Electrical Stunning for Fish: Best Practice

Electrical stunning is the most humane available method for rendering fish unconscious before slaughter, but correct application requires species-specific parameters and careful monitoring.

Key Facts

Electrical stunning causes immediate loss of consciousness in fish when correctly applied
Parameters including current, frequency, and exposure time must be calibrated for each species and size class
Under-stunning causes pain without unconsciousness; over-stunning causes spinal damage and haemorrhage
The Humane Slaughter Association provides guidance on electrical stunning parameters for common farmed fish
Percussion stunning followed by pithing is used as a backup method to ensure irreversible loss of consciousness

Welfare Considerations

Electrical stunning, when correctly calibrated, can induce rapid, painless unconsciousness in fish prior to slaughter. The challenge is species-specific variation — what works for rainbow trout does not work for Atlantic salmon at the same settings. Poorly calibrated stunning causes tetanic convulsions that look like unconsciousness but are not. Post-stun monitoring and backup methods are essential quality controls. Investment in species-specific stunning research and industry-wide parameter sharing would significantly improve the welfare of billions of farmed fish at slaughter.

What You Can Do

Advocate for mandatory electrical stunning standards in farmed fish slaughter regulations
Support research into species-specific stunning parameters for commercially important aquaculture species
Choose farmed fish from producers who demonstrate use of verified humane slaughter methods
Engage with aquaculture sector bodies about their fish slaughter welfare commitments
Support the Humane Slaughter Association's fish welfare work