Recirculating aquaculture systems offer potential welfare advantages over sea cage salmon farming by controlling environment, but introduce new challenges that require careful welfare assessment.
Recirculating aquaculture systems represent a significant innovation in salmon farming that can address some of the most serious welfare problems of sea cage production. Freedom from sea lice eliminates one major chronic welfare burden. Controlled water quality allows optimal oxygen, temperature, and ammonia management. However, RAS is not inherently welfare-positive — high stocking densities, water quality failures, and handling stress remain potential welfare problems. The welfare advantages of RAS must be realized through careful management and monitoring rather than assumed from the system type alone.