Wrasse and lumpfish are used as cleaner fish in Atlantic salmon and sea bass farms to control sea lice. Their welfare needs are often given lower priority than those of the farmed host species.
Cleaner fish welfare is an overlooked component of salmon aquaculture sustainability. Wild-caught wrasse face capture stress and rapid environmental change. In cages, aggressive interactions with salmon, exhaustion from continuous cleaning work, and inadequate refugia cause high mortality. Industry guidance on cleaner fish care has improved but is inconsistently applied across farms.