Aquatic Animals

Sea Lice Infestation in Farmed Salmon

Sea lice are parasitic copepods that infest farmed salmon, causing significant welfare problems and ecological damage.

Key Facts

Sea lice (Lepeophtheirus salmonis) are the main parasite of Atlantic salmon
Heavy infestations cause skin lesions, fin damage, and scale loss
Each louse passes through 8 developmental stages on the host fish
Farmed salmon produce amplified sea lice numbers affecting wild fish
Chemical treatments for sea lice include hydrogen peroxide and organophosphates

Welfare Considerations

Sea lice cause significant pain and suffering in infested salmon. They feed on skin, mucus, and blood, creating open wounds vulnerable to secondary infection. Heavy burdens cause physical weakening, impaired osmoregulation, and compromised immune function. Treatment methods including medicinal bathing and mechanical removal also cause acute stress. Sustainable solutions require reducing farm densities and improving fallowing practices.

What You Can Do

Choose salmon from producers with low sea lice counts and sustainable practices
Look for certifications indicating responsible aquaculture practices
Support research into biological control methods using cleaner fish
Advocate for stricter regulatory thresholds for sea lice numbers
Reduce salmon consumption or choose alternative protein sources