Farmed Salmon Mortality Rates: A Key Welfare Indicator

Mortality rates in salmon aquaculture are a critical welfare indicator, with industry averages masking significant variation between operations.

Key Facts

Average mortality in Atlantic salmon farming ranges from 10-20% over the full production cycle
Sea lice, gill disease, and amoebic gill disease are the leading mortality causes
Norwegian regulations require reporting and action when mortality exceeds certain thresholds
High mortality operations typically have multiple concurrent welfare problems
Mortality during crowding and harvest is often undercounted in reported statistics
Better-managed farms achieve mortality rates below 5% - demonstrating significant improvement potential

Welfare Considerations

Mortality rates in salmon farming serve as a proxy welfare indicator precisely because they reflect cumulative welfare failures - disease burden, stress responses, and suboptimal environmental conditions that collectively reduce survival. High mortality signals that living fish are also experiencing welfare compromise, not just that some fish died. Tracking and reporting mortality transparently creates incentives for welfare improvement, while industry averages that mask poor-performer outliers allow the worst welfare situations to persist. Welfare-conscious regulation requires operation-level reporting and meaningful action thresholds.

What You Can Do

Choose salmon certified by schemes requiring mortality rate monitoring and transparency
Ask retailers what mortality benchmarks their salmon suppliers must meet
Advocate for mandatory mortality rate reporting in aquaculture regulations
Support research into disease prevention approaches that reduce the leading mortality causes
Reduce salmon consumption or choose suppliers with verified low mortality rates
Engage with aquaculture certification bodies about mortality as a welfare standard