Pre-slaughter crowding and handling in salmon aquaculture cause significant stress. Innovations in slaughter technology are improving welfare outcomes in the industry.
The period immediately before slaughter is often the most welfare-significant for farmed salmon. Crowding concentrates fish at extreme densities, triggering acute stress responses including cortisol surges, mucus loss and scale shedding. Without effective stunning, slaughter methods including CO2 immersion cause prolonged suffering before insensibility. Industry investment in high-throughput percussive and electrical stunning systems has improved welfare in leading operations. Consumer demand for welfare-certified salmon provides commercial incentive for investment in humane slaughter.