Salmon Farming Closed Containment Welfare Benefits

How recirculating aquaculture systems (RAS) for salmon provide better welfare conditions than open sea net pens.

Key Facts

Recirculating aquaculture systems (RAS) keep salmon in land-based tanks with water cleaned and recirculated internally
RAS eliminates sea lice infestation because parasites cannot complete their life cycle in enclosed freshwater-managed systems
Water temperature, oxygen and ammonia can be precisely controlled in RAS compared to the variable conditions of open sea net pens
Fish density in well-managed RAS can be lower than net pen equivalents due to better water quality management
Slaughter in RAS requires transport to processing plants - on-site slaughter would further improve the welfare chain
RAS salmon command premium prices in markets that recognise their welfare and environmental advantages

Welfare Considerations

RAS salmon welfare represents the most complete resolution currently available to the welfare challenges of open net pen farming. The elimination of sea lice infestation removes the leading cause of chronic welfare harm in conventional salmon farming; precise water quality management eliminates the environmental variability that causes welfare stress in net pen systems; and the physical security of enclosed systems eliminates the risk of escape-related welfare harms. The welfare improvements are substantial and commercially demonstrated - RAS salmon are produced to high welfare standards and achieve premium market positioning that makes the significant capital investment commercially viable. The primary welfare gap remaining in RAS is slaughter - on-site processing would eliminate transport welfare costs.

What You Can Do

Choose RAS or land-based closed-containment salmon when available as the highest welfare farmed salmon option
Support retailers and food service providers that stock RAS salmon and ask for it to be offered where not currently available
Advocate for public funding for RAS transition in salmon farming as a simultaneous welfare and environmental investment
Support development of on-site RAS processing facilities that would eliminate the transport welfare cost from the RAS advantage
Engage with salmon farmers considering RAS transition to provide market confidence that welfare premiums are commercially sustainable
Follow the work of Mowi and other major producers developing RAS capacity as industry standard rather than niche production