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A medium sized flat fish that is very closely related to plaice. 

Sustainability Overview

Flounder stocks are unstudied in our area but across Europe their abundance appears to be increasing. There are few management measures for this species but  in Cornwall minimum landing size is 25cm.  This species is rarely landed by Cornish fishermen and rarely commands a good price but it is delicious and under-utilized. 

Sustainability ratings for this species

Beam Trawling

Beam trawls are nets with a steel beam that holds the net open. The belly of the net is made of chains and the upper surface of the net is mesh. Beam trawlers pull two nets along the seabed simultaneously.

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Demersal Trawl

Demersal trawls are large nets that are pulled through the water with the bottom edge of the net touching the seabed. At each edge the net is pulled open by metal ‘trawl doors’. Sometimes referred to as Otter trawling.

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How we rate fish

Cornwall Good Seafood Guide rates fish on sustainability using a scale of 1 to 5.

1, 2 and 3 are recommended, Fish to avoid are rated 5.

We use the system devised by the Marine Conservation Society (MCS) so our scores are comparable with the scores produced by MCS for the UK and fisheries from all around the world. For more information on scoring click here.


Flounders are flat fish that prefer estuaries. It is a species with a more northern distribution and it at the lower edges of its distribution in Cornwall. They spend most of their time in estuaries but can also be found at sea at depths of up to 50 metres. They feed on invertebrates and small fish and live up to 15 years. It spawns between February and June.

Stock Info

This stock is relatively unstudied in Cornish waters. Landings to Cornish ports fluctuate between 2 and 14 tonnes per year.  According to a study carried out by CEFAS flounder is classed as an underutilized species that is tolerant to fishing and are therefore a good species for consumers to try.


There are no management measures in place except a minimum landing size of 25cm in CIFCA district. Catches are not limited as it is a non-quota species. Total landings are up to 12 tonnes per year so it is not a massively important species in Cornwall. 

Capture Info

Flounder are caught as by catch in trawls and gill nets.


Seafish sustainable sourcing guide Flounder 2014
WGNEW 2013
Project Inshore pre assessment database 2014
MMO landings data 

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