Dover sole
Solea solea
What to check for
Location
English Channel (West)
Technical location
Atlantic, Northeast, English Channel (West)
Caught by
Net (gill or fixed)
Rating summary
Western English Channel sole is in a good state, and fishing mortality is at sustainable levels. There is no management plan in place for this fishery but some measures are in place, and total allowable catch (TAC) is generally set in line with scientific advice. This fishery has a low level of discarding of unwanted fish. In terms of bycatch, plaice is also caught in this fishery and the minimum mesh size is not matched to the lower size limit for plaice, leading to a large number of plaice being discarded. Gillnets in this area can encounter bycatch of non-target fish, mammals and birds. This includes the harbour porpoise which is vulnerable in Europe. Based on the available information, gillnet fisheries in some areas could be over-exploiting this species and causing it to decline.Rating last updated July 2023.
Technical consultation summary
Western English Channel sole biomass is in a good state and fishing pressure is below FMSY. There is no management plan in place for this fishery but some measures are in place, including effort and mesh restrictions. Total allowable catch (TAC) is generally set in line with scientific advice, and there are technical measures such as limits to the number of days at sea for beam trawlers and static nets and a minimum mesh size of 80mm for towed gears. This fishery has a low level of discarding of unwanted fish. In terms of bycatch, plaice is also caught in this fishery and the minimum mesh size is not matched to the lower size limit for plaice, leading to a large number of plaice being discarded. Gillnets in this area can encounter bycatch of non-target fish, mammals and birds. This includes the harbour porpoise which is vulnerable in Europe. Based on the available information, gillnet fisheries in some areas could be over-exploiting this species and causing it to decline.
How we worked out this Rating
Western English Channel sole stock is in a healthy state and fishing pressure is within sustainable levels.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 2024, spawning stock biomass (4,274 tonnes) has declined from a peak in 2020, but remains high and well above MSY Btrigger (2,900 tonnes). Fishing pressure (F) is below FMSY (0.29), at 0.26 in 2023.The base level of recruitment has remained relatively stable throughout the time series, fluctuating without major temporal trend at around 4 million recruits. There was a significant rise in recruitment in 2020 at almost 12 million recruits and this has been lower in subsequent years.ICES advises that when the MSY approach is applied, catches in 2025 should be no more than 1,151 tonnes.
There is no management plan in place for this fishery but some measures are in place, including effort and mesh restrictions.Management of this stock is mainly by total Allowable Catch (TAC). In 2005, effort restrictions were implemented for beam trawlers and entangling gears targeting sole in this fishery to enforce the TAC and improve data quality.Since 2013, Total Allowable Catches (TACs) have been in line with or below the scientific advice, and landings have been in line with TACs. Official landings in 2023 were 1,238 tonnes (preliminary), below the TAC which was set at 1394 tonnes. For 2024, the TAC was reduced to 1,184 tonnes.In this area, there is a mixed fishery for sole and plaice and the two stocks are dominant commercially caught species. There can be contrasting changes in catch advice which can lead to higher discards of plaice. In 7.e, 26% of the plaice stock was discarded, compared to 2% of the sole stock. Technical measures in place for this fishery are:Effort restrictions limiting the numbers of days at sea for vessels in this fishery using beam trawls (≥80 mm mesh size) and static nets (≤120 mm mesh size). The limits for effort are set annually in the EU council with the TAC and apply only for vessels, which catch more than 300 kg of sole annually.Baseline mesh size of 100mm with an exception to the 100mm square mesh panel in the area east of 5°W.For more information about this rating in Cornwall please visit: http://www.cornwallgoodseafoodguide.org.uk/fish-guide/sole-dover-sole.phpThe 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 engagement
