Sea Lice and Salmon Welfare: 2025 Management Update

Current science and practice for managing Lepeophtheirus salmonis to protect Atlantic salmon welfare.

Key Facts

Sea lice are the primary welfare challenge in Atlantic salmon farming globally
Adult lice feed on salmon skin and mucus — causing lesions, stress, and secondary infection
Biological control using cleaner fish (wrasse and lumpfish) is now widespread
Treatment resistance to multiple medicines is an increasing welfare and production concern

Welfare Considerations

Sea lice welfare management in 2025 uses an integrated approach — biological control through cleaner fish, non-medicinal methods (thermolicer, hydrolicer, laser), and medicines only when biological approaches are insufficient. Welfare-informed sea lice management keeps lice counts below welfare thresholds, monitors cleaner fish welfare (they too are farmed animals with welfare needs), and invests in genetic resistance breeding. Resistance to existing medicines makes welfare sustainability challenging.

What You Can Do

Support Atlantic salmon certification requiring integrated sea lice management with defined welfare thresholds
Advocate for cleaner fish welfare standards as part of salmon aquaculture certification
Choose salmon from producers with documented, transparent sea lice management practices