Common Skate
Common Name: Common Skate
Scientific Name: *Dipturus batis (synonyme: Raja batis)
Description: The common skate is the largest skate in the world, attaining a length of up to 2.85 m (9 ft 4 in). Historically, it was one of the most abundant skates in the northeast Atlantic Ocean and the Mediterranean Sea. Despite its name, today it appears to be absent from much of this range. Where previously abundant, fisheries directly targeted this skate and elsewhere it is caught incidentally as bycatch. The species was uplisted to critically endangered on the IUCN Red List in 2006 and it is protected within the EU.
OSPAR Regions where it occurs: I, II, III, IV, V
OSPAR Regions where under threat and/or in decline: I, II, III, IV, V
What is the latest status of the common skate?
The status assessment describes the latest changes in distribution, abundance and range of the feature, as well as any changes in the threats and pressures impacting the feature. The status assessments are updated regularly and inform OSPAR’s consideration of the effectiveness of the measures and actions that have been adopted and implemented by Contracting Parties.
Why is this feature included on the OSPAR List? |  | |||
What protective measures and actions has OSPAR committed to taking? |  |  | ||
What actions have been implemented by OSPAR? |
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Key message
The common skate complex is considered to be ‘Critically Endangered’ globally by the IUCN, with both species (i.e. common blue skate Dipturus batis and flapper skate Dipturus intermedius) considered to be Critically Endangered in European waters. While there have been positive signs in the stocks of both species in parts of OSPAR Regions II and III, in terms of increasing catch rates as indicative measures of improvement, both species are still infrequently recorded or absent from some former parts of their geographic range. Both species of the common skate complex are on the prohibited species list according to EU fishing regulations.
For more information, please visit our latest status assessment
Threats and Impacts
Fishing pressure is considered to be the most important threat to populations of both species of skate. It has been prohibited to land both species from EU waters since 2009, which should reduce the mortality rates. Both species are bycaught in bottom trawl and set net fisheries however and discard survival, though likely to occur, has not been quantified.
ICES noted an increase in reported landings of long-nosed skate since the prohibition on landing “common skate-complex”, which may reflect some misreporting. The impacts of other fisheries (e.g. deep-water and recreational fisheries) have not been evaluated.
Common skate complex species predate on a wide variety of demersal fish and crustaceans, suggesting prey availability may not be limiting.
For more information, please visit our latest status assessment
Measures that address key pressures from human activities or conserve the common skate
EU fishing regulations have listed Dipturus batis and D. intermedius as prohibited species in EU waters since 2009, which should reduce fishing mortality. Both species should be promptly released unharmed by fishers, and they cannot be landed. Regulation (EU) 2015/812 (EU 2015) requires that all discards of common skate in EU waters are recorded by commercial fishers. Catch rates of species in the complex have increased in scientific trawl surveys since the prohibition (ICES 2020a), suggesting that the measure has benefited the populations. The Loch Sunart to the Sound of Jura Marine Conservation Order (UK Legislation, 2016) lists “common skate” as the designation feature of this MPA, which should reduce fishing mortality and maintain habitat in an important area for the species.
For more information, please visit our latest status assessment
