A new project is trying to find out whether personality makes Ballan wrasse more adept at picking sea lice parasites from salmon.
Researchers from the University of Stirling’s Institute of Aquaculture, Loch Duart and Otter Ferry Seafish with support from the Sustainable Aquaculture Innovation Centre are studying the wrasse to determine how they react to new objects in their tank and whether this correlates with their ability to rid salmon of sea lice.
Professor Herve Migaud from the University of Stirling’s Institute of Aquaculture said that Ballan wrasse were very clever fish. “If you walk by a tank they will take an interest in you and watch you and follow,” he said. “Each has their own personality and we want to correlate which traits – namely boldness and shyness – translate into Ballan wrasse being reliable and effective at delousing salmon,” he added.
The team will also be using hydroacoustic tracking of tagged fish to compare the behaviour of experienced wild wrasse and those reared in hatcheries. This same technique can be used to monitor the salmon’s behaviour, identifying whether they encourage the wrasse to clean them.
The Aquawrasse project will run for 12 months and will also explore the optimal conditions for the wrasse such as their feed, set-up of their pens and the ratio of salmon to cleaner fish.