Carp is the most farmed fish species globally by volume, particularly in Asia, but welfare standards for carp production are less developed than for salmon or trout.
The welfare of farmed carp receives minimal regulatory attention globally, partly because their hardiness allows survival in conditions that would kill more sensitive species. This survival capacity masks welfare problems: carp in severely oxygen-depleted water experience significant physiological stress before reaching the threshold of acute distress that causes visible surface gulping. High stocking densities in intensified carp ponds cause chronic crowding stress and elevated disease susceptibility. The sheer scale of carp production, exceeding all other farmed fish species combined, means that welfare improvements even of modest effect size would benefit an enormous number of sentient animals. Developing and implementing evidence-based welfare standards for carp production is an urgent priority.