in the Mediterranean Sea. The species is suspected to have declined by >80% over the past three generations (75-90 years) in European waters based on anecdotal evidence that suggests localized extinctions, therefore classifying the species as Critically Endangered under criterion A2bd.

range:
The overall geographic range of White Skate (Rostroraja alba) covers the eastern Atlantic coasts from the southwest British Isles south to South Africa, including the Mediterranean Sea, and extending into the southwest parts of the Indian Ocean (Stehman and Bürkel 1984). This species is listed as occurring in the northwest European seas (Stehman and Bürkel 1984), however few recent valid records exist in northern areas of the Northeast Atlantic, mostly from west of Ireland (ICES 2013). This species may have been vagrant in the North Sea ecoregion, but the reliability of recent data in this area has also been questioned (ICES 2012). It is considered to be locally near-extinct from the Celtic Seas ecoregion (Ellis et al. 2010) including the Irish Sea, English Channel and around Ireland. This species is thought to be locally near-extinct from the Bay of Biscay and Atlantic Iberian waters, and is very rarely encountered in the Azores and mid-Atlantic ridge region. Its depth range is 40-500 m.

population:
Few data are available on the population size of this skate. The data do indicate that it has undergone a reduction in abundance and is now considered extremely rare in the Northeast Atlantic and Mediterranean Sea. Northeast Atlantic The absence of White Skate from contemporary surveys in the Northeast Atlantic, as noted by ICES (2006), is cause for concern. There are anecdotal and historical reports suggesting that local subpopulations were targeted in fisheries in the western English Channel, Baie de Douarnenez (Brittany) and off the Isle of Man, and it is now very rarely observed in the region (Dulvy et al. 2000, Rogers and Ellis 2000, Ellis et al. 2010, ICES 2012). The species is now considered locally near-extinct throughout waters west of Britain, the Celtic Sea, and the English Channel (ICES 2012), excluding waters west of Ireland, which is the only region where it has been found in recent years (ICES 2012). Similarly, it was not encountered between 1988 and 2008 during scientific (beam and small otter) trawl surveys of the eastern English Channel in July and October, in which a total of 30,500 individuals of 16 other species of skate and small elasmobranch were captured (Martin et al. 2012). Nevertheless, it has to be taken into account that this skate could be confused with Shagreen Skate (Leucoraja fullonica), and that landings of White Skate are also reported as Blue Skate (Dipturus batis) and Sharpnose Skate (D. oxyrinchus) in French ports (Iglésias et al. 2010). White Skate has declined in the Bay of Biscay (Quero and Cendrero 1996). In Iberian waters, Portuguese fisheries land very low numbers of the species, with reported landings ranging from five tonnes in 2004 to 11 tonnes in 2009 (ICES 2012). Mediterranean Sea Historically, within the Mediterranean Sea this species was captured frequently off northern coasts of Tunisia in the mid-1970s and the coast of Morocco in the early 1970s (Capapé 1976). It was described as being more or less frequent in the northwest Mediterranean Sea (1965) and the French coast (1950 to 1960s) and Italian Seas (1972) (Capapé 1976). However, a time series of comparative trawl surveys running from 1957 to 1995 in the Gulf of Lions, in the northwest Mediterranean basin failed to catch any specimens. This consisted of eight separate surveys, conducted by four survey vessels. A total of 1,359 tows were carried out on shelf and slope areas extending from the coast to 800 m depth (which includes the known depth range of this species) (Aldebert 1997). In the eastern Mediterranean basin, this skate was captured in the Adriatic Sea (1963) and the limit of its eastern distribution was Greece (Capapé 1976). It was regularly captured by fisheries in Tunisian waters and was common in all Tunisian coastal waters, but captures were more frequent in the northern part (Capapé 1976). This species is now rare along the Tunisian coast (Bradaï 2000), but Kadri et al. (2014) reported the collection of 320 specimens in 2007 in the Gulf of Gabès, which could provide an insight into its local abundance in comparison to the overall data derived from other surveys. In the Adriatic Sea, comparative trawl surveys indicate that this skate was present in 4% of hauls of the Hvar 1948 survey (based on 138 valid hauls in depths of up to 400 m). Since then, two time series of trawl surveys have occurred in the Adriatic Sea. The Italian national trawl survey National Group for Demersal Resource Evaluation (GRUND) covered the period of 1982-2008, whereas the Mediterranean International Trawl Survey (MEDITS) programme began in 1985 and is still ongoing. White Skate was captured sporadically and infrequently in both of these surveys, typically in <2.6% of hauls in any year. Of the GRUND surveys, it was captured in approximately 1.7% of hauls in the central, northern and southern Adriatic Sea (Marano et al. 2003). In addition to the Adriatic Sea, the MEDITS programme operates on the northern Mediterranean coast almost continuously from Spain to the Aegean Sea (Baino et al. 2001). Six trawl surveys are carried out each year in the coastal areas of four geographically defined areas: western (Morocco, Spain, France), western central (Tyrrhenian, Corsican, Sardinian and Sicilian coasts), eastern central (Adriatic, Ionian and Albanian coasts) and eastern (Aegean Sea). A total of 6,336 tows were performed between 1994 and 1999 in depths ranging from 10 to 800 m. This skate was captured in 1.4% of the hauls in the southern MEDITS survey in 1998 and 1999, and was recorded in only nine hauls in the western central area (Baino et al. 2001). Also, eight specimens were reported between 2006 and 2013 from the MEDITS surveys around the Balearic Islands (Guijarro et al. 2013). However, uncertainty exists as to the validity of the identification of this species. It is suspected that earlier surveys may have confused it with Sandy Skate (Leucoraja circularis) and/or Sharpnose Skate (Dipturus oxyrinchus).  White Skate is common but infrequently encountered off the Balearic Islands (northwest Mediterranean Sea). A monitoring program of the landings in Mallorca in 2009 reported 27 specimens in 65 days of sampling, both from artisanal and bottom trawl fisheries, comprising 0.44% of the landed elasmobranch biomass (Morey and Navarro 2010). Also, several monitoring programs on artisanal fisheries have reported the occurrence of the species around the archipelago (e.g., Morey et al. 2006). This identified an area of high abundance of the species, where a fishery targeting White Skate exists. From other regions within the Mediterranean Sea, only one specimen was caught with a bottom trawl net by a commercial vessel in Livorno (Ligurian Sea) in 2003 (Serena et al. 2005). Similarly, in the northwest Ionian Sea, only a single individual was caught in 1997 (Sion et al. 2003). This skate was present in surveys of the Aegean Sea between 1995 and 2000, albeit in very low numbers (catch per unit effort of 0.03 individuals or 0.11 kilograms per hour) amounting to 14 individuals out of a total of >50,000 sharks and rays captured (Damalas and Vassilopoulou 2011). When this survey was repeated between 2003 and 2006, no specimens were caught, indicating possible local extinction (Damalas and Vassilopoulou 2011). From the data presented it can be inferred that this species is now very rare in the Mediterranean region, and the MEDITS survey suggests a substantial reduction in geographic range. In fact, this species was only recorded from the western area of this survey (Morocco, Spain, France). Evidence from the Gulf of Lions survey suggests its presence along the French coast may be doubtful. As described above, Aldebert (1997) reported that the species was historically absent from the Gulf of Lions, and the MEDITS survey data also cast doubt over its occurrence along the French coast. The current distribution represents a small fraction of its former range. From the former frequency of capture in the western Mediterranean Sea it can be inferred that this species has undergone a substantial but currently unquantifiable decline in abundance and extent of occurrence. The species is suspected to have declined by >50% over the past three generations (75-90 years) in European waters based on anecdotal evidence that suggests localized extinctions.

habitat:
This is a demersal species of sandy and detrital bottoms from coastal waters to the upper slope region between approximately 40 and 400 m and occasionally down to 500 m (Capapé 1976, Stehmann and Bürkel 1984, Serena 2005). Du Buit (1974) reports this species to be more prevalent in rocky habitats, though a local centre of abundance off the Balearic Islands is found over sandy and detrital bottoms at a depth range of 30-40 m, and some captures were reported at between 20 and 22 m (Morey et al. 2006). Little is known of this species’ life history and ecology. Estimates of size at maturity are 120-130 cm total length (TL) (Capapé 1976). Kadri et al. (2014) examined 320 specimens (39–160 cm TL) from Tunisian waters; the smallest mature fish were 110 cm TL (male) and 120 cm TL (female). They reported a length at 50% maturity (L50) of 119 cm TL (94 cm disc width; DW) for males, and 129 cm TL (95 cm DW) for females. The age at maturity was estimated at 19.7 and 23.5 years for males and females, respectively, with the youngest mature female reportedly 17 years old. The oldest male reported in the study was 32 years, and the oldest female was 35 years. Longevity was estimated at 51.3 and 76.8 years for males and females, respectively, and the natural mortality was estimated as 0.17 year-1. The Von Bertalanffy growth parameters were L∞= 177.6 cm, k= 0.06 year-1 and t0= -1.28 year for males, and L∞= 199.6 cm, k= 0.04 year-1 and t0= -1.28 year for females. Whilst improved studies to validate the ageing are needed, the results from Kadri et al. (2014) would infer a generation length in the range of 25-30 years. As the captive individuals at the Galway aquarium laid an egg at the age of seven, better data on age at maturity are required. Maximum recorded size is 200 cm TL, although it rarely exceeds 150 cm TL (Bauchot 1987). The gestation period is 15 months and females produce between 55 and 156 ova per year; egg cases are 160 to 200 mm in length and 130 to 150 mm in width (Stehmann and Bürkel 1984, Serena 2005). One to two egg capsules appear to be contained in each female’s oviducts at one time (Kadri et al. 2014).

threats:
Northeast Atlantic Skates are an important component of demersal fisheries in the Northeast Atlantic (Holden 1977, ICES 2013). Targeted fisheries that existed in certain areas ceased after localised depletion but this species may still be taken as bycatch in demersal fisheries. It has been listed as a prohibited species since 2009, and therefore it should be discarded, but neither discard levels nor survivorship after release are known. Landings of this skate as reported by France from the North Sea and eastern English Channel are likely the result of misidentification or incorrect use of species codes (ICES 2012). Similarly, landings reported by Scotland from the North Sea are also very unlikely, and probably refer to Shagreen Skate or Sandy Skate. Improved market sampling is required to fully ascertain the status of this species in fisheries. Mediterranean Sea This skate is a bycatch of the multi-species trawl fisheries operating within its Mediterranean range. Benthic trawl effort has increased both numerically and technologically in the shelf and slope area of the Mediterranean Sea over the last 50 years. The change in characteristics of fisheries operating in the Gulf of Lions provides an insight into the change in Mediterranean fishing effort over time. The area was initially exploited by small-scale benthic trawl fisheries, comprising 27 small, low-powered boats (total nominal horsepower of 2,700 hp). Since then, effort increased seven-fold to a total nominal horsepower of 19,940 hp between 1974 and 1987. Aldebert (1997) reported that half of the fishing effort within the Adriatic Sea was since redirected to target small pelagic fish; however, this sea is subject to trawling mainly by Italian, Croatian, Slovenian, and Albanian fleets, from which no landings data are available (Jukic-Peladic et al. 2001). The large body size, slow growth, low fecundity and large size of juveniles make this species especially vulnerable to fishing exploitation when compared to other skates (Brander 1981, Walker and Hislop 1998, Dulvy et al. 2000, Dulvy and Reynolds 2002). Moreover, although only large individuals may be landed for consumption, most size classes are likely to be taken in fishing nets, including the eggs (which are often found in the trawl cod-end, Ragonese et al. 2003), as the legal mesh size used in much of the Mediterranean Sea is ~ 20 mm.

conservationAction:
Northeast Atlantic The European Community’s Total Allowable Catch (TACs) and quota regulations listed White Skate as a prohibited species in 2009, specifying that European Union (EU) vessels are prohibited to fish for, retain on board, transship or land this species in EU waters west of Scotland and Ireland, the Celtic Seas, the English Channel, the Bay of Biscay, Iberian waters and Madeira (CEC 2011). The regulations also state that this species must be promptly released unharmed to the extent practicable. White Skate is listed for protection under the United Kingdom’s Wildlife and Countryside Act. It is also listed on the Oslo and Paris Conventions for the protection of the marine environment of the Northeast Atlantic (ICES 2012). Mediterranean Sea This skate is listed in Annex II of the Barcelona Convention. Parties to the Convention agreed in 2012 that elasmobranch species listed in Annex II of the Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean—which includes Recommendation GFCM/36/2012/1—cannot be retained on board, transshipped, landed, transferred, stored, sold or displayed, or offered for sale, and must be released unharmed and alive, to the extent possible. This species is also listed in Appendix III of the Bern Convention, affording it protection in the Mediterranean Sea from: i) all forms of deliberate capture and retention and deliberate killing; ii) deliberate damage to or destruction of breeding or resting sites; iii) deliberate disturbance, particularly during the period of breeding, rearing and hibernation, insofar as disturbance would be significant in relation to the objectives of the Convention; and iv) deliberate destruction or taking of eggs from the wild or keeping these eggs even if empty (Bern, 19.IX.1979). Additionally, the possession of and internal trade of species listed, alive or dead, including stuffed animals and any readily recognisable part or derivative thereof, where this would contribute to the effectiveness of the provisions of the article. At a national level, Spain (only in the Mediterranean Sea), Italy and Greece, as contracting parties to the Bern and Barcelona conventions have protected White Skate. Malta listed the species as one of the 14 elasmobranchs of national interest whose exploitation may be subject to management measures. In Israel all chondrichthyans (sharks, rays, skates and chimaeras) are protected. In Tunisia, the Gulf of Gabès (where this species is relatively abundant; Kadri et al. 2014) is closed to trawling fisheries from July to September. The Mediterranean Large Elasmobranch Monitoring project MEDLEM was adopted at the Scientific Advisory Committee meeting (FAO 2005) for data collection within the Mediterranean basin on large elasmobranchs. It includes White Skate as one of the monitored species.

