Is tagged spurdog a record breaker?
Article first published in Fishing News, 22 October 1999
A tagged male spurdog which was captured west of Stanton Bank in
late September 1999 was found to have been at large for almost 35
years when it was examined by scientists from Aberdeen's Marine
Laboratory - possibly a world record for a tagged fish.
When the records were checked it was discovered that the fish
had been tagged and released on 30 October 1964 by scientists from
the MAFF Laboratory, Lowestoft, working 10 miles north of Rona
aboard the research vessel Ernest Holt.
The fish had grown from 66 cm to 78 cm in the 34 years and 11
months leading up to its capture by the fishing boat ASTRA (BF
524) - an average growth rate of one third of a centimetre per
year.
This is not the first time that tagging experiments have shown
that dogfish grow extremely slowly and live to a ripe old age. A
male that was recaptured in 1997 - 34 years and 9 months after it
had been tagged - had grown by only 10 cm.
Because spurdogs grow so slowly and give birth to only a few
pups they are extremely vulnerable to overfishing.
Although the fish landed by the ASTRA was recaptured
fairly close to where it had been released nothing is known about
its movements during its period of freedom.