Use of habitat
Wild reindeer are often referred to as the nomads of the mountains. The term nomad is usually used about communities of people who are constantly on the move, but the term is also used to describe the way in which wild reindeer use their habitat.
‘Safety in numbers’
The wild reindeer’s use of habitat is very different from that of other members of the deer family. Moose, red deer and roe deer live in the forest and rarely form large herds. Wild reindeer, on the other hand, live mainly in herds in the mountains. The size of a herd can vary from ten to several hundred animals. It is assumed that the wild reindeer herd structure is a result of cohabitation with predators. We see the same in other species, such as the gnu on the African savannah. The more animals there are in a herd, the less chance there is of being killed by a predator.
Bull groups and cow/calf groups
Wild reindeer in Norway generally live in two types of group. Bull groups are smallish groups ranging from just a few animals to roughly a hundred, and are mainly made up of bulls of different ages. The cow/calf groups can contain up to several hundred animals and mainly comprise calves, cows and young animals.
The bull groups and cow/calf groups often join forces in autumn and live together until the mating season is over. The bulls then lose their antlers and status and withdraw once more into their own group. The bulls use the outer parts of their area, while the females and calves use the central parts. This is most apparent in spring, when female reindeer often choose to return to their established calving areas, often far into the mountains. Here in the broken terrain, each female reindeer can find a safe place to calve. They are relatively safe from predators and they are also left in peace with their calves.
In spring, the groups of bulls choose a completely different strategy. They head for the outer areas where the first fertile and nutritional spring grazing grounds are to be found. This means that bulls are often observed far into the forest, often close to houses and roads. Many people are surprised to see wild reindeer so close to houses and roads, but we must remember that bull groups have a completely different threshold for interference than the more reclusive cow/calf groups.
Need a lot of space
A herd of several hundred wild reindeer requires a lot of food. The marginal and unstable existence in the mountains means that wild reindeer must roam across large areas. Climate, vegetation and geographical factors determine where wild reindeer will find food in the different seasons. In the large wild reindeer areas in Norway, we see that summer and winter grazing grounds are in very diverse areas with respect to the amount of snow and access to food. Winter grazing grounds are often areas with little snow and a good supply of lichen, while spring and summer grazing grounds are areas where the snow melts early and there is good access to fertile grazing. We can thus conclude that wild reindeer need to have large, continuous mountain areas if they are to be ensured good conditions for survival in the future