Atlantic cod

Scientific advice recommends zero-catch for the Viking substock of Northern Shelf cod in 2026, this advice is now being followed. This results in a critical fail, and the rating is a default red.In 2023, ICES carried out a benchmark of two cod stocks: North Sea, eastern English Channel and Skagerrak, and West of Scotland. As a result, the understanding of the stock structure has changed substantially. These two stocks were merged into one: North Sea, West of Scotland, eastern English Channel, and Skagerrak. However, this new stock has three substocks:Northwestern: West of Scotland (6a) and western part of the Central (4b) and Northern (4a) North SeaViking: the Skagerrak (3a.20) and the eastern part of the Northern (4a) and Central (4b) North SeaSouthern: the southern part of the Central (4b) North Sea and all of the Southern (4c) North Sea, and the Eastern English Channel (7d)As a result, the perception of these new substocks is different from previous years and is not comparable to previous advice, before the 2023 benchmark.There is some uncertainty in the new stock assessments and ICES has indicated that catches by substock should not be taken as area-specific advice. The three substocks have different spawning grounds and biological characteristics, such as growth and time of sexual maturity. During spawning season and when the cod are young the substocks are not believed to mix, therefore it is possible to assess spawning stock biomass for each individual substock. However, they do mix at other times of year and further research and genetic data is needed to improve estimates of fishing mortality and provide specific catch advice.Overall, ICES is confident that there are three substocks, and that they can estimate their individual biomass sizes, but cannot accurately estimate catches or fishing mortality at the substock level.In 2023, the observed catches for all substocks combined were 14% lower than the ICES estimates, compared to 2022 where they were 33% lower.This rating is for the Viking substock.This stock is assessed by the International Council for the Exploration of the Sea (ICES). 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 (GFG) applies its own definition of 1.4 x MSY BTrigger.In 2023, the fishing pressure (F) was 0.26: 38% above the level associated with Maximum Sustainable Yield, FMSY (0.187), but below the precautionary limit (Fpa, 0.307). The total estimated catch was 9,255 tonnes. Therefore, estimated fishing pressure is too high and the substock is subject to overfishing.In 2024, the reproductive capacity of the stock - or spawning stock biomass (SSB), was 14,031t: below the GFG estimate of BMSY (19,224t) but 2% above the biomass trigger point, MSY Btrigger (13,732t). In 2023, SSB (12,840t) was below MSY Btrigger (15,098t). Therefore, the substock is fully fished.Because of the uncertainty about how much the substocks are mixing, ICES have advised a precautionary approach to protect the weakest substock (southern). ICES advises the Northwest and Viking substocks to follow the MSY approach with precautionary considerations. Under these approaches, catches in 2025 should be no more than 19,321 tonnes total, which corresponds to 12,158 tonnes from the northwestern substock, 4,089 tonnes from the Viking substock, and 3,074 tonnes from the southern substock.This is a 22% decrease in advice for the Viking substock due to the downscaling of the stock size, and lower income recruitment that previously estimated.If the advice is followed (MSY approach with precautionary considerations), the Viking substock’s SSB will increase by 25% to 22,034t, which would be above the GFG estimate for FMSY (19,224t). If fishing pressure remains the same as 2024, SSB will decrease by 4.3% to 16,856t.Atlantic cod is listed by OSPAR as a threatened and/or declining species. Recruitment of young fish into the stock has been poor since 1998. This is likely owing to a combination of long-term overfishing, which reduced the stock to low levels, and rising sea temperatures. North Sea surface temperatures have increased by 1.68 degrees since 1960. Further increases are expected, and predictions indicate that the North Sea stock is unlikely to recover substantially as a result.Between 1975 and 2005, the size at which cod matures reduced from around 75cm to 45cm. This is likely to be, in part, fisheries-induced evolution, especially for male cod. Rising temperatures are also a factor, especially for female cod.