useAndTrade:
There is no use or trade information on this species in Europe.

redListContributors:
Fordham, S., Pasolini, P., Notarbartolo di Sciara, G., Serena, F., Tinti, F. & Ungaro, N.


redListCategoryRationale:
European regional assessment: Endangered (EN) Blackchin Guitarfish (Glaucostegus cemiculus) is a demersal, shallow water species. It is large with low fecundity and therefore likely to have a slow, vulnerable life history. Most information comes from West Africa, but similar patterns of exploitation and retention are expected in the Mediterranean Sea, so we can infer a regional status from this information. It is taken as bycatch by international trawling fleets, artisanal gillnet fisheries and bottom trawl cephalopod fisheries operating within its range. A decrease in overall landings and reduction in the size of specimens landed have been observed since the 1990s. A projected decline of ≥ 50% within three generations (15−30 years) is suspected based on severe declines in other guitarfishes and wedgefishes, the continuation of fishing pressure in shallow coastal habitats, and the potential for fishing effort to further target guitarfish for their highly valued fins, particularly in the absence of other sharks. For these reasons, Blackchin Guitarfish is assessed as Endangered in the European region under Criteria A3bd.

range:
In the Northeast Atlantic, this species occurs off the northern coast of Portugal and southwards to the west coast of Africa (Ebert and Stehmann 2013). In the Mediterranean Sea it appears more prevalent in the southern and eastern regions (Capapé 1989). The depth range spans from shallow waters to ~100 m.

population:
Based on anecdotal evidence, this species was historically common throughout the northern Mediterranean Sea. In the late 19th century, Doderlein (1884) commented on the daily presence of this species on the Palermo fish market. In the early 20th century, it was considered a typical inhabitant of sandy habitats around the Balearic Islands (De Buen 1935). It has disappeared from bottom trawl surveys conducted from the Alboran to Aegean Sea by the Mediterranean International Trawl Survey programme, which suggests it may have been driven to local extinction in this area (Relini and Piccinetti 1991). Trawl surveys in the Adriatic Sea similarly did not detect this species between 1948 and 2005, indicating further local extinction (Ferretti et al. 2013). This guitarfish appears to be present only in parts of the southern Mediterranean basin (e.g., Gulf of Gabès and perhaps elsewhere along the more lightly-fished African Mediterranean coast) where it is still caught as bycatch, but with a large fraction of immature individuals (Enajjar et al. 2008, Bradaï et al. 2012, Echwikhi et al.2014). This species was once considered common in the southern Mediterranean Sea (Whitehead et al. 1984), particularly around the Gulf of Gabès (Bradaï et al. 2006) and east coast of Tunisia (Quignard and Capapé 1971). Recent reports show that this is still a common species off Turkey, particularly in the Iskenderun Bay area (Soldo et al. 2014).

habitat:
This guitarfish occurs in marine and brackish waters in subtropical areas. It is a demersal species, living over sandy or muddy substrates, with a depth range that spans from shallow water to ~100 m. The presence of all size classes in the southeast region of the Gulf of Gabès (Zarzis, Djerba) suggests that conditions for reproduction and development are favourable in this area and may be used as nursery habitat (Bradaï et al. 2006). This species is live bearing with yolk-only nutrition. The gestation period takes eight to ten months, and it reproduces once per year (Enajjar 2009); each female carries four to 12 embryos. Size at birth is ~365−380 mm total length (TL). Recent reports show that specimens fished from Tunisian waters do not exceed 202 cm TL and the development of the ovaries and uterus indicate that females begin to mature at 131 cm TL, while males reach sexual maturity at 118 cm TL (Enajjar et al. 2012). Whitehead et al. (1984) reported the maximum TL as 180 cm, however within the Gulf of Gabès in the southern Mediterranean Sea the maximum reported TL is 192 cm for males and 230 cm for females. The size at maturity is 110 and 100 cm TL for females and males, respectively. The generation length of the species is between five to ten years.

threats:
This species is taken as bycatch by international trawling fleets, artisanal gillnet fisheries and bottom trawl cephalopod fisheries operating within its range. Generally, it is threatened by capture in inshore trawls and static nets. In the Gulf of Gabès, it supports targeted demersal artisanal fishing by gillnets from April to August (Bradaï et al. 2006); neonates and females with encapsulated eggs are also caught in shallow water fisheries in these waters, and bottom trawlers catch juveniles throughout the year (Bradaï et al. 2006).

conservationAction:
In 2013, the European Union (EU) banned the removal of shark fins on board vessels (CEC 2013), in line with advice from the International Union for Conservation of Nature Species Survival Commission’s Shark Specialist Group and other shark fishery experts, in order to enhance enforcement of the 2003 EU ban on shark finning (CEC 2003) and facilitate improved shark fishery data collection. In 2011, the European Union (EU) put in place a regulation (CEC 2011) prohibiting EU vessels from fishing for guitarfishes (Rhinobatidae) in EU waters of the International Council for the Exploration of the Sea (ICES) sub-areas I (Barents Sea), II (Norwegian Sea, Spitsbergen and Bear Island), III (Skagerrak, Kattegat, Sound, Belt Sea, and Baltic Sea), IV (North Sea), V (Iceland and Faroe Islands), VI (Rockall, northwest coast of Scotland and North Ireland), VII (Irish Sea, West of Ireland, Porcupine Bank, English Channel, Bristol Channel, Celtic Sea, and Southwest of Ireland), VIII (Bay of Biscay), IX (Portuguese waters), X (Azores grounds) and XII (north of the Azores), but not in the Mediterranean Sea.In 2012, parties to the Barcelona Convention agreed that this species (as listed in Annex II of the Specially Protected Areas and Biological Diversity Protocol for the Mediterranean) cannot be retained on board, transshipped, landed, transferred, stored, sold, displayed or offered for sale, and must be released unharmed and alive, to the extent possible, pursuant to Recommendation GFCM/36/2012/1 (FAO 2012).The harvesting trends of the species should be monitored. 

redListContributors:
Notarbartolo di Sciara, G., Morey, G, Brahim, K., Camara, L., Litvinov, F., Dulvy, N., Doumbouya, F., Ducrocq, M., Heenan, A., Sidi, N. & Fordham, S.


redListCategoryRationale:
European regional assessment: Endangered (EN) Common Guitarfish (Rhinobatos rhinobatos) is a large-bodied benthic species that occurs at depths of zero to 180 m. It is widespread in the eastern Atlantic and Mediterranean Sea, but is subjected to fishing pressure throughout most of its range. This species is targeted in east African coastal waters, where its meat is exported within the region and its fins are exported to the Asian fin trade market. It is targeted in inshore coastal habitats by subsistence fisheries, and is also taken as bycatch in shrimp trawl fisheries, bottom trawl cephalopod fisheries and artisanal gill net fisheries. In the northern Mediterranean Sea, guitarfishes were historically quite common, but its absence during research trawl surveys conducted in 1994-1998 from the Alboran to Aegean Sea and absence from landings reported in Mazara del Vallo (Italy) suggest that it is now locally extinct. In areas of the southern Mediterranean Sea (e.g., Gulf of Gabès, and perhaps elsewhere along the still relatively lightly fished Mediterranean-African coast) guitarfishes are still present in catches, but with a large fraction of immature individuals.  The rarity and low rate of encounter for this species makes it impossible to assess changes in abundance over time. However, given evidence for local extinction in parts of the Mediterranean Sea and intense and continued fishing pressure in West Africa, this species is suspected to meet the threshold for Endangered, having declined by at least 50% in three generations.

range:
In the Northeast and Eastern Central Atlantic, this species occurs from the southern Bay of Biscay down to Morocco and further southwards (Ebert and Stehmann 2013). In the Mediterranean Sea, it occurs throughout, but it appears more prevalent in the southern and eastern regions (Capapé 1989, Whitehead et al. 1984), particularly in the Gulf of Gabès (Quignard and Capapé 1971, Enajjar et al. 2008), and may be locally extinct in the northern region of the Mediterranean Sea. Its depth range is zero to 180 m.

population:
Little is known about population size, but fishermen's knowledge and trawl survey data suggest a marked decline driven by unregulated fishing throughout this species’ range. Anecdotal evidence suggests that this species was historically common throughout the northern Mediterranean Sea. In the late 19th century Doderlain (1884) commented on the daily presence of this species in the Palmero fish market. In the early 20th century, it was considered a typical resident over sandy substrates around the Balearic Islands (De Buen 1935). The International Trawl Survey in the Mediterranean (MEDITS) surveyed from the Alboran to the Aegean Sea between 1994 and 1999, and failed to catch this species (Baino et al. 2001), suggesting a marked decline in abundance. This lead Relini and Piccinetti (1991) to report this species as locally extinct in the northern regions of the Mediterranean Sea.In the southern and eastern basins of Mediterranean Sea, observations from the 1970s and 1980s indicate that this species was prevalent (Quignard and Capapé 1971, Whitehead et al. 1984, Echwikhi et al. 2012, 2013). This species is still caught in the Gulf of Gabès and potentially elsewhere along the southern coast of the Mediterranean Sea where fishing pressure has been less intensive. All sizes and sexes of this species are landed in the Gulf of Gabès and the proportion of mature and immature individuals varies with season and capture area (Enajjar 2009). Recent reports reveal that this species is still common in Turkish waters, particularly in the Iskenderun Bay area (Soldo et al. 2014) where it is landed as bycatch (Bausta et al. 2008). The demersal nature of this species and the localised decline within the northern Mediterranean Sea indicate that there are low levels of connectivity between geographical subpopulations. Given the susceptibility this species has to fisheries throughout its range, and marked declines in the Mediterranean Sea, it is suspected and inferred that this population is decreasing in European waters. Given evidence for local extinction in parts of the Mediterranean Sea and intense and continued fishing pressure in West Africa, this species is suspected to have declined in Europe by at least 50% in three generations.  

habitat:
This bottom-dwelling species can be found over sandy, muddy, shell and occasionally macroalgal covered substrates (Whitehead et al. 1984, De Buen 1935). It inhabits shallow areas of in the intertidal zone and waters < 180 m deep. It tends to swim slowly along the sea bottom or partially buries itself under the substrate, feeding on benthic invertebrates and fish (Patokina and Litvinov 2005). This is an aplacental live bearing species that gives birth in late summer to early autumn following a gestation period of 10−12 months. Mating and ovulation take place after parturition. The average uterine fecundity is 5.34 young per year with each pup measuring ~ 30 cm total length (TL) at birth. The size at maturity for females and males are 79 and 70 cm TL, respectively, and the smallest gravid female observed is 75 cm TL (Enajjar et al. 2008). Females reach larger sizes compared to males, with the largest male being ~ 140 cm TL and the largest female being 162 cm TL, both were caught in the Gulf of Gabès (Capapé et al. 1996). The age at maturity is two to three years (Ismen et al. 2007). The maximum age is at least 24 years (Başusta et al. 2008). The generation length is 13.5 years.

threats:
The biology and inshore habitat preferences of this species make it highly susceptible to population depletion. Although wide-ranging, this species likely sustains fishing pressure throughout most of its range. Its coastal habitat makes it an easy target for artisanal fisheries and it is likely to be caught as bycatch in many commercial fisheries operating along the majority of the Mediterranean coastline, including the Egyptian commercial trawl fishery off the coast of Alexandria. This species is likely discarded as bycatch, but may also be retained for its meat and fins, as has been observed in east African fisheries that regularly catch other species of guitarfish. Nursery grounds are also likely impacted by human activities in many areas. 

conservationAction:
In 2011, the European Union  (EU) prohibited the retention of Atlantic (but not Mediterranean) guitarfishes (Rhinobatidae) in European Union waters of International Council for the Exploration of the Sea (ICES) sub-areas I (Barents Sea), II (Norweign Sea, Splitzbergen and Bear Island), III (Skagerrak, Kattegat Sound, Belt Sea, and Baltic Sea), IV (North Sea), V (Iceland and Faroes Grounds), VI (Rockall, northwest coast of Scotland and North Ireland), VII (Irish Sea, West of Ireland, Porcupine Bank, English Channel, Bristol Channel, Celtic Sea, and Southwest of Ireland), VIII (Bay of Biscay), IX (Portuguese waters), X (Azores Grounds), and XII (North of the Azores).In 2012, this species was added to Annex II of the Barcelona Convention. Parties to the Convention agreed that elasmobranch species listed in Annex II of the Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean, which includes Recommendation GFCM/36/2012/1, cannot be retained on board, transshipped, landed, transferred, stored, sold or displayed or offered for sale, and must be released unharmed and alive, to the extent possible. In 2013, the EU banned the removal of shark fins on board vessels (CEC 2013), in line with advice from the International Union for the Conservation of Nature’s Shark Specialist Group and other shark fishery experts, in order to enhance enforcement of the 2003 EU ban on shark finning (CEC 2003) and facilitate improved shark fishery data collection.

