California halibut is a developing aquaculture species on the US Pacific coast with welfare challenges specific to its flatfish biology and transition from wild-caught to farmed production.
California halibut share welfare challenges with other flatfish in aquaculture: denial of natural substrate-settling behaviour, exposure to bright uniform lighting, and territorial aggression at high densities. The developmental metamorphosis period is a welfare-sensitive time with high mortality in poor conditions. Industry development is outpacing welfare standard development, creating a window for establishing welfare norms before bad practices become entrenched.