Turbot

The spawning stock biomass of turbot in the North Sea is in a healthy state and is harvested sustainably.Stock assessments are carried out annually by the International Council for the 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.Spawning stock biomass (SSB) increased steadily from 2005 to 2018, and has since been in a gradual decline, but remains above MSY Btrigger (6,353 tonnes). In 2023, SSB is 6,882 tonnes and in 2025 it is predicted to increase to 7,223 tonnes.Fishing mortality in 2023 (0.30) is below FMSY (0.36) and has been in decline since 2021. Catches in 2022 and 2023 are the lowest in the times series (since 1981).ICES advises that when the MSY approach is appliced, catches in 2025 should be no more than 2,426 tonnes. This is an 18.2% increase from the previous year due to a bigger stock size at the beginning of the advice year and is derived from stronger recruitment in 2022-2023 compared to 2020-2021.

There is no management plan for turbot in the North Sea, but some measures are in place.Until 2024, turbot in the North Sea was managed under a combined total allowable catch (TAC) together with brill. ICES indicated that management of turbot and brill under a combined species TAC prevents effective control of the single-species exploitation rates which can result in high-grading and discarding of the lesser value species and overexploitation of the high value one, turbot. In 2024, a separate TAC has been given for turbot and brill. However, the TAC for turbot is for turbot in both ICES subarea 4 (North Sea) and division 2.a (Norwegian Sea).Catches are thought to consist predominantly of immature fish, which is having a negative impact on the potential yield from the stock. As turbot is a fast-growing species, reduction in the exploitation on younger ages would lead to an increase in maximum sustainable yield, supporting the need to reduce catching turbot under its length at maturity of between 30 and 35 cm for males and females respectively.Turbot is mainly a bycatch species in fisheries for plaice and sole. As such, fishing mortality for turbot is influenced by the management of plaice and sole fisheries.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 impacts Targets for fishing pressure and biomass, and additional management when those targets are not being met, based on the best scientific evidence Timeframes for stock recovery Improved 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 bycatch Stakeholder engagement A 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.Turbot is a valuable bycatch species in beam (48%) otter trawl (39%) and other (13%) fisheries for flatfish (plaice and sole) and other demersal species.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. As turbot 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.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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