Dover sole

Sole biomass in the North Sea is in a good state and fishing pressure is within sustainable limits.Stock assessments are carried out annually by the International Council for Exploration of the Sea (ICES). The most recent assessment was published in 2024.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.In 2023, spawning stock biomass (SSB) is 55,955 tonnes. This is a decline from a recent peak in 2021, but it remains above MSY Btrigger (52,532 tonnes). In 2025, it is predicted to increase further to 61,320 tonnes. However, recruitment in the last 5 years has been relatively low.Fishing pressure (F) has decreased in recent years from 0.33 in 2011 to 0.079 in 2023. This is below FMSY.ICES advises that when the MSY approach is applied, catches in 2025 should be no more than 10,196 tonnes. This is an increase of 177% from the previous years advice due to the upward revision of stock status after the recent benchmark. The SSB for the stock was previously estimated around Blim and SSB is now above MSY Btrigger.

There is no management plan in place for North Sea Dover sole, but some measures are in place which are largely effective. Discarding is high for this stock.The sole fishery in the North Sea is managed by Total Allowable Catch (TAC) and technical measures. TAC has been set in line with scientific advice in recent years and catches have been in line with the TAC. Since 2022, the TAC has followed the MSY approach, rather than having an upper and lower limit. In 2025, advice has increase substantially, however, TAC uptake has been less than 100% in recent years and it is thought that catch will remain below advice.Sole in the North Sea has been under the landing obligation since 2016, and Norway and UK national legislation regarding discards. Catch monitoring programs estimate that discarding in 2023 amounted to 8.22% of the total catch (includes below minimum size landings (BMS)).Technical measures in place for this fishery are:Minimum mesh sizes and minimum conservation reference size (MCRS) of 24cm.Mesh size regulations for towed trawl gears require that vessels fishing North of 55°N (or 56°N east of 5°E, since January 2000) should have a minimum mesh size of 100 mm, while to the south of this limit, where the majority of the sole fishery takes place, an 80 mm mesh is allowed. In the fishery with fixed gears a minimum mesh size of 100 mm is required.A closed area has been in operation since 1989 (the plaice box) - this applies to vessels using towed gears, but vessels smaller than 300 HP are exempt.In the plaice box, and in the 12 nautical mile zone, the maximum aggregated beam length is 9m.Between 2014 and 2018 the use of pulse trawls in the main fishery operating in the North Sea increased and fewer vessels were operating with traditional beam trawls. The pulse gear allows fishing of softer grounds and as a result the spatial distribution of the main fisheries has changed to the southern part of the Division 4.c. As a consequence, a larger proportion of the sole catch is now taken in this area. Following the EU decision in February 2019 to revise the technical measures regulations, the pulse gear was prohibited from 1st July 2021. It is expected that the fleets will revert to the traditional gears and fishing grounds.A number of Marine Stewardship Council certifications are available for North Sea sole.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 Landing Obligation (LO), an EU law retained by the UK post-Brexit, requires all quota fish to be landed, even if unwanted (over-quota or below minimum size). It aims to encourage more selective fishing methods, reduce bycatch, and improve catch reporting. However, compliance is poor, and accurate discard levels are hard to quantify with current monitoring programmes. The UK is in the process of replacing the LO with country-specific Catching Policies.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 Southern North Sea and Eastern Channel mixed flatfish FMP has been proposed, coordinated by Defra that covers the English waters within ICES divisions 4b, 4c and 7d. The FMP covers the following flatfish species (quota and non-quota): sole, dab, plaice, flounder, halibut, lemon sole, witch, turbot, brill. It is too soon to know whether the 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.

Benthic seines interact with the seabed and have the potential to cause some damage to sea floor habitats, but the majority of the interaction comes from ropes which have a lighter impact than otter and beam trawl fisheries.Dover sole in the North Sea are taken by beam trawlers (93%), gillnets and trammel nets (3%), bottom trawls (3%) and other gear types (1%).Demersal seines consist of a net that is anchored to the bottom, with two ropes or sweeps that are winched in, thereby closing the net. Scottish seines, or fly-shoots, work on the same principle, but are towed along the seabed while winching in the ropes.There are few studies on the impacts of demersal seining. Demersal seines do not have heavy gear such as otter boards that demersal trawls use, and therefore most seabed contact happens at the surface rather than subsurface level, resulting in a lower impact. However, Scottish seines may have a higher impact from being towed and may use heavier gear.There are Marine Protected Areas (MPAs) in this area, some of which are designated to protect seabed features from damaging activities. This fishery overlaps with parts of these MPAs, but the proportion of the catch coming from these areas is expected to be relatively low in relation to the unit of assessment (i.e. less than 20% of the catch or effort), and so these impacts have not been assessed within the scale of this rating. Given the important role that MPAs have in recovering the health and function of our seas, MCS 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, MCS 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).Bycatch data is limited in many UK and EU fisheries as they are generally not well monitored. A risk assessment of bycatch in fishing activities indicates a low risk of seabird bycatch in demersal seines and a medium risk of cetacean bycatch. However, most recorded cetacean bycatch is by gillnetting, which is more likely to be a driver of trends in cetacean populations.Demersal seine fisheries can encounter bycatch of other fish species, including juveniles of commercial species, but as lemon sole itself is considered a bycatch species of other targeted fisheries (often for dover sole and plaice), this component has not been assessed in this rating.To improve monitoring and reporting of fishing activity, MCS 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.

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). Available at https://cert.msc.org/FileLoader/FileLinkDownload.asmx/GetFile?encryptedKey=BdxOJoY7Sf4DmNJEB/m47M6xx0rRfgP/niGx3vj5Ud8hadYI3XCNrnlSFL/jlTgK [Accessed on 13.07.2023].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., Rijnsdorp, A.D., 2016. Estimating seabed pressure from demersal trawls, seines, and dredges based on gear design and dimensions. ICES Journal of Marine Science, Volume 73, Issue suppl 1. Pages i27-i43. Available at https://academic.oup.com/icesjms/article/73/suppl_1/i27/2573989 [Accessed on 12.07.2023].Evans, P.G.H., Carrington, C.A., and Waggitt, J.J. (2021) Risk Mapping of Bycatch of Protected Species in Fishing Activities. Sea Watch Foundation & Bangor University, UK. European Commission Contract No. 09029901/2021/844548/ENV.D.3. 212 pages. Available at https://ec.europa.eu/environment/nature/natura2000/marine/docs/RISK%20MAPPING%20REPORT.pdf.Hamon, K.G., S. Glorius, A. Klok, J. Tamis, R. Jongbloed, 2020. Seine fishing on the Dutch and German parts of the Dogger Bank, 2013-2019; Overview of the economic importance and the ecologic impact of the Belgian, British, Danish, Dutch, French, German and Swedish fleets. Wageningen, Wageningen University & Research, Report 2020-105. 46 pp. Available at https://edepot.wur.nl/533439ICES. 2021. Greater North Sea Sea Ecoregion – Ecosystem overview. In Report of the ICES Advisory Committee, 2021. ICES Advice 2021, Section 9.1, https://doi.org/10.17895/ices.advice.9434 [Accessed on 19.07.2022].ICES. 2023. Sole (Solea solea) in Subarea 4 (North Sea). In Report of the ICES Advisory Committee, 2023. ICES Advice 2023, sol.27.4. Available at https://doi.org/10.17895/ices.advice.21841017 [Accessed on 19.07.2023].