Scallop, Queen, scallops

Aequipecten opercularis

Method of production — Caught at sea
Capture method — Dredge
Capture area — North East Atlantic (FAO 27)
Stock area — Isle of Man
Stock detail

Non-territorial waters (outside 12nm)


Certification

FIP Stage 4 (https://www.fishsource.org/fishery_page/4229)


Picture of Scallop, Queen, scallops

Sustainability rating five info

Sustainability overview

Queen scallops are distributed throughout European waters from Norway to the Mediterranean. A valuable fishery for queen scallops has existed around the UK since the late 1960s. The most valuable fishery for queen scallops in the North-east Atlantic occurs in the Irish Sea and particularly around the Isle of Man, although the species is fished off western Scotland, north Wales and in the North Sea. Very little is known about the state of queen scallop stocks in the UK. The stock is at unsustainable and very low levels. A Pan-Irish Management Agreement is required to ensure that non-territorial stocks are managed sufficiently and do not reduce the stocks in territorial waters.

Queen scallops are caught using otter trawls or dredges. Otter trawls are less damaging to the seabed than dredges, and bycatch is generally lower because there is generally less disruption and interaction with the seabed.

Biology

Queenies are a fast growing species with a maximum lifespan that rarely exceeds five years. Queen scallops are simultaneous hermaphrodites (i.e. an individual has both male and female reproductive organs) and become sexually mature at 1-2 years at approximately 40mm shell height. Although smaller than King scallops they can grow up to about 90mm. Queen scallops are broadcast spawners (i.e. they release eggs and sperms into the sea) and can spawn in both spring and summer. When one individual spawns, pheromones contained in the eggs and sperms released into the water column, signal to neighbouring scallops to release their own eggs and sperms ensuring synchronous spawning. Thus, in order for spawning (and subsequently recruitment) to successfully occur Queen scallops need to be present at relatively high densities. In low density populations there is a risk that the spawning stock may not be present at high enough densities to successfully reproduce (i.e. there are too few individuals around to come into contact for fertilisation), a phenomenon known as the Allee effect. They are usually found at depths down to about 100m on sand or gravel. It feeds on plankton and other organic material by filter feeding. They reach market size of 55mm (minimum landing size in Isle of Man; 40mm for rest of the Irish Sea) within 2-3 years depending on the available micro-algae feed from the water column.

Stock information

Criterion score: 1 info

Stock Area

Isle of Man

Stock information

The most valuable fishery for queen scallops in the North-east Atlantic occurs in the Irish Sea and particularly around the Isle of Man, although the species is fished off western Scotland, north Wales and in the North Sea. Very little is known about the state of queen scallop stocks in the UK, apart from around the Isle of Man where regular surveys are conducted and the trawl fishery was certified as sustainable by the Marine Stewardship Council (MSC) in 2011.The stock is at unsustainable and very low levels. Scientists recommend a reduction in TAC and a precautionary approach which has subsequently been reduced to 992t. The inshore fishery is well-managed with a suite of management measures. However, this has not been sufficient to improve the stock status.

Management includes an annual TAC of a weekly catch limit of 4200 kg (Weeks 1-10) and 2800 kg (Weeks 11 onwards), weekly individual vessel quotas, minimum landing size of 55 mm, a season closure, trawling and dredging seasonal ban, a series of closed areas and temporal fishing restrictions.

A Pan-Irish Management Agreement is required to ensure that non-territorial stocks are managed sufficiently and do not reduce the stocks in territorial waters.

Monitoring occurs through Daily Catch Returns and VMS. Queen scallops are usually caught with otter trawls in the Isle of Man because they are keen swimmers and are easily caught in nets. Otter trawls are less damaging to the seabed than dredges, and bycatch is generally lower. This, coupled with management measures such as MPAs, area closures, and curfews to avoid catching brown crabs (which are more mobile overnight), means that there is a reduced risk to the ecosystem compared to dredging.

