Black-bellied monkfish

Stock Status Score: 0

Black-bellied anglerfish in the Celtic Seas and Bay of Biscay is not overfished and not subject to overfishing.

Stock assessments are carried out annually by the International Council for the Exploration of the Sea (ICES). The most recent assessment was published in 2026 using data up to 2026. The next assessment is expected in 2027.

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. 

The spawning stock biomass (SSB) in this area has increased overall from a low of around 10,997 tonnes in 2003 to 53,501 t in 2026. This is well above MSY Btrigger (16,776t) and the GFG proxy for BMSY (23,486 t). Therefore, the stock is not in an overfished state.

Fishing mortality (F) has been generally declining since 2013 from 0.21 to 0.103 in 2025. This is below levels associated with Maximum Sustainable Yield (FMSY: 0.163). The stock is therefore not currently subject to overfishing.

ICES advises that when the MSY approach is applied, catches in 2027 should be no more than 19,130 tonnes. This is a 14.6% reduction from the previous year’s advice due to the downward revision of the stock size.

Management of the Target Stock Score: 0.25

Alignment with Scientific Advice Score: 0.5

Monitoring, Control and Surveillance Score: 0.25

There is no management plan for black-bellied monkfish in the Celtic Seas (South) and Bay of Biscay, but some measures are in place, which are partly effective in managing the stock.

The EU multiannual plan (MAP) for stocks in in the Western Waters and adjacent waters applies to this stock. There is no agreed shared management plan with the UK for this stock. ICES precautionary approach is applied to catch advice. In 2022 reference points for black-bellied anglerfish were established for this Celtic Seas and Bay of Biscay stock using a category 1 assessment, providing more robust estimates of stock status and fishing pressure.

Management of the stock under a combined TAC (catches of two anglerfish species) prevents effective control of single-species exploitation rates and could lead to overexploitation of either species. Both species of monkfish, otherwise known as anglerfish: white anglerfish (Lophius piscatorius) and black-bellied anglerfish (Lophius budegassa), are taken in a mixed fishery, mainly with hake, megrim and Nephrops. The two anglerfish species are not totally separated in the landings, and landings are generally reported for the two species combined (L. piscatorius and L. budegassa). The combined landings are then split into species at a national level, based on the species composition in the sampling data. A single total allowable catch (TAC) covers both anglerfish species, and species-specific landings are estimated by ICES, whereby black-bellied anglerfish account for 41% of landings between 2021-2025, and white anglerfish make up the rest. ICES considers that management of catches of the two anglerfish species, under a combined species TAC prevents effective control of the single-species exploitation rates and could lead to the overexploitation of either species. However, currently the stock size of both species is increasing and neither species appears to be at risk of over-exploitation. Since 2019, the combined TAC has been set in line with advice. Compliance to the TAC is high, and according to ICES estimations, landings of both species together averaged consistently below the TAC and advice.

There is evidence of considerable potential for long-distance migration, and it is not clear whether this stock definition (Subarea 7, Divisions 8a-b, 8d) is appropriate. Because there is currently insufficient information to change the stock boundaries, the current stock definition remains unchanged. This presents a number of issues for management.

There is no minimum landing size for monkfish (anglerfish). Black-bellied anglerfish reaches maturity at around 65 cm, which corresponds to around 4-5 years. Consequently, these fish are being caught before they have had chance to reproduce. EU Council Regulation (No. 2406/96) laying down common marketing standards for certain fishery products fixes a minimum weight of 500 g for anglerfish.

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 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 

Capture Method Score: 1

Habitat Impacts: 0

Bycatch Impacts: 0.25

Vulnerable and ETP Species: 1

Ecosystems and Trophic Webs: 0.25

Bycatch of harbour porpoises in set-nets is occurring in the Bay of Biscay, to the extent that the local population of the species may become extinct.

