Red mullet

The striped red mullet population (or stock) in this region is buoyant in size but fishing pressure is just above sustainable levels.The stock size indicator shows the population to largely fluctuate throughout the time series but has remained above the maximum sustainable yield trigger point (MSY Itrigger 117.38 kg/km2 - below this level, F should be reduced to allow the stock to increase) since 2017. In 2022, the stock size increased to 306.13 kg/km2, from 238.12 kg/km2 the previous year (2021).Fishing pressure (F) on the stock has remained just above Maximum Sustainable Yield (FMSY proxy 1) since 2019 and been at or around FMSY proxy from the early 2000’s. In 2022, F was 1.072, a slight increase from the year previous (1.048 in 2021) but almost equal to F in 2019 and 2020.ICES advises that when the MSY approach is applied, catches should be no more than 1,985 tonnes in each of the years 2024 and 2025. All catches are assumed to be landed.Stock structure remains an issue and a source of uncertainty.

There are some management measures in place, but the striped red mullet population is fished without limit and significantly above advised levels, whilst being caught before having had the chance to reproduce.The EU multiannual plan (MAP) for stocks in the North Sea and adjacent waters applies to bycatches of this stock. It aims to ensure that stocks are exploited sustainably and that the decisions on fishing opportunities are based on the most up-to-date scientific information. UK and Norway have not requested ICES to provide advice based on the EU MAP.Striped red mullet is not subject to Total Allowable Catch (TAC) and quotas. Total catches have been markedly above advised annual catch levels every year catch advice has been provided, since 2012 (except in 2013). Between 2014 and 2019, the average total catch was 573% (ranging 373-975%) of advice. In 2022, total catch again exceeded advice, at 147% of the advised limit.There is no minimum landing size for striped red mullet and there is a market for small fish. Recent catches of this stock mainly consist of fish ages 0 and 1. Striped red mullet start maturing at age 1 but are not fully matured before age 3. The stock status would therefore benefit from improved technical measures, such as sorting grids, increased mesh size, and spatial and temporal closures. These measures could reduce the catches of small fish and contribute to more stable yields.However, a Minimum Conservation Reference Size (MCRS) does apply to striped red mullet fished within some Inshore Fisheries Conservation Authorities (i.e., Southern, Cornwall, and North Western IFCAs: 15 cm), providing some protection to immature fish within English inshore waters. Striped red mullet reaches sexual maturity at an average of 16.1 cm (ranging 15-26 cm).Discards are assumed negligible.In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them.In the UK, the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans). FMPs have the potential to be very important tools for managing UK fisheries. They will set out the policies to secure the long-term sustainability of our fish stocks for current and future generations and can include (data allowing):Targets for fishing pressure and biomass, with effective management to meet them;Timeframes for stock recovery;Use of technologies such as Remote Electronic Monitoring (REM) to support data collection, improve transparency and accountability;Consideration of wider environmental impacts of the fishery.

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.The striped red mullet is a benthic fish found mostly on sandy bottoms. Young fish are distributed in coastal areas, while adults have a more offshore distribution. In 2022, 71% of the total catch was taken by Danish seine (also known as fly shooters), 19.7% by otter trawlers, and a further 9.3% by other fishing gears.Demersal trawls penetrate the seabed, resulting in the abrasion of habitat features. The impact of trawling on the seabed depends on where trawling happens, and on what scale. For example, habitats that are used to natural disturbance through tides and waves are less sensitive to impacts. Areas not used to mobile towed gears are typically more sensitive.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, protected and threatened (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.The main mitigation measures are Marine Protected Areas, some of which are designated for benthic features. If those MPAs were found to be subjected to bottom trawling, MCS would consider it a default red rating unless there is evidence (e.g., environmental impact assessment) indicating the activity does not damage the integrity of the site.UK regulations to reduce the impacts of fishing on marine habitats and wider species are under development, in the meantime most EU regulation have been adopted. Under EU legislation, bycatch species should be managed within scientifically defined or, where data isn’t available, suitability precautionary sustainable exploration limits. If stocks fall below a certain threshold, measures can be brought in such as gear limitations (e.g., mesh size or depth of use), time and/or areas closures, and Minimum Conservation Reference Sizes (MCRS).

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