Cod populations in this area have historically been highly depleted. A series of recovery measures have reduced fishing pressure to an extent, but it remains above sustainable levels. Catches have exceeded scientifically advised limits, and juvenile fish have not been protected.In 2023, ICES carried out a benchmark of two cod stocks: North Sea, eastern English Channel and Skagerrak, and West of Scotland. As a result, these two stocks were merged into one: North Sea, West of Scotland, eastern English Channel, and Skagerrak. There are now three sub-stocks: Southern, Viking, and Northwestern. Southern is below Blim, Viking is below MSY BTrigger and Northwestern is above MSY BTrigger. The perception of the new stock is different from previous years and is not directly comparable to previous advice. However, historically, management has not adequately controlled exploitation on West of Scotland and North Sea cod stocks, both of which were thought to be severely depleted (below Blim).Cod from these areas is caught by the UK, EU and Norway. For the North Sea stock, there has been an agreed management approach between all three parties. However, in the West of Scotland there has been no joint agreement. The stock is only covered as a bycatch species in the EU Multi Annual Plan for Western Waters (WWMAP), and the UK has had no management plan for it. It is too early to know how management will respond to the new advice.Historically, catch advice has not been followed. ICES has recommended zero catch for both stocks over the years: for West of Scotland from 2003-2022, and for North Sea from 2001 - 2007 and 2009. West of Scotland cod has mainly been caught as bycatch by trawlers targeting haddock, anglerfish, whiting and Norway lobster. A bycatch TAC was set in 2019 at 1,735t, dropping to 1,279t in 2020. Average catch for 2019-2020 was around 1,920t, 134% of the TACs. In the North Sea, managers allowed catches of around 35,000t during periods when there was 0 catch recommendation. Between 2018 and 2022, TACs exceeded recommended limits by an average of 14%. Catches averaged 109% of the TACs and 124% of the advice between 2017 and 2021. In both cases, management has not, therefore, followed scientific recommendations and has not adequately controlled the fishery.In the new assessment, ICES notes that substocks are mixed in catches, and there is not yet enough data to determine what proportions of each substock are present in different areas. Therefore, ICES has provided precautionary catch advice to protect the worst performing substock, Southern. The catch advice is specific to substocks but not to areas, because of the uncertainty about how substocks mix. This presents a challenge for management and suggests the need for a precautionary approach until there is more certainty. Future assessments are expected to have more data and may be able to provide area-specific catch advice.For 2025, the precautionary advice is 19,321 tonnes total, which corresponds to 12,158 tonnes from the northwestern substock, 4,089 tonnes from the Viking substock, and 3,074 tonnes from the southern substock.If all stocks were being fished at MSY, the advice would have been 29,693 tonnes, which corresponds to 18,272 tonnes from the northwestern substock, 7,310 tonnes from the Viking substock, and 4,111 tonnes from the southern substock. The total catch advice for 2024 was 22,691t, so the precautionary approach results in a 14.9% decrease for the fleet while the MSY approach leads to a 31% increase. This is also 38% lower than the combined 2023 TAC (31 301 tonnes) for the North Sea, West of Scotland, Skagerrak, and eastern English Channel.For 2024, predicted catches are 34% above the combined 2024 TAC for the entire stock area. The combined 2024 TAC is 31,301 tonnes which is 27.5% above the scientific advice, 22,691 tonnes. Therefore, management is not following scientific advice.Various other management measures have been applied to the North Sea and West of Scotland cod stocks over the years, including recovery plans and long-term management plans. In the North Sea there were considerable improvements in selectivity and cod avoidance. However, fishing effort was not reduced by enough for either stock. Management plans were discontinued when EU multi-annual plans (MAPs) were brought in in 2018.New measures were brought in in 2019 by the UK, EU and Norway to help the North Sea stock to recover. These appear to have been successful to an extent: the 2023 stock assessment shows a clear reduction in fishing pressure from 2019 and increase in biomass from 2020/21. However, F remains above FMSY for all three substocks. These plans have not included targets or timelines for reduction of fishing pressure or recovery of biomass. Therefore, they were not precautionary recovery plans, and were not appropriate for supporting recovery of a highly depleted stock.Measures in 2023 include the UK Cod Avoidance Plan and the EU Fishing Opportunities regulation (2023/1324):Closed areas for all or part of the year in Norway, the EU and the UK to protect spawning and juvenile cod.A minimum mesh size to reduce catches of juvenile cod (120mm in UK waters). There are exemptions for trawling in mud, where smaller meshes are used to catch Norway lobster. This reduces the effectiveness of these measures because such trawls often have a high bycatch of cod.Real time closures, where catches of high numbers of small cod trigger a closure of the area to fishing for a certain period.There are some additional closures to protect spawning cod. An area north of Scotland, known as the Windsock, was closed to fishing in 2003, but removed in 2019. It was replaced by the West Shetland Shelf MPA, and parts of the area were reopened to trawling. There is a voluntary agreement in place to restrict trawling on roughly 37% of the site, and during 2022 there were discussions to re-close a further portion of the MPA to trawling, but no