Longline fishing for tuna captures fish alongside significant bycatch species, raising welfare concerns for both target species and non-target animals.
Longline fishing welfare concerns extend to both target and non-target species. Tuna captured on longlines may experience prolonged exhaustion, stress, and injury before retrieval. Bycatch species including sea turtles and sharks suffer injury and death. Seabirds particularly petrels and albatrosses are killed when they dive for baited hooks. Bird-scaring lines and night setting reduce seabird bycatch substantially. Circle hooks and fish bait instead of squid reduce sea turtle bycatch. Time-on-hook welfare for target tuna is difficult to address in open ocean fisheries but rapid haul-in protocols reduce duration. Observer coverage and electronic monitoring improve bycatch documentation and accountability.