Monkfish or black-bellied anglerfish is predominantly caught by beam trawling in the Celtic Seas and Bay of Biscay. Anglerfish are an important component of mixed fisheries, mainly caught with hake, megrim and Nephrops, but also sole, cod, and plaice. The fishery for anglerfish developed in the late 1960s. In recent years, France has taken the vast majority of black-bellied anglerfish (L. budegassa) landings; followed by Spain, Ireland and the UK. The majority of black-bellied anglerfish is consistently taken by demersal otter trawling, targeting demersal fish; accounting for 71% of catch. Gillnets (8%), beam trawls (11%) targeting demersal fish, and otter trawls targeting Nephrops (which tend to be further inshore and shallower) (7%), also contributed to catch. Black-bellied anglerfish are most abundant at depths of 200 - 500 m, and are taken both offshore and inshore. Juveniles are mainly found offshore in the western Celtic Sea and sometimes in the Bay of Biscay.

Anglerfish are targeted by gillnetters (using mesh size 120-219 mm) in the shallower Celtic Sea, where a large number of inshore gillnetters (<12 m) are active. Gillnet fisheries around the Irish coast target anglerfish seasonally. Prior to 2006, UK, French, German, and Spanish gillnetters operated in deep waters of Subareas 6 and 7, targeting anglerfish among other species. This fishery stopped or seriously reduced from 2006, following EU regulation of deep-water gillnetting at depths below 600 m. Fixed net fisheries, for anglerfish, in the Celtic Seas and Bay of Biscay have little to no impact upon the seabed. Gillnets and fixed nets can be very selective, but incidental catch (bycatch) of non-target species can occur. Gillnets cannot be specifically targeted to give clean catches of anglerfish and a wide range of other non-target species can become enmeshed, particularly in demersal set gillnets. Gillnets can bycatch species such as sharks, cetaceans and other marine mammals. In the Bay of Biscay, observation of marine mammal bycatch has occurred in certain fisheries off France and in a few off Galicia. Reports indicate that there is concern regarding the bycatch of cetaceans, particularly harbour porpoise, by gillnets. Endangered, harbour porpoises (Phocoena phocoena) are being caught as bycatch off Iberia, in set-nets to the extent that the local population of the species may become extinct. It is estimated that in the Celtic Seas (including the eastern Bay of Biscay) in 2017 between 536 - 1409 harbour porpoises were killed by net fisheries (trammel net; set gillnet; driftnet) (2% of the population abundance) which exceeds both ASCOBANS thresholds. In some parts of the fleet catches have declined likely though reduced fishing effort and use of acoustic deterrents. Set net fisheries, have caught common dolphins (Delphinus delphis) and striped dolphins (Stenella coeruleoalba) an IUCN listed Threatened species. No anthropogenic mortality (or bycatch) limits have been defined for the common dolphin in the Northeast Atlantic. Based on the number of strandings, it was estimated that up to 11,000 common dolphins were killed in the Bay of Biscay by fishing, the highest ever recorded level: this level of mortality would likely contribute to a decline in the common dolphin population there. France is carrying out research and developing plans (including acoustic repellents, avoidance tactics, better data collection and quantified mortality reduction targets) to reduce dolphin mortality from bycatch. Some measures are already required under EU legislation. In May 2020, ICES concluded that proposed measures by NGOs for the common dolphin in the Bay of Biscay are appropriate to reduce the bycatch. However, several spatio-temporal and technical amendments are recommended. ICES advises, for the common dolphin in the Bay of Biscay, a combination of temporal closures of all metiers of concern and application of pingers on pair trawlers to mitigate bycatch outside of the period of closure. Application of ICES advice and the appropriate proposed measures is yet to be displayed.

A number of areas are closed to fishing at certain times of the year, e.g. the Trevose box, an areas of sea around 11,400 square miles extending from Trevose head in Cornwall to the Gower peninsular in South Wales from January to March. This is the spawning period for a number of demersal stocks, while it is primarily intended to reduce catches of spawning cod, other stocks are likely to benefit. Anglerfish are ambush predators who feed opportunistically on passing prey, which is attracted using a fleshy lure on the illicium. The diet is dominated by fish and, to a lesser extent, cephalopods. Small gadoids have a relatively high importance in their diet. There are no reports of predators that specifically target anglerfish in European waters. Indirect predation by seals of netted fish is common though and seals may prey directly on anglerfish as well. There have been reports of anglerfish being predated upon by sperm whales, and juvenile fish by large cod.

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.

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.