The pre-slaughter period for farmed salmon involves crowding, pumping, and handling stress that can be significantly reduced with better management and stunning protocols.
Farmed salmon pre-slaughter welfare is a domain where welfare and commercial interests are relatively well aligned: stressed fish at slaughter have inferior meat quality, so reducing pre-slaughter stress benefits both welfare and product. Despite this alignment, uptake of best-practice stunning technologies has been uneven. Fish that experience crowding, pumping, and carbon dioxide exposure before slaughter undergo prolonged stress that constitutes genuine suffering — elevated cortisol, exhaustion, and physical injury are all documented outcomes. The commercial in-water electrical stunning systems that render salmon unconscious before pump harvesting exist and are in commercial use; the barrier to universal adoption is primarily cost and infrastructure. Retailer requirements and consumer certification expectations are more effective drivers of change than voluntary industry initiatives alone.