Farmed Salmon Pre-Slaughter Welfare

The welfare of farmed Atlantic salmon in the hours before slaughter, including crowding, fasting, and stunning method standards.

Key Facts

Approximately 3.5 million tonnes of farmed Atlantic salmon are produced globally each year
Pre-slaughter crowding during harvest is among the most acutely stressful events in the salmon farming cycle
Fasting periods of 3-10 days before slaughter are standard practice to empty digestive tracts for processing
Percussion, electrical, and carbon dioxide stunning methods are used with significantly different welfare profiles
Percussion stunning followed by gill cutting is considered best practice by most welfare authorities
CO2 stunning causes an aversive experience in salmon before loss of consciousness and is increasingly replaced
Some markets now require third-party welfare certification that includes pre-slaughter and slaughter standards

Welfare Considerations

Pre-slaughter salmon welfare involves a sequence of acute stressors — crowding, netting, pump transfer, fasting, and the final stunning and killing procedure — each of which carries measurable welfare costs for animals whose capacity for negative experience is scientifically well-supported. The improvements available are not hypothetical: percussion and electrical stunning cause rapid loss of consciousness; CO2 does not. Pre-slaughter crowding can be minimized through gradual harvest approaches. Fasting periods can be optimized to balance gut clearance with unnecessary starvation. These improvements are technically feasible and increasingly demanded by welfare-conscious buyers. The remaining challenge is ensuring they become the industry norm rather than the premium exception.

What You Can Do

Choose salmon products certified by standards that specify pre-slaughter and slaughter welfare requirements
Avoid salmon products from producers who use CO2 as the sole stunning method without equivalent alternatives
Advocate for mandatory stunning standards in aquaculture licensing in your country
Support organizations like the Norwegian Animal Protection Alliance working to reform salmon slaughter practices
Write to major salmon retailers asking about their supplier requirements for pre-slaughter welfare