Method of production - Caught at sea
Capture method - Demersal otter trawl
Capture area - North East Atlantic (FAO 27)
Stock area - Celtic Sea and West of Scotland
Stock detail - IVa and VIa
Fish type - White flat fish
The stock is assessed as healthy and is being harvested sustainably. Avoid eating immature fish (less than 25cm) and during their spawning season (January to April).
A common flatfish found in shelf seas throughout the northeast Atlantic. Megrim spawns in spring in deep water off Iceland, and between January and April along the edge of the continental shelf to the southwest and west of the British Isles. It is found at depths ranging from 50-800 m, but with the highest abundance around 100-300 m. For both sexes combined, 50% of individuals mature at about 20cm at 2.5 years old. Males reach first maturity at a lower length and age than females. Megrim can attain a length of about 60cm, although more usually 35-45cm, and a maximum age of 14-15 years.
Celtic Sea and West of Scotland
The stock in this area is assessed as having full reproductive capacity and harvested sustainably. Biomass has consistently been above BMSY trigger and has increased steadily since 2005. Fishing pressure has been declining since the late 1990s. Discard rates were estimated at around 11% in 2014. ICES advises that catches should be no more than 8567 t in 2016 and 2017 (7000t in 2014 and 2015). If discard rates do not change this implies landings of no more than 7539t (5950 t in 2014 and 2015;4700t in 2013 and 2014).
No specific management objectives are known to ICES for this stock. Megrim is a bycatch species in the mixed bottom trawl fisheries in this area which is subject to effort managment under the EU cod management plan. Because of restictive quotas for anglerfish area misreporting of megrim catches from subarea VI into subarea IV is prevalent. However this situation is reported to have reversed in response to more restrictive quotas introduced into IV. The extent of the problem is unknown and ICES recommends that it be investigated.
Megrim are predominantly caught using otter trawls as part of a targeted fishery for monkfish or anglerfish, and as bycatch in fisheries for demersal species such as cod and haddock. Male megrim grow to a smaller maximum size than females, and as a consequence the majority of males in the catch are discarded and the bulk of fish landed is comprised of females. The minimum landing size for megrim in EU waters is 20cm (25cm in Skagerrak/Kattegat). Increased mesh sizes brought in to protect cod are expected to also benefit the megrim population by reducing the bycatch of juveniles.
ICES Advice 2015, Book 5 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2015/2015/meg-4a6a.pdf
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