Coley
Pollachius virens
What to check for
Location
North Sea, West of Scotland and Rockall, Skagerrak
Technical location
Atlantic, Northeast, North Sea, Rockall, West of Scotland, Skagerrak and Kattegat
Caught by
Bottom trawl (otter)
Certification
Marine Stewardship Council (MSC)
Rating summary
The population of coley, or saithe, in the North Sea, West of Scotland and Rockall, and Skagerrak is fully fished but not subject to overfishing. Management measures are in place and generally effective, although there is no specific management plan for this fishery. The certified fleet has taken steps to reduce the impacts of trawling on seabed habitats, and avoid bycatching the vulnerable North Sea cod stock.Rating last updated August 2024.
How we worked out this Rating
Coley, or saithe, in the North Sea, West of Scotland and Rockall, and Skagerrak are overfished and fishing pressure is above target levels.Coley catches peaked at over 400,000 tonnes in the 1970s. Throughout the 1990s and 2000s catches were fairly stable at around 100,000t but have since declined. Catches in 2021 and 2022 were around 50,000t - the lowest on record, but have increased slightly in 2024 to around 60,000t.Stock assessments are carried out annually by the International Council for the Exploration of the Sea (ICES). The most recent assessment was published in 2025 using data up to 2025. The next assessment is expected in 2026.The stock assessment defines reference points for fishing pressure (F) and biomass (B). For fishing pressure, there is a target to keep F at or below Maximum Sustainable Yield (MSY). For biomass, there is no target. However, there is a trigger point (MSY BTrigger). Below this level, F should be reduced to allow the stock to increase. Because BMSY is not defined, the Good Fish Guide applies its own definition of 1.4 x MSY BTrigger.Spawning-stock biomass (SSB) declined from a peak of over 580,000 tonnes in the 1970s to around 100,000t in the 1990s. After a small increase to 250,000t in the 2000s, it declined again. Following the 2024 benchmark assessment, Spawning stock biomass (SSB) in 2025 was 135,337t, below MSY Btrigger (180,770t) and GFG Bpa proxy (155,430t) and 4% above Blim (130,090t). Therefore, there is concern for the biomass and the stock is at an increased risk of depletion.Fishing mortality (F) has decreased from a peak of around 0.7 in the 1980s to fluctuate between a level associated with Maximum Sustainable Yield (FMSY, 0.316) and the precautionary limit (Fpa, 0.392). In 2024, F was 0.34, which is above FMSY (0.316). Therefore, fishing pressure is above target levels.ICES advises that when the MSY approach is applied, catches in 2026 should not exceed 60,167 tonnes. This is a 24% decrease from the previous year's advice, owing to a lower stock levels and proportion of mature stock.
Management measures are in place and generally effective, although there is no specific management plan for this fishery. Part of the fishery is MSC certified, but the certification is conditional on improving management.There are several Marine Stewardship Council (MSC)-certified fisheries for saithe in the North Sea. The main one relevant to the UK is the Scottish Fisheries Sustainable Accreditation Group (SFSAG), which accounted for 11% of the total saithe TAC in 2020. SFSAG has put in place some voluntary measures to improve selectivity and avoid vulnerable habitats. There are some conditions on the certification, relating to ensuring that there is a strategy to recover the stock if it falls below target levels. Other management measures are detailed below.Catches of coley in the North Sea and West of Scotland are mainly made by Norway (around 50% of the landings), followed by France, the UK, and Germany. The EU has a Multiannual Plan (MAP) for its fleets, but Norway and the UK are not part of it. Instead, there is a separate agreed management approach between the EU, UK, and Norway, which includes an agreement to develop a joint long-term management plan.Catch limits, known as Total Allowable Catches (TACs), are the main management measure. TACs are determined based on annual stock assessments by the International Council for the Exploration of the Sea (ICES) and are divided among different fishing areas, based on average landings from 1993-1998. Areas 4 and 3a (North Sea, Skagerrak and Kattegat) get 90.6% and area 6 (Rockall and West of Scotland) gets 9.4%.The combined TACs from 2019-2024 aligned with ICES advice, indicating that management is following scientific recommendations. However, catches in some years exceeded the TACs, suggesting potential compliance issues. Total catches (landings + discards) from 2019-2023 averaged 103% of the advice. In 2020 and 2021 they were 10% and 17% above the advice, respectively, but catches were almost in line with advice in 2023. Average catches are only