How farmed fish are killed has significant welfare implications, with methods varying enormously in terms of the suffering caused and the speed of unconsciousness achieved.
Fish slaughter welfare has historically been neglected due to assumptions about fish sentience and the practical challenges of humane killing at scale. As evidence for fish pain and stress responses has strengthened, the welfare case for improved slaughter methods has become compelling. The current standard in many operations — ice slurry or CO2 — involves significant potential suffering before death. Electrical and percussive stunning systems that reliably achieve rapid unconsciousness represent meaningful welfare improvements that the industry has the technology to implement.