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CaribouThe Caribou (Rangifer tarandus) is an Arctic and Subarctic deer. Around one million Caribou inhabit Alaska, and a similar amount of Caribou is found in Canada. In Eurasia, there exists an estimated number of 5 million reindeer. Outside North America, it is more commonly known as reindeer. Caribou / reindeer are found in Norway, Iceland, Sweden, Finland, northern Russia (including Novaya Zemlya), on the island of Spitsbergen, on Greenland, in Canada and in the Alaskan part of the United States. The Caribou used to inhabit Scotland, but became extinct during the 10th century A.D. In 1952, the Caribou was re-introduced to Scotland and today you can find Britain's only Caribou herd in the Cairngorm Mountains in Scotland. In Europe and Asiatic Russia, the Caribou is usually domesticated or semi-domesticated. In North America, wild Caribou populations are much more common. Sometimes the name Caribou is therefore used for wild Rangifer tarandus, while the term Reindeer is used for the domesticated variant. This is however not a strict rule. |
The Caribou is a ruminant, which means that it use a four-chambered stomach to digest its food. During the winter, the Caribou feeds chiefly on lichens, especially the extremely cold-hardy reindeer lichen (Cladonia rangiferina). This lichen is also known as Reindeer moss and Caribou moss. The Caribou will also eat the leaves of cold tolerant tree species, such as birches and willows, and grass and sedges when they are in season. Many people do not know that the Caribou is not a strict herbivore. It likes to supplement its diet with meaty items when possible, and wild Caribou will for instance eat lemmings, birds, bird eggs and voles (a small rodent).
The Caribou is well adapted to a life in cold environments, and their hooves will for instance change to fit the season. During the winter season, the hooves are small and tight. The rim of the hoof will be exposed and prevent the Caribou from slipping by cutting into the ice. During the summer season, the tundra becomes wet and soft and the hooves of the Caribou will therefore expand and turn spongy to provide better traction.
Another adaptation to the cold winter season can be seen in the nose of the Caribou. The specialized nasal turbinate bones give each nostril a huge surface area inside the nose. When the Caribou breathes, the air is heated inside the nose before it is allowed into the lungs. Water is also condensed from the used air and caught inside the body of the Caribou before the air is exhaled. The water is then used to moisten the new, incoming dry air.
The coat of the Caribou keeps the animal warm even in harsh conditions and efficiently prevents excessive heat loss. The Caribou coat consists of two layers of fur. The undercoat is dense and woolly and covered by an overcoat with longer hairs. These long hairs are hollow and filled with isolating air. These air filled hairs actually make the Caribou so buoyant that it will always keep a third of its body above the water’s surface when swimming. The Caribou is a capable swimmer that can cross big lakes as well as powerful rivers. This is useful since the Caribou is a migratory animal that can travel up to 3,000 miles (approximately 4,800 kilometers) each year. Each year, huge Caribou herds migrate from their birthing habitat to the region in which they will spend the cold winter season. When running, the Caribou can reach a speed of nearly 50 mph (80 km/h).
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Caribou