Seabirds face multiple anthropogenic welfare threats including plastic ingestion, bycatch in fishing gear and food web disruption from overfishing.
Plastic ingestion causes intestinal blockage, chemical toxicity and malnutrition as birds feed plastic to chicks who cannot expel it. Bycatch in longlines causes drowning of air-breathing birds that are aerobically fit and terrified of submersion. Forage fish overfishing forces adult seabirds to make repeated unsuccessful foraging trips before returning to starving chicks — welfare harm extended across the entire colony. Mitigation measures including bird-scaring lines, setting at night and steel leaders are effective but unevenly adopted.