The capacity of fish to experience chronic pain — not just acute nociception — has significant welfare implications for aquaculture and fisheries. Emerging evidence supports that fish have the neural architecture for persistent pain states.
If fish experience chronic pain, the welfare implications for aquaculture are profound. Billions of fish are farmed under conditions that may generate persistent painful states — parasite infestations, injuries, overcrowding-related fin damage — without any analgesia or welfare monitoring for pain. The precautionary principle strongly supports treating fish as potential chronic pain sufferers and managing aquaculture accordingly. This means monitoring for pain indicators, treating parasitic infestations promptly, and developing analgesic protocols for aquaculture species. The scientific consensus on fish sentience has shifted substantially in the past decade and should drive policy change.