The 160,000 animals that make up the Porcupine Caribou Herd range throughout the Northern Yukon and neighbouring Alaska and Northwest Territories.

They cross rivers and traverse snow-covered forests and mountains. They forage on fresh spring foliage at calving-time and snow-covered lichens in winter. In summer they seek cool, windswept areas to escape insects.

Caribou adapt their behaviour and their movements to accommodate the changing seasons and year-to-year variations in climate.