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Moose



The moose (Alces alces), also known as elk in Europe, is a horse-sized, northern species of deer that occurs in the boreal and north-temperate forests of both North America and Eurasia. At one time, the Eurasian and American moose were considered to be separate species, but these animals are fully interfertile and are now thought to be the same species. However, there are many geographically distinct subspecies of these animals.



Like other deer (family Cervidae), moose have cloven hooves, and are therefore in the mammalian order Artiodactyla. Moose are the largest animals in the deer family, weighing as much as 1,750 lb (800 kg) and standing as tall as about 6.6 ft (2 m). The largest moose occur in Alaska (Alces alces gigas). Moose are unusuallooking animals, with a long and large head, long legs, a short neck and tail, and a hump over their shoulders, which are taller than their hips. Moose convey a superficial appearance of ungainliness, but they can run swiftly and skillfully over difficult, uneven, and wet terrain. Moose are also good swimmers.

Moose are ruminants, meaning their stomach is divided into four discrete chambers, which are concerned with particular, sequential aspects of digestion of the fibrous plant biomass these animals feed upon. Moose ruminate, meaning they regurgitate and rechew forage that has spent some time fermenting in one of the fore-chambers of the stomach.

Moose have large, shovel-shaped antlers, which are bony outgrowths of the frontal bones of their skull, a characteristic shared with other species in the deer family. The antlers of moose only develop on male animals. The antlers of the oldest, strongest males are especially large and wide (up to 6.6 ft [2m]), and they have intricate outgrowths known as tines on their edge, which can number as many as forty. The antlers of moose are deciduous, meaning they are grown during the springtime and summer, A moose feeding on pond vegetation in Baxter State Park, Maine. Photograph by Robert Essel. Stock Market. Reproduced by permission. for use in jousting with other males for access to females during the rutting season, and are later shed in the late autumn or early winter. While the antlers are growing, they are covered with densely vascularized tissue known as velvet, which dries once the antler growth is complete by the late summer. The dry velvet is removed by rubbing against trees and other solid objects, leaving only the bare antler bone exposed. Male moose also have a large dewlap hanging under their neck, sometimes called a bell.

During the autumn rutting season, fights between evenly matched bull moose can be dramatic contests, and can lead to death for one of the combatants. Rarely, two bulls will lock their horns together so tightly that it causes the death of both animals. Bull moose are extremely aggressive during their rut, and at this time they are dangerous to humans.

Moose calves are born one or two at a time, and they are precocious, meaning they are capable of standing and moving about with their mother soon after birth. The calves nurse for up to a year, and moose can live for as many as 25 years. Moose are not very social animals, mostly coming together only for the purposes of breeding. In some regions with deep snow in the winter, moose may aggregate in dense stands of conifer trees, known as yards.

Moose feed on a wide variety of plants, and their diet varies seasonally. Most of the year moose feed by browsing on young shoots and foliage of woody shrubs and short trees. During the summer these animals prefer to eat herbaceous vegetation, including aquatic plants, which they seek while standing in the water, often feeding beneath the surface. At these times, individual moose can be approached rather closely (and carefully) by canoe, and can be taken totally by wide-eyed surprise when they lift their heads above water again, subsequently running away with enormous splashes.

The upper lip of the moose is unusually large and prehensile, and is adapted to feeding on woody plants. The long legs of moose make it easy for them to feed relatively easily in the canopy of shrubs and trees. However, this trait, in combination with their short neck, makes it difficult for these animals to feed on lower-growing, herbaceous vegetation. Therefore, when grazing on grasses and forbs, moose often must kneel rather awkwardly. Moose diets are generally low in sodium, and these animals therefore crave salt. As a result, moose (and other deer) are sometimes seen along roadsides, eating vegetation that is relatively rich in sodium because of the use of road salt in winter.

Moose are hunted throughout their range, both for sport and as a source of wild meat and tough hides. Until rather recently, moose were overhunted throughout much of their range, and their populations were reduced to low levels. Now, however, the hunting of most moose populations is regulated, and their abundance is somewhat higher.

In some regions of eastern North America, whitetailed deer (Odocoileus virginianus) have become quite abundant. This has largely happened because of human activities that create favorable habitat for the whitetailed deer, such as some types of forestry and the abandonment of agricultural lands. If moose also occur in places where white-tailed deer are abundant, they may suffer from a debilitating nematode parasite known as brainworm (Parelaphostrongylus tenuis). The deer population is resistant to this parasite, but the brainworm is abundant where the deer are common, and the moose population consequently suffers.


Resources

Books

Banfield, A.W.F. The Mammals of Canada. Toronto: University of Toronto Press, 1974.

Grzimek, B., ed. Grzimek's Encyclopedia of Mammals. London: McGraw Hill, 1990.

Runtz, M.W.P. Moose Country. Saga of the Woodland Moose. Minocqua, WI: Northword Books, 1992.

Wilson, D.E., and D. Reeder, compilers. Mammal Species of the World. 2nd ed. Washington, DC: Smithsonian Institution Press, 1993.


Bill Freedman

KEY TERMS

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Browse

—A food consisting of the foliage, twigs, and flowers of woody plants.

Ruminant

—A cud-chewing animal with a four-chambered stomach and even-toed hooves.

Rutting season

—A period of sexual excitement in an animal, for example, in bull moose during the autumn.

Yard

—A wintertime, forested habitat of certain species of deer, generally dominated by coniferous trees and having a relatively shallow accumulation of snow.

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