Megrim

Lepidorhombus whiffiagonis

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — Northern North Sea and West of Scotland
Stock detail — IVa and VIa
Picture of Megrim

Sustainability rating two info

Sustainability overview

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).

Biology

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 20 cm at 2.5 years old. Males reach first maturity at a lower length and age than females. Megrim can attain a length of about 60 cm, although more usually 35-45 cm, and a maximum age of 14-15 years.

Stock information

Stock Area

Northern North Sea and West of Scotland

Stock information

Fishing mortality for this stock has been declining since the mid-1990s and has been well below FMSY since the mid-2000s. Spawning-stock biomass (SSB) has been increasing since the mid-2000s and is above MSY Btrigger. ICES advises that when the MSY approach is applied, catches in 2018 should be no more than 7800 tonnes (8567 t in 2016 and 2017; 7000t in 2014 and 2015). Discard rates are assumed to have declined, from 30% to an estimate of 15% in 2012.

Management

There is no agreed precautionary management plan for megrim in this area. 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. Management measures for other species have constrained the fishery and reduced effort and fishing mortality on megrim. When there are restictive quotas for anglerfish, area misreporting of megrim catches from subarea VI into subarea IV can be a problem. 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. Since 2014, there has been increasing coverage by the Scottish industry/science observer sampling scheme in divisions 4.a and 6.a.

Capture Information

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.

Alternatives

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.

Dab
Halibut, Atlantic (Farmed)
Halibut, Pacific
Megrim
Plaice
Sole, Dover sole, Common sole
Turbot (Farmed)

References

ICES Advice 2017 http://ices.dk/sites/pub/Publication%20Reports/Advice/2017/2017/lez.27.4a6a.pdf