slightly above the advice.Other management measures include:Real-time closures: For cod, haddock, saithe and whiting in the North Sea and Skagerrak, if more than 10% of the catch by weight is juveniles (smaller than 35cm, 30cm, 35cm, or 27cm respectively), the area in which they were caught is closed for 3 weeks.Minimum conservation reference size: saithe can legally be caught and sold at 35 cm in the North Sea and west of Scotland and 30 cm in the Skagerrak. Below this size, saithe have to be landed but can't be sold for human consumption and so have a lower value.Landing obligation: it is illegal to discard unwanted (e.g. below-minimum-size, BMS) saithe at sea, although there are a number of exemptions for this species. Saithe doesn't enter the fishery until after they migrate offshore at age three. They are usually found in dense shoals of fish of similar size. Therefore, catches of undersize fish are low. However, discarding still takes place, especially in Scottish fleets that don't have quota. ICES indicates that discarding in the North Sea is substantial, but declined from 7.9% in 2018 to 1.8% in 2021, but has since increased to 8%.Various other measures are in place to protect young fish, spawning areas, sensitive species, and marine habitats. There are some closed areas to protect juveniles and vulnerable habitats. In the EU and UK, the minimum mesh size that trawl nets may use is 120mm, to prevent catching undersize cod, haddock or saithe. Smaller mesh can be used if by-catches of those species do not exceed 20% of the total by weight, or if there are selectivity modifications. In Norway, the minimum mesh size is 120mm south of 64 degrees N and 130mm north of it.The EU and UK both have fishery management measures, which can include catch limits, population targets, and gear restrictions. However, compliance in the EU and UK has been inconsistent, with ongoing challenges in implementing some regulations. The goal of reaching Maximum Sustainable Yield (MSY) by 2020 was missed, with less than half of UK TACs in 2024 following ICES advice. In 2024, the EU and UK reaffirmed their commitment to sustainable fisheries by aligning management with scientific advice to gradually approach MSY. However, no new target date has been set for achieving MSY across all fisheries.The Marine Conservation Society views Remote Electronic Monitoring (REM) with cameras is one of the most cost-effective tools for providing reliable fisheries data and aiding informed management decisions. Fully monitored fisheries enhance collaboration, data accuracy, stock recovery, and reduce impacts on marine wildlife and habitats. However, the full potential of REM may only be achieved when it tracks fishing location and documents catch and bycatch, particularly where vulnerable species and habitats are at risk. As of January 2024, the EU is introducing a Remote Electronic Monitoring (REM) mandate for EU vessels, including CCTV cameras on vessels 18m or more that pose a potential risk of non-compliance, within the next 4 years. Across the UK, different approaches to REM are being taken and legislation is expected to be in place across all 4 countries within the next few years.The Fisheries Act (2020) requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans) in the UK. 43 FMPs have been proposed and are at various stages of development and implementation, these should all be published by the end of 2028. FMPs have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. It is also essential the UK governments define and adopt a standardised approach or model across the four nations to a universally defined FMP design, to ensure the consistence, quality and coherence of all the proposal FMPs.The Marine Conservation Society is keen to see publicly available Fishery Management Plans for all commercially exploited stocks, especially where stocks are depleted, that include:An overview of the fishery including current stock status, spatial coverage, current fishing methods and impactsTargets for fishing pressure and biomass, and additional management when those targets are not being met, based on the best scientific evidenceTimeframes for stock recoveryImproved data collection, transparency, and accountability, supported by technologies such as Remote Electronic Monitoring (REM)Consideration of wider environmental impacts of the fishery, including habitat impacts and minimising bycatchStakeholder engagementA North Sea and West Coast of Scotland Saithe FMP has been proposed, coordinated by Marine Scotland that incorporates this stock. At the time of writing, it is too soon to know whether proposed management measures will be effective in managing the stock. For more information about this FMP and expected progress and timelines, see [https://www.gov.uk/government/collections/fisheries-management-plans#published-fmps].
