Farmed Animals

Farmed Salmon Sea Lice Welfare Burden

Sea lice infestations are the most significant welfare and production challenge in Atlantic salmon aquaculture, causing painful skin damage to millions of fish.

Key Facts

Sea lice are ectoparasitic copepods that feed on salmon skin and mucus
Chalimus and mobile lice stages cause progressive skin lesions and ulceration
Chemical treatments like azamethiphos are toxic to non-target crustaceans
Biological control using cleaner fish like wrasse is being adopted more widely
Heavy infestations cause anemia, secondary infections, and mortality

Welfare Considerations

Salmon with heavy sea lice burdens experience chronic skin and eye lesions that are painful and debilitating. Treatment methods including chemical baths cause additional acute stress. Welfare improvements including mechanical removal methods, better site selection, and cleaner fish programs reduce but do not eliminate the sea lice welfare burden.

What You Can Do

Choose salmon with sea lice monitoring and management certification
Support research into welfare-friendly sea lice control methods
Advocate for reduced salmon farm stocking densities to lower lice pressure
Reduce salmon consumption or choose better-welfare alternatives
Support open-access publication of sea lice infestation data by farms