Scallop, King, scallops
Capture method — Dredge
Capture area — North East Atlantic (FAO 27)
Stock area — England
Stock detail —
Eastern Channel Inshore (0-6nm)
FIP Stage 2
A Fishery Improvement Project has begun in the Channel fishery which is predicted to enhance monitoring and management in the fishery. Currently there are a lack of data on the population size of Channel scallops and stocks are ill-defined. There are some negative population trends: landings, effort and productivity have all decreased since 2012. Management measures include effort restrictions, limited licencing and technical measures (minimum mesh sizes). The inshore fishery is enforced well, using Vessel Monitoring Systems (VMS) and patrols. There are a wide variety of bycatch species caught and more data are required to understand both the direct and indirect impact of the fishery on Endangered, Threatened and Protected species such as skates, rays and sharks. There is scientific consensus that dredges present a greater risk to seabeds habitats and species opposed to other bottom trawl gears. In the inshore waters, there has been significant protection by the IFCAs to reduce the risk of fishing in vulnerable habitats through spatial management.
Of concern is the use of bottom towed fishing gear in Marine Protected Areas (MPAs), especially sites to protect seabed features or where an appropriate impact or risk assessment has not been undertaken to demonstrate that the activity has no significant effect to the site.
King scallops are bivalve molluscs found in a range of depths from shallow waters in sea lochs to over 100m. They inhabit sandy-gravel and gravel seabeds. They have 2 shells or valves, the upper being flat, and the under or right valve, cup shaped. They are hermaphrodites (i.e. both male and female) and become fully mature at about 3 years old (80 to 90mm in length). Spawning occurs in the warmer months, from April to September. The species can grow to more than 20cm in length and live for more than 20 years, although average sizes are in the range of 10-16cm.
Criterion score: 0.5 info
The scallop stock in ICES Area 7 are poorly defined which the ICES Scallop Assessment Working Group is currently trying to improve. There are no reference points for the stock. Landings, effort and productivity have all decreased since 2012. MLS is above the size at maturity, and therefore, is unlikely to impair recruitment.
To determine the stock status for scallops, researchers need to define the level where the stock is sustainable and/or where the stock population is at risk. These levels are called reference points. In the absence of reference points, it is difficult to determine how healthy a population is.
The ICES Scallop working group have attributed recent declines in scallop recruitment, particularly in the Eastern English Channel, to environmental fluctuations, particularly regarding changes in average sea-surface temperature in early summer.
There is no conclusion regarding the stock status because there has been little interpretation of the data (e.g. no reference points).
Criterion score: 0.5 info
Criterion score: 0.5 info
Scallops represent the majority of landings from dredges, followed by monkfish, sole, plaice, turbot, brill, cuttlefish, brown crab. The main discard species include crabs, dogfish, Nursehound, Dragonet, Green sea urchin, Starry ray, Smelt, Ocean quahog and starfish. Some sensitive species are caught, including starry ray, common skate (Dipturus batis), thornback rays, porbeagle and nursehounds.
Dredges can cause considerable impact on benthic habitats and is a significantly more damaging method of fishing compared to dive-caught methods. This can lead to damage to important habitats and reduced biodiversity depending on how much mortality is caused by the fishing method and the recovery rate of the biota effected. The impact can be highly site specific. Scallop dredging presents a greater impact to the biota: hydraulic dredges can remove 41% of biota and penetrate the seabed by on average 16.1 cm. The impact of dredging on the seabed vary with different seabed types and how exposed the seabed is to natural disturbance i.e. wave action.
Typically, less exposed seabed areas such as inshore waters and vulnerable habitats are more vulnerable to the effects of dredging. Destroying maerl beds substantially reduces biodiversity, seabed stability, local nursery areas and therefore commercial fisheries. Mixed sand and mud habitats generally have diverse benthic communities with a high biomass. Conversely, seabeds and ecosystems naturally adapted to disturbance by currents and storms e.g. in soft mud / sand sediments are less likely to incur long-term damage. Soft sediments are generally much less sensitive to disturbance, depending on their sediment structure, morphology and presence of vulnerable features.
