Scientific understanding of fish pain has advanced substantially since 2000, with important implications for how we manage fish in aquaculture, angling, and wild fisheries.
The scientific consensus on fish pain has shifted dramatically in the last two decades. Early dismissals were based on the assumption that a cortex-independent pain experience was impossible — but fish show all the behavioral and physiological markers of nociceptive response that we accept as pain indicators in mammals. Whether they have subjective suffering remains philosophically contested, but the precautionary case for treating fish as though they can suffer is now compelling. The welfare implications are enormous: trillions of fish are killed annually under conditions that would be illegal for vertebrate animals in most jurisdictions.