Pre-slaughter stunning for farmed fish is the single most impactful welfare improvement available in aquaculture. Understanding current practices and better alternatives is essential for welfare advocacy.
Pre-slaughter stunning represents the most important single welfare intervention available in aquaculture. Without stunning, fish remain conscious through the killing process — whether that is asphyxiation in air (which can take 10-15 minutes), CO2 exposure (which causes aversive distress before unconsciousness), or ice slurry immersion. Electrical stunning, properly applied, renders fish immediately unconscious. The welfare gain is the elimination of a highly stressful, potentially painful dying process. Consumer demand for certified products requiring pre-slaughter stunning, and retailer commitments to require it in their supply chains, are the most effective mechanisms for driving adoption. This is an area where welfare improvement is technically straightforward — the barrier is commercial willingness, not technical capacity.