The handling and slaughter process for farmed Atlantic salmon involves significant welfare risks at each stage, from crowding during harvest to the slaughter method itself.
Atlantic salmon slaughter welfare has received more regulatory and scientific attention than almost any other farmed fish species, partly because of the industry scale and partly because salmon welfare science is relatively well-developed. Despite this attention, significant welfare gaps remain. Pre-slaughter crowding to facilitate harvesting concentrates thousands of fish in rapidly deteriorating water conditions, causing hypoxia and stress that elevate cortisol before any slaughter even begins. Percussion stunning using spiked head plates is effective when calibrated correctly but requires trained operators. Electrical stunning systems that render fish unconscious before killing are increasingly adopted by welfare-certified producers. Post-stun killing — gill cutting or spiking — must occur immediately to prevent recovery. Welfare auditing at slaughter is among the most effective leverage points for improvement.