Fin-nipping breakthrough?
A fledgling trial that's looking at ways to prevent juvenile salmon from nipping each other’s fins in hatcheries is showing promising results.
David Roadknight and his team at Loch Duart’s hatchery in Sutherland have experimented with “putting some environmental enrichment” into hatchery tanks to help to reduce “the boredom factor” that might be part of the cause of the fin-nipping behaviour.
Measures include putting strips of tarpaulin in the tanks to give the fish a place to hide from “bully fish” and introducing strings of brightly coloured plastic balls as “points of interest and items for the salmon to play with and around…breaking the pattern of endless aimless circles.”
According to Loch Duart: “It is already clear that it changes the swim patterns in tanks and dorsal fin quality already seems to be improved.” And the project that has now attracted the interest of researchers at Stirling’s Institute of Aquaculture (IoA).
The IoA’s Professor Jimmy Turnbull explained: “This is obviously a very small study and you cannot extrapolate too far from it – but the fish in the tanks with enrichment apparently have better fins and this is very promising”.
