Aquaculture

Farmed Salmon Delousing Treatment Welfare

Sea lice treatments in salmon farming cause significant welfare concerns, with crowding, handling, and thermal or chemical exposure creating stress and injury.

Key Facts

Thermolicer systems expose salmon to water at 34C for 30-60 seconds to kill sea lice
Freshwater delice treatments cause osmotic stress and require careful management
Hydrogen peroxide treatments at high doses cause anaesthetic-level effects
Crowding for treatment causes stress even before the treatment itself
Cleaner fish (wrasse and lumpfish) offer biological control reducing treatment need

Welfare Considerations

Sea lice treatments are a major source of acute welfare impact in salmon farming. Thermal, chemical, and mechanical treatments all cause stress and can cause mortality. Reducing treatment frequency through biological control and lice-resistant genetics is both a welfare and production priority.

What You Can Do

Choose salmon from farms investing in biological lice control methods
Support certification schemes that require lice monitoring and minimise treatment
Advocate for welfare assessment of delousing procedures in aquaculture regulations