Atlantic halibut

Northeast Atlantic halibut is a data limited species, leading to concern for fishing pressure. There is also concern for biomass due to the lack of data, and an indication of recruitment failure within the region.Route 2 (data limited) scoring has been applied to this rating due to a lack of reference points for fishing pressure and biomass. Atlantic halibut is classed as Vulnerable in Europe (last assessed in 2013) and Near Threatened globally (last assessed in 2021). Atlantic halibut have a very low resilience to fishing pressure and it is likely that they are overfished in European waters. Due to the lack of available data there is concern for fishing pressure.Atlantic halibut stocks in the Northeast Atlantic are not currently assessment by ICES, and research at local or national levels remains very limited. A report published by Iceland in 2025 highlighted sharp declines in biomass and recruitment between 1985 and 1990, with stocks reaching a historic low from 2008 to 2014. Biomass dropped from 5913 tonnes in 1985 to just 150 tonnes in 2012. In the past five years (2020-2025), biomass has recovered slightly above the historic low, with 2025 estimates of 1898 tonnes. However, recruitment has continued to decline over the last two decades, and with ongoing recruitment failure, the stock is expected to remain at low levels in the near future despite reduced catches. Due to a lack of data, and indications that Atlantic halibut stocks remain at low levels across the Northeast Atlantic, there is concern for biomass.

Management of Atlantic halibut in this region remains minimal. Without significant improvements in understanding stock status, effective management cannot be implemented. While no quotas are in place, directed fishing of Atlantic halibut is prohibited in Iceland.In the Northeast Atlantic, there is currently no widespread management measures for halibut. Without stock assessments, it is difficult to determine the status of the population or whether current fishing levels are sustainable, so appropriate management cannot be implemented.After a prolonged decline in Atlantic halibut stocks around Iceland, all directed fishing for the species was prohibited in 2012. As halibut remain a bycatch species in many fisheries, there is a requirement to release any capture individuals if they are considered fit for survival.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

Otter trawls are likely to cause some damage to the seabed. Bycatch in otter trawling is moderate and may include some vulnerable species.Demersal otter trawls have the potential to take relatively high quantities of bycatch, including those of conservation concern. In the Greenland Sea and Icelandic Waters ecoregions, bycatch from otter trawls can include marine mammals, seabirds, fish, elasmobranchs, and endangered, threatened and protected (ETP) species.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 instance, regions that are used to tidal and wave disturbances are less sensitive, whereas areas untrawled areas may be more vulnerable. Trawl gears are known to have some of the greatest impacts on Vulnerable Marine Ecosystems (VMEs). In this region, evidence shows that trawling activity overlaps with sensitive habitats such as cold water corals, sponges and sea pens, particularly around Greenland.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, The Marine Conservation Society would like to see remote electronic monitoring (REM) with cameras implemented, used and enforced.

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