Atlantic halibut aquaculture is growing as an alternative to wild capture, with welfare challenges unique to this distinctive flatfish species.
Halibut are particularly sensitive to handling stress and show physiological responses to disturbance that persist longer than many other farmed fish. Crowding during grading operations causes acute stress responses and can trigger disease outbreaks. Abnormal pigmentation in juveniles — where the underside becomes partially pigmented — is associated with stress and lighting deficiencies. Their large potential size means welfare compromises compound over long production cycles.