Razor clam
Ensis spp.
What to check for
Location
Scotland
Technical location
Atlantic, Northeast, North Sea (Central), North Sea (North), West of Scotland
Caught by
Hand-gathering (diving), Hand-gathering (shore)
Rating summary
This stock is data limited. There is concern for the biomass and fishing pressure due to lack of data. There are few appropriate management measures in place for shore based gathering of razor clam fisheries in Scotland. No stock information or management measures have been implemented in Scotland, despite a long standing electrofishing trial designed for this purpose. There are also concerns that electrofished clams are sold as purely hand gathered when they have been stunned using electrofishing gear and then dive gathered. More data and transparency on the market is needed to improve management. Shore based hand gathering of razor clams is a low impact fishing method as there is no bycatch and it is unlikely to cause habitat damage.Rating last updated in December 2022.
Technical consultation summary
This stock is data limited. There is concern for the biomass and fishing pressure due to lack of data. There are few appropriate management measures in place for shore based gathering of razor clam fisheries in Scotland. No stock information or management measures have been implemented in Scotland, despite a long standing electrofishing trial designed for this purpose. There are also concerns that electrofished clams are sold as purely hand gathered when they have been stunned using electrofishing gear and then dive gathered. More data and transparency on the market is needed to improve management. Shore based hand gathering of razor clams is a low impact fishing method as there is no bycatch and it is unlikely to cause habitat damage.
How we worked out this Rating
There is very little information available about razor clams in the UK. There is concern for the population biomass and fishing pressure due to lack of data.The species caught as razor clams (Ensis spp.) in this fishery are data limited due to the lack of information relating to biomass and fishing pressure. Consequently, Route 2 (data limited) scoring has been applied to this rating. Razor clams are assessed as having low vulnerability to fishing pressure (10 out of 100).There is no stock assessment data for razor clams in the UK. Thus, at present, there is no data to guide sustainable fishing pressure or healthy biomass levels. Despite razor clams having low vulnerability to fishing pressure, it could take several years for commercial stocks to recover in an area due to intermittent recruitment and the slow growing nature of these species. Because of the lack of data, there is concern for stock biomass.An electrofishing trial has been underway in Scotland since 2018. Only data for razor clams that are landed in this fishery is recorded. Information about wild populations overall is not collated. Between 2018 and 2022, landings have ranged between 1 and 120 tonnes per month. From Jan 2021 to Jan 2022, the average value of landings was £7,800 per tonne. Landings per unit effort (LPUE), often used as a proxy for abundance, has been recorded throughout the trial. LPUE from 2018-2021 shows reductions in some areas. LPUE data for 2021 onwards has not been published. As there is no assessment of the sustainability of the fishery, there is concern for fishing pressure.
There are few appropriate management measures in place for shore based gathering of razor clam fisheries in Scotland. No stock information or management measures have been implemented in Scotland, despite a long standing electrofishing trial designed for this purpose. There are also concerns that electrofished clams are sold as purely hand gathered when they have been stunned using electrofishing gear and then dive gathered. More data and transparency on the market is needed to improve management.In Scotland there are catch limits for hand-gathering of 30 clams per day, although there is no information available about how this enforced. There is also no information about how the spatial extent, fishing intensity and total landings of hand-gatherers.There is a minimum landing size (MLS) of 100 mm applied to the Ensis species for all European stocks, but this is often lower than the size at which they mature. No stock information has been published despite an electrofishing trial being active for several years (since 2018) and no management measure based on the trial results have been implemented.In Scotland, all other fishing for razor clams is prohibited unless vessels are part of a current electrofishing trial (which relies on divers to collect stunned clams). Therefore, all clams should either be from shore-based hand gathering or vessels licenced for the trial. It is currently difficult for consumers to identify whether dive caught clams are caught using electrofishing in Scotland, making monitoring difficult. However, as hand gathering or diving of razor clams is not commercially viable due to low catch rates, it is unlikely that hand gathered clams will be on the market in any quantity. Further information about all landings reaching markets and clear labelling requirements about fishing methods would be needed to fully understand the razor clam fishery in Scotland.There has also been a very lucrative illegal market for razor clams in Scotland and more widely. It is not clear whether current management approaches are protecting the fishery from illegal activity. Some sellers provide clear information about how vessels are licenced but there are indications that illegal fishers transport catches to Scotland for sale.
