Recirculating Aquaculture Systems and Fish Welfare

Land-based recirculating aquaculture systems offer improved welfare control compared to open-net cage farming, eliminating sea lice and providing managed water quality.

Key Facts

Recirculating Aquaculture Systems (RAS) reuse 95-99% of water, dramatically reducing environmental footprint
RAS eliminates sea lice infestations that plague open-net cage salmon farming
Water quality parameters including oxygen, temperature and pH can be precisely controlled in RAS
Capital and energy costs of RAS are significantly higher than open-net cage systems, creating economic barriers
Several large-scale RAS salmon farms are now operational in the UK, US and Norway

Welfare Considerations

Recirculating Aquaculture Systems represent the most promising pathway to high-volume fish production with genuinely improved welfare. The elimination of sea lice — one of the most significant welfare problems in open-net salmon farming — is achievable only through closed containment. Water quality control allows management of the oxygen, temperature and pH parameters that determine fish stress and health. The environmental benefits of eliminating discharge to wild fish populations add conservation co-benefits. The economic barriers are real — capital intensity and energy costs are substantially higher — but falling costs and growing premium markets for sustainably and humanely produced fish are creating commercial viability.

What You Can Do

Choose salmon and other farmed fish from land-based RAS facilities where available
Support investment in RAS technology development by choosing premium welfare-certified products
Advocate for regulatory frameworks that incentivize RAS over open-net cage expansion
Donate to organizations researching and promoting land-based aquaculture as a welfare improvement