useAndTrade:
This species is caught in artisanal fisheries and it is likely to be caught as bycatch in many commercial fisheries. This species is likely discarded as bycatch, but may also be retained for its meat and fins.

redListContributors:
Notarbartolo di Sciara, G., Morey, G, Marshall, A., Compagno, L.J.V., Mouni, A., Hicham, M., Bucal, D., Dulvy, N., Heenan, A. & Coelho, R.P.


redListCategoryRationale:
European regional assessment: Data Deficient (DD) Lusitanian Cownose Ray (Rhinoptera marginata) is a large bentho- and semi-pelagic ray, known from the western coast of Africa and Mediterranean Sea. It is apparently very rare in most of the Mediterranean Sea. This species is commonly caught with multiple gear types, and is particularly vulnerable to coastal purse seine, gillnet and trammel net fisheries. Coastal fishing pressure is generally intensive along the western African coast, and this ray is an important component of catches in areas for which data are available. It forms large schools, meaning that large numbers can be caught in a single haul. Heavy fishing pressure has caused declines in other Rhinopterids, for example Rhinoptera brasiliensis is thought to be in decline in southern Brazil as a result of intensive inshore fisheries. Although no species-specific age data are available, generation length is estimated at about 11 years, based on data for other Rhinopterids, as well as very low fecundity (possibly only one pup per litter). This species is assessed as Data Deficient given the lack of information on population size and decline.

range:
This ray is rare throughout the Mediterranean Sea and is absent from the Black Sea. It is relatively common in the Levantine basin and is sporadically found in the eastern Adriatic Sea. In the Northeast Atlantic it occurs along the coast of southern Portugal. Its range extends southwards into the Eastern Central Atlantic, where it is found along the western coast of Africa, off Morocco, Mauritania and Senegal. Its depth range is zero to 100 m.

population:
No data are currently available to analyse population size or structure. In the Mediterranean Sea this species is apparently rare and was found in only two hauls (in the eastern Ionian Sea) of 6,336 total hauls during the International Trawl Survey in the Mediterranean (MEDITS) conducted between 1994 and 1999 at depths of 10–800 m (Baino et al. 2001, Ferretti et al. 2013). It was historically considered rare in the Adriatic Sea where it was infrequently encountered off the coast of Dalmatia (Marchesetti 1882, Faber 1883).Within the Mediterranean Sea this ray appears to be most abundant in the Levantine basin, although data are insufficient to estimate population trends. Even historically it was considered less rare in the Levantine Sea than in other parts of the Mediterranean Sea (Doderlein 1884). It is considered common off Israel (Golani 2006), reported off Syria (Saad 2006), Cyprus (Hadjichristophorou 2006), Egypt (Dieuzeide et al. 1953), and Turkey (Bilecenoglu et al. 2002, Basusta et al. 2012). For the rest of the Mediterranean Sea, available records are historical, such as observations in the fish markets of Mallorca (Barceló and Combis 1868).Based on the apparent rarity of this species and subpopulation decline of other Rhinopterids such as Rhinoptera brasiliensis, which is thought to be have declined in southern Brazil as a result of intensive inshore fisheries, it is inferred a subpopulation decline in European waters as well.

habitat:
This is a bentho- and semi-pelagic species that occurs in tropical to warm temperate coastal waters mostly to only 30 m depth but occasionally to 60 m, and even 100 m in the Mediterranean Sea (Ebert and Stehmann 2013). Preferred habitat includes shallow bays, lagoons and estuaries. Basusta et al. (2012) suggest that the Yumurtalik Bight in Iskenderun Bay, Turkey may be a nursery area for this species. This ray is live bearing with yolk sac and has a gestation period of up to one year; it possibly produces only one young per litter (Valadou et al. 2006). Further details on the reproductive biology, such as size at sexual maturity, are not known (Ebert and Stehmann 2013). Data from Mauritania indicate size at sexual maturity is 77 and 80 cm DW (disc width) for males and females, respectively. Maximum recorded DW ranges from 150−200 cm, but most are found at smaller sizes of 65−75 cm DW. While no age data are available for this species, they are for its congener, Cownose Ray (Rhinoptera bonasus), and can be used as a proxy for generation length. Cownose Ray matures between four and five years and females live more than 18 years in the northern Gulf of Mexico (Neer and Thompson 2005). Generation length is estimated at 11.25 years. Although the generation length for Lusitanian Cownose Ray may differ from Cownose Ray, 11 years could be considered a rough proxy.

threats:
This species is taken by bottom trawl, trammel net, longline, and hook and line (Schneider 1990), and is of little commercial importance for human consumption in the Mediterranean region. Schooling behaviour in shallow water makes it particularly vulnerable to target fisheries (Ebert and Stehmann 2013). Fishing pressure from commercial trawl fisheries is generally intensive on the continental shelf and upper slope of the Mediterranean Sea (at depths ranging from 50 to 700–800 m), which this species may be vulnerable to, although no data are available (Colloca et al. 2003, Massuti and Moranta 2003). Inshore fisheries in Brazilian waters have driven Cownose Ray to local extinction, indicating that similar fisheries operating in Mediterranean waters likely pose a similar threat to Lusitanian Cownose Ray. This ray has very low fecundity, a generation period inferred to exceed 11 years, and is relatively large in size. These sensitive life history characteristics, combined with high catchability in intensive coastal fisheries suggest that continued fishing pressure is likely to be unsustainable. Similar species such as Cownose Ray are destructive to commercial oyster and clam beds, so persecution from aquaculture operators may also be possible. 

conservationAction:
Skate and ray Total Allowable Catch (TAC) limitations were established in 2009 for a number of International Council for the Exploration of the Sea Divisions including Division IX (Iberian waters) where Lusitanian Cownose Ray exists. The TAC for Division IX covering all skate and ray species has decreased annually since it was first introduced in 2009, currently set at 3,800 tonnes in 2013. Further research should be conducted on the population size and trends of the species.

useAndTrade:
The species is of little commercial importance for human consumption in the Mediterranean region.

redListAssessors:
Ferretti, F., Notarbartolo di Sciara, G., Serena, F. & Ducrocq, M.


taxonomicNotes:
This species is sometimes called Spotted Electric Ray, which has resulted in confusion between this species and the Blackspotted Electric ray (T. foscomaculata).

redListCategoryRationale:
European regional assessment: Least Concern (LC)Spotted Torpedo (Torpedo marmorata) is a demersal species that seems to be widespread in the eastern Atlantic and Mediterranean Sea. It is not targeted by commercial fisheries, but is taken as bycatch in demersal trawl fisheries, coastal trammel nets, and bottom longlines, then usually discarded. Trawl survey data indicate that this species is more common than other Torpedo species in the northern Mediterranean Sea, with a stable population trend in waters south of France, and possible increasing trend in coastal waters of Italy. Conversely, a 24% decline was reported in the Adriatic Sea between 1948 and 2005. Owing to its broad geographical range and low commercial value, combined with an absence of evidence for declines (except in the Adriatic Sea), the population is suspected to be stable overall; therefore Spotted Torpedo is assessed as Least Concern in European waters. In the future, fisheries bycatch and landings should be monitored given that little is known of population trends or the impact of fisheries off western Africa and the rest of its Northeast Atlantic range, where demersal trawl effort is high.

range:
The species is found in the Eastern Atlantic and Mediterranean Sea: from the northern U.K., south to the Cape of Good Hope in South Africa, and throughout the Mediterranean Sea (Whitehead et al. 1984). The depth range is 10−100 m.

population:
The trends in abundance are uncertain for the European region because beam trawl surveys only catch this species in low numbers and it is not commercially targeted. Reports indicate that it is more common than the other two Torpedo species in the Adriatic Sea: Ocellate Torpedo (Torpedo torpedo) and Great Torpedo (Torpedo nobiliana; Bini 1967). The International Trawl Survey in the Mediterranean programme covers the European Mediterranean coast almost continuously from western Morocco and Spain in the west to the Aegean Sea in the east. A total of 6,336 tows were performed between 1994 and 1999 at depths of 10−800 m. This species occurred in 317 of 6,336 hauls (Baino et al. 2001), indicating that it is relatively abundant in the northern Mediterranean Sea compared with other elasmobranch species recorded. Bertrand et al. (2000) and Aldebert (1997) both found no evidence of population decline for this species on the southern coast of France. Analysis of trawl survey data in the northern Tyrrhenian Sea showed that the population is increasing in the coastal zone, probably owing to the low commercial value of the species (Ferretti et al. 2005). Conversely, Ferretti et al. (2013) reported a 24% population decline in the Adriatic Sea between 1948 and 2005.

habitat:
This benthic species occurs on sea grass, rocky reefs and soft or stony bottoms at depths of 10−100 m (Serena 2005). It avoids temperatures above 20°C.In Egyptian and Tunisian Mediterranean waters, the largest recorded male was 39.5 cm total length (TL), while the largest female was 61.2 cm TL (Capapé 1979, Abdel-Aziz 1994). In the western English Channel, the largest male recorded was 43 cm TL. Males mature at 21−29 cm TL and females at 31−39 cm TL. Mellinger (1971) reported that females mature at ~12 years and live to 20 years of age, while males mature at five years and live to 12−13 years. This aplacental live-bearing species has a gestation period of 10−12 months (Abdel-Aziz 1994). It probably breeds every two years, and fecundity appears to increase with the size of the female (Capapé 1979, Abdel-Aziz 1994). Females produce three to 18 pups, measuring 10−14 cm TL at birth. The breeding season is reportedly November to December (Mellinger 1971).  

threats:
This species is not commercially fished, but it is taken as bycatch in demersal trawl fisheries, coastal trammel nets and bottom longlines and often discarded at sea due to its low commercial value (Minervini et al. 1985). As a result of this discarding and the grouping of landings data with other rays, little information is available on the catch of this species. Fishing pressure from demersal trawl fisheries is relatively intensive on the continental shelf off western Africa.

conservationAction:
No species-specific management or conservation measures are in place. Precautionary conservation measures should include the live release of individuals caught, improved monitoring of fisheries bycatch, identification of important nursery areas, and the establishment of protected areas for such demersal species. Research is also required on threats, population size, trends and capture in fisheries throughout the species’ range, particularly in the Northeast Atlantic where data are scarce.

useAndTrade:
The species is not thought to be exploited nor traded commercially. Historically, in Adriatic Sea, Torpedo marmorata was sold smoked although its meat was of the lowest commercial value (Ninni 1912).

redListAssessors:
Notarbartolo di Sciara, G., Serena, F., Ungaro, N., Ferretti, F., Pheeha, S., Human, B., McCully, S. & Buscher, E.


taxonomicNotes:
The name as allocated to the southern African material is provisional. Work underway suggests that there may be a tropical species from off southern Mozambique that is more similar to true T. nobiliana from the North Atlantic than to specimens from Namibia and the Cape. Work is underway to clarify the taxonomy of the Indian Ocean species.

redListCategoryRationale:
European regional assessment: Least ConcernGreat Torpedo Ray (Torpedo nobiliana) is a widespread, large electric ray found in the Northeast Atlantic and Mediterranean Sea. Adults are pelagic and/or semi-pelagic, swimming in the water column from depths of zero to 800 m, whereas juveniles are mainly benthic and live on soft-substrate and reef habitat in shallower water. This electric ray is caught with bottom trawls and line gear. It is usually discarded at sea, resulting in limited catch data. Very little catch data are available from scientific trawl surveys. Given that this is a widespread pelagic species that is rarely caught in fisheries, Great Torpedo Ray is assessed as Least Concern in European waters. Further research is required to assess the impact of fishing activities on populations and important habitats. 

range:
The species is found throughout much of the Atlantic. In the Northeast Atlantic, this ray occurs from the northern British Isles to Morocco. It is also present in the Mediterranean Sea, but not the Black Sea (Stehmann and Bürkel 1984, Serena 2005). Its depth range is zero to 800 m.

population:
Few data are available for inferring population trends for this species across its range. Low frequency of occurrence in bottom trawl surveys from the Northeast Atlantic and Mediterranean Sea suggest that it is relatively rare. In the Northeast Atlantic, it is occasionally caught in surveys along the Atlantic shelf, but not in sufficient numbers to infer population trends. During the International Bottom Trawl Survey in the Mediterranean (MEDITS), it was captured in 73 of 6,336 hauls conducted throughout the northern Mediterranean Sea at depths of 10−800 m between 1994 and 1999, and it appears to be more common in the western basin (Baino et al. 2001). In the Gruppo Nazionale Demersali Italian scientific trawl surveys, this species was reported in low numbers from several locations along the Italian coast, including Sicily, Calabria, Gulf of Taranto, Sardinia, and the northern Tyrrhenian Sea. It is rarely recorded off Tuscany and Corsica (Relini et al. 2000, Ferretti et al. 2005). Historical records report this ray in the northern Tyrrhenian Sea (D’Ancona and Razzauti 1937, Foresi 1986), Ligurian Sea (Ariola 1904, Brunelli and Bini 1934) and Gulf of Lion (Aldebert 1997), but it is difficult to evaluate previous trends in abundance as most of these reports are qualitative and do not specify catch rates for this species. Despite the lack of data suggesting abundance and population trends, it is suspected that the European subpopulation is stable owing to the limited interaction with fisheries.

