The question of whether aquatic invertebrates including crabs, shrimp, and lobsters experience pain remains scientifically contested. The precautionary principle guides emerging policy.
The aquatic invertebrate pain debate represents the frontier of welfare science where evidence is genuinely uncertain but has significant welfare implications given the scale of global crustacean fishing and aquaculture. The precautionary principle - extending welfare protections under uncertainty - is gaining traction in both science and policy. The welfare cost of being wrong about sentience vastly exceeds the cost of unnecessary precaution.