Farm Animals

Farmed Salmon Sea Lice and Cleaner Fish Welfare

Sea lice infestations cause serious welfare harm to farmed salmon, and cleaner fish used as biological control themselves face significant welfare challenges.

Key Facts

Sea lice infestations cause open sores, scale loss and immune suppression in salmon
A single female louse can produce 500-1,000 eggs every 72 hours in warm water
Wrasse and lumpfish are used as cleaner fish to eat lice directly from salmon skin
Cleaner fish face high mortality rates of 50-80% per production cycle in salmon pens
Hunger, injury from salmon, and starvation at treatment time are major welfare concerns

Welfare Considerations

The welfare calculus of cleaner fish is complex and troubling. Wrasse and lumpfish are taken from wild populations or bred specifically to serve as biological pest control for salmon, and their own welfare is often poorly protected. Cleaner fish need appropriate shelter, compatible social grouping, and supplement feeding when lice loads are insufficient for their nutritional needs. Improved sea lice monitoring and prevention reduces reliance on cleaner fish.

What You Can Do

Support aquaculture welfare certification schemes that include cleaner fish standards
Choose salmon from producers with published integrated pest management programs
Advocate for improved cleaner fish welfare regulations through aquaculture bodies
Reduce farmed salmon consumption or choose responsibly sourced alternatives