habitat:
This electric ray occurs at depths of zero to 800 m. Juveniles are mainly benthic on soft substrates and coral reef habitats at depths of 10−150 m, and sometimes considerably deeper (up to 350 m). Adults may be pelagic or semi-pelagic, solitary, and reportedly capable of migrating over great distances (Ebert and Stehmann 2013). Specimens were captured in MEDITS surveys throughout the depth range surveyed (10−800 m), but mostly at depths of 200−500 m (Baino et al. 2001). Embryos of this live-bearing species rely on yolk-only nutrition. Large females reportedly have up to 60 embryos. The gestation period is ~12 months and size at birth is 20−25 cm total length (TL; Whitehead et al. 1984, McEachran and de Carvalho 2002). The smallest mature male ever reported was 55 cm TL, and the smallest mature female was 90 cm TL (Capapé et al. 2006). This species reaches a maximum size of ~180 cm TL (McEachran and de Carvalho 2002). 

threats:
Historically, this ray was valued for its liver oil, which was used in lamps prior to the use of kerosene oil. Presently, it is occasionally caught incidentally by bottom trawls and line gear in commercial and recreational fisheries. It is usually discarded at sea, resulting in limited data on catches and discard survival is unknown. The lack of catch data makes it difficult to determine population trends. As a large-bodied ray, it may be biologically vulnerable to depletion. The impact of bycatch on populations needs to be assessed. The species’ vulnerability to indirect effects of habitat degradation from destructive bottom trawling practices should also be assessed given that reef environments are suspected to be the preferred spawning habitat. 

conservationAction:
In 1999, the European Union (EU) introduced a Total Allowable Catch (TAC) for skates and rays of 6,060 tonnes (t) for fisheries operating in the Norwegian Sea and North Sea (International Council for the Exploration of the Sea [ICES] Division IIa and Subarea IV) based on landing statistics from the previous five years. This TAC has been progressively reduced by 8−25% annually to the current level of 1,256 t. As part of the TAC, the bycatch quota for vessels over 15 meters was set at 25% of live weight of catch retained on board per trip. For much of this period (1999−2014), the TAC was higher than reported landings and therefore not effectively constraining catches. Skate and ray TACs were established for other EU waters in 2009, including the Skagerrak and Kattegat (ICES Division IIIa) and from the northwest coast of Scotland and North Ireland to Portuguese waters (ICES sub-areas VI−IX) and have also been gradually reduced since then.Accurate monitoring of catches and research on historical abundance is needed to determine the status of subpopulations. Further research on life history characteristics is also required.

redListContributors:
Notarbartolo di Sciara, G., Serena, F., Ungaro, N., Ferretti, F., Holtzhausen, H., Smale, M. & Fordham, S.


redListCategoryRationale:
European regional assessment: Least Concern (LC) This electric ray occurs in the eastern Atlantic, from the southern Bay of Biscay, south to Angola and in the Mediterranean Sea. It is primarily coastal, found in inshore waters, although occasionally found to depths of more than 300 m. It is apparently more common in the southern than in the northern Mediterranean Sea. Trawl survey data available from the northern Mediterranean Sea indicate that it is less common than other electric rays (Torpedo spp.) in this area, and few data are currently available from the rest of the species’ range. This ray is taken as bycatch in demersal fisheries, including coastal artisanal fisheries, trawls and trammel nets, although no specific data are available on its capture.Population decline is suspected in European waters based on the apparent disappearance from areas in which it used to occur, perceived rarity elsewhere, and geographic overlap with coastal demersal fisheries. However, this is an untargeted electric ray whose post-discard survival may be relatively high because it is often caught in shallow waters, and it is most likely discarded at sea. For these reasons the species is assessed as Least Concern for this region. Demersal fishing pressure is relatively intensive in large areas of its range and there is need to further investigate the effect of fisheries and habitat pressures on this species.

range:
Within the Northeast Atlantic this electric ray occurs southwards from the southern Bay of Biscay beyond the Eastern Central Atlantic; records as far north as Belgium are considered questionable. It also occurs throughout the Mediterranean Sea, where it is most common in African waters. It does not occur in the Black Sea (Ebert and Stehmann 2013).

population:
In the Mediterranean Sea, this species is more common along the northern African (southern Mediterranean Sea) coasts. Surveys in the northern Mediterranean Sea suggest that it is uncommon and less abundant than Spotted Torpedo Ray (Torpedo marmorata) there. Common Torpedo Ray (T. torpedo) was recorded in 28 of 6,336 hauls conducted during the International Bottom Trawl Survey in the Mediterranean (MEDITS) in the northern Mediterranean Sea, from 1994-1999 at depths of 10-800 m (Baino et al. 2001). The species is rare around the Balearic Islands. In some regions where it was recorded in the past it is now undetectable by trawl surveys. For example in the Adriatic Sea (northern Mediterranean Sea), it was historically reported as rare in species lists but has not been recorded in recent trawl surveys (Jukic-Peladic et al. 2001). The species has been recorded in trawl surveys along the western coast of Africa (Gulyugin et al. 2006), but virtually no other information is currently available from throughout the rest of its range. In fact, the International Council for the Exploration of the Sea did not mention the species in the 2014 Working Group for Elasmobranch Fishes report, despite mentioning both Spotted Torpedo Ray and Great Torpedo Ray (T. nobiliana), indicating a likely absence from the region.

habitat:
This benthic ray is common in tropical waters, found on soft substrates, usually inshore, but also down to 70 m or occasionally to depths of more than 300 m (Gulyugin et al. 2006). The maximum recorded size is about 60 cm total length (TL; Serena 2005). In Egyptian waters size at maturity is 18 cm TL for males and 22 cm TL for females (Abdel-Aziz 1994). This is an aplacental viviparous species, with an apparent restricted, annual breeding season (Abdel-Aziz 1994). Birth usually occurs between March and September with 3-21 juveniles of 8-10 cm TL (Serena 2005). Litter size increases with the size of the female. Considering the available information for its congener Torpedo californica (Neer and Cailliet 2001), the species is suspected to mature between six and nine years, reaching a maximum age of 16 years. Generation length is therefore estimated to be 12.5 years.

threats:
This species is captured in demersal fisheries, including bottom trawls, trammel nets, and artisanal coastal fisheries. Even though it is edible, it is undesirable for human consumption (Ebert and Stehmann 2013) and landed by very few fisheries; it is most often discarded at sea. Post-discard survival may be relatively high because it is often caught in shallow waters, but there is no evidence for this as yet. It appears to be consistently present in the demersal catch of fisheries on northern Mediterranean shores, owing to the complete overlap between its range and coastal demersal fisheries. No information is currently available on catch of this species in the Northeast Atlantic or Eastern Central Atlantic region.

conservationAction:
Precautionary conservation measures should include the live release of individuals caught, improved monitoring of fisheries data, identification of important nursery areas and the establishment of protected areas for such demersal species. Improvement and implementation of elasmobranch monitoring programmes is required to obtain data from throughout the species’ range.

useAndTrade:
The species is landed in some ports of the North Thyrrenian Sea. The meat can be eaten after removal of electrical organs from the specimens and then deep fried.

redListAssessors:
Serena, F., Notarbartolo di Sciara, G. & Ungaro, N.


taxonomicNotes:
Taxonomy of the genus Centrophorus has been under debate, of which two species with sessile dermic denticles (thus different from C. squamosus) have been the focus. Their most conspicuous anatomical differences are maximum size and size at sexual maturity. The species assessed here, Centrophorus granulosus (Bloch and Schneider 1801), is to be considered the “larger” of the two species, and has been reported under the names C. granulosus, C. niaukang and C. acus. Although the taxonomic status is complex and still has not been fully resolved, the simplest classification is to describe the situation as C. uyato being newly split from the original C. granulosus assessment.Taxonomic confusion comes from both a long history of mistakes in the literature and problems with nomenclature. A recent review by White et al. (2013) included a re-description of the species and the settlement of a neotype. Genetic data also supported that this species is synonymous with a previously considered well-separated species, C. acus (Veríssimo et al. 2014).The present assessment follows the work of White et al. (2013) in the use of this name and uses only the relevant data provided in the original description by Bloch and Schneider (1801). The “large” specimen Bloch and Schneider (1801) studied was about 150 cm total length and is the originally described specimen named C. granulosus.

redListCategoryRationale:
European regional assessment: Critically Endangered (CR)The reproductive biology of this shark is characterized by low fecundity and late onset of maturity, making it sensitive to exploitation and population depletion. It was historically captured in Portuguese target fisheries and was also retained in bycatch. Targeted fisheries for, and reported landings of this species ceased with the introduction of a zero Total Allowable Catch for deepwater sharks in 2010. Nonetheless, this species is still likely caught incidentally and discarded, with low chance of survival following discard. The taxonomic issues associated with this species need to be resolved. In particular, the gulper shark genus (Centrophorus spp.) needs to be examined in order to determine the proper identification of this species in European waters. This species is regionally assessed in European waters as Critically Endangered under Criterion A4b based on both slow life history and steep declines in landings of 99% experienced and projected over the three-generation period (50-60 years).

range:
Considerable taxonomic confusion of the genus Centrophorus still persists (see Taxonomic Notes), so particular care must be taken when describing the range of this species. It has been reported in the Northeast Atlantic as C. niaukang (Muñoz-Chapuli and Ramos 1989), C. forme granulosus (Cadenat and Blache 1981) and C. granulosus (Bañón et al. 2008). It is probably a widespread species, capable of large migrations within its depth range. In the Northeast Atlantic it occurs off the United Kingdom, France, Spain (including the Canary Islands) and Portugal, including Madeira (Muñoz-Chapuli and Ramos 1989, Bañón et al. 2008, White et al. 2013). 

population:
Landings data from the International Council for the Exploration of the Sea (ICES) from the Portuguese coast, which is the main distribution range of this species, show a steep decline in catch from about 1,000 tonnes (t) in 1990 to < 100 t in 2004 (ICES 2006). A Delury depletion model, which assumed constant effort over the time series, was used to make a crude estimate of index of abundance. The model estimated that the stock has declined by between 80 and 95% of its initial size from when fishing began, although accurate identification of this species is uncertain. Despite inaccurate identification, this is the larger of the gulper sharks found in European waters, so it can be assumed that this decline would have had a greater effect on it, given the slower life history attributed to larger species. In 2010 the directed Portuguese longline fishery for this species reported catches had been reduced to zero (ICES 2013). While annual Portuguese landings from this fishery hovered around 100 t until 2008, landings reduced to two tonnes in 2009. It appears to be more likely that this reduction resulted from restrictive quotas for deepwater sharks, or from misidentifications, rather than an actual reduction in catches. Since 2002 only very few landings have been reported from areas other than Portugal, but included Subareas VI (west of Scotland) and VII (west/south/southwest of England/Wales/Ireland). Reported landings of this species United Kingdom vessels in Subareas VI and VII are considered to be misidentifications. Determining the population size and structure of this species is partially hindered by unresolved taxonomic issues (see Taxonomic Notes).The species has declined by 98.36% from 1990-2015, and it is projected to continue declining by 99.97%-99.99% for the three generation period (1990-2040 and 1990-2050; 50 and 60 years respectively). 

habitat:
This mid-sized, rare deepwater shark has a widespread global range, inhabiting the upper continental slopes and outer continental shelf area. This shark is likely demersal or benthopelagic and occurs at depths ranging from 100−1,490 m with most records between 300 and 800 m. It appears that pregnant females tend to segregate from the rest of the population (Cotton 2010).This species has a very low reproductive rate, producing litters between three and 12 pups (Compagno et al. 2005, Bañón et al. 2008, Cotton 2010, White et al. 2013). Size at birth is between 35 and 47 cm total length (TL; Bañón et al. 2008, Cotton 2010, White et al. 2013). Sexual maturity occurs for males at about 100−110 cm TL and for females about 137−148 cm TL (Yano and Tanaka 1986, Bañón et al. 2008, Cotton 2010, White et al. 2013). This mid-sized species can attain a maximum size of about 170 cm TL (Compagno et al. 2005, White et al. 2013). Age at maturity is estimated at 12 to 16 years in females and seven to eight years in males (Guallart 1998), with earlier estimates of four to five years for both males and females. The generation length of this is species is 17-20 years.

threats:
This is a widespread species that was historically targeted and is likely still caught as bycatch in the Northeast Atlantic with bottom trawls, long lines, fixed bottom nets, hook and line and pelagic trawls. In the Northeast Atlantic, deepwater fisheries have decreased in effort gradually over the past decade (Dransfeld et al. 2013, STECF 2014), but should still be monitored in case of future expansion, which could pose a threat to this shark.Due to ICES advice to end fishing for deepwater sharks, the European Union Fisheries Council in 2007 established and began gradual reductions of Total Allowable Catch (TAC) for this species and others. As a result, possible catches of this species began to be landed under the name of the non-regulated species Lowfin Gulper Shark (C. lusitanicus), taking advantage of the taxonomic ambiguity of this genus. When the TAC was reduced to zero in 2010, subsequent reported landings of this species have dropped to zero. Since this time, the deepwater shark TAC was amended to include all species of the genus Centrophorus to halt landings of this species under the non-regulated Lowfin Gulper Shark. It is likely that this species is still incidentally captured but is discarded as a result of the TAC, making it impossible to determine the level of or effects of exploitation occurring. This species likely has a low level of survival following discard, given the depth from which it is captured. 

