How expanding evidence on fish cognition and sentience is reshaping our understanding of their capacity for suffering and what it means for aquaculture and fishing.
The scientific consensus on fish sentience has shifted substantially over the past two decades. While the mechanisms of pain experience in fish differ from mammals, the precautionary principle applied to the sheer number of fish affected by human activity makes fish welfare one of the most numerically significant welfare issues in existence. Improving fish welfare requires changes at every level: how fish are caught (reducing bycatch and improving slaughter methods in wild-catch fisheries), how they are farmed (better stocking densities, water quality, and pre-slaughter stunning), and how they are transported and handled. Consumer awareness of fish sentience, combined with regulatory requirements for humane handling and slaughter, can drive meaningful improvement in the welfare of an enormous number of sentient beings.