Caribou are a member of the deer family and are adapted to cope with harsh winter conditions. Their large, concave hooves allow them to travel in deep snow conditions. Today, the woodland caribou is one of the most critically endangered mammals in the U.S., with only a few woodland caribou found south of the Canada border each year.
© Jon Nickles / USFWS
They primarily eat ground and tree lichens. It takes 80 to 150 years for a forest to grow enough lichens for caribou.
There are seven subspecies of caribou, totaling approximately 5 million individuals. Two subspecies have already been driven to extinction. Today caribou can be found in parts of North America, Russia and Scandinavia. In the United States, two subspecies can be found. Rangifer tarandus granti or barren ground caribou, more well-known due to their long-distance migrations, total 950,000 and occur throughout Alaska and northern Canada.
There are two ecotypes within the Rangifer tarandus caribou, or woodland caribou, subspecies: mountain woodland caribou and northern woodland caribou. This distinction is based largely on habitat use and behavior. Woodland caribou have been reduced to one tiny population in the U.S., in far northern Idaho and northeastern Washington. This population, known as the International Selkirk population, is extremely rare, with only about 40 individuals left. These last caribou in the continental U.S. are a type of woodland caribou known as mountain caribou because they migrate to high alpine peaks in the winter. The worldwide population of mountain caribou has plummeted recently to fewer than 2000, in small, isolated populations at severe risk of elimination.
Did You Know?
Caribou are the only deer species in which both sexes grow antlers. Every year they shed their antlers and the next year they grow new ones!
Historically, woodland caribou inhabited the forests of the Northern United States from Maine to Washington State, but have been reduced to one small herd in the Selkirk Mountains of northern Idaho, eastern Washington and southern British Columbia. This last U.S. herd is reduced to approximately 40 members that tend to stay mostly in the Canadian part of its range.
Worldwide, mountain caribou are found only in northern Washington and Idaho and British Columbia. The northern ecotype of woodland caribou have a broader distribution in Canada.
Caribou are well-known for their ability to use tree growing (arboreal) lichens as a major food source. As a result they are most often associated with mature coniferous forests that provide substantial quantities of tree lichens.
Mating Season: Early to mid-October
Gestation: October to early June
Number of offspring: 1 calf