Atlantic salmon are slaughtered in their millions daily without pre-stunning in many operations. Evidence for fish sentience makes improved slaughter welfare both ethically necessary and technically achievable.
Salmon slaughter welfare is one of the highest-impact intervention points in aquaculture welfare given the scale of production. Without pre-stunning, salmon in ice slurry experience cold shock and hypoxia for 1-6 minutes while remaining conscious — a period during which behavioral and physiological evidence clearly indicates suffering. The technical solutions exist and are commercially deployed: percussive stunning with captive bolt delivers a rapid blow to the head causing immediate insensibility; electrical stunning (AQUI-S or similar) at appropriate voltage and frequency produces rapid loss of consciousness; CO2 exposure at high concentrations produces rapid insensibility. The remaining welfare question is implementation: ensuring stunning is effective for all fish rather than a proportion, and that properly stunned fish are killed before recovery of consciousness. Consumer pressure through product certification, retailer supply chain requirements, and regulatory mandates are all driving adoption of pre-slaughter stunning in salmon production.