Tilapia is now the third most farmed fish globally — intensive production at high densities causes aggression, fin damage, and chronic stress in this social and territorial species.
Tilapia welfare in intensive systems is compromised by crowding-induced aggression and territorial conflict. Fin erosion from aggression causes pain and infection risk. Hormonal sex reversal — feeding methyltestosterone to fry — is a welfare concern requiring scrutiny. Rapid water quality deterioration in warm-water ponds causes hypoxia and gill disease. Lower density, better water management, and enrichment reduce these harms.