The science of fish pain has advanced dramatically in recent years, with implications for how we manage fishing, aquaculture, and research involving fish.
The science of fish pain has moved from dismissal to genuine uncertainty and increasingly toward cautious acceptance that fish can experience something analogous to pain. The evidence encompasses nociceptor anatomy, neural processing, behavioural avoidance, analgesic responsiveness, and interference with normal behaviour by noxious stimuli. The precautionary principle — that we should extend welfare protections when there is genuine scientific uncertainty about the capacity for suffering — argues strongly for treating fish as sentient animals. The practical implications are substantial: billions of fish experience capture, transport, crowding, and slaughter annually without meaningful welfare consideration. Beginning to apply welfare thinking to fish would represent one of the largest potential improvements in animal welfare currently achievable.