Management

Criterion score: 0.75 info

Outside of territorial waters, the queen scallop receives minimal management: a mandatory EU minimum landing size of 40 mm, some control of fishing effort for vessels over 15 metres in length. There are no entry restrictions into the fishery, with no EU Total Allowable Catch (TAC), no curfews and until very recently no seasonal closures.

Unfortunately, fishing effort and landings did not decline when recruitment and landings began to decrease which created significant overfishing in both inside and outside the Manx territorial sea area. The number of licensed vessels were reduced from 138 for the 2014/15 fishing season to 49 for the 2015/16 fishing season. Territorial sea landings were substantially decreased in 2015 (1240t) but landings from the wider area of the biological stock are still above the long-term average (8033t).

Researchers advise that the Irish Sea queen scallop fishery should be managed as a single biological stock and that collaborative management through a pan-Irish Sea management group are essential. The Manx Government has been encouraging the pan-Irish Sea management plan to implement harvest controls to manage fishing effort outside the IOM Territorial Sea. The pan-Irish Sea working group introduced a voluntary ban on queen scallop fishing during May throughout the Irish Sea and to the west of Scotland. There was a consensus from the Pan-Irish Working Group that the following management measures are required: increased Minimum Landing Size (MLS), voluntary closed season, entry restrictions. To be effective, researchers advise that management must include suitable sites for closed areas for spawning and recruitment.

There are only few measures in place to protect the stock, some of which have only recently been implemented. There is no stock assessment for the biological unit but they are likely in a poor condition. The fishery requires considerable improvement or specific management measures to be implemented.

Capture Information

Criterion score: 0.75 info

Queen scallops are active swimmers and when disturbed by tickler chains on otter trawl, quickly swim upwards and are captured in the fishing net. Otter trawls are used in the summer season when higher temperatures cause this swimming behaviour while skid dredges being used are used in the winter months.

Bycatch and discarding is monitored and managed by the IOM Government and the Manx Fish Producers Organisation. Bycatch is generally considered as low (<10%) in the Manx Queen scallop trawl fishery, but has increased in recent surveys. Bycatch significantly varied between fishing ground and time of year, but generally includes: fish (e.g. dab, cod, whiting, gurnards, monkfish), cephalopods (e.g. squid), elasmobranchs (e.g. smoothounds, blonde ray, thornback ray, spotted ray, cuckoo ray, small-spotted catsharks, nursehounds) and invertebrates (e.g. Dead man’s fingers, oyster, sea squirts, star fish, whelk, sea urchin, crabs). However, many invertebrates are unidentifiable or not retained in the surveys.

Otter trawls catch exhibit higher levels of finfish bycatch but are more environmentally friendly to habitats compared to dredges. ‘Newhaven’ dredge cause less damage per catch compared to the traditional dredges.

Recent surveys have observed general increases in discard rates of undersized queen scallops but discard mortality from otter trawling is nearly a third of that observed in skid dredges. The introduction of the new Landings Obligation regulations require some bycatch (e.g. whiting) to be landed.

Mobile fishing gears cause the greatest levels of disturbance to marine benthic communities, either by direct (removal, burial or crushing), indirect (increase susceptibility to predation) or change biogeochemical properties of the environment. However, otter trawls are comparatively much less destructive than dredges.

Habitats and species of conservation concern (some of which are covered by UK BAP, EU Habitats Directive and OSPAR) have identified around the Isle of Man e.g. maerl beds, modiolus beds, sabellaria spinulosa and edwardsia timida. S. spinulosa (the tube-building polychaete worm) are particularly vulnerable because they are located within areas of high queen scallop densities. There is no statutory protection for S. spinulosa reefs in the UK.

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.

There are few management measures to protect the habitat from fishing methods in the larger biological stock unit.

