Common carp are the most produced freshwater farmed fish globally by volume, particularly in Central and Eastern Europe and Asia. Water quality management in traditional pond systems significantly determines carp welfare outcomes.
Carp in low-oxygen pond conditions show surface gasping, reduced feed intake, and chronic physiological stress. Traditional autumn harvest methods involve draining ponds until fish are packed into shallow water at high density, handled repeatedly, and transported live. Welfare improvement is achievable through aeration management, monitoring of dissolved oxygen, and modified harvest practices that reduce crowding duration and intensity.