Atlantic halibut (Hippoglossus hippoglossus) is the world's largest flatfish and an emerging aquaculture species of increasing commercial importance, particularly in Norway and Iceland. As production expands, understanding and addressing the specific welfare needs of this species is crucial.
Halibut are flatfish that spend most of their adult life lying on the sea floor, using camouflage to ambush prey. They have complex sensory capabilities, including well-developed eyes that can move independently, and respond strongly to environmental conditions. Their natural behaviour includes extended periods of inactivity interspersed with prey capture activity.
Halibut aquaculture faces several specific welfare challenges:
Halibut grow to large sizes (market weight 2-5 kg in aquaculture, up to 300 kg in the wild) requiring careful handling. Stress during handling causes cortisol release and welfare compromise. Appropriate electrical stunning before slaughter is important for welfare; halibut require different parameters than salmon or trout due to their morphology and size.
Halibut are susceptible to bacterial infections including pasteurellosis and vibriosis. Vaccination programs are available. Treating disease promptly and providing appropriate pain management during handling and interventions is a welfare priority in a species where welfare consciousness is still developing.
Wild-caught Atlantic halibut is subject to severe quotas due to stock depletion from overfishing. Aquaculture offers relief of fishing pressure on wild populations — a conservation welfare benefit. However, aquaculture production must itself meet high welfare standards to represent a genuinely more ethical alternative to wild capture.