Aquaculture

Farmed Salmon Crowding Stress Advanced Welfare

Crowding at high stocking densities is one of the most significant chronic stressors for farmed Atlantic salmon. The welfare impacts are broad, affecting immunity, feeding and behaviour.

Key Facts

High stocking densities above 25 kg per cubic metre significantly increase cortisol
Crowding reduces feeding behaviour, activity and increases aggression markers
Norwegian industry targets 20-25 kg per cubic metre but some operations exceed these
Operational crowding during treatments creates acute welfare events distinct from chronic density

Welfare Considerations

Salmon crowding welfare requires both chronic stocking density management and acute event minimisation during treatments, harvests and transfers. Monitoring behavioural indicators at the surface alongside physiological measures provides complementary welfare assessment.

What You Can Do

Choose salmon from producers publishing stocking density welfare data
Support RSPCA Assured and equivalent salmon welfare standards with density limits
Advocate for stocking density transparency in aquaculture welfare reporting