The welfare of farmed fish at slaughter depends critically on the method used, with significant variation from rapid and humane to prolonged and distressing.
Fish slaughter welfare is one of the most tractable large-scale improvements possible in aquaculture: replacing inhumane methods with pre-slaughter stunning affects the experience of billions of animals annually. The technology exists; the barrier is regulation and cost. Percussive stunning or electrical stunning before slaughter renders fish instantaneously unconscious, eliminating the suffering of conscious suffocation or bleeding out. Progressive retailers and certification schemes increasingly require these methods, creating market incentives for producers to adopt them. Advocacy for mandatory stunning requirements in aquaculture legislation is high-impact.