Atlantic halibut aquaculture has expanded significantly as wild stocks remain depleted. The unique biology of flatfish creates specific welfare challenges around metamorphosis, eye migration, and benthic behavior.
Halibut welfare in aquaculture is complex partly because of their unusual biology. The juvenile metamorphosis period is stressful and often lethal for a significant proportion of farmed fish. Adults require specific tank floor space to rest and settle naturally. Common welfare issues include cataracts from dietary problems, fin and skin damage from tank contact, and inadequate stun quality at slaughter. Norway, which leads Atlantic halibut aquaculture, has developed welfare guidelines that include stunning requirements. The slow growth rate makes welfare across the full production cycle particularly important from an aggregate suffering perspective.