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Reindeer or Caribou Rangifer tarandus
Physical Description The Reindeer lives in the cold tundra of the far north, and is well adapted to this habitat. It is a medium to large species of deer. Like many of the animals living in cold climates its outermost extremities are reduced in size. The ears and tail are small to prevent excessive loss of heat. The body is solid and muscular but the legs are short, giving it a stocky compact appearance. The coat is extremely thick, and offers excellent insulation. The coat is mostly short, but around the head and neck is longer forming a distinct mane of hairs. The coat ranges in colour from a pale creamy colour, through to a darker brown. Normally the under parts are lighter in colour than the upperparts. The coat is lighter in colour during the winter and darker during the summer months. The head is mostly white except for the muzzle which is usually brown in colour. Male reindeer tend to be larger than the females, but reindeer size can vary considerably depending on the location. Reindeer found further south tend to be larger than more northerly living animals. Reindeer possess a number of special adaptations to the cold climate. For example male Reindeer develop a thick layer of fat beneath the skin that helps store energy and provides insulation. The fur of the feet is especially long, acting like treads, thus helping it to have a firm grip on slippy and icy surfaces. The feet themselves are very broad, allowing the reindeer to move quickly over snow without sinking in. The Reindeer is the only species of deer in which the females carry antlers as well as the males. This is thought to be because females can use the antlers to find food. In snow the antlers are used to scrape snow away from the ground thus allowing the Reindeer to eat. Female Reindeer may also use the antlers to help defend the young from predators. Generally speaking the antlers of the females are not as stocky as those of the males. The size and shape of the antlers can vary considerably between animals. Usually the antlers grow in a long curving arc, first backwards but then curving back to point to the front again. The antlers can have various numbers of tines. At the end of the antlers may be a short part that is flattened into a short blade. The antlers are lost each year and regrown afresh. Females lose their antlers in spring after the young have been born. Males lose their antlers after the rut has finished in late autumn. After the antlers have been lost a new set begins to grow immediately and are normally ready by the following autumn. There
are several subspecies of Reindeer. 3 subspecies are found in
Europe, and 4 in the Americas. In the Americas this animal is
known as the Caribou, while in Europe it is called the Reindeer.
Some authors use the term Caribou to refer to all wild living
animals, and the name Reindeer to refer to those animals that
are semi domesticated.
Lifespan The maximum lifespan of wild living Reindeer is between 10 and 15 years, however few animals reach this age, and the average maximum age for Reindeer is about 4 years. Predation, insects and the climate are the main factors causing early mortality. Diet Reindeer have a hard life finding enough food to survive. They choose the best and richest plants so that they can obtain enough energy. In the winter months Reindeer are famous for feeding on lichens, and during the winter they will scrape snow away from these so they can feed. They are well known for feeding on one type of lichen, which is known as the Reindeer Lichen Cladina rangiferina. In the summer the diet is much more varied and they will feed on a variety of grasses and herbaceous plants. Breeding In Reindeer the rutting period takes place between September and October depending on the location. In any one place the rut only last a few days, and the exact timing of this depends on the latitude at which the reindeer live. Mating is very competitive; males try to collect together a small number of females, which they can then mate with as they come into season. Other males will try to fight other males for the possession of these small groups. Fighting may occur with the males locking their antlers and trying to push each other away. Usually the most dominant male wins these contests and obtains possession of the females. Successful males may be able to collect together as many as 20 females. The gestation period is 210 to 240 days long. Normally only a single calf is born. Most of the young are born in June. At birth the calves weigh 5 kg. The calves are able to walk within an hour of birth. They have to become mobile quickly because of the danger of predators such as wolves or bears. Growth occurs quickly, with the young reaching 35 kg by October. The mother's milk is especially rich and high in fats. The young are suckled by their mothers for 4 to 5 months, but start to eat green matter from only a few weeks of age. Sexual maturity is reached from 2 years of age. Behaviour The Caribou of North America are famous for their long migrations. At the beginning of spring they form into large herds that can number into the tens of thousands. These herds move slowly northwards towards the traditional calving grounds and away from the boreal forests. After the calves are born the Caribou continue northwards to new feeding grounds on the tundra where they spread out and spend the summer. As autumn approaches they begin to collect together into herds again and move southwards again to find shelter from the harsh winter weather. When they reach the forests they disperse and try to find shelter and food beneath the trees. Two main things cause this migrationary behaviour. Firstly during the summer months the tundra area becomes alive, and is an excellent resource of food for the Reindeer. By moving northwards the Caribou can take advantage of all this food that no other animals can use. Another factor causing them to move northwards are the numerous airborne parasites that attack the Caribou. As spring starts these begin to hatch out and attack the Caribou. Insects like midges will bite Caribou and try to suck their blood, this can cause the Caribou to lose a large amount of blood and weaken the animals considerably. Other insects may lay there eggs on Caribou and when these hatch out into maggots they eat into the Caribou causing injury and death. To avoid these attacks Caribou move northwards where it is cooler. On the open plains there is more wind that helps to blow insects away. However, not all Caribou migrate, many populations are sedentary and remain in the same place all year around. The most famous migrations occur in Alaska and Canada. Reindeer is northern Europe and Asia are less migrationary in behaviour. The Sami
people of Northern Europe have semi-domesticated the Reindeer
herds of northern Scandinavia. The herds of Reindeer are still
free to roam where they like, but they are followed by the Sami
people. Each family owns a herd of reindeer, which they hunt for
meat and skins, and even milk. The Sami people are one of the
few remaining nomadic people remaining in the wild, having to
follow their reindeer wherever they decide to go.
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