The smoltification phase when juvenile salmon transition from freshwater to seawater tolerance is a physiologically demanding period with significant welfare implications for how the transition is managed in commercial aquaculture.
Smolt welfare is a critical but often overlooked phase in salmon farming welfare. The physiological demands of smoltification make this a period of elevated vulnerability when management decisions have outsized welfare consequences. Poor transfer timing, rough handling, and inadequate post-transfer monitoring can result in welfare problems that affect the entire subsequent grow-out period. Welfare-centred smolt management uses validated readiness criteria before transfer, minimises handling through good facility design, monitors post-transfer welfare indicators closely, and allows adequate recovery time before resuming normal feeding schedules.