Atlantic halibut

Northeast Atlantic halibut is a data-limited species. Available data indicates increasing catch levels, leading to concern for fishing pressure. There is also concern for biomass.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.Catches of halibut by Norway have risen significantly, from 676 tonnes in 2002 to 3768 tonnes in 2023. A decline occurred between 2019 and 2020, with catches dropping from 3216 tonnes to 2405 tonnes, likely due to the Covid-19 pandemic. However, this quickly rose again to 3027 tonnes in 2021, and 3508 tonnes in 2022. The overall increase in catch is thought to reflect greater fishing effort in recent years, driven by the use of adapted longlines and more vessels entering the fishery. The combination of rising catch levels, and a lack of formal assessments and reference points for the fishery, leads to concern for fishing pressure.With no formal stock assessments of Atlantic halibut in Norwegian waters, biomass levels are unknown relative to sustainable reference points. Research indicates that stock levels fluctuate annually, with only populations in northern waters are considered in ‘good’ condition. Given the fragile state of the stock, and evidence from the wider Northeast Atlantic showing low biomass and recruitment failure, concern remains for stock biomass in Norway.

Management of Atlantic halibut in this region remains minimal. Without significant improvements in understanding stock status, effective management cannot be implemented. While a minimum landing size is in place, it is below maturity estimates.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.In Norway, there is a minimum landing size (MLS) of 84cm in place. However, halibut are estimated to reach maturity between 104-140cm. This means that many individuals are likely caught before reproducing, which can undermine stock stability. There is also a requirement to discard halibut over 200cm, but not for conservation purposes. Instead, it is due to the accumulation of contaminants making them unsafe to eat. Additional regulations include mesh size restrictions – 130mm north of 64˚N, and 120mm south of 64˚N. There is also a closed spawning season from 20 December to 20 April across the entire Norwegian economic zone.Despite these measures, effective management is hindered by a lack of biological information, particularly regarding population distribution, migration patterns, spawning behaviour, and other key characteristics.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 Norwegian Sea ecoregion, bycatch from otter trawls can include elasmobranchs, fish, and endangered, threatened and protected (ETP) species. Notably, both blue ling and golden redfish are taken as bycatch in bottom trawl fisheries, despite directed fisheries for these species being prohibited. Golden redfish is also classed as an ETP species, as it is listed as ‘Highly Endangered’ on the Norwegian Red List.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, it is estimated that 50% of the area of VMEs overlaps with bottom trawling, of which, 10% is subjected to relatively high fishing pressure.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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