Tilapia is the world's second most farmed fish after carp. Their welfare in intensive production systems raises questions about crowding, water quality, and slaughter methods.
Tilapia welfare in intensive aquaculture is compromised by high stocking densities, variable water quality, and inhumane slaughter methods. Crowding beyond welfare thresholds causes chronic stress measurable through cortisol elevations and behavioral indicators including reduced feeding and aggression. Asphyxiation — simply removing fish from water — causes progressive air hunger as oxygen levels in tissues fall, a process taking several minutes. Ice slurry slaughter is faster but fish remain conscious for 30–150 seconds before losing consciousness from cold. Electrical stunning before slaughter is achievable for tilapia and provides near-instantaneous unconsciousness. As with other farmed fish, welfare improvements in tilapia production require both regulatory standards and consumer demand for certified products.