Dover sole

Stock Status Score: 0

Sole in the western English Channel is fully fished and harvested sustainably.

Stock assessments are carried out by the International Council for Exploration of the Sea (ICES). This rating is based on the assessment published 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 a peak in 1980 before fluctuating around MSY Btrigger (2,900 tonnes) from the early 1990s to 2009. The stock then increased steadily, reaching a second peak in 2020, before declining in recent years. In 2026, SSB is estimated at 3,762 tonnes, which is above MSY Btrigger but below the BMSY proxy (4,060 tonnes). The stock is therefore considered to be fully fished.

Fishing mortality (F) increased during the 1980s and remained around or above FMSY (0.29) for much of the early time series. Fishing pressure declined between 2009 and 2020, remaining below FMSY throughout this period, but increased again from 2021 to 2024. In 2025, F was estimated at 0.28, just below FMSY, indicating that the stock is currently being harvested at a sustainable level.

ICES advises that when the MSY approach is applied, catches in 2027 should be no more than 1,017 tonnes. This is a 16.2% decrease in advice from the previous year, which reflects a decline in the stock and a downwards rescaling of stock size.

Management of the Target Stock Score: 0

Alignment with Scientific Advice Score: 0.5

Monitoring, Control and Surveillance Score: 0.25

Sole in the western English Channel is well managed through a combination of the Landing Obligation, minimum conservation reference sizes, and technical measures. Although catches exceeded scientific advice once in the past five years, they remained below advised limits in the most recent year. The fishery has a well‑developed and effective Monitoring, Control, and Surveillance (MCS) system with reliable enforcement and low levels of IUU activity.

The sole fishery in the western English Channel is managed through Total Allowable Catches (TACs) and a range of technical measures. While the stock is covered by the EU Multiannual Plan (MAP), there is currently no joint management plan agreed between the EU and the UK.

Sole is caught in a mixed fishery with plaice in this area. Fishing mortality for both species is affected by technical management measures, including gear selectivity requirements and mesh size regulations. The current UK technical gear measures are as follows:

• Beam Trawls: 80mm mesh cod-end.
• Otter Trawls: 100mm mesh cod-end, with 100mm square mesh panel (exception for area east of 5°W).
• Nets: 100mm mesh size.

Sole in the western English Channel has been subject to the Landing Obligation (LO) since 2020. The LO was introduced to improve catch reporting, reduce unwanted catches, and encourage more selective fishing practices. However, some exemptions apply to this fishery, including de minimis exemptions for beam trawls fitted with Flemish panels and for gill and trammel net fisheries, allowing certain catches to be returned to sea. A minimum conservation reference size (MCRS) of 24 cm applies throughout the fishery. Discard rates remain relatively low, averaging 0.4% annually between 2020 and 2022, with a slight increase to 2.8% in 2025.

The stock is managed through a total allowable catch (TAC) system. Between 2020 and 2026, TACs were set in line with ICES catch advice in all years except 2024. As a result, catches in 2024 reached 111% of the advised limit. In 2025, the TAC was again aligned with ICES advice at 1,151 tonnes, while catches remained below this level at 1,052 tonnes (91.4% of the TAC).

The western English Channel sole fishery overlaps with both the Celtic Seas and Greater North Sea ecoregions, where sole forms part of mixed demersal fisheries. ICES notes that, under current fishing patterns, it is not possible to simultaneously achieve all single-stock catch advice within either ecoregion, due to choke species like cod, haddock, and whiting. Therefore, choke species are largely overlooked. However, the interaction between sole fisheries and these species is considered limited.

Sole is more commonly caught alongside plaice, which is not included in the mixed-fishery advice. Given that the plaice stock in this area has declined substantially over the past decade and has remained below the MSY Btrigger proxy (Itrigger) since 2019, any changes in sole fishery management or fishing effort could influence plaice catches and potentially affect the stock's recovery.

Monitoring, control and surveillance of UK fisheries are delivered through licensing, vessel tracking, statutory reporting, observer coverage, inspections and other monitoring systems. All commercial fishing vessels must hold a valid UK fishing licence to operate in UK waters, although exemptions may apply to some unpowered vessels under 10 metres. Depending on the area, target species and activity, additional permits or authorisations may also be required.

Vessel tracking requirements vary by vessel size, area and administration through Vessel Monitoring Systems (VMS) and, where applicable, inshore VMS (iVMS).

• Vessels 12 m and over must report their position every two hours via VMS.
• Vessels under 12 m report their position continuously where iVMS applies, or may operate full VMS where required by licence conditions or when fishing offshore.

Reporting of fishing activity, catches, landings, discards and port movements is mandatory, with logbooks supporting traceability:

• Vessels 12 m and over submit electronic logbooks under Council Regulation 1224/2009.
• Vessels 10–12 m (and under 10 m Producer Organisation vessels) use paper logbooks, updated daily and submitted within 48 hours of landing.
• Non-PO vessels under 10 m are generally exempt unless required by licence conditions.

UK vessels must also carry fishery observers when directed, providing independent verification of activity and catch. Remote Electronic Monitoring (REM), using cameras, sensors and positional data, is being increasingly deployed to improve data quality and support enforcement. Its rollout is supported by the Fisheries Act 2020 and the Joint Fisheries Statement.

Together, these measures help prevent illegal, unreported and unregulated (IUU) fishing through vessel licensing, catch documentation, positional monitoring, statutory reporting and compliance checks. Enforcement action may include financial penalties, prosecution, licence suspension or other sanctions. The UK has committed to reducing IUU fishing and maintains a blacklist of vessels involved in such activities. This rating reflects full compliance with UK monitoring, control and surveillance requirements.