conservationAction:
Based on advice from the International Council for the Exploration of the Sea to end fishing for deepwater sharks, the European Union Fisheries Council established a TAC (Total Allowable Catch) for this species in 2007 (CEC 2012). This TAC was gradually reduced and in 2010 it was set at zero. In 2011, the allowable bycatch was reduced from 10% to 3% of the 2009 TAC and in 2012 it was further reduced to zero (ICES 2013). In 2013, the list of species covered by the deepwater shark TAC was amended to include all species of the genus Centrophorus, thereby closing a loophole for landing Lowfin Gulper Shark. Taxonomic clarification of the genus is a high priority for the future management, regulation and control of this species.

useAndTrade:
This is a widespread species that was historically targeted.

redListAssessors:
Guallart, J., Walls, R.H.L. & Bariche, M.

redListContributors:
Fordham, S., Serena, F., Mancusi, C., Casper, B., Burgess, G.H., Ebert, D.A., Clarke, M. & Stenberg, C.


taxonomicAuthority:
Barbosa du Bocage & de Brito Capello, 1864

taxonomicNotes:
Scarcity of data for Centrophorus lusitanicus comes mainly from the taxonomic controversy of the genus Centrophorus and its probable confusion in many cases with other species in the area such as C. granulosus and C. uyato. Although some authors considered C. lusitanicus as synonymous with the two former species, recent morphometric and genetic studies confirm the validity of this species (White et al. 2013). Data from general books about the species must therefore be taken with caution.

redListCategoryRationale:
European regional assessment: Endangered (EN)Lowfin Gulper Shark (Centrophorus lusitanicus) has a limited geographic range, extremely low fecundity, and is subject to deepwater fisheries in the Northeast and Eastern Central Atlantic. Lowfin Gulper Shark, Gulper Shark and Little Gulper Shark (C. uyato) are taken in deepwater fisheries operating off Portugal and in areas of their range in the Eastern Central Atlantic. Lowfin Gulper Shark (C. lusitanicus) is estimated and projected to experience declines of >70% decline over three generations (50-60 years) in European waters, therefore qualifying as Endangered under criterion A4b.Bycatch levels and fisheries should be monitored throughout this species’ range, and it may prove to warrant a higher category in future, dependent on fishery effort. Species-specific monitoring of catch and population trends is urgently required for this biologically sensitive shark.

range:
In the Northeast and Eastern Central Atlantic, Lowfin Gulper Shark (Centrophorus lusitanicus) is distributed from Portugal, southwards along the West African coasts, including the Canary Islands. Records from anywhere other than the eastern Atlantic may be misidentifications (Ebert et al. 2013). This shark has never been recorded in the Mediterranean Sea. Its depth range is 300-1,400 m.

population:
Little specific information is available on the population of this species. However, information is available on population trends for the similar species, Gulper Shark (C. granulosus) and Little Gulper Shark (C. uyato), which occur within this species’ range. These sharks inhabit similar depth and geographic ranges and are exploited by the same fisheries, yet data for Lowfin Gulper Shark are scarce.  Identification problems commonly confuse this shark with its congener Gulper Shark, which is estimated to have undergone declines of 80-95% where it is fished in the Northeast Atlantic. ICES (2006) landings data from the Portuguese coast show a strong estimated decline in Little Gulper Shark catch from about 1,000 t in 1990 to less than 100 t in 2004. Estimated decline over 14 years (1990-2004) is of 80-95%. This rate of decline would be sufficient to meet CR A2 over three generations (inferred to be 50-60 years), however (a) these data are drawn from a decline in landings, which do not necessarily mean that a decline in abundance has occurred; (b) inference is drawn from C. granulosus and that species is likely to decline more steeply due to greater intrinsic sensitivity; and (c) C. lusitanicus is less common than C. granulosus and hence is/was less likely to be as targeted as C. granulosus. The estimated decline over 14 years (1990-2004) based on ICES landing data is of 80-95%; a decline of 98.36% has been inferred for the 10 year period of 2005-2015; and a decline of 99% is projected over the next 25-35 years (2015-2050). This supports a >70% decline over three generations (50-60 years) in European waters.

habitat:
This shark is found over the outer continental shelves and upper slopes at depths between 300 and 1,400 m, mostly between 300 and 600 m (Compagno et al. 2005, Ebert et al. 2013). It has been taken at 370-610 m in the Northeast Atlantic (Ebert and Stehmann 2013). Little information is available on the biology of this species. Maximum size is about 100 cm total length (TL) (Compagno et al. 2005, Ebert et al. 2013). Males mature at about 75 cm TL and females at 85-95 cm (Ebert et al. 2013). This is an aplacental, live bearing shark, with only one pup per litter (Compagno et al. 2005, Ebert et al. 2013). Size at birth is about 33-36 cm TL (Compagno et al. 2005, Ebert et al. 2013).Centrophorus species are very slow to mature, and have extremely low fecundity and reproductive output, making them intrinsically very vulnerable to population depletion (longevity > 30 years and one pup produced every two years). This species is middle-sized (hardly surpasses one metre in length) and may therefore be at least equally or even more biologically vulnerable to depletion than other Centrophorus species. Its generation length is estimated to be about 25-30 years.

threats:
This shark is of conservation concern because of its limited range, extremely low fecundity, and exposure to deepwater fisheries in the Northeast Atlantic (Compagno et al. 2005, Ebert et al. 2013). It is probably fished in the eastern Atlantic together with other species of the genus Centrophorus by bottom trawls, fixed bottom nets and line gear. It is potentially sensitive in any area where these types of fishery operate within its range.The Portuguese longline fishery, which targets Black Scabbard Fish (Aphanopus carbo) at depths of 800-1,200 m off the coast of Portugal, takes a bycatch of deepwater sharks, including Centrophorus species (ICES 2007). A Spanish longline fishery for Blackspot Seabream (Pagellus bogaraveo) and a bottom trawl fishery off southern Portugal, which targets some deepwater crustaceans, also take a bycatch of deepwater sharks (ICES 2007). In 2006, a new deepwater gillnet fishery was initiated in this area and in waters northwest of Spain (ICES 2007). Off Portugal, the target species of this fishery are deepwater crab (283 tonnes; t) and several deepwater sharks (135 t, plus 31 t of livers and oil; ICES 2007).In the Northeast Atlantic the threat of deepwater fisheries has subsided as effort has decreased over the past decade (Dransfeld et al. 2013, STECF 2014). However, these fisheries should still be monitored in case of future expansion. Other fleets from Spain and other countries are also fishing in this area with both fresh and freezer vessels focusing on other demersal and semipelagic stocks, but little information is available to assess their effect on demersal stocks (Fernández et al. 2005).

conservationAction:
Based on advice from the International Council for the Exploration of the Sea (ICES) to end fishing for deepwater sharks, the European Union (EU) Fisheries Council in 2007 established and began gradual reductions for a Total Allowable Catch (TAC), including Gulper Shark and Leafscale Gulper Shark, but not Lowfin Gulper Shark (C. lusitanicus) (CEC 2012). In 2010, the EU Council added four deepwater shark species to the measure, and set the deepwater shark TAC at zero, starting in 2012 (ICES 2013). In 2013, in response to advice from the International Council for the Exploration of the Sea (ICES), the list of species covered by the deepwater shark TAC was amended to include all species of the genus Centrophorus in the region, thereby closing a loophole for landing Lowfin Gulper Shark. It is recommended that species-specific monitoring of bycatch levels and population trends are carried out, as well as monitoring of fisheries expansion within this species’ range.

redListAssessors:
Guallart, J., Walls, R., Clarke, M., White, W.T. & Compagno, L.J.V.


redListCategoryRationale:
European regional assessment: Endangered (EN)Leafscale Gulper Shark (Centrophorus squamosus) is frequently retained as bycatch in deepwater longline and trawl fisheries in the Northeast Atlantic off Ireland, Spain, Portugal and France. Quantitative catch per unit effort data available for autoline catches in three different areas of the Northeast Atlantic show an 80−90% decline in three years, a 67−77% decline in four years, and a 20−69% decline in a single year. These data represent catches for this species and Portuguese Dogfish (Centroscymnus coelolepis) lumped together. A decline of 73% is projected for the 2000-2099 period. Given the estimated severity of decline, together with the more sensitive life history of the Leafscale Gulper Shark compared to Portuguese Dogfish, and the acute sensitivity of Centrophorus species to exploitation in general, Leafscale Gulper Shark is assessed as Endangered under Criterion A4b in European waters.

range:
This is a widely distributed gulper shark that has a global range. Within the Northeast and Central Atlantic it occurs from Iceland and the Atlantic slope southwards to the Faroe Islands, Canary Islands, Madeira, the Azores and Senegal (Ebert and Stehmann 2013). Although there are a handful of questionable and sporadic records, it is generally considered absent from the Mediterranean Sea. Its depth range is 230-4,000 m.

population:
In the Northeast Atlantic there has been a decreasing trend in biomass for this species in Scottish and Irish deepwater surveys (ICES 2012). Additionally, relative abundance estimates from Scottish surveys suggest an ongoing and significant decline since 1998 (ICES 2013). This species congener, Gulper Shark (C. granulosus), has reportedly declined by 80−95% in the Northeast Atlantic, and so it can be assumed that this species has undergone population decline in the region as well, given the similar life history, range and exposure to fisheries.In the Northeast Atlantic, deepwater shark catches in the mixed trawl fishery off Rockall Trough and Porcupine Bank consisted predominantly of this species and Portuguese Dogfish (Centroscymnus coelolepis). Catches of these two species increased from 302 tonnes (t) in 1991 to 3,284 t in 1996, and then declined to 1,939 t in 1999 (ICES 2000). Although this may suggest population decline, changes in fishing effort were not specifically accounted for, therefore it is possible that fishing effort declined between 1996 and 1999. Landings of these two species in French bottom trawl fisheries increased rapidly from 322−2,939 tonnes between 1990 and 1996 (Girard and Du Buit 1999). Autoline catches in waters west of Scotland showed an 80−90% decline in catch per unit effort (CPUE) over three years from 1997−2000. Although these data are for both Leafscale Gulper Shark and Portuguese Dogfish combined, Centrophorus species have been shown to be acutely sensitive to exploitation in New South Wales fishery independent surveys (Graham et al. 2001). Biomass estimates for the period 2000-2011 (ICES 2012) show an annual proportion of change of 0.986994. This population decline is projected over 100 years, obtaining a 73% decline for the 2000-2099 period. It should also be noted that due to the apparent long lifespan of this species, the recovery of a heavily fished population would likely be very slow, but regional subpopulations of this species may be connected. A recent population genetic study of samples taken from different regions showed low genetic variability, which supports the idea that the species can make long-distance movements along continuous continental slope habitats as well as movements across ocean basins (Veríssimo et al. 2012). 

habitat:
This shark is both demersal and pelagic. Its demersal habitat is on the continental slopes at depths between 230 and 2,400 m, while its pelagic habitat is in the upper 1,250 m of oceanic water column at depths to 4,000 m (Compagno and Niem 1998). It can migrate hundreds of kilometres in several weeks along slope waters (Yano and Tanaka 1986, Rodríguez-Cabello and Sánchez 2014), and there is some evidence that pregnant females segregate from the rest of the population (Severino et al. 2009)This live bearing with yolk sac species produces between two and 10 pups per litter. Size at birth is between 35 and 43 cm total length (TL; Last and Stevens 1994, Cox and Francis 1997, Severino et al. 2009). There is no apparent seasonal reproductive cycle (Girard et al. 2000). In waters off Ireland, sampled individuals of this species provided age estimates of 21−70 years (Clarke et al. 2002), although this study did not validate whether or not otolith rings were formed annually. This suggests that this species attains maturity at a relatively late age. Size at maturity is approximately 100 cm TL in males and around 125 cm TL in females (Girard and Du Buit 1999, Clarke et al. 2001, Severino et al. 2009), while maximum length for both sexes is estimated at 160 cm TL (Compagno and Niem 1998). The species has a maximum age of at least 70 years (Clarke et al. 2002), and its generation length is calculated to be around 50-52.5 years.

threats:
Like other deepwater shark species this shark is taken incidentally in mixed deepwater trawls, mixed longline and gillnet fisheries along continental slopes (Gordon 1999), and was historically exploited commercially. Deepwater longline and trawl fisheries off Ireland, Spain, Portugal and France historically captured large numbers of this species (Iglesias and Paz 1995, Girard and Du Buit 1999, Clarke et al. 2001, ICES 2008), and likely still retain this species as bycatch. As this species is common bycatch in deepwater fisheries, population recovery may be achieved by an overall reduction in demersal fishing effort (ICES 2012) but may take up to several decades to achieve even if all deepwater fishery mortality ceases (OSPAR Commission 2010).

conservationAction:
Based on advice from the International Council for the Exploration of the Sea (ICES) to end fishing for deepwater sharks, the European Union (EU) Fisheries Council in 2007 established and began gradual reductions of Total Allowable Catch (TAC), including Leafscale Gulper Shark. In 2010, the EU Council added four deepwater shark species to the measure, and set the deepwater shark TAC at zero, starting in 2012. In 2013, in response to ICES advice, the list of species covered by the deepwater shark TAC was amended to include all species of the genus Centrophorus (Centrophorus spp.), thereby closing a loophole for landing Lowfin Gulper Shark (Centrophorus lusitanicus). Detailed quantitative information on CPUE for Leafscale Gulper Shark throughout its range is required to assess whether CPUE is declining. Monitoring and management of harvest trends should be undertaken.

useAndTrade:
The species was historically exploited commercially.

redListAssessors:
Guallart, J., Walls, R.H.L. & White, W.T.


