Nile tilapia is the second most farmed fish globally and faces welfare challenges from high stocking densities, aggression and water quality management in intensive systems.
Nile tilapia welfare in intensive production involves significant trade-offs between economic stocking density and fish welfare. Tilapia are social animals with dominance hierarchies that high stocking density prevents from forming normally, causing chronic social stress and aggression. The hormonal sex reversal of fry (to produce all-male populations) raises welfare questions about the process. Improved water quality management and density reduction improve welfare and often production efficiency. Welfare standards for tilapia farming are underdeveloped relative to its scale and importance.