Whiting

The whiting population in the West of Scotland is below target levels, but is not subject to overfishing.Catches of West of Scotland whiting have declined from over 20,000 tonnes in the 1980s to around 1,000t since 2005.Stock assessments are carried out annually by International Council for the Exploration of the Sea (ICES). The most recent stock assessment was published in 2025 using data up to 2025. The next assessment is expected in 2026.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) declined from over 100,000 tonnes in the 1980s to around 6,500t in the late 2000s. It was below the point of reproductive impairment (Blim), which is 17,286t, for most of the 2000s and early 2010s. SSB recovered to above MSY BTrigger (25,597t) in the early 2020s but has again declined slightly. In 2025 it was 19,372t, which is just below MSY BTrigger and Bpa (21,442t) but above Blim (17,286t). Therefore, the we consider the stock to be overfished.Fishing mortality (F) has reduced from very high levels of around 0.6 in the early 2000s to 0.030 in 2024. This is well below the level associated with Maximum Sustainable yield (FMSY, 0.21). The stock is therefore not subject to overfishing.ICES advises that when the MSY approach is applied, catches in 2026 should be no more than 5,364 tonnes. This is a 4.8% increase from the previous year's advice because of increased recruitment estimates for 2024. This is expected to lead to a 6.2% reduction in SSB between 2026 and 2027.

Some appropriate management measures are in place for West of Scotland whiting, but there is no specific management plan in place. Historically, the stock has been subject to significant overfishing. Recent management has been in line with scientific advice, but illegal discarding is still taking place.Catches of whiting in the West of Scotland are mainly by the UK, responsible for around 60-70% of the total. Most of the rest is taken by Ireland. Whiting is not generally targeted, but is caught as bycatch in other fisheries - mostly the whitefish (haddock, saithe, and anglerfish) and Norway lobster fisheries. The EU has a Multiannual Plan (MAP) for its fleets, which covers this species as bycatch, but the UK is not part of it. There is no agreed management approach between the EU and UK.Catch limits, known as Total Allowable Catches (TACs), are the main management measure. TACs are informed by annual stock assessments by the International Council for the Exploration of the Sea (ICES), and are divided between the catching countries. They have not historically been set in line with the scientific advice. From 2006-2021, scientific advice was for zero catch of the stock, but a TAC was still set and catches continued. Catches of whiting exceeded TACs from 2009-2021. From 2017-2021, catches averaged 1,250t, which was 300% of the average TAC. This indicates that compliance has been poor and management has not been adequately controlling the fishery.In 2021, the perception of this stock changed dramatically. Whereas it was previously thought to be below safe levels and in need of recovery, it is now thought that the population is close to target levels. While this is positive, it is not the result of good management. The management approach was not robust enough to handle the low-biomass situation. A plan with Harvest Control Rules, which include appropriate targets to reduce fishing pressure when stocks are low, is needed.However, catches have been below advice following the change in the perception of the stock, a more precautionary approach has been taken. The advice for 2024 was 3,879t with TACs set around 20% below that while catches were much lower then advice at 716t. The 2025 TAC (4,952t) has also been set below advice (5,116t). Therefore, TACs and catches are now partly following scientific advice. However, the TAC is set for a much larger area than just West of Scotland (area 6a). It includes areas 6b (Rockall), 5b (Faroes) and international waters of 12 (North of the Azores) and 14 (East Greenland). This prevents adequate control of the fishing pressure on individual stocks and therefore does not protect this stock from overexploitation.The minimum conservation reference size (MCRS) for whiting is 27cm. Below this size, saithe have to be landed but can't be sold for human consumption and so have a lower value.Since 2019 it has been illegal to discard unwanted (e.g. under-size or over-quota) whiting at sea. Almost no undersize whiting are reported in landings, and observers on boats estimate that illegal discarding is still taking place. This has historically been the result of small TACs. Since the TACs have been increased, discarding appears to be declining. The proportion of total catch discarded was 16% in 2022 and 17% in 2023, but increased to 62% in 2024 . However these are still much lower than the 2017-2020 average of 73%. In 2024, 80% of discards were by Norway lobster trawlers and 18% by finfish trawlers.In addition to the catch limits and the landing obligation, there are a number of technical measures to control fishing. Since 2010, the nets towed by trawlers must have a minimum mesh size of 120mm. Smaller mesh can be used if by-catches of cod, haddock and saithe do not exceed 20% of the total by weight, or there are selectivity measures in place. Trawlers targeting Norway lobster can use smaller meshes (79-99mm), but since 2008 they must use square mesh panels that can allow fish to escape the net. ICES notes that these measures did not reduce discards of whiting, but are likely to have contributed to reductions in overall fishing mortality.In 2015, the industry group GITAG (Gear Innovation and Technology Advisory Group) was established to focus on improving selectivity and support the transition to the landings obligation. A number of trials have been carried out, but it is unclear if or how these have been adopted into the wider fishery.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 West coast of Scotland whiting FMP has been proposed, coordinated by the Scottish Government, that incorporates this stock. At the time of writing, it is too soon to know whether 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].

Most whiting catches are by trawling, which is likely to cause some damage to the seabed. Bycatch is moderate and may include vulnerable species.Catches of whiting in the West of Scotland are mainly by the UK, responsible for around 60-70% of the total. Most of the rest is taken by Ireland. Whiting is not generally targeted, but is caught as bycatch in other fisheries - mostly the whitefish (haddock, saithe, and anglerfish) and Norway lobster fisheries.Demersal otter trawls have the potential to take relatively high quantities of bycatch. In the Northeast Atlantic there are reported catches of demersal elasmobranchs and endangered, threatened and protected (ETP) species (e.g. sharks, rays and marine mammals). Bycatch data is limited in many UK and EU fisheries as they are generally not well monitored. 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.Work is underway to trial selective gears and develop tools to reduce bycatch. In the west of Scotland, this includes BATmap (By-catch Avoidance Tool using mapping), launched in 2020. It allows real-time reporting of bycatch of cod and spurdog to identify areas for skippers to avoid. Work is ongoing to refine and roll it out further. Innovation such as this is a very positive and vital step forward for minimising bycatch in mixed fisheries.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. Trawl gears are known to have some of the greatest impacts on Vulnerable Marine Ecosystems (VMEs).Mitigation measures include a ban on bottom trawling below 800m, and restrictions from 400-600m – the areas where most VMEs are found. It is estimated that approximately 70% of seapen habitat in this area is closed to fishing, through inaccessibility to trawls or Marine Protected Areas (MPAs). There remains some uncertainty about the location of some sensitive seabed habitats, so these remain at risk.Some MPAs in this area 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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