Environmental enrichment for rainbow trout in aquaculture improves welfare by providing structural complexity that enables more natural behaviour and reduces aggression and stress.
Rainbow trout enrichment science demonstrates that even relatively simple environmental modifications can significantly improve farmed fish welfare. Structural enrichment providing shelter and flow complexity enables trout to express more natural habitat use behaviour. The welfare improvements are measurable through reduced aggression, lower cortisol levels, and better immune competence. The practical challenge is scaling enrichment to commercial systems while maintaining operational efficiency. Research into enrichment delivery systems that can be managed at commercial scale is the critical translational step between laboratory demonstration and farm implementation.