Salmon Lice Management Welfare in Aquaculture

Sea lice infestations in farmed salmon cause suffering and require treatments whose welfare implications for both target and non-target species require careful management.

Key Facts

Sea lice are the most significant welfare and economic challenge in salmon aquaculture
Hydrogen peroxide bath treatments cause stress and occasional mortality
Mechanical lice removal by Thermolicer causes gill damage and stress in treated fish
Cleaner fish including wrasse and lumpsucker have welfare concerns in their own right
Organophosphate treatments are toxic to crustaceans and non-target marine life

Welfare Considerations

Untreated lice infestations cause open lesions, secondary infections, and reduced immune function in infested salmon. Thermal treatments involve exposure to warm water causing gill damage. Mechanical treatments cause physical trauma. Freshwater treatments cause osmotic stress. Cleaner fish used as biological control are often wild-caught, transported, and kept in conditions poorly suited to their needs. Finding the balance between lice welfare harm and treatment welfare harm is an active research area.

What You Can Do

Support research into welfare-sparing sea lice treatments
Advocate for cleaner fish welfare standards in salmon farms using biological control
Choose salmon from farms with documented integrated sea lice management
Donate to salmon welfare research programs
Engage with aquaculture associations on lice treatment welfare assessment frameworks