Wild Atlantic salmon face multiple welfare threats from fishing, pollution, and sea lice from fish farms. Conservation measures that protect populations also protect individual fish welfare.
Wild salmon welfare involves both individual and population-level considerations. Catch-and-release angling causes measurable physiological stress — cortisol elevation, oxygen debt, and physical exhaustion — and carries mortality risk, particularly in warm water conditions. The welfare harm of individual angling interactions must be weighed against the conservation benefit of recreational fishing supporting protection of salmon rivers and populations. Sea lice from fish farms cause welfare harm to wild salmon smolts, reducing their survival as they migrate to sea. Population-level decline from multiple threats represents a large-scale welfare harm affecting millions of individual fish annually. Conservation measures that maintain healthy populations also protect individual fish from the welfare costs of population stress.