How predator encounters affect welfare in farmed salmon and strategies for managing predator pressure in sea cage aquaculture.
Predator pressure on sea cage salmon creates both direct welfare harms through injury and indirect chronic stress through the presence of predators around cage perimeters. Even when anti-predator nets prevent successful attacks, the chronic presence of predators causes measurable stress responses in salmon. Welfare-focused predator management seeks to exclude predators humanely while minimizing noise-based deterrents that themselves cause fish stress. Improved cage design with finer netting and better structural integrity reduces predator access without acoustic deterrents.