Common carp is one of the world's oldest and most widely farmed fish species. Their welfare in extensive and semi-intensive pond systems depends on stocking density, water quality, and handling practices.
Carp welfare spans a broad spectrum depending on farming system and cultural context. At best, extensive polyculture systems with low stocking densities, good water quality, and natural forage create relatively low-stress conditions. At worst, overcrowded pond systems, prolonged live transport in inadequate conditions, and live display in markets without water quality management cause considerable welfare harm. The practice of selling live carp in buckets or shallow containers in markets — common across Central and Eastern Europe and parts of Asia — exposes fish to hypoxia, physical injury, and chronic stress. Pre-slaughter stunning is not standard practice for carp in most producing countries, meaning fish are typically killed by asphyxiation or physical methods that may involve prolonged consciousness. Traditional Christmas carp practices in Central European countries have prompted welfare campaigns focused on improving slaughter methods.