References

Nall, C. R. 2011. Survivability of target species discards in the Isle of Man Queen Scallop (Aequipecten opercularis) fishery. Available at: http://fisheries-conservation.bangor.ac.uk/iom/documents/CNALL_Thesis_07.10.2011.pdf. Duncan, P. (2011). A survey of bycatch In the Isle of Man queen scallop Aequipecten opercularis trawl fishery for the purpose of fishery certification.

Scottish Government. 2017. Consultation on New Controls in the Queen Scallop Fishery in ICES Divisions VIa and VIIa. Available at: http://www.gov.scot/Publications/2017/08/3763/0

Bloor, I.S.M., Dignan, S.P., Murray, L.G. and Kaiser, M.J. 2015. Bycatch Survey - Isle of Man Queen Scallop Otter Trawl Fishery Summer 2014. Fisheries & Conservation Report No. 67, Bangor University. pp. 14

Bloor, I.S.M., Murray, L.G., Dignan, S.P. and Kaiser, M.J. (2015). The Isle of Man Aequipecten opercularis stock assessment 2015. Fisheries and Conservation Report No. 58, Bangor University. pp. 55.

Bloor, I.S.M. and Kaiser, M.J. (2016). The Isle of Man Aequipecten opercularis stock assessment 2016. Fisheries and Conservation Report No. 66, Bangor University. pp. 1 - 36

Dignan, S.P., Bloor, I.S.M., Murray, L.G. and Kaiser, M.J. (2014). Environmental impacts of demersal otter trawls targeting queen scallops (Aequipecten opercularis) in the Isle of Man territorial sea. Fisheries & Conservation Report No. 35, Bangor University. pp. 25. Boyle K., Kaiser M.J., Thompon S., Murray L.G. and Duncan P.F. 2016. Spatial variation in ?sh and invertebrate bycatches in ascallop trawl ?shery. Journal of Shell?sh Research 35, 7 - 15 Fish and invertebrate by-catch in the crab pot fishery in the Isle of Man, Irish Sea (PDF Download Available). Available from: https://www.researchgate.net/publication/319652379_Fish_and_invertebrate_by-catch_in_the_crab_pot_fishery_in_the_Isle_of_Man_Irish_Sea [accessed Sep 20, 2017].

Bangor University. 2016. Fisheries and Conservation Science Group: Scallop fisheries: Fishery. Accessed on 10.08.2017. Available at: http://fisheries-conservation.bangor.ac.uk/iom/scallops.php.en#fishery-tab

Dignan, S.P., Bloor, I.S.M., Murray, L.G. and Kaiser, M.J. (2014). Environmental impacts of demersal otter trawls targeting queen scallops (Aequipecten opercularis) in the Isle of Man territorial sea. Fisheries & Conservation Report No. 35, Bangor University. pp. 25.

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

Hinz, H., Murray, L.G. Gell, F., Hanley, L., Horton, N., Whiteley, H., Kaiser. M.J. Seabed habitats around the Isle of Man. Fisheries & Conservation report No. 12, Bangor University. pp.29

Hinz, H., Murray, L. Malcolm, F. R. , Kaiser, M. 2012. The environmental impacts of three different queen scallop (Aequipecten opercularis) fishing gears. Marine Environmental Research, 73, 85-95pp.

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. 2016. Fisheries and Conservation Science Group: Scallop fisheries: Closed Area Monitoring. Accessed on 10.08.2017. Available at: http://fisheries-conservation.bangor.ac.uk/iom/scallops.php.en#current_projects-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

Isle of Man Government. 2017. Marine Nature Reserves. Available at: https://www.gov.im/about-the-government/departments/environment-food-and-agriculture/protected-sites/marine-nature-reserves

Island Shellfish. 2017. King and Queen Scallop board appointed. Available at: http://www.isleofmanqueenies.co.uk/king-queen-scallop-board-appointed/

Isle of Man Government. 2017. Isle of Man trials new fisheries data management system. Available at: https://www.gov.im/news/2017/jun/02/isle-of-man-trials-new-fisheries-data-management-system

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