Wild Caribou Welfare: Migration, Predation, and Climate

Caribou undertake some of the longest land migrations of any animal, facing welfare challenges from predation, insect harassment, changing snow conditions, and industrial development fragmenting their migration routes.

Key Facts

Barren-ground caribou migrate up to 4,800 km annually - the longest terrestrial migration of any land animal
Global caribou and reindeer populations have declined by 40% over the past 25 years
Summer insect harassment from biting flies and warble flies causes caribou to lose significant foraging time
Calves born during spring migration face cold, starvation, and intense predation pressure
Oil field development in Alaska's Arctic National Wildlife Refuge affects key calving grounds
Changing snow conditions from climate warming affect the ability of caribou to access vegetation under ice
Predation by wolves and bears causes significant mortality, particularly of calves in their first weeks

Welfare Considerations

Caribou face welfare challenges across every season. In summer, insect harassment is so intense that caribou abandon prime feeding areas, running in the heat and losing weight trying to escape flies and warble fly larvae that burrow under their skin. The warble fly larvae cause painful boils as they develop and migrate through tissue before emerging through holes in the skin. During migration, calves that fall behind are quickly killed by wolves or bears. Ice-crusted snow created by warming and refreezing cycles prevents caribou from reaching vegetation, causing starvation. The cumulative seasonal welfare burden on individual caribou - insects, predation, physical demands of long migration - is substantial.

What You Can Do

Support protection of the Arctic National Wildlife Refuge calving grounds from industrial development
Advocate for wildlife crossing infrastructure that allows caribou to cross roads and pipelines safely
Support Indigenous community monitoring programs that track caribou welfare and population health
Reduce your carbon footprint to slow the climate changes disrupting caribou snow conditions
Learn about the cultural and ecological importance of caribou to Arctic ecosystems and Indigenous peoples