Farmed Salmon Pre-Slaughter Welfare

Welfare challenges during the pre-slaughter period for farmed Atlantic salmon and the evidence supporting improved stunning and handling practices.

Key Facts

Atlantic salmon is the most valuable farmed fish globally, with annual production exceeding 2.7 million tonnes
Pre-slaughter handling including crowding, net lifting, and out-of-water exposure causes acute stress measurable by cortisol and blood glucose levels
Percussion stunning followed by spiking (ikejime) and exsanguination achieves rapid insensibility and death when properly executed
Electrical stunning in water is increasingly adopted and can render fish insensible within milliseconds when parameters are correct
CO2 narcosis, previously common, causes visible distress before insensibility and is now considered inhumane by welfare scientists
The Humane Slaughter Association and RSPCA have published salmon welfare slaughter guidance that is increasingly adopted in UK and Norwegian industries

Welfare Considerations

Pre-slaughter welfare for farmed salmon has received growing attention as scientific understanding of fish pain capacity has advanced. The period from crowding in harvest pens through to slaughter involves multiple stressors that cause measurable physiological distress. Welfare-positive practices include pre-harvest fasting of appropriate duration to reduce gut content without excessive starvation, minimizing crowding and out-of-water time, effective pre-slaughter stunning, and rapid death following stunning. The industry has the technical knowledge and tools to dramatically reduce pre-slaughter suffering — the barriers are primarily economic and regulatory. Consumer demand for certified welfare-conscious salmon and regulatory requirements for effective stunning are the most powerful drivers of change.

What You Can Do

Choose farmed salmon certified by schemes that include pre-slaughter welfare requirements such as RSPCA Assured
Ask retailers about their salmon supplier welfare standards, specifically regarding slaughter methods
Reduce farmed salmon consumption or shift to alternative protein sources with lower welfare footprints
Support research into improved salmon welfare indicators and stunning efficacy monitoring in commercial settings
Advocate for regulatory requirements mandating effective stunning for all farmed fish before slaughter