Farmed Salmon Lice Cleaner Fish Welfare

Wrasse and lumpfish used to eat sea lice from farmed salmon face severe welfare challenges as an overlooked species within Atlantic salmon aquaculture systems.

Key Facts

Approximately 30 million cleaner fish including wrasse and lumpfish are used in Norwegian salmon farming annually
Most wrasse used are wild-caught rather than captive-bred, with capture stress and wild population depletion concerns
Cleaner fish mortality rates in salmon farms are extremely high -- some estimates suggest 50-80% annual mortality
Wrasse and lumpfish have specific welfare needs including hiding places, appropriate temperature, and conspecific grouping
Net pen environments are fundamentally unsuitable for some wrasse species which are cold-intolerant

Welfare Considerations

Cleaner fish welfare is perhaps the most neglected welfare issue in Atlantic salmon aquaculture. These small fish -- wrasse species and lumpfish -- are introduced to salmon pens to eat sea lice, but their own welfare needs are almost universally ignored. They are typically wild-caught (adding capture welfare concerns), held in conditions without appropriate shelter or social grouping, and exposed to temperature extremes that exceed their physiological tolerance. Annual mortality rates are catastrophically high. The reliance on cleaner fish as a sea lice solution is itself a welfare compromise: a better alternative is reducing lice pressure through closed containment or resistance breeding, which would eliminate cleaner fish welfare problems entirely.

What You Can Do

Support salmon from closed-containment or RAS farms that do not use cleaner fish
Advocate for welfare standards specific to cleaner fish in salmon farming certification
Ask salmon suppliers about their cleaner fish welfare policies and mortality rates
Support research into salmon lice management alternatives that eliminate cleaner fish dependency