Aquaculture

Aquaculture Cleaner Fish Welfare

Wrasse and lumpfish are deployed in salmon cages to eat sea lice, but their welfare is severely compromised in aquaculture environments not designed for these species.

Key Facts

Around 30 million cleaner fish are deployed annually in Norwegian and Scottish salmon farms
Wrasse are demersal reef fish with complex habitat requirements entirely absent from sea cages
Mortality rates of cleaner fish can exceed 80% per production cycle
Lumpfish are killed with salmon at harvest with no species-specific welfare consideration

Welfare Considerations

Wrasse removed from complex reef habitats and placed in open water cages cannot fulfil basic behavioural needs including shelter-seeking, substrate browsing and reef-associated resting. They experience chronic stress in an alien environment. High mortality indicates welfare failure. Lumpfish slaughter methods are poorly adapted to their biology. Cleaner fish welfare is almost entirely absent from aquaculture welfare discourse.

What You Can Do

Advocate for cleaner fish welfare standards in aquaculture certification schemes
Support research into habitat enrichment for cleaner fish in sea cage environments
Choose salmon from producers that publish cleaner fish welfare and mortality data
Back development of non-biological sea lice control alternatives to reduce cleaner fish reliance