Canada and Alaska, Greenland, northern Europe, and northern Asia


Tundra, mountains, and woodlands

Reindeer or caribou?

Even though no one has actually seen a reindeer fly, this special member of the deer family has a lot to live up to! Reindeer and caribou are classified as the same genus and species, Rangifer tarandus. In Europe, they are called reindeer. In North America, the name reindeer is used when referring to Eurasian populations and the name caribou to refer to wild populations in North America. We also use reindeer to refer to domesticated individuals, even those in North America. For the purposes of this fact sheet, we will refer to the animals as reindeer.

From the top

Antlers are the reindeer’s most memorable characteristic. A male’s antlers can measure up to 51 inches (130 centimeters) long, and a female’s antlers can reach 20 inches (50 centimeters). Just as a tree has a trunk, so all antlers have a main beam and several branches or tines that grow from the frontal bones of the skull. Sometimes little branchlets or snags are also present. The tip of each antler is called a point. Unlike horns, antlers fall off and grow back larger every year. As new antlers grow, the reindeer is said to be in velvet, because skin, blood vessels, and soft fur cover the developing antlers. When the velvet dries up, the reindeer rubs it off against rocks or trees, revealing the hardened, bony core.

Males begin to grow antlers in February and females in May. They both finish growing their antlers at the same time but shed their antlers at different times of the year. A male drops his in November, leaving him without antlers until the following spring, while female reindeer keep their antlers through the winter until their calves are born in May. This fact has led many to believe that, based on the presence of antlers, Rudolph the red-nosed reindeer must have been a female to have those antlers on Christmas Eve!

But what are the antlers for? They are handy weapons against predators, males use their impressive antlers (which can weigh up to 33 pounds or 15 kilograms!) to woo the females, and females use theirs to clear away the snow to find food.

Both male and female reindeer grow long antlers, the only deer species to do so.
Some reindeer travel 9 to 40 miles (15 to 65 kilometers) daily in the same area; others migrate 750 miles (1,200 kilometers) twice a year in large herds.
In comparison to body size, reindeer have the largest and heaviest antlers of all living deer species.
Adult reindeer can swim 4 to 6 miles per hour (6 to 10 kilometers per hour) and can run up to 50 miles per hour (80 kilometers per hour).
When reindeer walk, their hooves make a loud clicking noise due to a tendon slipping over the foot bone.
Reindeer are the only deer species to have hair completely covering their nose.

Our first reindeer, Donder and Blitzen, arrived as calves in 1932 as a donation. Two years later, we welcomed the birth of Blitzen’s first calf. More reindeer were donated from Alaska in 1938.

Today, our small herd of reindeer is exhibited on the hillside behind the polar bear exhibit in the Northern Frontier. They are descended from Siberian reindeer.

The worldwide reindeer population, including domesticated reindeer, is about 5 million, including about 900,000 caribou in Alaska. Today, population density, predation, and disease seem to determine herd sizes of wild reindeer. Historically, overhunting has caused some reindeer populations to decline. Despite strict anti-hunting measures, poaching is still a major threat in Russia. In Finland, logging and winter sporting activities may disturb reindeer habitat. And hybridization with domesticated reindeer is a potential problem for some populations.

The Arctic is changing, and as temperatures rise, white-tailed deer move into areas occupied by reindeer. These deer carry a worm parasite that is fatal to moose and reindeer populations. Warmer summers also mean more insect activity. Reindeer that are harassed by insects may not be able to forage enough to put on the weight they need to last through winter.

People are changing the tundra, too. Expanding oil exploration, industrial development, and increased disturbance from aircraft and snowmobiles are just some examples. So far, reindeer have been able to adapt to the presence of people and machines. But as people continue to develop the Arctic, the ongoing challenge will be to consider the needs of reindeer herds.

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