Reindeer (Rangifer tarandus)

MammalArcticDeer

Overview

The reindeer (Rangifer tarandus) — called caribou in North America — is a deer of the Arctic and subarctic. It is the only deer species in which both males and females normally grow antlers, and one of very few large mammals that thrives year-round in the far north.

Reindeer are built for cold: a dense two-layer coat, a compact body, and broad, splayed hooves that work as snowshoes on soft ground and as paddles when swimming. The hooves also change with the seasons, becoming harder in winter for digging through snow.

Conservation note: reindeer and caribou are a single species split into several subspecies and populations, and those populations differ widely in trend and status. Verify current assessments at the IUCN Red List rather than treating the species as a single case.

Habitat & Range

Reindeer occupy Arctic tundra, boreal forest and mountain habitats across northern Europe, Siberia, Alaska, Canada and Greenland. Some populations undertake long seasonal migrations between calving grounds and wintering areas; others, particularly forest and island populations, are far more sedentary.

Diet

Reindeer are herbivores. In summer they eat a broad mix of grasses, sedges, herbs, and the leaves of willow and birch. In winter they depend heavily on lichens — especially the mat-forming 'reindeer lichen' — which they reach by digging through snow with their hooves, a behaviour known as cratering.

Behavior

Reindeer are gregarious and often form large herds, which in migratory populations can be enormous. Antlers are grown and shed annually, and the timing differs by sex: males typically shed after the autumn rut, while females often keep theirs through winter — an advantage when competing for feeding craters in the snow. Reindeer are strong swimmers and readily cross rivers and lake narrows on migration.

Human Interaction & Conservation

Reindeer have one of the longest relationships with people of any northern mammal. They are herded and semi-domesticated across Fennoscandia and Siberia — by Sámi, Nenets and other peoples — for meat, hides, milk and transport, while wild caribou remain central to subsistence in North America. Pressures include habitat fragmentation from roads and industry, changing snow and icing conditions, and disturbance on calving grounds. Status varies sharply by population; consult the IUCN Red List.