Slaughter methods for farmed fish vary enormously in their welfare implications, with electrical stunning, percussive stunning, and carbon dioxide showing very different welfare profiles compared to the ice slurry methods still widely used.
Fish slaughter welfare has improved substantially in leading salmon aquaculture markets through retailer and certification scheme pressure, demonstrating that consumer-driven welfare improvement is achievable even in aquatic species that attract limited public sympathy. The continued dominance of ice slurry killing across most farmed fish species globally represents a major welfare gap — a method known to cause prolonged suffering continues to be used because alternatives require investment and awareness. Electrical stunning systems now exist for salmon, trout, and several other species and are economically viable at commercial scale. The welfare case for transitioning to humane slaughter across all farmed fish species is clear, requiring continued consumer, retailer, and regulatory pressure to drive adoption.