taxonomicNotes:
Taxonomy of the genus Centrophorus has been much controverted during the last fifty years. Part of the confusion has been focused on two species with sessile dermic denticles (thus different from C. squamosus) whose most conspicuous anatomic differences are maximum size and size at sexual maturity. The species assessed here is to be considered the “smaller” species, and has been recently reported under the name of C. granulosus or C. uyato. Taxonomic confusion comes from a long history of mistakes in the literature but also from a problem of nomenclature. A recent review by White et al. (2013) included a re-description and the settlement of a neotype of the “larger species” as C. granulosus (Bloch and Schneider 1801). Nomenclature status of this species is pending a paper in preparation that is based on classic taxonomy, review of nomenclature and genetic data, and that will also include a re-description of the species (Guallart et al. 2013, Veríssimo et al. 2014).At present this assessment is presented under the name C. uyato (Rafinesque 1810) pending this review. It must be noted that this species is assumed not to fit the description made as Squalus uyato by Rafinesque (1810) but its first descriptions of reference are those made as Spinax uyatus by Bonaparte (1834) and Müller and Henle (1839) as C. granulosus.

redListCategoryRationale:
European regional assessment: Vulnerable (VU)A relatively common, sometimes very abundant, deepwater dogfish with a widespread global range, although actual knowledge of its range still depends on definite resolution of taxonomy of the genus. It inhabits the upper continental slopes and outer continental shelf area. The “larger” species, Gulper Shark (Centrophorus granulosus) is believed to have the lowest reproductive potential of all elasmobranch species; its reproductive biology is characterized by a late onset of maturity (12 to 16 years in females), only one pup per litter, and a two-year gestation period with occasional resting periods. This makes it extremely sensitive to overexploitation and population depletion. It is expected that while the life history of the “smaller” species, assessed here as Little Gulper Shark (C. uyato), is likely to be similar, it is perhaps less slow given the smaller size and therefore faster expected rate of population increase.Based on the geographic range of Gulper Shark, it is suspected that this species is similarly relatively common in the Mediterranean Sea, but the combination of localized depletion subsequent to brief targeted fishing efforts (as inferred from Gulper Shark declines) and the species’ inherent sensitivity to exploitation even in moderate numbers through bycatch, leads to the suspicion of regional declines. In European waters, the species is suspected to have declined by at least 30% over the three-generation period. Therefore, Little Gulper Shark is assessed as Vulnerable under criterion A2b inferred from declines of its congener, and based on the declining status of the other similar-sized, Europe-based member of the genus Centrophorus, Lowfin Gulper Shark (C. lusitanicus), which is assessed for the region as Vulnerable as well.There is an urgent call for further data collection in European waters, and monitoring of the extent to which this species is affected by bycatch. The taxonomic issues relating to this species need to be resolved (see Taxonomic Notes) and the gulper sharks (Centrophorus spp.) examined to determine species-specific trends moving forward.

range:
This species occurs in the Northeast Atlantic off France, Spain (including the Canary Islands), and Portugal (including Madeira). In the Mediterranean Sea, it occurs in waters off Albania, Algeria, Cyprus, France, Greece, Italy, Israel, Lebanon, Morocco, Spain, Syria, Tunisia and Turkey. It is also present in the Marmara Sea, although absent from the Black Sea (Boutan 1926, Maurin 1968, Jardas 1984, Fischer et al. 1987, Papakonstantinou 1988, Ungaro et al. 1994, Baino et al. 2001, Kabaskal 2002). The exact range of this species requires further investigation as these areas are inferred from the “large” species of the complex from which it has been split, Gulper Shark (Centrophorus granulosus). Its depth range is 100-1,400 m.

population:
The determination of the range and population of this species is hindered by unresolved taxonomic issues (see Taxonomic Notes). No information is available on relationships between Mediterranean Sea and Atlantic subpopulations of Little Gulper Shark (Centrophorus uyato); however, like most Mediterranean Sea deepwater species, some degree of isolation is expected due to the barrier of the Straits of Gibraltar. Northeast AtlanticFor this region, landings data were obtained from ICES (2006) for its congener, Gulper Shark, for the Portuguese coast (main range). These show a strong decline in catch from about 1,000 t in 1990 to less than 100 t in 2004. As a crude index of abundance, a delury depletion model was implemented, assuming constant effort over the time series. The results of this suggest that the stock has declined by between 80 and 95% of its initial size when fishing began. This is based on two assumptions of effort. This assumes that recruitment does not occur. Though this is clearly not true, the extreme low fecundity and reproductive output suggests that effect of recruitment is very low indeed. Recruitment of Little Gulper Shark is expected to be higher than that of Gulper Shark, but with such steep declines it is precautionary to suspect a decline in this species in the Northeast Atlantic as well, albeit to a suspected lesser extent.Mediterranean SeaAnalysis of the International Trawl Survey in the Mediterranean (MEDITS) data from 1994 to 1999 show a low frequency of occurrence (only 2% of total hauls), for Gulper Shark (C. granulosus), which actually refers to Little Gulper Shark. Its overall biomass was estimated to be 2.9 kg per km2, with a presence throughout the Mediterranean Sea, though more abundant in the western central and western area (5.5 and 2.7 kg per km2 respectively). The depth range of the biomass index show values of less than 0.1 from 50 to 100 m of depth and between one and > 10 kg per km2 from 200 to 800 m. Baino et al. (2001) give a standing stock biomass estimate of only 1,528 tonnes (t) (3%) for the west, north and east Mediterranean Sea from zero to 800 m depth. These data have been used to argue that it is very rare in the Mediterranean Sea. The MEDITS program surveys waters up to 800 m in depth. However, there is evidence that the species tends to aggregate near rocky areas in submarine canyons of the slope, where trawling is hardly possible. Thus, data from trawling surveys are not representative of actual abundance.This species may have been locally very abundant in parts of the Mediterranean Sea. Catches of several tens or even hundreds of specimens in a journey from a single fishing vessel using bottom longlines or bottom gillnets have not been rare in the Balearic Sea (western Mediterranean Sea) (Guallart 1998). Population trends are not well known in Mediterranean and European waters, though rapid decreases in local abundance in areas where intensive fishing pressure has occurred have been estimated. A decrease in the area of occupancy is also suspected due to present fishing pressure in the depth range this species inhabits.Little Gulper Shark is suspected to have declined to at least 30% over the last three generations in European waters.

habitat:
Little Gulper Shark is a medium-sized deepwater species inhabiting the upper continental slopes and outer continental shelves. It is usually demersal or benthopelagic, at depths from 100 to 1,490 m (Mediterranean Sea), with most records between 300 and 800 m (Compagno 1984, Gilat and Gelman 1984, Guallart 1998, Baino et al. 2001). This shark is thought to have schooling habits (Maurin 1962, Compagno 1984, Gilat and Gelman 1984) because of the abundance in some catches or by the simultaneous presence of several individuals in baited cameras set over the bottom. It may also aggregate in particular areas of the slope, particularly in the margins of submarine canyons (Guallart 1998). Some evidence suggests that individuals present in the lower half of the depth range are mainly juveniles (Gilat and Gelman 1984, Guallart 1998). For the “large” species, Gulper Shark, age at maturity is estimated at 12 to 16 years in females and seven to eight years in males (Guallart 1998), with earlier estimates of four to five years for both males and females (Rizzo et al. 1993). Estimates of female size at maturity are 89 to 102 cm total length (TL), 93 cm when half mature (Guallart 1998) and earlier estimates range between 70 and 95 cm TL (Capapé 1985, Fischer et al. 1987). Mature male size estimates are 79 to 85 cm TL (80 cm TL at half maturity) (Guallart 1998) and 70 to 80 cm TL (Capapé 1985, Fischer et al. 1987, Rizzo et al. 1995). Maximum recorded size is about 120 cm TL (Fischer et al. 1987, Guallart 1998). Size at birth ranges from 30 to 46 cm TL (Fischer et al. 1987, Guallart and Vicent 2001) and longevity is over 30 years (Guallart 1998). The average reproductive age of Gulper Shark is unknown. It can be assumed that these estimates are slightly lower for Little Gulper Shark.Gulper Shark is a lecithotrophic, aplacental viviparous species (Ranzi 1932, Guallart and Vicent 2001). It has an extremely low reproductive rate, with only one pup per litter (Tortonese 1956, Capapé 1985, Guallart 1998), a gestation period of about two years, and occasional resting periods between pregnancies (Guallart 1998, Guallart and Vicent 2007). Its generation length is estimated in 16-20 years, and therefore its three-generation period is estimated to be about 50 to 60 years. This probably makes it the elasmobranch species with the lowest reproductive potential. Again, these values are likely to be slightly lower for Little Gulper Shark.

threats:
This is a widespread species that is reportedly heavily fished as bycatch in the Northeast Atlantic and the Mediterranean Sea. In the Northeast Atlantic it is caught with bottom trawls, long lines, fixed bottom nets, hook and line, and pelagic trawls (Ebert et al. 2013). Within the Mediterranean Sea, one of the main threats is development of target fisheries with longlines and gillnets in areas on the continental slope, where this species tends to aggregate. However, the global trend of fisheries expanding into deeper unexploited grounds may not occur in the Mediterranean Sea, due to the relatively low level of biomass found in deeper waters of this sea, and as the fishing fleets are composed mainly of artisanal vessels. Local factors such as the fleet characteristics, the distance from the coast to suitable substrates, and the perceived appreciation of the flesh and other byproducts of this species may, in many countries, limit the potential for a targeted fishery to develop. A number of authors have commented on the economic potential to develop a targeted fishery for gulper sharks (e.g., Boutan 1926 in Algeria, Rancurel 1983 in France, Gilat and Gelman 1984 in Israel), however there is no information regarding potential developments at present. Given the inferred low reproductive potential of this species, it is likely highly sensitive to overexploitation and population depletion under even moderate fishing pressure. Therefore extreme caution should be exercised before the development of any targeted fishery. Within the Mediterranean Sea this species is also caught as bycatch by bottom longlines, bottom gillnets, and bottom trawls targeting Red Shrimp (Aristeus antennatus) (Fischer et al. 1987). Further information on the catch rates of this species by this trawling fleet are required before the effect that this has on the population can truly be assessed. 

conservationAction:
The General Fisheries Commission for the Mediterranean (GFCM), the main intergovernmental decision-making body on fishery management in the Mediterranean Sea, banned bottom trawling below depths of 1,000 m in the Mediterranean Sea in February 2005 and this began in September 2005. The measure was adopted by consensus by all members of the GFCM, which include: Albania, Algeria, Bulgaria, Croatia, Cyprus, EC, Egypt, France, Greece, Israel, Italy, Japan, Lebanon, Libya, Malta, Montenegro, Morocco, Romania, Slovenia, Serbia, Spain, Syria, Tunisia, and Turkey. This decision may protect part of this species’ population from fishing pressure, particularly juveniles that seem to occupy the deepest part of its depth range.Based on the International Council for the Exploration of the Sea’s (ICES) advice to end fishing for deepwater sharks, the European Union (EU) Fisheries Council in 2007 established and began gradual reductions for a Total Allowable Catch (TAC) of a group of deepwater sharks including Little Gulper Shark. In 2010, the EU Council added four additional deepwater shark species to the measure, and set the deepwater shark TAC at zero, starting in 2012. In 2013, in response to ICES advice, the list of species covered by the deepwater shark TAC was amended to include all species of the genus Centrophorus.There is an urgent call for further data collection in European waters, and monitoring of the extent to which this species is affected by bycatch. The taxonomic issues relating to this species need to be resolved (see Taxonomic Notes) and the gulper sharks (Centrophorus spp.) examined to determine species-specific trends moving forward.

useAndTrade:
Fisheries targeted this species towards the end of the 20th century in the Balaeric Sea, causing rapid, steep declines. One example of these target fisheries was an alternative artisanal bottom longline fishery that developed in periods when other target species had declined. Abundance (catches of about 50-80 specimens or 300-400 kg per ship and journey) and price of flesh was comparable to that of the original target species. However, catches of Little Gulper Shark decreased significantly within a matter of weeks. An increase in abundance within these depleted areas took place after several months, presumably by migration from other unexploited areas. In another example, a semi-industrial fishery was carried out for several years. One ship made trips of several days covering wide areas unexploited for this species. Catches reached up to 900 specimens (about 5,000 kg) (Guallart 1998). As well as this example, there are now still Lebanese and Syrian deepwater longline fisheries, and likely similar fisheries in other areas of the Mediterranean Sea, that target this (and other) sharks. Flesh, livers and tails (as lower quality shark fins) are marketed. The flesh is relatively highly valued and marketed, and less commonly, its large squalene-rich livers. 


redListCategoryRationale:
European regional assessment: Endangered (EN) Birdbeak Dogfish (Deania calcea) is taken as bycatch by deepwater trawl, longline and gillnet fisheries and is usually discarded. Prior to European Union catch limits in 2010, this species was one of the most common commercially captured deepwater sharks in European waters. This deepwater shark has very low productivity; females attain maturity at ~ 25 years, longevity is at least 35 years, and generation span is around 30 years. There has been an overall historical decline in abundance since the 1970s of around 89%, but catch rates in Scottish surveys increased between 1998 and 2004, and more recent survey data from Scotland suggests an increase in relative abundance, although these overall catch rates are much lower when compared to surveys conducted in the 1970s. Birdbeak Dogfish has therefore undergone a decline of 89% for the 1970-2012 period, and it is projected to increase its population at a rate of around 3% per year, therefore resulting in an overall 55% decline for the three-generation period (90 years). Thus, the species is assessed as Endangered European waters under Criterion A4d. Catches and landings should be monitored carefully to ensure this species does not become threatened. The efficacy of current management measures should also be evaluated.

