Sea lice infestations are among the most significant welfare and production challenges in Atlantic salmon farming, requiring integrated management approaches that minimize fish suffering.
Sea lice (Lepeophtheirus salmonis) are ectoparasitic copepods that attach to salmon skin and feed on mucus, tissue, and blood. Even moderate infestations cause chronic pain, stress, and immune suppression. Chemical treatments, while effective, can have side effects including gill damage and behavioral changes in treated fish. Mechanical removal methods like high-pressure water and thermal treatments cause acute stress. The welfare-optimal approach combines integrated pest management — including strategic fallowing, lice monitoring, cleaner fish deployment, and targeted treatment — with continuous investment in non-invasive removal technologies.