Common carp is the single most farmed fish species globally by volume, yet receives almost no welfare attention despite growing evidence of its sentience.
Carp welfare represents the largest unaddressed welfare gap in global aquaculture. With 30 million tonnes produced annually — predominantly in systems with minimal welfare oversight — the aggregate welfare impact of poor conditions is vast. Traditional pond polyculture systems have some natural behavior benefits (adequate space, substrate, varied food sources) compared to intensive cage systems, but harvest methods are consistently welfare-poor. Pond draining causes crowding stress, oxygen depletion, and injury. Live fish transport over long distances subjects fish to overcrowding, temperature fluctuation, and poor water quality. The near-universal absence of stunning before slaughter means billions of carp die from asphyxiation or ice shock while fully conscious.