Recirculating aquaculture systems offer advantages for both fish welfare and environmental sustainability compared to open net pen farming when well-designed and managed.
Recirculating aquaculture systems represent one of the most significant opportunities to improve farmed fish welfare while also improving environmental sustainability. By completely separating fish from wild aquatic environments, RAS eliminates the sea lice infestations and disease transmission that cause chronic welfare problems in net pen salmon farming. The controlled environment allows precise oxygen, temperature, and water quality management that reduces chronic stress from environmental fluctuations. However, RAS is not inherently welfare-superior if management quality is poor - high density in a controlled environment can still cause welfare problems. The welfare advantage of RAS is conditional on appropriate density, excellent management, and continuous monitoring of welfare indicators.