Aquaculture

Sea Lice Infestation in Farmed Salmon: A Welfare Crisis

Sea lice are the most significant welfare and economic challenge in salmon aquaculture, causing chronic pain, tissue damage, and stress to millions of fish annually.

Key Facts

A single female sea louse produces 500-1000 eggs in her lifetime
Heavy infestations cause open wounds, hemorrhage, and osmotic stress
Treatment chemicals including hydrogen peroxide cause significant fish mortality
Cleaner fish such as wrasse and lumpfish are used as biological controls
Sea lice from farms spread to wild salmon populations in adjacent waters

Welfare Considerations

Sea lice infestations cause chronic suffering through tissue damage, constant irritation, and the physiological stress of immune response. Treatment procedures including bath treatments cause additional acute distress. The scale of the problem, affecting hundreds of millions of fish annually, makes sea lice welfare a global priority.

What You Can Do

Choose farmed salmon with credible welfare certification schemes
Support investment in closed containment aquaculture systems
Advocate for sea lice monitoring thresholds and treatment regulations
Reduce salmon consumption or switch to lower-impact farmed species
Support research into sea lice vaccines and genetic resistance