The crowding of salmon before harvest is a high-risk welfare period requiring careful management to minimise physiological stress and prevent avoidable mortality.
Pre-harvest crowding is a period of acute stress for salmon that is often inadequately managed in commercial operations. Fish are compressed to high density, unable to escape, and showing clear signs of physiological and behavioural stress. The welfare impact can be reduced through slower, graduated crowding procedures, minimum time at high density, and effective stunning that rapidly renders fish insensible.