Most saithe catches are by otter trawls, which are likely to cause some damage to the seabed. Bycatch is moderate and may include vulnerable species such as blue and flapper skate, and cod. In the certified component of the fishery, vessels have implemented measures to improve monitoring and reduce bycatch.Most coley (around 81%) is caught by bottom otter trawling. Around 90% of the catch comes from the North Sea and Skagerrak, and around 10% from western Scotland. Saithe is usually caught in deeper waters than other gadoids (cod, haddock, and whiting): up to 500m in the North Sea and up to 800m west of Scotland.Demersal otter trawls have the potential to take relatively high quantities of bycatch. In the Northeast Atlantic there are reported catches of demersal elasmobranchs and endangered, threatened and protected (ETP) species (e.g. sharks, rays and marine mammals). Bycatch data is limited in many UK and EU fisheries as they are generally not well monitored. However, a proportion of the trawl fisheries in the North Sea are Marine Stewardship Council-certified and record bycatch. The Marine Conservation Society assumes these records would also represent bycatch concerns in the uncertified components. Bycatch includes North Sea cod and West of Scotland cod and whiting, which are at very low levels. Endangered, threatened or protected species included the Critically Endangered common skate complex (blue skate and flapper skate), porbeagle, and other skates and rays.Some mitigation measures are in place in some areas. There is a UK North Sea cod avoidance plan, requiring a minimum 120mm mesh size in the Scottish North Sea, seasonal closures to protect spawning stocks, and a requirement to move away from areas where large numbers of cod are observed in catches. In Sweden, vessels have increased bycatch avoidance measures by using larger-meshed panels in their nets, which allow juvenile cod to escape. ICES indicates that the roundfish-directed fishery (demersal trawling with over 120mm mesh size) has the biggest impact on the North Sea cod stock, accounting for 75% of catches. Therefore, this fishery is likely to be affecting the population.Work is underway to trial selective gears and develop tools to reduce bycatch. In the West of Scotland, this includes BATmap (By-catch Avoidance Tool using mapping), launched in 2020. It allows real-time reporting of bycatch of cod and spurdog to identify areas for skippers to avoid. Work is ongoing to refine and roll it out further. Innovation such as this is a very positive and vital step forward for minimising bycatch in mixed fisheries.For blue and flapper skate, mitigation measures include a prohibition on landing either species and some protection for nursery areas. It is not clear if this fishery is having an impact at population level for any of these species. Given that bycatch is ongoing, the Marine Conservation Society considers it possible that the bycatch level is contributing to population decline and/or preventing recovery.Fishing effort in the Celtic Seas region decreased by 35% between 2003 and 2014, which is reducing pressure on the seabed and on bycatch species. An estimated 61% of the Celtic Sea region, which extends from western Scotland to the English Channel, was trawled in 2022. 88% of the zone between 400m and 800m has been fished. From 2009-2011, 95% of areas containing VMEs were fished. Fishing-induced physical disturbance is estimated to have resulted in an overall decrease of invertebrate benthic biomass varying between 59% in offshore mud and 5% in sandy habitats compared to an unfished state. This impact is patchy and may be over 80% in the most heavily fished areas.Mitigation measures include a ban on bottom trawling below 800m, and restrictions from 400-600m – the areas where most VMEs are found. There remains some uncertainty about the location of some sensitive seabed habitats, so these remain at risk. It is estimated that approximately 70% of seapen habitat in this area is closed to fishing, through inaccessibility to trawls or Marine Protected Areas (MPAs).If Marine Protected Areas are well-managed, they can provide protection to VMEs, but poorly-managed MPAs will mean they are at risk. Given the important role that MPAs have in recovering the health and function of our seas, the Marine Conservation Society encourages the supply chain to identify if their specific sources are being caught from within MPAs. If sources are suspected of coming from within designated and managed MPAs, the Marine Conservation Society advises businesses to establish if the fishing activity is operating legally inside a designated and managed MPA, and request evidence from the fishery or managing authority to demonstrate that the activity is not damaging to protected features or a threat to the conservation objectives of the site(s).To improve monitoring and reporting of fishing activity the Marine Conservation Society would like to see remote electronic monitoring (REM) with cameras implemented, used and enforced. To reduce the impacts of fishing on the marine environment we would like to see a just transition to the complete removal of bottom towed gear from offshore Marine Protected Areas designated to protect the seabed. We also want to see reduction and mitigation of environmental impacts including emissions and blue carbon habitat damage.The Scottish Fisheries Sustainable Accreditation Group (SFSAG) is certified for whiting, haddock, hake, plaice and saithe in the North Sea. It has put in place some voluntary measures to improve selectivity and avoid vulnerable habitats. Some actions are needed to mitigate capture method impacts:Cod: better management is needed to ensure bycatch is not hindering recovery, demonstrated by evidence that the stock is rebuilding.Habitats: more information and a strategy is needed to guarantee that the fishery is not impacting vulnerable habitats.
