Common whelk

Jersey common whelk (Buccinum undatum) stocks are in a poor state and fishing pressure is above sustainable levels. According to the most recent stock assessment, carried out by Ifremer (that covers stock in both Jersey and French waters) inclusive of fisheries data up to 2021, the spawning biomass (B) is above the alert threshold (0.5 Bref/Btrigger) at ~0.7, but considerably below the upper B threshold/Maximum Sustainable Yield (Bmsy) of 1. This indicates that the stock is overfished and close to Btrigger, the threshold which fishing mortality must be reduced to restore the stock. Fishing pressure (F) was above the Maximum Sustainable Yield (Fmsy) at ~1.2, also indicating that the stock is subject to overfishing.The Government of Jerseys Fisheries and Marine Resources Department have identified an overall declining trend in the Jersey whelk stock with no significant improvement on catches over the last 10 years. The government conduct annual whelk trials to monitor Catch Per Unit Effort (CPUE). In 2021, CPUE for large whelks (>50 mm) was 1 kg/pot, a 0.1 kg decrease on the CPUE recorded in 2020, and significantly below the 1998-2002 average of 2.64 kg. CPUE of small whelks (<50 mm) has displayed a continuous increase since 2016. In 2021, CPUE for small whelks increased to 0.5 kg/pot, the highest result since 2007 (0.456 kg/pot). This shows some positive signs for future recruitment. Landings Per Unit Effort (LPUE) has steeply declined since 2016, which peaked in 2010 (284 kg/100 pots) and recorded at the lowest LPUE in 2020 (126 kg/100 pots), a change of -42%.In 2021, Jerseys total catch was 182.095 tonnes, a marginal catch increase from 2020 (179.440 tonnes) but a considerable drop from 735.443 tonnes in 2019, and a 60% decrease on the average annual catch over the last 5 years (2017-2021). Landings Per Unit Effort (LPUE) have steeply declined since 2016, peaking in 2010 (284 kg/100 pots) and at lowest recorded levels in 2020 (126 kg/100 pots), a change of -42%.The Marine Stewardship Council (MSC) certified French whelk fishery is significantly larger (annual volume ~5,000-6,000 tonnes) than the Jersey whelk fishery. The French whelk fishery takes place in both Jersey and French waters but catch reports are unable to identify the proportion of catch taken from Jersey and French waters.

There are management measures in place, which are partly effective in managing the stock.A Minimum Conservation Reference Size (MCRS) of 50mm is in place for whelk fished within Jerseys Territorial Sea but provides limited potential for protecting spawning stocks, as whelks generally reach sexual maturity >62.7mm in English inshore regions and reportedly between 56-63mm in Jersey and 49-52mm in Normandy - France. Consequently, it is highly likely whelks are being caught before they have had chance to reproduce. Jersey is gathering more data to better determine whelk size at sexual maturity (SOM - the size at which 50% of the population is sexually mature) and seasonality to inform future management decisions. Whelk SOM is known to vary significantly in different areas around the UK, with temperature and depth being key factors.Jersey's shared fisheries access scheme with France, permits both French and Jersey fishers to access the whelk fishery in Jersey waters. All French vessels accessing Jersey waters (3-12 nm) have Marine Stewardship Council accreditation in the whelk fishery, which covers catch in both French and Jersey waters. Jersey and France work together on data collection and have a mollusc working group to inform management for both authorities. All commercial fishing vessels must have a permit to fish whelks:Vessels over 12 meters are not permitted.Vessels must keep logbook: collecting data on fishing effort (number of whelk pots shot during the day), areas fished, and total catch per fishing day.Fishing effort is restricted to 900 whelk pots per vessel, which must be tagged.Total number of whelk pots within Jerseys Territorial Sea must not exceed 9,000 (Global pot cap).Fishers must use graders with a minimum 22mm bar spacing, to protect small (<50mm) whelks.Vessels may only set whelk pots in the inshore area (0-3nm) on Jerseys East coast between 1st November and 28th February each year. Whelk pots must not be left within this zone outside of this period.Where whelks are caught as by-catch using any type of fishing gear other than whelk pots, the maximum live weight of whelks that may be retained on-board, carried on-board or landed in any day is 5kg.There are a number of management measures in place for this fishery and sampling data within Jersey waters has revealed a stable sampling return, in recent years. An annual study of whelk Catch Per Unit Effort (CPUE) is conducted each February by the Jersey Government. Several strings of baited whelk pots are deployed for 24 hours to the North, East and South of Jersey. When the pots are hauled the whelks are graded and weighed. Results are used to measure changes in whelk density at key locations. These whelk trials have been conducted since 1996 and contribute to important population monitoring. Jersey is a member of the Whelk Working Group (WWG), formed in 2019, to facilitate the exchange of information between Fisheries and Conservation Authorities (IFCAS), government agencies, fisheries authorities, academics, researchers and others interested in whelk fisheries. WWG aims to help improve and develop the understanding of whelk and look at the advantages of joint working to develop appropriate management. WWG is comprised of representatives from organisations engaged in the provision of evidence, advice and management of the whelk fishery on a national level. The WWG offers encouraging opportunities for future growth of effective whelk management by working together to improve communication, collaboration and consistency.In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them.In the UK, it is too early to tell how effective management is, as the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs). FMPs are currently in development, but the scope of them remains unclear. They have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. MCS is keen to see publicly available FMPs for all commercially exploited stocks, especially where stocks are depleted, that include:Targets for fishing pressure and biomass, and additional management when those targets are not being met, based on the best available 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

Common whelks are caught in pots or creels, these are baited traps designed to attract and trap mobile species. Pots or creels have minimal impact on the surrounding environment but may result in damage to rocky reef habitat.Common whelk, or waved whelk, are a marine benthic species, found on muddy sand, gravel or sometimes rock from the low water to depths of greater than 1000m. Whelks are active predators feeding on worms or bivalve molluscs.Jerseys whelks are mostly caught using traditional larger tub pots by Jersey boats, French fishers use smaller concrete or stell-based baskets, set in depths of 10-30m. They are baited with fish and shellfish (soft shelled brown crab is prohibited) and set along one string. A drum or table type grader is used to filter catch, minimising bycatch whilst retaining large whelks. Bycatch typically consists of starfish and various crab species (particularly Spider crab) which is normally caught alive, and undamaged, and can be returned to the sea immediately.Bycatch species can be caught during fishing or if pots are lost (ghost fishing). Although, non-target species can usually escape creels after days or weeks especially if the pots include escape gaps for smaller animals. Invertebrates are understood to have high survival rates when discarded from pots or creels. There is potential for entanglement of endangered, threatened or protected (ETP) species from the ropes attached to the pots. The main species at risk in and around the UK are minke and humpback whales, basking sharks and leatherback turtles.Habitat impacts from potting are low but can occur during deployment, soak time or hauling of the pot, impacting the benthic habitat and associated species through contact with the pot or end weight, or by scouring from ropes. While some damage does occur, it is unlikely to be significant unless potting intensity is high (defined as approximately 30 pots per 500 square metres). Most damage occurs where traps are set in rocky habitats that are home to slow growing anchored species including soft corals, sponges and sea mats.