Animal Welfare in Aquaculture Slaughter: Humane Killing of Farmed Fish

Slaughter methods for farmed fish vary widely in their welfare implications, and industry standards for humane killing at harvest are inconsistently applied.

Key Facts

Common slaughter methods for farmed fish include asphyxiation in air, CO2 narcosis, chilling in ice slurry, and percussive or electrical stunning
The European Food Safety Authority concluded that most current commercial fish slaughter methods cause significant suffering
Percussive stunning followed by immediate bleeding delivers rapid insensibility and is considered the gold standard for small farmed fish
Electrical stunning systems designed specifically for salmon have been validated and are in commercial use in Norwegian aquaculture
Asphyxiation in air — simply leaving fish to suffocate — is among the most common and welfare-poorest methods still in use
Certification standards including RSPCA Assured require pre-slaughter stunning for farmed fish in their supply chains

Welfare Considerations

Fish slaughter welfare is one of the most significant and correctable welfare failures in the food system. Billions of farmed fish are killed annually using methods that cause prolonged suffering when validated humane alternatives are available. The economic barrier to implementing stunning is real but modest relative to total production costs. The welfare science is unambiguous that asphyxiation in air, CO2 narcosis, and live chilling without prior stunning cause significant suffering. Consumer demand for certified humane slaughter standards in fish products is the most effective lever for industry adoption of better methods.

What You Can Do

Choose farmed fish products with welfare certifications that require pre-slaughter stunning
Ask retailers and restaurants about slaughter methods used for the fish in their supply chains
Support certification bodies that develop and require validated humane slaughter standards for farmed fish species
Advocate for regulatory requirements for pre-slaughter stunning in all commercial fish aquaculture operations