Lumpsuckers are deployed in salmon cages as cleaner fish to control sea lice. Their welfare as a farmed species deserves consideration alongside their functional role.
Lumpsucker welfare in salmon cages is severely compromised by high mortality rates from salmon predation, stress, and inadequate adaptation to cage conditions. As benthic fish deployed in mid-water pelagic environments, lumpsuckers face constant environmental mismatch. Providing refuge structures at the cage bottom where they can rest reduces predation and stress. Adequate feed provision reduces competition-related mortality. The welfare of these cleaner fish is increasingly recognised as an ethical concern alongside their practical utility in reducing sea lice chemical treatments.