July 30, 2021 — Researchers at the University of Stirling have developed a new tool that fish farmers can use to improve the welfare of lumpfish—a species crucial to tackling the problem of sea lice in salmon.
Lumpfish are increasingly being used by the salmon industry as a ‘cleaner fish’ to remove parasitic sea lice, which cost the Scottish salmon industry alone an estimated £40m per year.
Because they are a relatively new fish to aquaculture, researchers are still establishing the optimum conditions for lumpfish welfare.
In a new study, a team led by Dr. Sonia Rey Planellas at the University of Stirling’s Institute of Aquaculture has established the correlation between lumpfish growth weights and welfare, and turned it into a tool farmers can use to assess the health of the fish and take remedial action if required.
Dr. Rey Planellas says that “at the moment, in the UK we use Operational Welfare Indicators (OWIs) for fish welfare, but lumpfish are a different shape to many other fish, so it’s about identifying the best indicators for each species.”
“Fin damage is typically the indicator that is used, but in this study we found a more useful indicator was the correlation between growth weight relative to size and welfare.”