Diet & Food 

The great differences in the weather conditions between the seasons have an effect on the availability of forage for reindeer. In summer, a reindeer must maximize its food intake and in winter, it has to manage on scanty nutrition. Due to its physiology and characteristic behaviour, the reindeer has adapted to these great changes. It has a seasonal rhythm which governs its reproduction and growth, and its need for nutrition increases with the onset of spring and in early summer. In winter, as food becomes scarce, the reindeer lives sparingly on so-called rationing. At this time, its need for nutrition and its appetite decrease.

As a member of the moose family, the reindeer is a ruminant with four stomachs. It is a selective grazer but is able if necessary to live on a simpler diet of hay. However, it does prefer to eat the easily digestible parts of plants that are rich in nutrients.

Due to the increasing numbers of microorganisms in its front stomachs, it is also able to digest and effectively utilize parts of plants that are harder to break down. The problem with the reindeer is its poor ability to adapt to rapid changes in nutrition and periods of starvation. The activities of micro-organisms in the stomachs need time to adapt to new foods. In winter, as food runs out, the activity of the microorganisms in the reindeer's paunch may also cease, which may result in its death. Even if food were available, it could be difficult to get the digestive system to start up again after the period of starvation.

The reindeer grazes in different areas according to the seasons. In spring, as nature turns green, it starts to eat the fresh, green parts of plants. Important plants include wavy hair-grass, cotton grass, tufted hair-grass, sheep's fescue and several types of sedge. It also eats several dwarf shrubs, lichens and tasty leaf buds from trees and bushes and it digs up highly nutritious sedge rootstocks as soon as the marshes start to thaw.

In early summer, the reindeer roams in areas where plant growth starts earliest such as in wetlands, birch forests and marshes. In terms of nutritional value, the grazing grounds of early summer are the best the year has to offer the reindeer. Young grass shoots in particular have high protein content, which is important for the reindeer to grow, gain strength and produce milk. Other important plants at this time of year include buckbean and marsh cinquefoil rootstocks, and willow and birch leaves.

In summer, the reindeer roams over the open fells, marshes, clear-felled areas, along stream banks, and in natural meadows. The reindeer finds plants that are in a continual stage of early growth up on the high fells. In particular, several grasses and hydrophytes are important sources of nutrition for the reindeer - its favourites include angelica, rosebay, wood crane's-bill and common cow-wheat. The reindeer also loves to eat water horsetail. As summer nears its end, the protein content and nutritional value of plants decreases and they start to become woody and dry.

When sufficient protein is no longer available to help growth, the reindeer starts to accumulate fat in readiness for the coming winter. In the autumn, reindeer eat mushrooms in particular. It especially loves the large boletus but generally speaking, any kind of mushrooms will do. The nutritional value of mushrooms is great. The reindeer also eats hay, sedges and grasses, the nutritional values of which constantly deteriorate as autumn progresses. At this time, the reindeer starts to eat more shrubs, such as heather and blueberry.

The importance of lichen increases with the onset of winter. Lichen is vital basic forage for the reindeer in winter. Lichens contain plenty of energy needed by the reindeer partly owing to the fact that they contain easily digestible carbohydrates. However, their protein content is low. In addition to lichen, important sources of nutrition for the reindeer include different shrubs as well as the parts of hay and grasses that stay green in winter, which the reindeer digs out from under the snow.
    

Source courtesy of: http://www.paliskunnat.fi/default.aspx?kieli=en-US