Spurdog

Spurdog is vulnerable to overexploitation. In the Northeast Atlantic, the latest stock assessment indicates that spurdog is currently not overfished, or subject to overfishing.The spurdog fishery in the Northeast Atlantic has changed significantly in recent years. Restrictive management measures, including a zero TAC for spurdog introduced in 2011, resulted in a major change in reported landings. Between 2005 and 2017, landings declined across all ICES subareas, increasing again slightly from 2017 to 2021.This stock was benchmarked in 2021 with a substantial improvement in data available for the assessment. Results from the current model confirm that spurdog abundance declined due to high exploitation levels in the past, coupled with biological characteristics that make spurdog particularly vulnerable to such intense exploitation. This model also confirms that the stock is recovering from a low in the early- to mid-2000s, and is now above MSY Btrigger (336,796 tonnes). Biomass in 2022 was 540,266 tonnes. The current stock is thought to be around 45% of virgin biomass.Fishing pressure on the stock has declined substantially since the early 2000s. The harvest rate (ages 5-30) is currently well below HR MSY (0.043). In 2021 it was 0.0031. ICES advises that when the MSY approach is applies, catches in 2023 and 2024 should be no more than 17,353 and 17,855 tonnes respectively. This is a significant change from the advice for 2021 and 2022 which was for zero catch. This change is due to the recent benchmark which led to a change in the perception of the stock and reference points.

This fishery has only recently reopened. The TAC has been set in line with advice but it is too soon to know if management measures will be effective in managing the stock.From 2011-2023, there has been a zero Total Allowable Catch (TAC) in place for spurdog and it was on prohibited lists of both the EU and UK. In July 2016, an amendment to EU quota regulation allowed for a bycatch quota of 270 tonnes for those countries taking part in a pilot spurdog avoidance programme. During 2018, 2019 and 2020, UK reported landings of 37, 52 and 79 tonnes, respectively. For the UK, this was a major increase from a level close to zero that has been seen since the zero TAC was introduced in 2011.In 2022, a change in perception of the stock and reference points led to ICES recommending a catch of 17,353 tonnes in 2023. Subsequently, three TAC units have been proposed for spurdog in the Northeast Atlantic:North Sea (3,434 tonnes)Western (10,899 tonnes)Skagerrak (1,130 tonnes)The UK will have an 81% share in the North Sea unit and a 44.31% share in the Western unit. The prohibition on landing spurdog in EU waters was lifted in January 2023, and in the UK, was lifted on 1st April 2023.As a precautionary measure to protect mature and breeding females, all spurdog over 100cm must be discarded. Specimens 100cm or less must be landed under the Landing Obligation. It is not yet known how well this size limit will be enforced. Estimates of post-release mortality range from 6% to 29%.This is a newly reopened fishery and it is too soon to know if management measures in place will be effective. We would like to see fisheries management plans in place for all UK fisheries, including spurdog.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.Historically, spurdog was taken in large target fisheries but since the fishery was prohibited in 2011, is has been taken as bycatch in mixed demersal trawl fisheries.Trammel nets are a wall of net divided into three layers. An inner fine-meshed net is sandwiched between two outer, larger meshed nets. The net is anchored at the base and floated by the headline, allowing it to hang vertically. The inner net is looser than the outer ones, ensuring that the fish become entangled within it. This is a method with little or no impact on the seabed but it can be associated with bycatch, including harbour porpoises, seals, rays, skates and seabirds.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.Catching large numbers of spurdog in nets can negatively impact the survival of the other species in that net. Spurdog damage other species because their skin is extremely rough and they have spines on their skin. When caught in longline fisheries, spurdog survival rates are higher.

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