Atlantic salmon in open-net cage aquaculture face chronic welfare problems from high-density confinement, sea lice infestations, and disease that affect millions of fish annually.
Farmed salmon welfare is compromised at nearly every stage of production. High density prevents natural swimming behaviors, while the constant presence of sea lice causes tissue damage equivalent to open wounds covering significant portions of the body. Treatments — chemical baths, freshwater immersion, or mechanical removal — cause additional acute distress. Salmon are capable of learning, show stress responses, and demonstrate preferences in controlled environments, suggesting meaningful capacity for suffering. The welfare case for transitioning to land-based closed containment systems is strong, though economic incentives currently favor open-net cages.