UBC Theses and Dissertations
A study of the muskox (Ovibos moschatus) in relation to its environment Tener, John Simpson
A study of the muskox (Ovlbos moschatus) in relation to its environment was carried out in the Canadian Arctic between 1952 and 1959. Environmental factors such as climate, soils and summer and winter range vegetation were examined. The numbers, distribution, population structure, behaviour and general biology of muskoxen were studied. Muskoxen live in an Arctic environment of short cool summers, long, cold winters and relatively little snow. Range studies at the southern and northern limits of muskox distribution in Canada revealed major differences in plant species occurrence, annual production and chemical values. The summer ranges in the Thelon Game Sanctuary produced more woody food species than Lake Hazen ranges and were calculated to support as many as seven times the number of muskoxen. Thelon winter ranges may support up to ten times as many muskoxen as Lake Hazen winter ranges of comparable size. Total annual forage production in the Thelon compares favourably with forage production on mountain sheep and elk ranges in Jasper and Banff National Parks. Summer and winter food habits of the species were determined. Chemical analyses of the important foods revealed that adequate amounts of protein, carbohydrates, calcium and phosphorous, with perhaps less fat than desirable were available to muskoxen on Thelon summer ranges. Thelon winter range foods contain less phosphorous than recommended for range cattle, which conceivably could interfere with reproductive performance. Lake Hazen summer and winter range foods appeared to be nutritionally adequate although low forage production may affect population growth adversely. Muskoxen are slowly increasing in most areas in the Arctic where they occur. Studies of age structure in herds indicate that calf production is low by most ungulate standards. The muskox exhibits a number of adaptations to Arctic living. Its short limbs, dense inner and outer hair and its generally slow movements contribute to heat conservation. As a ruminant, the muskox synthesizes Vitamin B and proteins. Food probably is stored in summer in the liver for winter use. Lactation is prolonged, up to 15 months at least, which would assist calf survival during winter. The ungulate eye permits feeding during winter darkness. Muskoxen are cosmopolitan feeders, essential in areas such as the Arctic where plant growth is sparse. Feeding is not intensive in an area, as herds are widely scattered and move frequently. The relatively late age of sexual maturity in cows and. bulls reported for wild living individuals, the low percentage of calves in populations studied, the production of calves biennially, the generally low production of food in Arctic regions and the barely adequate nutritive value of winter food species indicate that muskox populations in northern regions will not reach densities which will support intensive utilization.
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