Plaice

Pleuronectes platessa

Method of production — Caught at sea
Capture method — Gill or fixed net
Capture area — North East Atlantic (FAO 27)
Stock area — English Channel (West)
Stock detail — 7e
Picture of Plaice

Sustainability rating three info

Sustainability overview

Updated: July 2020.

The plaice stock in the Western English Channel is in a good state and fishing pressure is just above sustainable levels (FMSY). A single catch limit is in place for both Eastern and Western English Channel plaice. Plaice is caught in a mixed fishery targeting sole, with 80mm mesh size. This leads to a large number of plaice being discarded because this mesh size is not matched to the lower size limit for plaice. Gillnets in this area can encounter bycatch of non-target fish, mammals and birds. Reports indicate that there is concern regarding the bycatch of cetaceans, particularly harbour porpoise. 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. However, these reports are based on highly uncertain data which cannot indicate the likelihood of bycatch either causing populations to decline or preventing populations from recovering. Progress on this issue is being made in some areas.

Biology

Plaice is a bottom-dwelling flatfish. It spawns in the early months of the year (January to March) and sometimes makes long spawning migrations. North Sea plaice reach between 35 and 45 cm in their 6th year. It is a long-lived species, becoming sexually mature at 3-7 years (females) 2-6 (males) and living 30 years or more. Maximum reported age 50 years.

Stock information

Criterion score: 0.25 info

The plaice stock in the Western English Channel is in a good state. Fishing mortality (F) declined substantially after 2007, but has increased again since 2015 and in 2019 it was 0.58 – above the proxy for FMSY (0.48), but below the value for Flim (1.78) and Fpa (1.27). The spawning-stock biomass (SSB) has increased substantially since 2008, and in 2019 was 1.63, well above the proxy for MSY Btrigger (0.67). However, it has been decreasing since 2016 and is projected to be 1.49 in 2020. Recruitment has been in continuous decline since 2015 and is below the long-term geometric mean since 2017.

ICES advises that when the precautionary approach is applied, catches of the Western Channel plaice stock in 2021 should be no more than 2177 tonnes. This is a decrease on last year’s advice by 20% due to a decline in the stock index, however, as the precautionary buffer has been applied in 2019 for the 2020 advice, it has not been applied again this year.

Management

Criterion score: 0.5 info

This stock is covered by the EU’s Western Waters Multi Annual management Plan (MAP). The stock unit (Division 7.e) does not correspond with the management unit (Divisions 7.d and 7.e), and this hampers the effective management of plaice in the Western English Channel. This stock (7.e) is the smaller of the two plaice stocks that make up the larger total allowable catch (TAC) area (7.d-e). The official landings from this stock amounted to 15% of the TAC in 2019. The combined catches of plaice in 7.d-e accounted for 50% of the TAC in 2019. The TAC for this management area has not always followed scientific advice for divisions 7.d and 7.e, in 2016 it was doubled compared to 2015 but it has been reduced in recent years.

In this area, there is a mixed fishery for sole and plaice and the two stocks are dominant commercially caught species. The catch advice for plaice was a reduction by 25% for 2020 compared to 2019 and another 20% for 2021 compared to 2020 (preliminary). However, for sole, the catch advice increased by 16% (2020 vs. 2019) and 30% (preliminary, 2021 vs. 2020). Therefore, there are contrasting changes recommended for sole and plaice by ICES which could lead to higher catches including discards of plaice which should be closely monitored and might cause a negative trend for plaice stock.




The UK is due to leave the EU on 31st December 2020, and new UK Fisheries legislation is being developed during 2020. MCS will update ratings with new management information when new legislation comes into force.

In the European Union (EU), EU fishing vessels can fish up to 12 nautical miles of any Member State coast, and closer by agreement. There is overarching fisheries legislation for all Member States, but implementation varies between fisheries, Member States and sea basins.
The EU Common Fisheries Policy (CFP) is the primary overarching policy. Its key environmental objectives are to restore and maintain harvested species at healthy levels (above BMSY), and apply the precautionary and ecosystem-based approaches to fisheries management. To achieve the MSY objective, the MSY exploitation rate is supposed to be achieved by 2020, but this seems unlikely to happen.
The CFP also introduced a Landing Obligation (LO) which bans the discarding at sea of species which are subject to catch limits. Some exemptions apply to species with high post-capture survival, and where avoiding unwanted catches is very difficult. These exemptions are outlined in regional discard plans. Despite quota ‘uplift’ being granted to fleets under the LO, available evidence suggests there has been widespread non-compliance with the policy, and illegal and unreported discarding is likely occurring.
Multi-Annual Plans (MAPs) are a tool for implementing the CFP regionally, with one in place or being developed for each sea basin. They specify fishing mortality targets and ranges for the main targeted species, as well as lower biomass reference points. If populations drop below these points it should trigger a management response. The MAPs also empower Member States to jointly apply measures such as closures, gear or capacity limits, and bycatch limits. There is concern however that the MAPs do not provide adequate safeguards to maintain all stocks at healthy levels.
The EU Technical Measures regulation addresses how, where and when fishing can take place in order to limit unwanted catches and ecosystem impacts. There are common measures that apply to all EU sea basins, and regional measures that vary between sea basins. Measures include Minimum Conservation Reference Sizes (MCRS, previously Minimum Landing Sizes, MLS), gear specifications, mesh sizes, closed areas, and bycatch limits.
The Control Regulation, which is being revised in 2019, addresses application of and compliance with the above, e.g. keeping catches within limits, recording and sharing data, and satellite tracking of vessels over 12 metres (VMS).

