Flounder

There is concern for the biomass of flounder in the North Sea, Skaggerak and Kattegat, and no concern for the fishing pressure.Route 2 (data limited) scoring has been applied to this rating owing to the lack of reference points for biomass and fishing pressure. Flounder has a medium resilience to fishing pressure.Stock assessments are carried out biennially by the International Council for the Exploration of the Sea (ICES). The most recent assessment was published in 2023 and the next assessment is expected in 2025.Flounder is mainly a bycatch species in the demersal fisheries in coastal areas of the North Sea. A survey biomass index is used as an indicator of flounder stock development. The stock size indicator is has been below Itrigger (22.899) since 2018 and in 2023 is 19.16. Therefore, there is concern for the biomass.Fishing pressure on the stock is below the FMSY proxy and therefore, there is no concern for fishing pressure.ICES advises that when the MSY approach is applied, catches in each of the years 2024 and 2025 should be no more than 864 tonnes. If discard rates do not change from the average of the last three years (2020-2022), this implies landings of no more than 640 tonnes in each of the years 2024 and 2025. This advice is a 48% decrease from the advice for 2023 due to a low index ratio.

There is no management plan for flounder in the North Sea, but there are some measures in place.Management of flounder in the North Sea is only partially effective. Flounder is a bycatch species in other flatfish fisheries for plaice and sole. It is generally considered underutilised and is commonly discarded due to low market value and demand. Discard rates can be high, ranging between 12% and 49% between 2002-2022. No minimum landing size is defined for flounder. However, flounder matures between 20-30cm and some regional authorities do have minimum landing sizes in force.Flounder was previously managed under a combined total allowable catch (TAC) together with dab. This was removed following ICES advice indicating the risk of having no catch limits for the dab and flounder stocks was considered to be low and not inconsistent with the objectives of the Common Fisheries Policy (CFP). As flounder is not subject to catch limits, it does not fall under the landing obligation.For plaice and sole fisheries, technical measures are in place in this area. These include:Mesh size regulations for towed trawl gears require that vessels fishing North of 55° (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.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.

Beam trawls have significant impacts on the seabed, including damage to benthic communities and vulnerable marine habitats. They can also have high bycatch, potentially of vulnerable species.Flounder in the North Sea, Skaggerak and Kattegat is not targetted commercially. It is commonly taken as bycatch by beam trawlers (76%), gillnets (11%), otter trawls (11%) and other gear types (2%).Beam trawls have the potential to take relatively high quantities of bycatch (more than 50% of catch weight), including those of conservation concern. In the North East Atlantic there are reported catches of demersal elasmobranchs and endangered, threatened and protected (ETP) species, such as 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. MCS assumes these records will be indicative of bycatch in the uncertified component. Bycatch includes the vulnerable North Sea cod, which is below safe reproductive 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.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, MCS considers it possible that the bycatch level is contributing to population decline and/or preventing recovery.Demersal trawls have contact with the seabed resulting in penetration and abrasion of habitat features. The impact of trawling on the seabed depends on the location and scale in which trawling occurs. For example, areas that are used to natural disturbance through tides and waves, are less sensitive to habitat impacts. Areas not used to mobile towed gears are typically more sensitive to trawling.Beam trawling, especially using chain-mat gear, is a high impact method of fishing and can have a significant impact on benthic communities. Heavy gear tends to have a higher seabed impact than otter trawling and seabed penetration can vary between 1cm and 8cm, depending on the sediment.In the North Sea area, impacts from bottom trawling are variable. Fishing grounds vary, but the habitat is generally mud and sand, which are less vulnerable to trawling than features such as reefs and seagrass. Data from 2018 indicates that trawling was happening on 73% of the seabed area. Fishing effort in the region has halved since 2002, mainly in the trawl fisheries, which is reducing pressure on the seabed and on bycatch species. However, fishing in the North Sea in general has reduced the number of large fish in the ecosystem (mostly cod, saithe, ling, sturgeon, and some elasmobranchs). There are concerns about the impact of North Sea trawling on sea pens.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).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.

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