THE WINTER BIOENERGETICS OF A BEAVER POPULATION IN NORTHERN LATITUDES

• Published in: Canadian Journal of Zoology
• Main Author: Novakowski, N. S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1967
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Northwest Territories; Wood Buffalo; Wood Buffalo National Park
• Online Access: http://dx.doi.org/10.1139/z67-121; http://www.nrcresearchpress.com/doi/pdf/10.1139/z67-121

The winter bioenergetics of a beaver population were studied in au area of Wood Buffalo National Park; which is located partly in Alberta and partly in the Northwest Territories. In these latitudes the beaver (Castor canadensis canadensis) are confined to subnivean existence for approximately 150 days each year. Although there is an unlimited supply of deciduous trees, which are cached by the colonies for this period, the caches were not sufficient for the energy requirements of the colonies, as calculated from the number and weight of animals in each colony. This indicates that energy deficits are a product of the winter behavior of the animals and that methods of energy conservation, such as reduced activity, periods of dormancy, huddling, insulation from ambient temperatures by lodge construction, and an increase in fur insulation and fat deposition provide the necessary mechanisms for survival. Based on a comparison of autumn and winter weights of beaver, the younger animals (kits and yearlings) increased their weight during the winter while the older animals, who presumably use fat reserves for survival, did not.