Examining the welfare gaps in intensive tilapia aquaculture and what evidence-based improvements are achievable at scale.
Tilapia welfare receives far less attention than salmon or trout farming despite their greater production volume. Their hardiness — the biological trait that makes them attractive to farmers — is misread as evidence that they are less sentient or less sensitive to poor conditions. Evidence suggests otherwise: overcrowded tilapia show fin damage, increased aggression, immunosuppression and stress hormone elevation. The welfare improvements most needed are structural — reducing stocking density, improving water quality monitoring and eliminating hormonal sex reversal — and most are achievable without prohibitive cost if mainstreamed in certification and purchasing standards.