Tilapia is the most widely farmed fish in tropical countries, with welfare challenges concentrated in stocking density, water quality, and the welfare of this sentient and socially complex species.
Tilapia welfare is often overlooked because the species is considered hardy and adaptable — but adaptability to poor conditions does not mean those conditions are welfare-neutral. Territorial aggression at high stocking densities causes chronic stress and physical injury; dominance hierarchies mean subordinate fish may be in persistent states of stress. Water quality fluctuations, particularly oxygen crashes, cause acute suffering in mass mortality events. As tilapia farming expands to meet global protein demand, welfare standards need to accompany that expansion rather than being addressed retrospectively.