Atlantic salmon aquaculture has made genuine welfare improvements in some markets while persistent challenges around sea lice, crowding, and slaughter remain.
Sea lice cause progressive tissue damage that can become severe enough to expose underlying muscle and bone, representing significant chronic welfare harm. Treatment methods including bath treatments and mechanical removal procedures cause their own welfare concerns. High stocking densities cause aggression, fin damage, and chronic stress measurable through cortisol and behavioral indicators. Despite improvements in certified supply chains, the majority of global salmon is produced with minimal welfare oversight. The welfare gap between certified and uncertified salmon represents one of the largest achievable improvements through consumer purchasing decisions in aquaculture.