The most common habitats for scallop dredging in the area is on sand, gravel or pebble/ cobbles. However, there are vulnerable marine ecosystems (VME)s within the area including reefs, seagrass beds and horse mussel beds. There is a partial ‘strategy’ through EU, UK and local management regimes to protect habitats. European Marine Sites (SACs & SPAs) are designated throughout the English Channel.
English inshore and offshore marine habitats are relatively well-studied to understand where OSPAR priority habitats (VMEs) are present, and where fishing vessels coincide (vessels over 12m in length are monitored using VMS, and smaller vessels can be monitored e.g. by using surveillance data.
At a local level, the local IFCAs conduct surveys to determine and designate vulnerable features e.g. restrictions on dredging in the IFCA areas and a ban on shellfish dredging within the designated European Marine Site at Lyme Bay.
Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.Abalone
Clam, Manila (Farmed)
Crab, brown or edible
Crawfish, Red Swamp
Lobster, Norway, Langoustine, Dublin Bay prawn or scampi
Mussel, mussels (Farmed)
Oyster, Native, oysters (Caught at sea)
Oyster, Native, oysters (Farmed)
Oyster, Pacific, oysters
Prawn, King (whiteleg), prawns
Prawn, Northern, prawns
Prawn, Tiger prawns (Farmed)
Scallop, King, scallops
Scallop, Queen, scallops
Squid, Japanese flying
ReferencesSouthall, T. 2016. MSC Pre-Assessment for English & Western Channel Scallop fishery (Scallop Dredge). Prepared for Project UK Fisheries Improvements. Edinburgh, UK.
Kent and Essex IFCA. 2017. Dredging: Scallops. Available at: http://www.kentandessex-ifca.gov.uk/im-interested-in/fishing-commercially/dredging/scallops/
Sussex IFCA. 2017. Scallop closed season : SEA FISHERIES REGULATION ACT 1966. Available at: http://www.sussex-ifca.gov.uk/scallop-closed-season
Sussex IFCA. 2011. Inshore Fisheries and Conservation Authority Species Guide. Available at: https://secure.toolkitfiles.co.uk/clients/34087/sitedata/files/SUSSEX-IFCA-Marine-Species-Guide.pdf
Southern IFCA. 2017. Byelaws. Available at: http://www.southern-ifca.gov.uk/byelaws
Hiddink, J.G., Jennings, S., Sciberras, M., Szostek, C.L., Hughes, K.M., Ellis, N., Rijnsdorp, A.D., McConnaughey, R.A., Mazor, T., Hilborn, R., Collie, J.S., Pitcher, C.R., Amoroso, R.O., Parma, A.M., Suuronen, P., Kaiser, M.J., 2017. Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance. Proc. Natl. Acad. Sci. 114, 8301-8306. doi:10.1073/pnas.1618858114
Howarth, L. M. & Stewart, B. D. 2014. The dredge fishery for scallops in the United Kingdom (UK): effects on marine ecosystems and proposals for future management. Report to the Sustainable Inshore Fisheries Trust. Marine Ecosystem Management Report no. 5, University of York, 54 pp
Bangor University. 2017. Fisheries and Conservation Science Group: Scallop Fisheries: Fishery. Available at: http://fisheries-conservation.bangor.ac.uk/iom/scallops.php.en#fishery-tab
ICES. 2016. Report of the ICES Scallop Assessment Working Group (WGScallop) 3-7 October 2016 Aberdeen. Available at: http://ices.dk/sites/pub/Publication%20Reports/Expert%20Group%20Report/acom/2016/WGScallop/01%20WGScallop%202016%20Report.pdf
MMO. 2017. Evidence requirement R046: Impact of external pressures on fisheries in Western Waters (area 7). Available at: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/647357/Impact_of_external_pressures_on_fisheries_in_Western_Waters__area_7_.pdf.
Sciberras, M., Hinz, H., Bennell, J., Jenkins, S., Hawkins, S., Kaiser, M., 2013. Benthic community response to a scallop dredging closure within a dynamic seabed habitat. Mar. Ecol. Prog. Ser. 480, 83-98. doi:10.3354/meps10198
Seafish. 2017. Seafish Economic Analysis: UK king scallop dredging sector 2008-2016. Edinburgh, UK. Available at: http://seafish.org/media/Publications/Scallop_report_FINAL.pdf