Welfare considerations in farmed common carp production, the world most widely farmed fish species by volume, with particular attention to Central and Eastern European systems.
Carp aquaculture welfare occupies a complicated space between extensive traditional farming with reasonable behavioral freedom and intensive industrial production with welfare-compromising conditions. The species hardiness has historically been used to justify minimal attention to welfare, but hardiness does not equal insensibility — carp experience chronic stress from poor conditions and show measurable physiological responses to noxious stimuli. Traditional Christmas carp markets in Central Europe, where fish are held in bathtubs for days before being killed at home without stunning, represent a particularly poor welfare practice that cultural tradition has shielded from scrutiny. Evidence-based improvements including effective stunning before slaughter, reduced holding period before killing, and minimum water quality standards in marketing channels are achievable welfare advances.