Megrim

Lepidorhombus whiffiagonis

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — West, Southwest Ireland, Bay of Biscay
Stock detail — VIIb-k and VIIIa,b,d
Picture of Megrim

Sustainability rating four info

Sustainability overview

The stock is healthy although fishing pressue is too high. Avoid eating immature fish (less than 25cm) and during their spawning season (January to April). Increase the sustainability of the fish you eat by only choosing fish trawled with nets using measures to increase their selectivity.

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

West, Southwest Ireland, Bay of Biscay

Stock information

Two species of megrim are landed to west of Britain and in the Bay of Biscay, megrim (Lepidorhombus whiffiagonis) and four-spot megrim (L.boscii). The former is more common and the only one assessed. This is the second time since 2006 that ICES has provided advice based on an analytical assessment of this stock. The spawning-stock biomass (SSB) for this stock has been above MSY Btrigger since 2008. The fishing mortality (F) has decreased since 2004, although it is still too high and above FMSY. Recruitment (R) has been relatively stable throughout the time-series.

ICES advises that when the MSY approach is applied, catches in 2018 should be no more than 15 720 tonnes. If discard rates (18%) do not change from the average of the last three years (2014-2016), this implies landings of no more than 12 884 tonnes.

Management

There is no management plan for megrim in this area. The ICES advice is for L. whiffiagonis, as the only species assessed. The two megrim species (L.whiffiagonis and L.boscii) are not separated in the landings and a single TAC covers both species. ICES considers that management of the two megrim species under a combined TAC prevents effective control of the singlespecies exploitation rates and could lead to overexploitation of either species. ICES does not presently have catch data for L. boscii in this area and, therefore, does not know how much this species contributes to the overall megrim landings. Data from research surveys indicate a strong predominance of L. whiffiagonis.

Capture Information

Megrim is caught in mixed fisheries, mostly by trawlers. Spanish and French vessels report more than 75% of the total landings. There is a potential damage to the seabed from trawling. Trawling is also associated with discarding of unwanted fish, i.e. undersized and/or non-quota and/or over-quota species.The minimum landing size for megrim in EU waters is 20cm (25cm in Skagerrak/Kattegat). This was reduced from 25cm in 2000. There is believed to be discarding (18%) of megrim over the minimum landing size to meet market requirements. ICES advises that improvements be made to the selectivity of gear to improve the sustainability of the stock and longterm yields from the fishery.

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/meg.27.7b-k8abd.pdf