Atlantic halibut aquaculture has expanded significantly but faces persistent welfare challenges including eye migration, juvenile mortality, and crowding stress in this unique flatfish species.
Halibut welfare in aquaculture presents unique challenges arising from their unusual biology and life history. The metamorphosis from juvenile to adult form involves significant physiological change during which mortality is high and welfare compromise is poorly understood. Adult halibut require tank environments that accommodate their bottom-dwelling lifestyle, with appropriate substrate access, water flow management, and reduced crowding to prevent the aggression and fin damage associated with high density systems. Pre-slaughter stunning is less systematically practiced in halibut than in salmon, representing a welfare gap in an otherwise relatively high-value production sector with capacity to invest in welfare improvements. Consumer awareness of halibut welfare issues is very low, creating an advocacy opportunity.