The pre-slaughter period at salmon harvest involves crowding, pumping, and transport to the kill station — welfare science identifies each stage as an acute stressor requiring specific mitigation.
Pre-slaughter welfare encompasses multiple sequential stressors. Crowding nets restrict movement and deplete oxygen. Pumping through suction and blow systems causes pressure trauma and scale loss. Transfer to the kill station involves further handling. Cumulative stress from each stage adds to the welfare cost before the killing event itself. Minimising crowding duration, optimising pump flow rates, and reducing the time between initial crowding and stunning all improve pre-slaughter welfare.