Stocking density is one of the most significant welfare factors in fish farming. Understanding the welfare impacts of crowding informs both industry standards and consumer choices.
Crowding in fish farming is a welfare problem that is simultaneously a biological stress, a behavioral constraint, and a disease risk. At high densities, fish cannot perform normal swimming patterns, are more frequently involved in aggressive interactions, experience chronic social stress, and are more susceptible to infectious disease spread. Welfare science has established clear density-welfare relationships: reducing stocking density produces measurable improvements in behavior, physiology, and health. Consumer demand for welfare-certified seafood and advocacy for stronger regulatory stocking density limits are both important levers for change.