Aquaculture

Farmed Salmon Crowding and Stress

Stocking density in salmon farming affects stress, injury, disease, and growth. Understanding the welfare implications of crowding informs better management standards.

Key Facts

Atlantic salmon in net pens show elevated cortisol at densities above 25 kg per cubic meter
Crowding increases aggression, fin damage, and cataracts in farmed salmon populations
Lower density operations have better welfare outcomes but require more water volume and infrastructure
Optimal density balances welfare with production efficiency and varies by water quality and life stage

Welfare Considerations

Crowding is one of the most fundamental welfare parameters in salmon farming. High densities impair welfare through stress, injury, and disease while also reducing feed conversion and growth efficiency. Establishing and enforcing maximum stocking density limits based on welfare evidence is one of the most practical ways to improve salmon welfare at scale across the industry.

What You Can Do

Support aquaculture certification programs with explicit maximum stocking density limits for salmon
Ask seafood suppliers about the stocking densities used by their salmon farming sources
Advocate for density regulations grounded in welfare science for salmon aquaculture
Support research establishing species-specific optimal density ranges for farmed fish welfare