Dover sole
Solea solea
What to check for
Location
North Sea
Technical location
Atlantic, Northeast, North Sea
Caught by
Electrical fishing (pulse trawl)
Rating summary
Updated: July 2021.Whilst the stock in this area is recovering and harvested within sustainable limits, fishing with beam trawl using electrical pulse current in UK waters is prohibited by law as of 1st July 2021. Therefore, any species caught by pulse trawl after this date have been caught illegally, leading to a default red-rating.
How we worked out this Rating
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.
Fishing with beam trawl using electrical pulse current in UK waters is prohibited by law as of 1st July 2021. Therefore, any species caught by pulse trawl after this date have been caught illegally, leading to a default red-rating.
References
EU, 2018. Regulation 2018/973 establishing a multiannual plan for demersal stocks in the North Sea and the fisheries exploiting those stocks. Available at https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32018R0973&from=EN [Accessed on 14.07.2021].EU, 2019. Regulation 2019/1241 of the European Parliament and of the Council. Part D - The use of electric pulse trawls in ICES divisions 4b and 4c. Available at https://www.legislation.gov.uk/eur/2019/1241/annex/V/part/D# [Accessed on 16.07.2021].ICES. 2020. Working Group on the Assessment of Demersal Stocks in the North Sea and Skagerrak (WGNSSK). ICES Scientific Reports. 2:61. 1140 pp. Available at http://doi.org/10.17895/ices.pub.6092 [Accessed on 14.07.2021].ICES. 2020. Request of the Netherlands on the ecosystem and environmental impacts of pulse trawling for the sole (Solea solea) fishery in the North Sea. In Report of the ICES Advisory Committee, 2020. ICES Advice 2020, sr.2020.03. Available at https://doi.org/10.17895/ices.advice.6020. [Accessed on 16.07.2021].ICES. 2021. Sole (Solea solea) in Subarea 4 (North Sea). In Report of the ICES Advisory Committee, 2021. ICES Advice 2021, sol.27.4. Available at https://doi.org/10.17895/ices.advice.7859. [Accessed on 16.07.2021].Seafish, 2019. RASS Profile: Sole in the Southern North Sea (ICES Sub Area 4), Beam trawl. Available at https://www.seafish.org/risk-assessment-for-sourcing-seafood/profile/sole-in-the-southern-north-sea-ices-sub-area-4-beam-trawl [Accessed on 16.07.2021].WWF, 2017. Remote Electronic Monitoring in UK Fisheries Management 2017. Available at https://www.wwf.org.uk/sites/default/files/2017-10/Remote%20Electronic%20Monitoring%20in%20UK%20Fisheries%20Management_WWF.pdf [Accessed on 14.07.2021].
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