Deep-sea fishing for species like Patagonian toothfish raises welfare concerns around barotrauma, bycatch suffering, and the welfare implications of hauling fish from extreme depths.
Deep-sea fishing raises welfare concerns that are distinct from surface fisheries. Barotrauma from rapid pressure change causes internal organ damage, gas emboli, and loss of buoyancy control - causing significant distress and often death in fish that cannot be returned alive. Bycatch species including sharks, rays, and non-target fish experience the same injuries. Seabird bycatch on longlines is a major welfare concern for albatrosses and petrels. Mitigation measures including weighted lines, night setting, and tori lines reduce seabird bycatch. Consumer choice of MSC-certified products from better-managed fisheries provides market incentives for welfare improvement.