Electrical, percussive, and CO2 stunning methods for farmed fish are being evaluated and standardized, with significant welfare implications for the billions of fish killed in aquaculture and recreational fisheries annually.
Fish stunning welfare is a rapidly developing field as evidence of fish pain capacity has grown. Traditional slaughter methods including ice slurry immersion and CO2 asphyxiation cause significant suffering if fish experience pain. Electrical stunning that renders fish insensible before killing represents a substantial welfare improvement. The challenge is implementing effective stunning across diverse aquaculture species and scales of production. Norway's mandatory stunning requirement for farmed salmon represents the strongest regulatory framework globally, with other countries lagging significantly behind.