Farmed Salmon Welfare at Processing: Stunning and Slaughter

Welfare at harvest is one of the most consequential welfare decisions in salmon farming. Effective stunning and humane slaughter are critical for millions of fish.

Key Facts

Atlantic salmon are typically harvested using percussion stunning followed by gill cutting
Effective stunning must render fish immediately insensible before any nociception can occur
Carbon dioxide immersion - once common - is now recognised as aversive and being phased out
Electrical stunning requires correct waveform, frequency, and duration for full insensibility
Post-slaughter gill bleeding should occur while fish remain insensible
Welfare at harvest is a growing focus of certification schemes including Global Salmon Initiative standards

Welfare Considerations

Slaughter welfare for farmed salmon represents one of the most consequential welfare interventions in aquaculture given the scale of production. Millions of salmon are harvested annually and the method of stunning and slaughter determines whether each experiences distress and pain in their final moments. Percussion stunning, when correctly applied, provides immediate insensibility. However, application must be precise - mis-stunning causes pain without rendering the fish insensible. Industry investment in automated stunning equipment with built-in quality control has improved consistency. Welfare certification increasingly requires third-party audits of harvest practices.

What You Can Do

Choose certified salmon from schemes requiring welfare-positive harvest practices
Support research into reliable stunning effectiveness monitoring in aquaculture
Advocate for mandatory welfare standards at salmon harvest facilities
Learn about humane slaughter requirements from organisations like the Fish Welfare Initiative