Fish

Recirculating Aquaculture Systems: Higher Welfare Fish Farming

Land-based recirculating aquaculture systems can produce fish with dramatically better welfare than open-cage sea farming.

Key Facts

Recirculating aquaculture systems (RAS) control water quality, temperature, and oxygen precisely
RAS facilities can maintain sea lice-free conditions eliminating one major welfare problem
Closed systems prevent escape of farmed fish into wild populations
Mortality rates in RAS salmon farms can be below 3% vs 15-20% in sea cage operations
Energy use and capital costs for RAS are higher than sea cage farming but falling

Welfare Considerations

RAS facilities represent a significant welfare improvement over open-cage aquaculture for salmon and other species. Precise control of water chemistry eliminates hypoxia and ammonia stress. Sea lice are absent, eliminating one of the most significant welfare harms in conventional salmon farming. Lower density stocking is easier to maintain. The higher capital and operating costs are barriers but technological improvement is reducing them steadily.

What You Can Do

Support RAS-produced fish products when labeled as land-based or closed-containment
Advocate for RAS expansion through investment policy and consumer preference
Donate to organizations developing higher-welfare aquaculture standards
Support research into RAS cost reduction and species expansion
Engage with your seafood retailer about sourcing higher-welfare aquaculture products