Capture Information

Criterion score: 0.5 info

In 2019, 74% of the landings were taken by beam trawls, 19% by otter trawls, 3.4% by gillnets and 3.3% by other gear types gillnets.

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. 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. However, these reports are based on highly uncertain data which cannot indicate the likelihood of bycatch either causing populations to decline or preventing populations from recovering. Progress on this issue is being made in some areas, with Defra leading work to improve monitoring and mitigation of cetacean bycatch (“Hauling Up Solutions”). A pilot project trialling self-reporting of bycatch is taking place in Cornwall, potentially backed up by electronic monitoring and VMS in time, and trialling the use of pingers and other mitigation technologies, which are known to deter harbour porpoise from entanglement in nets. 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.

Alternatives

Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Dab
Halibut, Atlantic (Farmed)
Megrim
Plaice
Sole, Dover sole, Common sole
Turbot (Farmed)

References

ASCOBANS, 2009. Conservation Plan for Harbour Porpoises in the North Sea as adopted at the 6th Meeting of the Parties to ASCOBANS, Bonn, Germany. 16 - 18 September 2009. Available at https://www.ascobans.org/sites/default/files/document/ASCOBANS_NorthSeaPlan_MOP6.pdf [Accessed on 14.07.2020].

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 14.07.2020].

EU. 2019. Regulation (EU) 2019/472 of the European Parliament and of the Council of 19 March 2019 establishing a multiannual plan for stocks fished in the Western Waters and adjacent waters, and for fisheries exploiting those stocks, amending Regulations (EU) 2016/1139 and (EU) 2018/973, and repealing Council Regulations (EC) No 811/2004, (EC) No 2166/2005, (EC) No 388/2006, (EC) No 509/2007 and (EC) No 1300/2008. Official Journal of the European Union, L 83: 1– 17. http://data.europa.eu/eli/reg/2019/472/oj. [Accessed on 14.07.2020].

ICES, 2018. ICES Advice: Bycatch of small cetaceans and other marine animals - review of national reports under Council Regulation (EC) No. 812/2004 and other information. Published 11 September 2018. Available at https://www.ices.dk/sites/pub/Publication%20Reports/Advice/2018/2018/byc.eu.pdf [Accessed on 14.07.2020].

ICES. 2017. Report of the Workshop to consider FMSY ranges for stocks in ICES categories 1 and 2 in Western Waters (WKMSYREF4), 13–16 October 2015, Brest, France. ICES CM 2015/ACOM:58. 187 pp. https://doi.org/10.17895/ices.pub.5348. [Accessed on 14.07.2020].

ICES. 2020. Plaice (Pleuronectes platessa) in Division 7.e (west English Channel). In Report of the ICES Advisory Committee, 2020. ICES Advice 2020, ple.27.7e. https://doi.org/10.17895/ices.advice.5874. [Accessed on 14.07.2020].

ICES. 2020. Working Group for the Celtic Seas Ecoregion (WGCSE). Draft report. ICES Scientific Reports. 2:40. Xx pp. http://doi.org/10.17895/ices.pub.5978. Publication of the full report is expected end of 2020. [Accessed on 14.07.2020].

Northridge, S., Kingston, A., Mackay, A. and Lonergan, M. (2011). Bycatch of Vulnerable Species: Understanding the Process and Mitigating the Impacts. Final Report to Defra Marine and Fisheries Science Unit, Project no MF1003. University of St Andrews. Defra, London, 99pp. Available at http://randd.defra.gov.uk/Document.aspx?Document=MF1003-FINALRevisedAugust2011.pdf [Accessed on 14.07.2020].

Sustainable Fisheries Partnership (SFP). FishSource profile: European plaice Eastern English Channel. Available at https://www.fishsource.org/stock_page/ [Accessed on 14.07.2020].

Tindall, C., Hetherington, S., Bell, C., Deaville, R., Barker, J., Borrow, K., Oakley, M., Bendall, V., Engelhard, G. (Eds), 2019. Hauling Up Solutions: Reducing Cetacean Bycatch in UK Fisheries. Final Workshop Report. 31 pp. Available at https://www.cefas.co.uk/media/201924/hauling_up_solutions-workshop-report-final_web.pdf [Accessed on 14.07.2020].