Farm Animal Welfare

Farmed Salmon Sea Lice Resistance

How sea lice resistance to treatments threatens salmon welfare and what integrated approaches can address it.

Key Facts

Sea lice resistance to medicinal treatments has developed in populations in Norway and Scotland
Resistant sea lice cause greater welfare harm as effective treatments are unavailable
Non-medicinal methods including cleaner fish and laser systems are increasingly important
Genetic selection for sea lice resistance in salmon is an active research area
Fallowing and synchronised treatment protocols slow resistance development

Welfare Considerations

Sea lice treatment resistance is a growing welfare crisis in salmon aquaculture. When effective treatments are unavailable, sea lice infestation causes chronic skin damage, secondary infection, and physiological stress in farmed salmon. Preventing resistance development through responsible treatment use, and investing in non-medicinal alternatives, is both a welfare and an economic priority for the industry.

What You Can Do

Choose salmon from farms that publish sea lice treatment data
Support research into non-medicinal sea lice control methods
Advocate for mandatory sea lice resistance monitoring and reporting in aquaculture regulations