Binghamton Zoo Animals

Reindeer

(Rangifer tarandus)
Order: Artiodactyla
Family: Cervidae
Genus: Rangifer
Species: tarandus

HABITAT AND RANGE: Reindeer inhabit arctic tundra and subarctic (boreal) forest regions in the northernmost lands around the world, including Greenland, Canada, Alaska, Scandinavia and Russia.

PHYSICAL CHARACTERISTICS: The weight of a female varies between 130 and 375 lbs. In some subspecies of reindeer, the male is slightly larger; in others, the male can weigh up to 600 lbs. Both sexes grow antlers, which for old males fall off in December, for young males in the early spring, and for females, summer. The antlers typically have two separate groups of points, a lower and upper. Domesticated animals (reindeer) are shorter-legged and heavier than their wild counterparts (caribou). The caribou of North America can run at speeds up to 50 miles per hour and may travel 3,000 miles in a year.

ADAPTATIONS: Reindeer have specialized noses featuring nasal turbinate bones that dramatically increase the surface area within the nostrils. Incoming cold air is warmed by the animal’s body heat before entering the lungs; water is condensed from the expired air and captured before the deer’s breath is exhaled, used to moisten dry incoming air and possibly absorbed into the blood through the mucous membranes. Reindeer have veins and arteries which are positioned close to the limbs, which are arranged to allow heat exchange. The cold blood returning from the limbs is warmed by the arterial blood coming from the heart. The pre-warmed blood entering the body helps to conserve energy. This “counter-current” mechanism is found in other animals including many species of waterfowl. Their large concave hooves help support Reindeer in the snow and soft tundra and are also useful when swimming. Reindeer make an audible clicking noise when walking, which is produced from tendons rubbing across a bone in the foot. Reindeer hooves adapt to the season. In the summer, when the tundra is soft and wet, the footpads become spongy and provide extra traction. In the winter, the pads shrink and tighten, exposing the rim of the hoof which cuts into the ice and crusted snow to keep the animal from slipping. The reindeer coat has two layers of fur, a dense woolly undercoat and longer-haired overcoat consisting of hollow, air-filled hairs. A caribou or reindeer swims easily and fast. Migrating herds will not hesitate to swim across a large lake or broad river.

DIET: Reindeer are primarily grazing herbivores. Their diet is most variable during the summer, when they consume the leaves of willows and birches, mushrooms, cotton grass, sedges and other ground-dwelling vegetation. Lichens are an important component of their diet throughout the winter.

REPRODUCTION AND DEVELOPMENT: Females breed at 2 years and males at 3 years. In the fall, bulls savagely fight for a harem of 5-40 cows. After a gestation period of about 240 days, one or two unspotted young are born on summer grounds. The youngsters are able to walk within 2 hours, nurse for 2 months and then join the herd in the fall migration. The life span of the Reindeer is approximately 15 years.

STATUS IN WILD: Common. Some populations of the woodland variety are in serious decline.