Publication Abstract

Stock identity in spurdog (Squalus acanthias L.) around the British Isles

M.R. Vince

In April 1966 a total of 1411 tagged spurdog (Squalus acanthias L.) were released in the Celtic Sea. Recaptured fish continued to be reported from waters all around the British Isles for 20 years. Returns were analysed by sex for seasonality, geographical distribution, recapturing nation, and length at release. Some returns provided data on growth of spurdog. Although some differences were found in the recapture patterns between sexes, the most significant result was the decrease through time in the proportion of returns from the vicinity of release, compared with the corresponding increase in returns from the west of Scotland and the North Sea.

It is suggested that the pattern of long-term recaptures is evidence that juvenile and maturing spurdog might move throughout the whole geographical range of the population inhabiting the shelf water of northwest Europe, and that the seasonal migrations of mature fish do not provide a basis on which to separate stock units for management purposes.

Reference:

M.R. Vince, 1991. Stock identity in spurdog (Squalus acanthias L.) around the British Isles. Fisheries Research, 12: 341-354.