What research reveals about crayfish pain and stress responses and the welfare implications.
Crayfish welfare science has advanced rapidly, moving from dismissal of crustacean sentience to serious consideration of their capacity for pain and anxiety. The evidence is not definitive but is substantial enough to warrant precautionary concern. Crayfish show nociceptive responses, learning from aversive experiences, and states that respond to anxiolytic medications in ways analogous to anxiety. The scale of crayfish production for food — billions of animals annually — gives urgency to resolving the welfare question. Regulatory moves in the UK and EU to include decapod crustaceans in animal welfare protections represent a significant precautionary step ahead of complete scientific certainty.