Pre-slaughter handling of Atlantic salmon — crowding, fasting, and transport — creates significant welfare challenges requiring evidence-based management to minimize suffering.
Pre-slaughter welfare for Atlantic salmon receives more regulatory and industry attention than for most farmed fish species, partly because stress-related flesh quality problems create economic incentives aligned with welfare improvement. The crowding, transport, and handling sequence before slaughter subjects salmon to progressive stress that accumulates in measurable cortisol elevation and behavioral indicators of negative affect. Ice slurry killing without prior stunning extends this stress into the killing phase — fish placed in ice slurry show behavioral swimming in circles for 4-9 minutes before loss of consciousness. Electrical stunning achieves immediate insensibility, eliminating this period of conscious distress. The welfare gain from universal adoption of stunning before salmon slaughter is significant: eliminating several minutes of acute distress from billions of salmon annually. Economic incentives for quality improvement and consumer pressure through certification schemes are both driving adoption.