Crayfish farming is expanding globally, raising new welfare questions about a crustacean whose sentience and pain capacity are increasingly recognized by researchers.
Farmed crayfish occupy a welfare grey zone: their sentience is better supported by science than that of most invertebrates, yet welfare standards in crayfish farming are almost nonexistent. High stocking densities cause elevated aggression, territorial disputes, and limb loss — sources of suffering whose significance depends on the extent of crayfish sentience, which remains contested. Slaughter methods — particularly boiling alive — are of significant concern if crayfish experience pain. Best practice for welfare-conscious crayfish farming includes providing shelter structures to reduce aggression, lower stocking densities, and using electrical stunning before slaughter. Research investment is needed to resolve remaining sentience questions and develop validated welfare indicators for this rapidly growing industry.