Halibut farming presents specialized welfare challenges linked to the species benthic lifestyle, light sensitivity, and distinctive physical adaptations.
Halibut welfare in aquaculture is complicated by the mismatch between their specialized benthic ecology and standard tank farming designs. Their need to rest on substrates, their sensitivity to light intensity and spectrum, and their large natural size relative to practical tank dimensions create inherent challenges. Pseudoalbinism — abnormal darkening of the normally pale underside — is a documented indicator of developmental stress during metamorphosis and early rearing, serving as a welfare proxy in commercial settings. Stocking density management requires careful balancing since halibut aggression during feeding causes significant injury at higher densities. Their slow growth means welfare management must be sustained across multi-year production cycles. Industry certification for halibut welfare is less developed than for salmon, leaving significant variation in welfare standards across producers.