Thornback ray

The population of thornback ray in the North Sea, Skagerrak, Kattegat, and Eastern English Channel is above target levels, and fishing is within sustainable limits.This stock was benchmarked in 2023. Spawning-stock biomass have been increasing since 2008, and is currently high, above MSY Btrigger. Fishing pressure on the stock has been below FMSY since 2007. ICES advises that when the precautionary approach is applied, catches in 2024 and 2025 should be no more than 5,274 and 5,307 tonnes, respectively. This is a 116% increase in advice due to the stock benchmark moving this from an ICES category 3 to category 2 stock. However, catch advice is much higher than what recent catches have been.Thornback ray is also taken in recreational fisheries, and the retained catches are unquantified.

Thornback ray is a vulnerable species and management needs to be more precautionary. The joint TAC in place is not a suitable management method.There is no management plan in place for thornback ray in this area. Demersal elasmobranchs are usually caught as bycatch in the mixed demersal fisheries for roundfish and flatfish. Thornback ray is the main commercial skate species in the North Sea and eastern English Channel.In 1999, a common Total Allowable Catch (TAC) for 'skates and rays' was first introduced. Five regional quotas are in place for the group of skates and rays, rather than for the individual species. This method of management has been deemed as unsuitable for protecting individual species, but species-specific quotas may also lead to discarding. In 2023, the TAC for skates and rays were set as follows:1,764 tonnes for ICES areas 2.a and 4 (68% UK)48 tonnes for ICES area 3.a9,797 tonnes for ICES areas 6.a, 6.b, 7a-c, and 7e-k (30% UK)1,537 tonnes for ICES area 7.d (16% UK)5,519 tonnes for ICES areas 8 and 9 (0.2% UK)In addition, in North Sea waters, vessels larger than 15m, are only permitted to land a maximum of 25% of the catch (whole weight) as skates and rays.Skates and rays caught in the Northwest waters (ICES subareas 6 and 7) and North Sea waters (ICES subareas 2a, 3a and 4) with all fishing gears, are exempt from the landing obligation, based on their high survivability rates. Any skates and rays that are discarded are required to be released immediately and below the sea surface.There is no official minimum conservation reference size (MCRS) in place but some of the UK's Inshore Fisheries and Conservation Authorities (IFCAs) have an MCRS of 40cm disc width for skates and rays.Thornback ray caught in Skagerrak and Kattegat is a prohibited species and should be unharmed and promptly released when accidentally caught.Both the EU and UK have fishery management measures in place, which can include catch limits, targets for population sizes and fishing mortality, and controls on what fishing gear can be used and where. In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them. There was a target for fishing to be at Maximum Sustainable Yield by 2020, but this was not achieved.In the UK, it is too early to tell how effective management is, as the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans) but there are no details yet on how and when these will be developed. FMPs have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. MCS is keen to see FMPs for all commercially exploited stocks, especially where stocks are depleted, that include:Targets for fishing pressure and biomass, and additional management when those targets are not being metTimeframes for stock recoveryTechnologies such as Remote Electronic Monitoring (REM) to support data collection and improve transparency and accountabilityConsideration of wider environmental impacts of the fishery

Gillnets can be very size selective for the target fish but can be unselective at the species level for both non-target fish and for mammals, birds and turtles.Thornback ray in this area are caught by beam trawls (17%), other bottom trawls (51%), set nets (15%) and other gears (17%). It is an important commercial species, however, around 20% of the catch is still discarded.Gillnets and fixed nets can be very size selective, but can bycatch species such as sharks, cetaceans and other marine mammals. Reports indicate that there is concern regarding the bycatch of cetaceans, particularly harbour porpoise, by gillnets. The IUCN lists harbour porpoise as being of least concern globally, but vulnerable in Europe. They are also classified as a priority species under the UK Post-2010 Biodiversity Framework and are protected under the European Union (EU) Habitats Directive and Habitats Regulations as transposed into UK law, under which there are explicit bycatch requirements. To comply with the Habitats Directive, the UK has recently designated five Special Areas for Conservation for harbour porpoises, however, there is currently no management in place for these.One of the areas of most concern is off the South West of England, where areas of higher gillnet fishing effort coincide with areas of larger harbour porpoise populations. While cetacean bycatch has been a long-term problem around Cornwall, the occurrence of stranded cetaceans has increased over the last two decades. In 2019, 24% of stranded cetaceans exhibited features consistent with bycatch or entanglement in fishing gear, a further 19% were assessed as being possible bycatch, and 52% had an unknown cause of death. However, this stock does not cover the Western English Channel, and harbour porpoise bycatch is not considered to be a problem in the Eastern English Channel.Because of gillnets' durability (they are made of nylon), if lost, they can continue to fish for several weeks before becoming tangled and bundled up, a phenomenon known as 'ghost fishing'. However, static nets, as with all gear, represent an investment by fishermen, and therefore there are incentives to avoid losing or damaging gear. Fish caught in trammel nets are often very good quality as they are not damaged by the capture process.

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