Preliminary observations on the life history and movements of skates (Rajidae) around the Island of Jersey, western English Channel

The most frequently caught skate species around Jersey include blonde ray Raja brachyura, undulate ray Raja undulata, small-eyed ray Raja microocellata and thorn back ray Raja clavata. Between September 2006 and December 2008, a total of 814 individuals were tagged and released, of which 64% were small-eyed ray, 22.6% blonde ray and 12.4% undulate ray. The size distribution, sex-ratio and maturity of these samples are summarized. There were 138 reported recaptures (return rate = 17.1%), with most fish recaptured from the study area. Indeed, many of the tagged skates were recaptured within the same release area or within 20 km, indicating high site fidelity, with the longest distance travelled only 61 km. Thirteen fish were recaptured on multiple (2-4) occasions. To date the longest time at liberty has been 754 days. These results are discussed in relation to our current knowledge of the stock structure and exploitation of skates in the western English Channel.