Sea lice management is the central welfare and ecological challenge in Atlantic salmon farming, with new biological and physical methods offering alternatives to chemical treatments.
Sea lice management in Atlantic salmon represents a welfare challenge that is simultaneously one of the most researched and one of the least resolved in aquaculture. Chemical treatments reduce lice burdens but cause significant handling stress and secondary mortality in the treated fish. Cleaner fish provide biological control but themselves face welfare challenges in commercial pen environments where they are poorly understood ecologically. Laser targeting is promising but not yet at full commercial scale. Closed containment eliminates the problem entirely — but at capital costs that most operators cannot bear without policy support. The welfare trajectory in this area is positive but slow.