References
Anon, 2022. Agreed record of fisheries consultations between the European Union, Norway and the United Kingdom for 2023. 9 December 2022. Available at https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1123184/Agreed_record_of_fisheries_consultations_between_the_European_Union__Norway_and_the_United_Kingdom_for_2023.pdf [[Accessed on 25.07.2024].Cook, R., Gaudian, G., des Clers, S. and Seip- Markensteijn, C.M., 2022. Marine Stewardship Council (MSC) Public Certification Report: Scottish Fisheries Sustainable Accreditation Group (SFSAG) Northern Demersal Stocks. Prepared by Control Union (UK) Limited on behalf of Scottish Fisheries Sustainable Accreditation Group (SFSAG). May 2022. Available at https://cert.msc.org/FileLoader/FileLinkDownload.asmx/GetFile?encryptedKey=BdxOJoY7Sf4DmNJEB/m47M6xx0rRfgP/niGx3vj5Ud8hadYI3XCNrnlSFL/jlTgK [Accessed on 25.07.2024].Eigaard, O. R., Bastardie, F., Breen, M., Dinesen, G. E., Hintzen, N. T., Laffargue, P., Mortensen, L. O., Nielsen, J. R., Nilsson, H. C., O- Neill, F. G., Polet, H., Reid, D. G., Sala, A., Skold, M., Smith, C., Sorensen, T. K., Tully, O., Zengin, M. and Rijnsdorp, A. D., 2016. Estimating seabed pressure from demersal trawls, seines, and dredges based on gear design and dimensions. ICES Journal of Marine Science, 73:1, pp. i27- i43. https://doi.org/10.1093/icesjms/fsv099.Hiddink, J., Jennings, S., Sciberras, M., Szostek, C.L., Hughes, K.M., Ellis, N., Rijnsdorp, A.D., McConnaughey, R.A., Mazor, T., Hilborn, R., Collie, J.S., Pitcher, C.R., Amoroso, R.O., Parma, A.M., Suuronen, P. and Kaiser, M.J. 2017. Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance. PNAS. 114:31, pp. 8301-8306. https://doi.org/10.1073/pnas.1618858114.ICES. 2024a. Celtic Seas Ecoregion – Ecosystem overview. In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, Section 7.1, Available at: https://doi.org/10.17895/ices.advice.25713033 [Accessed on 25.07.2024]ICES. 2024b. Greater North Sea ecoregion – Ecosystem overview. In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, Section 7.1, Available at: https://doi.org/10.17895/ices.advice.25714239 [Accessed on 25.07.2024].ICES, 2024c. Saithe (Pollachius virens) in subareas 4 and 6, and in Division 3.a (North Sea, Rockall and West of Scotland, Skagerrak and Kattegat). In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, pok.27.3a46, Available at: https://doi.org/10.17895/ices.advice.25019465 [Accessed on 25.07.2024].ICES, 2024d. Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak (WGNSSK). ICES Scientific Reports. 6:38. 1249 pp. Available at: https://doi.org/10.17895/ices.pub.25605639 [Accessed on 25.07.2024].ICES, 2023. Stock Annex: Cod (Gadus morhua) in Subarea 4, divisions 6.a and 7.d, and Subdivision 20 (North Sea, West of Scotland, eastern English Channel, Skagerrak). ICES Stock Annexes. 36 pp. Available at: https://doi.org/10.17895/ices.pub.22633843.v2 [Accessed 19.07.2024].Kennelly, S. J. & Broadhurst, M. K., 2021. A review of bycatch reduction in demersal fish trawls. Rev Fish Biol Fisheries 31, 289–318. https://doi.org/10.1007/s11160-021-09644-0.Kynoch, R., Fryer, R. & Neat, F., 2015. A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries. ICES J Mar Sci,72(6):1861.MMO, 2020. UK National North Sea Cod Avoidance Plan. Issued December 2020., Updated: 18 January 2023 Available at https://www.gov.uk/government/publications/uk-national-north-sea-cod-avoidance-plan [Accessed on 25.07.2024].Silva, F., Ellis, J. & Catchpole, T., 2012. Species composition of skates (Rajidae) in commercial fisheries around the British Isles and their discarding patterns. J Fish Biol., 80:1678–1703.van Denderen, P. Bolam, S., Hiddink, J.G., Jennings, S., Kenny, A., Rijnsdorp, A., and van Kooten, T., 2015. Similar effects of bottom trawling and natural disturbance on composition and function of benthic communities across habitats. Mar Ecol Prog Ser. 2015;541:31–43.Wilson, D., Borges, L., Hoare, D., and Norbury, H., 2023. Marine Stewardship Council (MSC) 1 st Surveillance Audit Report: SFSAG Northern Demersal stocks. Prepared by Control Union (UK) Limited on behalf of Scottish Fisheries Sustainability Accreditation Group (SFSAG). October 2023. Available at:https://cert.msc.org/FileLoader/FileLinkDownload.asmx/GetFile?encryptedKey=hJcPTKb9wBBNs44CBo73WtCO6werzCJbk6+jM81mPCGscZM3CEGZgEnvwk6xCPbj [Accessed 25.07.2024].Wilson, D., and Hoare, D., 2024. Marine Stewardship Council (MSC) Expedited Audit Report: Scottish Fisheries Sustainable Accreditation Group (SFSAG) Northern Demersal Stocks. Prepared by Control Union (UK). January 2024. Available at: https://cert.msc.org/FileLoader/FileLinkDownload.asmx/GetFile?encryptedKey=Xv7xLIUTO2PJa0ncg0qcsq5nqj00vNPiR9xn4NUhL8ZuOFrAY83/Hvm3IPJG0dd5 [Accessed on 25.07.2024].
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