The Marine Conservation Society views Remote Electronic Monitoring (REM) with cameras as 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. 

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 Celtic Sea and Western Channel demersal FMP has been proposed, coordinated by Defra and the Welsh 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]. 

Capture Method Score: 0.75

Habitat Impacts: 0.75

Bycatch Impacts: 0.5

Vulnerable and ETP Species: 0.75

Ecosystems and Trophic Webs: 0.25

Beam trawls have significant impacts on the seabed, including damage to benthic communities and vulnerable marine habitats. Although interactions with zero-catch gadoid stocks are limited in this mixed demersal fishery, bycatch of plaice may be affecting the stock's recovery. This gear type can also interact with ETP species. While sole landings have remained stable, beam trawling may continue to exert pressure on an ecosystem already affected by historic fishing.

The majority of western English Channel sole landings come from beam trawls (68%), followed by otter trawls (18%), gillnets (9%), and other gears (5%). In 2025, total catches were 1,053 tonnes.

Beam trawling, particularly with chain-mat gear, can significantly impact benthic communities. Demersal trawls make direct contact with the seabed, causing penetration and abrasion of habitat features. The extent of seabed impact depends on gear type, sediment composition, and the area's natural resilience. For instance, regions that are used to tidal and wave disturbances are less sensitive, whereas areas untrawled areas may be more vulnerable. Beam trawls typically penetrate the seabed between 1cm and 8cm, with heavier gear causing greater disruption than otter trawls.

In the Greater North Sea and Celtic Seas ecoregions, impacts from bottom trawling are variable. Most fishing grounds consist of mud and sand, which are less susceptible to damage than habitats like reefs and seagrass beds. In 2022, it was estimated that 66% of the Greater North Sea and 61% of the Celtic Seas seabed shallower than 800m was trawled.

There are several Marine Protected Areas (MPAs) within the western English Channel that are designated to protect sensitive benthic habitats and species that may be vulnerable to bottom-towed fishing gears. Restrictions on bottom-towed gears are already in place in some areas, including South Dorset Marine Conservation Zone (MCZ). However, protection across the MPA network remains incomplete, with several sites only recently being considered through the MMO's Stage 3 byelaw process. As such, some designated features may remain exposed to disturbance from bottom trawling, potentially limiting habitat recovery and the achievement of conservation objectives. Given the critical role MPAs play in recovering marine health and supporting ecosystem function, the Marine Conservation Society urges supply chain actors to verify whether their sources originate from within MPAs. If so, businesses should confirm that fishing operations are legally conducted and request evidence from the fishery or managing authority to ensure activities do not harm protected features or compromise conservation objectives.

Beam trawls have the potential to take relatively high quantities of bycatch, including those of conservation concern. In both ecoregions, bycatch from beam trawls can include marine mammals, seabirds, fish, elasmobranchs, and endangered, threatened and protected (ETP) species.

Although monitoring of bycatch across UK and EU fisheries remains limited, available research indicates that beam trawls in the Greater North Sea ecoregion are responsible for the annual bycatch of approximately 102 grey seals, 453 northern gannets and 2,909 short-snouted seahorses. While all three of these protected species are currently classified as Least Concern on the IUCN Red List, short-snouted seahorse populations are declining, with fishing-related bycatch recognised as a significant threat. In the Celtic Sea, trawl fisheries also interact with several elasmobranch species of conservation concern, including the prohibited common skate complex. Although these bycatch estimates cannot be attributed directly to the western English Channel sole fishery, they demonstrate that beam trawl gear can affect vulnerable and protected species, and therefore its impacts cannot be considered negligible.

Sole is caught as part of a mixed fishery within the Greater North Sea and Celtic Sea ecoregions. In the Celtic Sea region, cod, haddock, and whiting are choke species as they are subject to zero-catch advice. However, these species may still be bycaught within the sole fishery. That said, catches of these species have declined steadily over the past decade, and beam trawls accounted for only 4–11% of their landings in 2025. Consequently, interactions between the sole fishery and these stocks are considered limited, and the fishery’s direct contribution to the bycatch and associated impacts on stock recovery of these species is likely to be limited.

More common bycatch species in this fishery include anglerfish, plaice, lemon sole, and cuttlefish. Plaice discard rates in the western English Channel are high, averaging an estimated 34% between 2012 and 2024, largely as a result of gear selectivity and the minimum conservation reference size (MCRS), however the assessment does assume a 50% survival rate for discarded fish. The stock's biomass has declined since 2014 and has remained below the MSY Btrigger proxy (Itrigger) since 2019. Beam trawls account for the majority of both plaice landings (71%) and discards (76%) in the area, indicating that the sole beam trawl fishery is likely to have a significant influence on plaice stock stability. Consequently, any increase in fishing effort or changes in management measures within the sole fishery could affect plaice mortality and potentially hinder stock recovery.

Sole occupy a mid-trophic-level position in the food web, feeding mainly on benthic invertebrates and serving as prey for larger fish and marine mammals. The English Channel ecosystem has changed considerably over the past century, reflecting a pattern of “fishing down marine food webs”. Since the 1920s, higher-trophic-level species such as gadoids and elasmobranchs have declined, while lower-trophic-level invertebrates have become more prominent in landings. The loss of top predators can have cascading effects on food-web structure and ecosystem functioning.

Despite these broader ecosystem changes, landings of western English Channel sole have remained relatively stable at around 1,000 tonnes since the early 2000s. However, sole is primarily caught using bottom trawls, which can cause seabed disturbance and generate multi-species bycatch. Consequently, habitat alteration and incidental catches may continue to exert pressure on an ecosystem that has already been substantially modified.