further announcements have been made. An area of the Firth of Clyde has been closed from February-April since 2001. There were exemptions for creels, Nephrops trawlers and scallop dredgers but for 2022 and 2023 the closure was extended to all fishing gears because any fishing within 10 metres of the seabed may cause disturbance. Scottish Government are proposing to continue this closure in 2024 and 2025.There is a need to reduce fishing mortality on young cod, to allow more fish to reach maturity and grow the stock. This does not appear to have been achieved despite the above measures. Cod can legally be caught and sold at 35cm. Below this minimum size, cod must be landed but can't be sold for human consumption and so have a lower value. Cod mature at 45cm, so this does not discourage catching juveniles.In addition, and despite the landing obligation, many below-minimum-size cod are illegally discarded at sea. In the West of Scotland from 2016-2018, an estimated 70% (by weight) of the total catch was discarded. This reduced to 34% in 2021. From 2019-2021, juvenile cod (aged 1-3) were 75% of the catch by number, and 98% of the discards.In the North Sea from 2017-2021, 17% of the total catch by weight was discarded. By number, 83% of the total catch was juvenile cod.Some misreporting has taken place, with cod caught in 6a (West of Scotland) being reported in 4a (North Sea) and 5b (Faroes). In 2018, around 60% of the landings in 6a were misreported as 4a or 5b, reducing to 30% in 2019 and 5% in 2021. These estimates can't be verified by vessel tracking data because there have been issues with accessing UK data.In the North Sea, recreational catches may account for around 5% of total removals. They aren't well recorded, so aren't included in assessments. There are no catch limits. Cod is also caught as bycatch in many fisheries, and better mixed fishery management is needed to ensure that this doesn't put unsustainable pressure on the stock. 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 Atlantic Cod FMP has been proposed, coordinated by Marine Scotland 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 cod catches are by otter trawls, which are likely to cause some damage to the seabed. Bycatch is moderate and may include vulnerable species such as blue and flapper skate. There may also be bycatch of cod from the more vulnerable Southern substock.ICES carried out a benchmark in 2023, which resulted in two cod stocks being merged in to one: North Sea, West of Scotland, eastern English Channel, and Skagerrak. This stock was further divided into three substocks.The Viking substock encompasses areas in the Skagerrak (3a.20) and the eastern part of the Northern (4a) and Central (4b) North Sea.Otter trawlers interact with the seabed and can modify bottom topography and cause damage and removal of some biogenic features including vulnerable marine habitats and benthic communities. They can also bycatch vulnerable species.Most cod throughout the Northern Shelf (around 81%) are caught by demersal trawls and seines. This includes demersal trawls and seines with large mesh size (100mm +) (74%) and small-meshed trawls targeting Nephrops (7.5%). Around 10% of the catch is from gillnets and 2.5% from beam trawls.Cod throughout the Northern Shelf are a part of a mixed fishery with haddock, Nephrops, whiting, plaice, sole, turbot, brill, and saithe. Cod is the most limiting stock for demersal fisheries in this region, meaning the cod quotas are met with quicker and lower effort compared to the other fisheries.Additionally, because there is some mixing between the three substocks, though further research and genetic data is needed to determine the degree of mixing, there may be bycatch of cod from the Southern substock. The Southern substock is the most vulnerable of the three and it is possible that bycatch levels of this substock is impacting the population recovery.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.Some mitigation measures are in place in some areas. For blue and flapper skate, these include a prohibition on landing either species, in addition to 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, the Marine Conservation Society considers it possible that the bycatch level is contributing to population decline and/or preventing recovery. Additionally, a proportion of the trawl fisheries in the North Sea are Marine Stewardship Council-certified and record bycatch. The Marine Conservation Society assumes these records would also represent bycatch concerns in uncertified fisheries in the area. Bycatch in the certified fishery includes the Critically Endangered common skate complex (blue skate and flapper skate), porbeagle, and other skates and rays.Otter 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).In the North Sea impacts from bottom trawling are variable. Fishing grounds for cod 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 - 2021 indicates that trawling was happening on 85% of the seabed area in the North Sea. Fishing effort has been decreasing since the early 2000’s, 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). Additionally, compared to unfished levels in the North Sea there has been approximate decrease of 20% of invertebrate benthic biomass due to physical disturbances from fishing. Impacts may be as high as 90% in the most heavily fished areas.Mitigation measures include a ban on bottom trawling below 800m, and restrictions from 400-600m – the areas where most VMEs are found. There remains some uncertainty about the location of some sensitive seabed habitats, so these remain at risk.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, the Marine Conservation Society 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, the Marine Conservation Society 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. 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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