range:
In the Northeast Atlantic, this species occurs from Iceland along Atlantic slope to the Faroe Islands, Scotland, Ireland, France, Spain, Portugal, Morocco, Azores, Madeira and Mauritania, but it is absent from the Mediterranean Sea (Ebert and Stehmann 2013).

population:
This is one of the most abundant mid-slope species of deepwater dogfish in the Northeast Atlantic. Bottom trawl surveys conducted in Porcupine Bank, off the coast of Ireland, have reported increasing biomass and numbers per haul from 2012−2013 (Ruiz-Pico et al. 2014). Estimates of relative abundance on the Scottish slope using a General Additive Model also showed a recent increase (ICES 2014). However, the catch of individuals smaller than 65 cm has declined since 2001 with no specimens recorded in the year 2013 (Ruiz-Pico et al. 2014). Additionally, while these recent surveys suggest a relative increase, overall catch rates in these surveys were only 11% of historical surveys conducted in the 1970s. While these surveys cannot be directly compared because they used different gear and vessels and fished different depth ranges, they do indicate an overall decline from historical levels, although the magnitude of the decline is uncertain.Birdbeak Dogfish has therefore undergone a decline of 89% from 1970 to 2012, and in the absence of direct fishing as a result of the EU ban, an increase of around 3% per year is suspected, resulting into a 55% reduction of the population of the species for the three-generation period (90 years).

habitat:
This species occurs on or near the bottom over outer continental slopes and insular shelves at depths of 60–1,490 m, but is most common from 750–800 m (Ebert and Stehmann 2013). It may occur in large groups and appears to segregate by size, sex and maturity status, where immature specimens are distributed deeper and mature pregnant females occur in shallower waters (Moura et al. 2014). Their diet suggests that they feed at some height above the bottom (Mauchline and Gordon 1983, Yano 1991, Ebert et al. 1992, Daley et al. 2002), which may reduce their susceptibility to demersal trawl gear. In this live bearing species, embryos rely solely on yolk for nutrition. Gestation may take up to two years and litters range from one to 17 pups with an average of seven. Size at birth is 25-34 cm total length (TL). Length at maturity is 81−94 cm and 99−106 cm TL for males and females, respectively (Clarke 2000, Clarke et al. 2002, Paiva et al. 2011, Ebert and Stehmann 2013). Estimated age at maturity is 17 years for males and 25 years for females. The maximum recorded size is 122 cm TL (Ebert and Stehmann 2013) and estimated longevity is ~ 35 years (Clarke et al. 2002). Its generation length is ~ 30 years.

threats:
This species is caught by trawl, hook and gillnet fisheries in the Northeast Atlantic and has been directly targeted for its liver oil and flesh (Bakes et al.1995). Small catch volumes have been reported over the past decade, with an average of 119 tonnes reported between 2000 and 2009 by the Food and Agricultural Organisation of the United Nations (FAO). During this period, most reported landings of this species were made by Portugal (averaging 74 tonnes), followed by Spain (averaging 26 tonnes) and the United Kingdom (average 17 tonnes). These numbers likely underestimate total landings, as this species is included in uncategorized landings with other mixed deepwater squaloid species. It has also been reported as bycatch in French deepwater fisheries and Spanish longlines and trawls, where it is generally discarded (Connolly and Kelly 1996, Pineiro et al. 1998, Allain et al. 2003). The larger females tend to be more susceptible to capture on longline hooks, rather than in trawl nets (Clarke et al. 2005).

conservationAction:
In 2013, the EU banned removal of shark fins on board vessels (CEC 2013), in line with advice from the International Union for the Conservation of Nature’s Shark Specialist Group and other shark fishery experts, in order to enhance enforcement of the 2003 EU ban on shark finning (CEC 2003) and facilitate improved shark fishery data collection.Based on advice from the International Council for the Exploration of the Sea to end fishing for deepwater sharks, the European Union Fisheries Council established a TAC (Total Allowable Catch) for this species in 2007 (CEC 2012). This TAC was gradually reduced and in 2010 it was set at zero. In 2011, the allowable bycatch was reduced from 10% to 3% of the 2009 TAC and in 2012 it was further reduced to zero (ICES 2013). In the future, bycatch should be carefully monitored as this species is sensitive to exploitation like other deepwater sharks (Kyne and Simpfendorfer 2007). Research should be conducted on the population size and trend of the species.

useAndTrade:
This species is caught for its liver oil and flesh. The livers are high in squalene comprising about 70% by weight (Bakes et al. 1995). Catches in Australia have been increasing in the last few years with relaxation of mercury laws and fishers looking for non-quota species in the South East Trawl Fishery.


taxonomicNotes:
Bigelow and Schroeder (1957) synonymized this species with Deania calcea (as its synonym D. eglantina). Cadenat and Blache (1981) named a new species D. mauli, from Madeira, however D. mauli was later recognized as D. hystricosa by Garman (1906, 1913) and was tentatively synonymized with D. hystricosa by Compagno (1984). Compagno (1984) recognizes this species as separate from D. calcea. The characters that distinguish D. hystricosa from D. calcea need to be examined in more detail.

redListCategoryRationale:
European regional assessment: Data DeficientThe Rough Longnose Dogfish (Deania hystricosa) is a little known medium-sized (of at least 111 cm total length) benthic, and probably epibenthic, deepwater shark. It occurs at depths of 471–1,300 m on upper and middle continental and insular slopes. This dogfish is taken by deepwater longline fisheries off Madeira and the Canary Islands where it is used for its meat and liver oil. The lower portions of the species’ depth distribution may offer refuge from fishing pressure. At present, no data are available to infer population trends for this species so it cannot be assessed beyond Data Deficient. Furthermore, characters that distinguish the Rough Longnose Dogfish from Shovelnose Spiny Dogfish (Deania calcea) need to be examined in greater detail. Like other deepwater sharks, this species may be biologically vulnerable to population depletion. The bycatch levels in fisheries should be determined and monitored, especially as fisheries expand into deeper depths across the species’ range.

range:
This species has a patchy distribution in the Northeast and Eastern Central Atlantic. Records show that it is found southwest of the British Isles, in the Bay of Biscay and Galician waters (northwest Spain), the Azores, Madeira, and Canary Islands (Bañón et al. 2010, Ebert and Stehmann 2013). The depth range is 471–1,300 m. It is also found in the Pacific Ocean and the southern Atlantic.

population:
In Madeira the species is common and was captured with bottom long-lines during two research cruises in 2004 and 2005 (M. Freitas and M. Biscoito pers. comm. 2015).Nothing more is known of the population size or trends in the Northeast Atlantic region for this species, except that, as with Arrowhead Dogfish (Deania profundorum), it is rarely reported by deepwater fisheries operating within its range, and is therefore probably very rare.

habitat:
This little-known benthic, and probably epibenthic, dogfish is found on the upper and middle continental and insular slopes at depths of 471–1,300 m (Ebert and Stehmann 2013). Adults attain a maximum total length (TL) of 111 cm (Ebert and Stehmann 2013). The males are reported to reach sexual maturity at 81–84 cm TL while females mature at 92–106 cm TL. The size at birth is uncertain. This dogfish is live-bearing, in that the young are born alive rather via egg, with yolk-only nutrition. The litter size is not known, but a female found with 12 large ovarian eggs suggests moderate-sized litters (Ebert and Stehmann 2013). 

threats:
This species is caught minimally with deep-set vertical longlines off Madeira, Porto Santo, Seine and Unicorn seamounts and the Canary Islands, where it is used for liver oil and meat (Ebert and Stehmann 2013).The Azores deepwater fishery is a multi-species and multi-gear fishery (ICES 2007). It is predominantly small-scale (vessels <12 m; 90% of the total fleet) using traditional bottom longline and several types of hand lines operating down to 1,000 m depth, but mainly 200–600 m (ICES 2007). The Azorean longline fishery has expanded to more offshore seamounts over the last few years due to intensive fishing or overexploitation of important commercial demersal/deepwater stocks (ICES 2013). Landings of demersal/deepwater sharks were very low during these years as a result of quota restrictions (Pinho 2013). While target fisheries for elasmobranchs do not exist in this area, discards are expected to increase, particularly from longliners, because quota and local area restrictions on fishing are being introduced in International Council for the Exploration of the Sea (ICES) Subdivision Xa2 (Azores Economic Exclusive Zone; ICES 2013).This species is reported as bycatch in ICES Subarea XII (North of Azores) along with other Deania species, but there is no way of confirming the percent composition Rough Longnose Dogfish makes up of the overall bycatch of this genus (Ebert and Stehmann 2013). In the North Atlantic, this species and the Arrowhead Dogfish appear to be far less abundant than the more common Shovelnose Spiny Dogfish (Deania calcea).

conservationAction:
Prior to 2010, a combined Total Allowable Catch (TAC) was set for a group of deepwater sharks in European Commission waters. While the main group did not include Rough Longnose Dogfish, this species was included in this measure specifically for ICES Subarea XII (ICES 2013). In 2010, TACs in all areas were reduced to zero for this group, with an allowance for bycatch of 10% of the 2009 TAC. For 2011, the bycatch allowance was reduced to 3% of that in 2009, and in 2012 no allowance for bycatch was permitted. This remained the status quo in 2013 (ICES 2013). The use of fixed gillnets at depths of over 200 m has been banned in the archipelagos of the Azores, Madeira and the Canary Islands (ICES 2007). Further research is required to determine the population size and trends while harvesting trends also need to be monitored.

useAndTrade:
This species is caught minimally with deep-set vertical longlines off Madeira, Porto Santo, Seine and Unicorn seamounts and the Canary Islands, where it is used for liver oil and meat (Ebert and Stehmann 2013). 

redListAssessors:
Ebert, D.A., McCormack, C., Freitas, M., Conceicao Biscoito, M.J., Francis, M.P., Tanaka, S., Ishihara, H., Holtzhausen, H. & Stewart, A.


taxonomicNotes:
There are at least two common birdbeaked dogfish known from Namibian waters with two less common species rarely taken in very deepwater. A taxonomic review of this group is required to properly identify the species of this genus.

redListCategoryRationale:
European regional assessment: Data Deficient (DD)The Arrowhead Dogfish (Deania profundorum) is a moderately sized (up to 97 cm total length) dogfish found on or near the bottom of the upper continental and insular slopes at depths of 275–1,785 m. It is often found in large aggregations, which possibly increases the threat of overfishing where fisheries occur. There is little information on the catch of this species, but deepwater fisheries operate over much of its range within Northeast and Eastern Central Atlantic regions (e.g., Canary Islands and the Azores). This species is taken on longlines off the Canary Islands and used for liver oil and meat. Incidental bycatch is likely discarded, particularly around the Azores where zero Total Allowable Catch (TAC) measures are in place. At this stage, there are insufficient reliable catch or landings data, or life history information, available for this species with which to deduce population trajectories, so an assessment of Data Deficient is given for the European region. 

range:
Within the European region, this species is found in the Eastern Central Atlantic. It has been recorded in the Canary Islands, Azores, and off the Western Sahara (Ebert and Stehmann 2013). Coelho and Erzini (2006) reported one individual off southwest Portugal, though this is uncommon and the northernmost the species has ever been recorded. The depth range is 275–1,785 m.

population:
Very little information is available on the population size or trend throughout this species’ range. Before 2009, Arrowhead Dogfish abundance was recorded together with Shovelnose Spiny Dogfish (Deania calcea) in International Council of the Exploration of the Sea (ICES) reporting. When the Arrowhead Dogfish was described within ICES Subdivision VIIIc (southern Bay of Biscay) and IXa (eastern Portuguese waters) in 2009, they began recording them separately (Sanjuan et al. 2012). Reports from 2009 to 2012 show an increase in the catch of Shovelnose Spiny Dogfish in 2012, after being absent in the two previous years, whereas Arrowhead Dogfish remained steady in the catches from 2010 in both divisions (ICES 2013).The population trends are unknown across the entire North Atlantic, but are apparently stable for ICES Subdivisions VIIIc and IXa (ICES 2013).

habitat:
This deepwater dogfish is found on or near the bottom of continental and insular slopes at depths of 275–1,785 m. Observations suggest they may be more common at the deeper end of their bathymetric range.The maximum total length (TL) reported is about 97 cm, but most known individuals are smaller. Adult males are 43–67 cm TL and adult females are 62–80 cm TL. Size at birth is at least 31 cm TL (Ebert and Stehmann 2013). The reproductive mode is live-bearing with yolk-only nutrition. The probable litter size is five to seven pups judging from fertilised eggs in the uteri of females (Compagno et al. 1989). The species sometimes occurs in huge aggregations or schools (Ebert and Stehmann 2013).  

