Interactions between farmed and wild salmon create disease transmission pathways that affect both wild population welfare and the conservation of already-depleted wild stocks.
The interaction between farmed and wild salmon creates welfare harm that extends beyond the farm boundary. Wild juvenile salmon encountering sea lice from nearby net-pen operations face lethal parasite burdens — a welfare harm imposed on wild animals by industrial activity they cannot avoid. Wild salmon populations already depleted by overfishing, habitat loss, and climate change face additional mortality from disease pressure originating in farms. The conservation welfare framework recognizes that population-level threats to wild salmon represent welfare harm at scale — future individuals who will never exist because populations collapsed. Closed-containment technology offers a technical solution, requiring regulatory and economic drivers for adoption.