Shore based hand gathering of razor clams is a low impact fishing method as there is no bycatch and it is unlikely to cause habitat damage.Hand gathering of razor clams is permitted across Scotland. There is no information about the scale and extent of hand gathering of razor clams in Scotland. It is understood that hand gathering occurs both on the shoreline and below the tide line using snorkels or dive gear.Hand gathering of razor clams is a low impact fishing method as it directly targets individual shellfish so there is no bycatch. Often large quantities of salt are used to force the buried clams to the surface, and the impacts of this on other species around the clam holes are not known. Additionally, large scale removals may alter the density of the sand.If clams are harvested very intensively in any areas there may also be impacts on other species in the food chain. There is no information about razor clam harvest impacts on the wider ecosystem in Scotland, however, in Wales there are concerns that wading birds are affected by the reduction in prey.Evidence suggests that hand diving of razor clams is not commercially viable without the use of electrofishing gear to expose the shells for harvest by divers. Therefore, it is expected that the vast majority of razor clams will be caught using electrofishing in Scotland.
References
BIM, 2019. Shellfish Stocks and Fisheries Review 2019. The Marine Institute and Bord Iascaigh Mhara. Available at: https://oar.marine.ie/bitstream/handle/10793/1591/Shellfish%20Stocks%20and%20Fisheries%20Review%202019_FINAL.pdf?sequence=1&isAllowed=y [Accessed on 23.11.22].Fox, C. (2017) To Develop the Methodology to Undertake Stock Assessments on Razor Fish Using Combinations of Video Monitoring and Electrofishing Gear. Scottish Marine and Freshwater Science Vol 8 No 6, 92pp. DOI: 10.7489/1908-1.Fraser, S., Shelmerdine, R.L., and Mouat, B. (2018). Razor clam biology, ecology, stock assessment, and exploitation: a review of Ensis spp. in Wales. NAFC Marine Centre report for the Welsh Government. Contract number C243/2012/2013. pp 52. Available at: https://pure.uhi.ac.uk/en/publications/razor-clam-biology-ecology-stock-assessment-and-exploitation-a-re [Accessed on 23.11.22]. Loch Fyne, 2022. PRODUCE, RAZOR CLAMS. Available at: https://www.lochfyneseafarms.co.uk/produce/razor-clam/ [Accessed on 8.12.22].National Assembly for Wales. 2017. P-05-778 Protect the Razor Clams on Llanfairfechan Beach. Available at: http://senedd.assembly.wales/mgIssueHistoryHome.aspx?IId=19792. [Accessed 03.11.22].Palomares, M.L.D. and Pauly, D. Editors. 2022. SeaLifeBase: Ensis siliqua, Sword razor shell. Available at https://www.sealifebase.se/summary/Ensis-siliqua.html [Accessed on 23.11.2022].Scottish Field, 2020. BURIED TREASURE. Available at: https://www.pressreader.com/uk/scottish-field/20200303/281539407944122 [Accessed on 2.11.22].Scottish Government, 2021. Electrofishing for razor clams trial: update report - 1 February 2020 to 31 January 2021. Available at: https://www.gov.scot/publications/update-electrofishing-razor-clams-trial-1-february-2020-31-january-2021/pages/3/ [Accessed on 23.11.22].Scottish Seafood, 2022. Razor Clam. Available at: https://scottish-seafood.com/sg/razor-clam/ [Accessed on 3.11.22].Y Gwasanaeth Ymchwil. Research Service. 2017. Petition: Protect the Razor Clams on Llanfairfechan Beach. Petition number P-05-0778. Petitions Committee 3 October 2017. Available at: http://www.senedd.assembly.wales/documents/s66500/Research%20Brief.pdf
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