threats:
This species is caught incidentally by deepwater fisheries operating over the majority of its European range. It is caught on longlines off the Canary Islands and used for liver oil and meat (Ebert and Stehmann 2013). The Azorean longline fishery has recently expanded to more offshore seamounts due to intensive fishing or overexploitation of important commercial demersal/deepwater stocks (ICES 2013). Landings of demersal/deepwater sharks were very low during these years as a result of quota restrictions (Pinho 2013). While target fisheries for elasmobranchs do not exist in this area, discards are expected to increase, particularly from longliners, because of quota and local area restrictions to fishing being introduced in ICES Subdivision Xa2 (Azores Exclusive Economic Zone; ICES 2013).This species is present in ICES Subarea XII (north of Azores) and reported as bycatch along with other Deania species; however, there is no way of confirming the percentage composition Arrowhead Dogfish makes up of the overall bycatch of this genus (Ebert and Stehmann 2013). This species and Rough Longnose Dogfish (Deania hystricosa) appear far less abundant than the more common Shovelnose Spiny Dogfish in the North Atlantic.It is likely that landings reported as Shovelnose Spiny Dogfish include other species in the same genus (Arrowhead Dogfish and Rough Longnose Dogfish), particularly in Portuguese landings from the Azores (Pinho 2010). Misidentification problems were detected in mainland Portuguese landing ports where two different Deania species are observed in catches: Shovelnose Spiny Dogfish and Arrowhead Dogfish. Similarly, reports of Lowfin Gulper Shark (Centrophorus lusitanicus) in Portuguese landings data from 2009-2012 are believed to refer to misidentified species, including Shovelnose Spiny Dogfish and Arrowhead Dogfish (ICES 2013).

conservationAction:
Prior to 2010, a combined Total Allowable Catch (TAC) was set for a group of deepwater sharks in European Commission waters. While the main group did not include Arrowhead Dogfish, this species (along with Rough Longnose Dogfish) was included in this measure specifically for ICES Subarea XII (ICES 2013).In 2010, TACs in all areas were reduced to zero for this group, with an allowance for bycatch of 10% of TACs in 2009. For 2011, the bycatch allowance was reduced to 3% of that in 2009, and in 2012 no allowance for bycatch was permitted. This remained the status quo in 2013 (ICES 2013).The use of fixed gillnets at depths of over 200 m has been banned in the archipelagos of the Azores, Madeira and the Canary Islands (ICES 2007).Further research is required to determine the population size and trends of this species.

useAndTrade:
This species is caught incidentally by deepwater fisheries operating over the majority of its European range. It is caught on longlines off the Canary Islands and used for liver oil and meat (Ebert and Stehmann 2013). The Azorean longline fishery has recently expanded to more offshore seamounts due to intensive fishing or overexploitation of important commercial demersal/deepwater stocks (ICES 2013).

redListAssessors:
Ebert, D.A., McCormack, C. & Samiengo, B.


redListCategoryRationale:
European regional assessment: Endangered (EN)Kitefin Shark (Dalatias licha) is a medium-sized, patchily distributed, deepwater species, usually found at depths of 37−1,800 m. It is taken as bycatch in deepwater longline, bottom trawl and gillnet fisheries in the Northeast Atlantic and the Mediterranean Sea. In the Northeast Atlantic, a 94% decline in catches was observed when historical data collected by the United Kingdom Ministry of Agriculture, Fisheries and Food was compared to more recent Scottish trawl surveys. However, the potential for misidentification and the location of recent Scottish trawl surveys suggest that these data should be interpreted with caution. In addition to being obtained as bycatch, target handline and gillnet fisheries existed for this species in the Azores in the 1970s. Landings in this fishery increased rapidly to 896 tonnes in 1991 and then decreased steadily to < 46 tonnes from 1998 onwards. The life history characteristics of this species, such as slow growth and relatively large size at maturity, make it sensitive to rapid depletion, as evidenced by the catch declines in the targeted fishery. The species has experienced a decline of 62% is European waters for the 1972-2059 period (87 years, three generations), and a reduction of 52% is projected for the 2015-2102 period (87 years, three generations) into the future. Therefore, it qualifies as Endangered under Criteria A3d+4d.

range:
Within the Northeast Atlantic this species occurs on the Atlantic slope of the British Isles (with occasional records from the continental shelf, including the North Sea and Celtic Sea), to Spain and Portugal, including the Azores and Madeira Islands, and the Mid-Atlantic Ridge (McEachran and Branstetter 1984, Ebert and Stehmann 2013). It also occurs in the western Mediterranean Sea (Tortonese 1956, Barrull and Mate 2002, Serena 2005) and there have been some isolated observations in the eastern Mediterranean Sea (Gilat and Gelman 1984). Its depth limit is 37 - 1,800 m.

population:
No information is currently available on population size or structure, however this species is thought to exhibit patchy distribution. There is probably little or no exchange between subpopulations separated by depth or occurring in different water bodies, which are considered to form distinct regional subpopulations (Compagno and Cook 2005). The overall trend in European waters for this species seems to be of a general decrease.Northeast AtlanticThis subpopulation size or structure is unknown in the Northeast Atlantic, however, for the purposes of stock assessment and management, the Azores/Mid-Atlantic Ridge subpopulation is considered to be separate from the Northeast Atlantic Slope subpopulation (ICES 2006, 2013). However, the species seems to be more abundant in the south area of the Mid-Atlantic Ridge International Council for the Exploration of the Sea (ICES; Area X), and is less frequently recorded elsewhere in the Northeast Atlantic. Beginning in the early 1970s this species was targeted by handline and gillnet fisheries in the Azores, and landings increased rapidly to over 947 tonnes (t) in 1981. From 1981 to 1991 landings fluctuated considerably, following market fluctuations, and peaked at 937 t in 1984 and 896 t in 1991 (ICES 2006, 2013). After 1991, reported landings declined linearly until the fishery was closed at the end of the 1990s due to stock collapse. The stock has remained collapsed in the Azores region with landings ranging from zero to two tonnes between 2010 and 2012 (ICES 2006, 2013). Stock assessments of the targeted Azores fishery for this species were made during the 1980s (da Silva 1987). The stock was considered intensively exploited with the average observed total catches (809 t) close to the estimated maximum sustainable yield (MSY=933 t). During the Development of Elasmobranch Assessments (DELASS) project, the stock was considered depleted based on the probability of the biomass in 2001 being less than the biomass that could sustain maximum sustainable yield (BMSY; Heessen 2003). Preliminary assessment results suggest that the stock may be depleted to about 50% of virgin biomass. However, further analysis is required, particularly analysing the effect of liver oil prices on the fishery. Although targeted fisheries have ceased, this species is still bycatch in various deepwater fisheries, with total bycatch landings of around 47 t reported across the Northeast Atlantic ICES area in 2005 (ICES 2006). In mainland Portugal, bycatch landings have been recorded since 1988, with 282 t in 2000 and 119 t in 2003 (ICES 2006, 2013). These landings reached zero tonnes in 2010 and have not increased since. In the Azores, landings of < 15 t were reported from 2004–2005 (Pinho 2006). For the Northeast Atlantic slope subpopulation, a comparison between recent Scottish trawl surveys and United Kingdom Ministry of Agriculture, Fisheries and Food (MAFF) surveys in the 1970s showed a 94% observed decline in catch rate. However, this value must be treated with caution as it is likely that other species were mistakenly identified as this species in the initial 1970s survey (Jones et al. 2005). Furthermore, the Scottish trawl surveys took place at the limit of this species’ geographical range, which may explain the observed low catch rates. Considering a 50% decline for the 1972-2001 period based on the above DELASS data, and if an exponential decline is assumed, the annual proportional change would be 0.9764. Therefore, the reduction for the time period 1972-2059 (87 years, three generations) is 87%. When projecting this decline into the future (2015-2102, three generations), a 64% decline is estimated. MediterraneanIn the Mediterranean, the range of this species appears to be confined to the western and central basins and biomass seems to be very low (Baino et al. 2001). The “Gruppo Nazionale Dermersali” (GRUND) experimental trawl surveys carried out on the continental and upper slopes of the central Mediterranean Sea suggest a positive trend in catches of this species between 1985 and 1998 although the dataset was small; only 1.9 specimens were obtained on average per hour over 12 years of surveys (Relini et al. 2000). This species was present in < 2% of bottom trawls across the Mediterranean Sea (Relini et al. 2000). A bottom trawl fishery for Red Shrimp (Aristeus antennatus) operating in the Gulf of Valencia collected data between 1988 and 1989 on the frequency of catches for this species. It was found to be present in 28.6% of trawls carried out at 450–675 m depth, with a mean abundance of 0.06 specimens per hour of trawling (Guallart 1990). During exploratory surveys to collect data of the exploited and virgin stocks of deep-sea Red Shrimp (DESEAS project), this shark species was caught in all three areas of the study (the Balearic area, the western Ionian and the eastern Ionian). Abundance decreased with depth in the Balearic area and the species was found to be more abundant between 1,000 and 1,499 m in the western Ionian and was present at shallower depths in the eastern Ionian (Sion et al. 2004).In the Mediterranean, considering a 15% decline for the 1972-2004 GRUND data, and if an exponential decline is assumed, the annual proportional change would be 0.9949. Therefore, the reduction for the time period 1972-2059 (87 years, three generations) is 36%. When projecting this decline into the future (2015, 2102, three generation), a decline of 36% is also estimated.Assuming that the proportion of the population present in the Mediterranean and in the Northeast Atlantic is roughly equal, an overall reduction of 62% is calculated for European waters for the 1972-2059 period (87 years, three generations). A reduction of 52% is projected for the 2015-2102 period (87 years, three generations) into the future.

habitat:
This benthic to mesopelagic deepwater shark species is found on continental and insular shelves and slopes in temperate to tropical waters from 37 m down to 1,800 m depth, but primarily from 300–600 m (Compagno 1984, McEachran and Branstetter 1984, Compagno et al. 2005, Ebert and Stehmann 2013). Within the western Mediterranean it occurs at depths of up to 1,800 m (Stefanescu et al. 1992), in the Tyrrhenian Sea it is present between 200-800 m (Baino et al. 2001) and in the Adriatic Sea it was found at depths down to 900 m (Ungaro et al. 2001).This species is live bearing with yolk sac and reproduction is known to occur throughout the year, with greater activity during the summer and autumnal months (Bini 1976, Tortonese 1956). This species can produce three to 16 pups per litter (Lo Bianco 1909, Bauchot 1987, Notarbartolo di Sciara and Bianchi 1998, Ebert and Stehmann 2013), but typically produces six to eight pups per litter (Bini 1976, Tortonese 1956). Size at birth is reported to be ~ 30 cm total length (TL; Lo Bianco 1909, McEachran and Branstetter 1984, Bauchot 1987). Size at maturity is between 77–121 cm TL and 117–159 cm TL for males and females, respectively (Bauchot 1987). This species reaches a reported maximum size of 180 cm TL, although most individuals are 120 cm TL (Bauchot 1987).The species has a maximum age of 32-36 years, and its age at maturity is 15.5-21.5 years (Irvine et al. 2012). Its generation length is estimated to be 28.75 years.

threats:
Northeast AtlanticThis species has been reported in longline and gillnet fisheries targeting mixed deep-water sharks west of the British Isles and off the Portuguese mainland (ICES 2006). Recent emergency measures by the European Commission and Northeast Atlantic Fisheries Commission have closed these deepwater gillnet fisheries. This species is apparently also caught west of the British Isles by mixed deepwater trawl fisheries, volumes are unknown as landings statistics are not species-specific, but they are likely to be low. In addition, while the United Kingdom and Ireland have officially reported landings of this species, these individuals have likely been misidentified, and are more likely to be either Portuguese Dogfish (Centroscymnus coelolepis) or Leafscale Gulper Shark (Centrophorus squamosus; ICES 2006). This species is one of the most commonly discarded species of deepwater shark in longline fisheries off mainland Portugal and the Azores operating in the Mid-Atlantic Ridge area, and in Spanish fleets in the Celtic Sea and Iberian waters. While it is caught in relatively low quantities, mortality is likely extremely high following discarding. MediterraneanThis shark is caught across the Mediterranean Sea mainly as bycatch in bottom trawl and gillnet fisheries, although until the 1930s a targeted traditional longline fishery for this species operated in the Ligurian Sea. In the Balearic Sea, individuals ranging from small juveniles to adults are caught as bycatch by fisheries operating on the continental slope targeting Red Shrimp (Aristeus antennatus) or Norway Lobster (Nephrops norvegicus) at depths between 300 and 675 m (Guallart 1990, Barrull and Mate 2002). These individuals are typically discarded live, but likely have low survival rates following release (Guallart 1990). This shark’s depth range overlaps with that of a number of deepwater fisheries. The life history characteristics, such as a slow individual growth rate and a relatively large size at maturity, make it sensitive to exploitation.

conservationAction:
Based on advice from the International Council for the Exploration of the Sea to end fishing for deepwater sharks, the European Union Fisheries Council established a Total Allowable Catch (TAC) for this species in 2007 (CEC 2012). This TAC was gradually reduced and in 2010 it was set at zero. In 2011, the allowable bycatch was reduced from 10% to 3% of the 2009 TAC and in 2012 it was further reduced to zero (ICES 2013). However, unreported catches of this species likely make this management measure ineffective.National management plans aimed at enhancing conservation and sustainable management for all chondrichthyan species are being developed under the Food and Agriculture Organization of the United Nations International Plan of Action for the Conservation and Management of Sharks (IPOA-Sharks). In 2009 the European Commission Action plan for the Conservation and Management of Sharks was approved, which encourages research programs aimed at the assessment of the conservation status of sharks in the Mediterranean Sea (Serena et al. 2002).Further research should be conducted on the population size and trend of the species.

useAndTrade:
There is no use and trade information for this species in Europe.

redListContributors:
Blasdale, T., Serena, F., Mancusi, C., Ungaro, N. & Fordham, S.


