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Undulate ray

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Undulate ray


A beautiful ray, a member of the skate family the undulate ray has striking undulating patterns of darker lines and spots across a pale grey to sand yellow background.

Sustainability Overview

This striking species is protected and listed as Endangered by IUCN. It is very unlikely that you will find one offered for sale in Cornwall but if you ever do or if you catch one please report it to Cornwall Wildlife Trust. 
Catches of undulate rays are limited by quota and landings were prohibited between 2007 and 2015. Little is know about stocks but the data we do have suggest that stocks appear to have rebuilt following this measure and in localised areas they are reported to be doing well. As they are rare in Cornish waters they are not recommended by Cornwall Good Seafood Guide.
In 2021 a total of 3.8 tonnes of undulate ray were landed to Cornish ports with a value of £4.8k (MMO data).
Updated July 2023.

Sustainability ratings for this species

All Applicable Methods

Cornish vessels landing to Cornish ports

Avoid eating this species, regardless of method used to catch it.

Learn more

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.


The undulate ray is a medium sized skate that grows to a maximum length of 100cm and weight of 10kg. The species lives for up to 20 years and is not sexually mature until it is 9 years old and 75cm in length. Eggs are laid from March to September. They live on the seabed and feed on a range of invertebrates, crustaceans, molluscs worms and fish.

Stock Info

This species has a patchy distribution and is only found in the English Channel and is rare in Cornish waters. Knowledge of its stocks are not good enough to predict the population. Until recently identification to species level was not carried out when recording landings of skate species. In 2009 the EU designated the Undulate Ray as a Prohibited Species for commercial fishing vessels in ICES areas 6, 7, 8, 9 and 10 but the fishery is now open to a small amount of landings in this area. The level of landings are small to Cornish ports. Catches must be reported separately under a specific code alongside important information about the catch.The latest ICES report 2018 shows that stocks have increased but are now slightly decreasing. 



The EU designated the undulate ray as a Prohibited Species for commercial fishing vessels in areas XI, VII, VIII, IX and X. This means fishers are prohibited from targeting, retaining, transhipping and landing the species. The European Commission granted the UK and other member states specific quotas for undulate ray in 2015. In March 2019, the UK introduced a limit of 70kg of bycaught undulate ray per vessel, per trip. This also includes a minimum landing size of 78cm, and a maximum landing size of 97cm to protect highly reproductive individuals. Landings are prohibited during May, June, July and August.


In 2007, Fisheries Science Partnership projects (fishers and scientists working together) were conducted to investigate discard survival rates in trawl fisheries to find out the survival rate for skates and rays that would be discarded with the introduction of a maximum landing length. The projects also aimed to develop species identification onboard and contribute to improved data collection. The Skate and Ray Producers Association has recently been working to improve the lack of species specific data by reporting their catches by species into a central database. This follows previous collaborative work with the Shark Trust and Seafish Industry Authority, to produce an identification guide to help distinguish different species. 

Capture Info

Skates and rays are often caught in beam trawls, demersal trawls and gill nets. Undulate rays must be returned immediately to the sea when caught. 
These fishing methods all have issues with by-catch of non target species and impacts on the wider marine environment.


ICES Advice 2022
IUCN red list Undulate Ray
MMO landings data
Shark trust factsheets Shark Trust; 2009. An Illustrated Compendium of Sharks, Skates, Rays and Chimaera. Chapter 1: The British Isles. Part 1: Skates and Rays.
Seafish responsible sourcing guides 
ICES Advice Rays and Skates in the Celtic sea ecoregion 2013
Enever, R., Revill, A., Grant, A. (2009) The survival of skates (Rajidae) caught by demersal trawlers fishing in UK waters. Fisheries Research 97 (1-2) 72-76
Ref  -Cheung, W.W.L., T.J. Pitcher and D. Pauly, 2005. A fuzzy logic expert system to estimate intrinsic extinction vulnerabilities of marine fishes to fishing. Biol. Conserv. 124:97-111
ICES advice October 2014 Undulate ray in Celtic sea and West of Scotland.

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