Sea lice infestations remain one of the most significant welfare and sustainability challenges in salmon aquaculture, with emerging biological and non-chemical controls showing promise.
Sea lice cause direct physical harm through feeding on mucus, skin, and underlying tissue. Heavy infestations lead to open wounds, secondary infection, osmoregulatory disruption, and death. Welfare concerns extend to cleaner fish used as biocontrols, which are often kept in poor conditions and experience high mortality. Chemical treatments cause acute stress and have off-target environmental effects. Emerging non-chemical approaches reduce reliance on stressful treatments while addressing the root cause of infestation. Transitioning to land-based recirculating aquaculture systems eliminates sea lice entirely but requires substantial infrastructure investment.