Gillnets in this area can encounter bycatch of non-target fish, mammals and birds. This includes the harbour porpoise which is vulnerable in Europe.In 2023, catch was 1,241 tonnes, most of this (1,239 tonnes) was landed and discards in this fishery are low. Beam trawl accounts for around 68% of landings, with otter trawl accounting for 16.7% and gillnets, 8.7%. The majority (94%) of discards came from beam trawling.Plaice is taken as bycatch in this fishery, and therefore management advice for sole must also take into account the advice for plaice. The minimum mesh size of 80mm in place leads to a large number of plaice being discarded because this mesh size is not matched to the minimum conservation reference size (MCRS) of 27cm for plaice. The approximate size at which 50% of females mature or first spawn is around 30-34cm. Anglerfish, cuttlefish, and lemon sole are also important bycatches in this fishery.Gillnets and fixed nets can be very size selective, but can bycatch species such as sharks, cetaceans and other marine mammals. In particular, there is concern about bycatch of harbour porpoise. The IUCN lists harbour porpoise as being of least concern globally, but vulnerable in Europe. OSPAR has included the species on its List of Threatened and / or Declining Species and Habitats for the Greater North Sea and Celtic Seas, owing to evidence of a decline in populations, their sensitivity and the threat of incidental capture and drowning in fishing nets. They are also classified as a priority species in UK and EU law, under which there are explicit bycatch requirements. To comply with this, the UK recently designated five Special Areas for Conservation for harbour porpoises, but these areas are not yet managed. The UK Dolphin and Porpoise Conservation Strategy lists harbour porpoise as having 'medium' vulnerability to gillnetting for the UK as a whole. This is based on the species having a high sensitivity to gillnetting and medium exposure.The area of most concern is in the Celtic Seas, southwest of the UK, where most of the UK's gillnetting activity takes place. Exposure to gillnetting is high. A review of activities in the Bristol Channel Approaches Harbour Porpoise SAC lists "commercial fisheries with bycatch (predominantly static nets)" as a high risk, and a strandings report by Cornwall Wildlife Trust also shows that common dolphin bycatch is very high in this area.There is also bycatch of elasmobranch species which may be threatened or endangered. Porbeagle sharks are being caught as bycatch in gillnets but as they are a prohibited species, there is no official data on the numbers being caught and discarded. Spurdog bycatch is also thought to be of concern. The National Evaluation of Populations of Threatened and Uncertain Elasmobranchs (NEPTUNE) highlighted continued problems of spurdog bycatch and despite a supposed real time avoidance programme being implemented, 50 tonnes were still landed in Cornish ports in 2019.There is a relative lack of knowledge on the overall impact of fishing on seabird populations in Europe. Increasing evidence over the last decade has shown that seabirds are suffering mortality from bycatch, particularly in gillnets. Bycatch of seabirds in gillnet fisheries alone is estimated to kill around 400,000 birds globally each year. Diving seabirds, such as guillemots and cormorants, are generally more vulnerable to bycatch in gillnets than surface feeding seabirds. Most of the UK’s gillnetting takes place in the Celtic Seas, southwest of the UK and therefore there is concern for seabird populations here. In particular, species of concern include the razorbill (listed as Near Threatened in Europe by IUCN), puffin (listed as Endangered in Europe by IUCN) and the herring gull, arctic skua and roseate tern which are all classified in the UK as Red under the Birds of Conservation Concern 4: the Red List for Birds (2015).Some pilot projects are underway to improve reporting of bycatch and find ways to reduce it. This includes trialling various types of 'pingers' that would discourage cetaceans from approaching the nets. Pingers have been very effective at reducing porpoise and dolphin bycatch in some fisheries, but haven't been adopted on a large enough scale to significantly tackle the issue. Testing and trials are crucial and may need to be supported by other measures such as seasonal closures.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.
References
Bradbury, G., Shackshaft, M., Scott-Hayward, L., Rexstad, E., Miller, D., and Edwards, D., 2017. Risk assessment of seabird bycatch in UK waters. Produced by Wildfowl & Wetlands Trust (Consulting) Ltd for Defra project MB0126. Available at http://sciencesearch.defra.gov.uk/Document.aspx?Document=14620_MB0126RiskassessmentofseabirdbycatchinUKwaters_updated21Oct2019.pdf [Accessed on 12.07.2024].Calderan, S. and Leaper, R., 2019. Review of harbour porpoise bycatch in UK waters and recommendations for management. January 2019, WWF. Available at https://www.wwf.org.uk/sites/default/files/2019-04/Review_of_harbour_porpoise_in_UK_waters_2019.pdf [Accessed on 12.07.2024].Chadwick, H., Clear, N., Crosby, A., Hawtrey-Collier, A. and Williams, R. Marine Strandings in Cornwall and the Isles of Scilly: 2019 Annual Report. Report by Cornwall Wildlife Trust and Marine Strandings Network. Available at https://www.cornwallwildlifetrust.org.uk/sites/default/files/2020-12/2019%20Summary%20Report%20-%20Marine%20Strandings%20in%20Cornwall%20and%20the%20Isles%20of%20Scilly.pdf [Accessed on 12.07.2024].Cornwall Wildlife Trust. Seabirds. Available at https://www.cornwallwildlifetrust.org.uk/wildlife-explorer/birds/seabirds [Accessed on 12.07.2024].Ellis, J. R., Bendall, V. A., Hetherington, S. J., Silva, J. F. and McCully Phillips, S. R. 2016. National Evaluation of Populations of Threatened and Uncertain Elasmobranchs (NEPTUNE). Project Report (Cefas) V1.4. Available at http://randd.defra.gov.uk/Document.aspx?Document=13513_MB5201NEPTUNEFinalReportv1.4.pdf [Accessed on 12.07.2024].Glemarec, G., Kindt-Larse, L., Scherffenberg Lundgaard, L. and Larsen, F. 2020. Assessing seabird bycatch in gillnet fisheries using electronic monitoring. Biological Conservation. 243. 108461. Available at https://doi.org/10.1016/j.biocon.2020.108461 [Accessed on 12.07.2024].ICES. 2024. Sole (Solea solea) in Division 7.e (western English Channel). In Report of the ICES Advisory Committee, 2024. ICES Advice 2024, sol.27.7e. Available at https://doi.org/10.17895/ices.advice.25019678. [Accessed on 12.07.2024].JNCC. 2019. Harbour porpoise (Phocoena phocoena) Special Area of Conservation: Bristol Channel Approaches / Dynesfeydd Môr Hafren. Conservation Objectives and Advice on Operations. Available at https://data.jncc.gov.uk/data/505b3bab-a974-41e5-991c-c29ef3e01c0a/BCA-ConsAdvice.pdf [Accessed on 12.07.2024].Omeyer, L.C.M., Doherty, P.D., Dolman, S., Enever, R., Reese, A., Tregenza, N., Williams, R. and Godley, B.J. 2020. Assessing the Effects of Banana Pingers as a Bycatch Mitigation Device for Harbour Porpoises (Phocoena phocoena). Frontiers in Marine Science. Front. Mar. Sci. https://doi.org/10.3389/fmars.2020.00285.OSPAR, 2017. Intermediate Assessment 2017: Harbour Porpoise Bycatch. Available at https://oap.ospar.org/en/ospar-assessments/intermediate-assessment-2017/biodiversity-status/marine-mammals/harbour-porpoise-bycatch/ [Accessed on 12.07.2024].Scottish Government, 2021. UK Dolphin and Porpoise Conservation Strategy: Technical Report. Published 22 March 2021. ISBN: 9781800048522. Available at https://www.gov.scot/publications/uk-dolphin-porpoise-conservation-strategy-technical-report/documents/ [Accessed on 12.07.2024].Species account by IUCN SSC Cetacean Specialist Group; regional assessment by European Mammal Assessment team. 2007. Phocoena phocoena. The IUCN Red List of Threatened Species 2007: e.T17027A6734714. Available at https://www.iucnredlist.org/species/17027/6734714 [Accessed on 12.07.2024].
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