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We collected 169 grizzly bear scats between 1994 and 1997 to determine the dietary habits of barren-ground grizzly bears (Ursus arctos) inhabiting Canada's central Arctic. From personal observations and fecal analysis, we concluded that barrenground grizzly bears lead a predominantly carnivorous lifestyle and are effective predators of caribou (Rangifer tarandus). Caribou was a predominant diet item during spring, midsummer , and fall. During early summer, grizzly bears foraged primarily on green vegetation. Berries increased in dietary importance in late summer. Declines in the caribou population of our study area or long-term absences of caribou may threaten the local grizzly bear population.

ABSTRACT. The results of analyses of rumen contents from 101 Peary caribou (Rangifer tarandus pearyi J. A. Allen 1902) collected on Banks Island are presented. Peary caribou on Banks Island were found to be versatile, broad spectrum grazers specializing on upland monocots, to ingest few lichens, and to exhibit significant seasonal and/or regional differences in diet.RkSUMfi. On présente les résultats des analyses du contenu des pans de 101 Peary caribous (Rangifer tarandus pearyi), rassemblés sur I'Ile de Banks. On a trouvé que ce végétaux, en particulier les monocottes de montagne, ils mangent peu de lichens et caribou avait un régime alimentaire diversifié; il broute une gamme assez large de les régions. montrent des differences significatives dans leur régime alimentaire saisonier et suivant Traduit par Alain de Vendegies, Aquitaine Co. of Canada Ltd.

Small rodent populations and conifer seedling survival were monitored on a reclaimed area in west central Alberta from September 1979 to September 1985. Although several species of cricetid rodents and shrews were captured during the live-trapping program, only meadow voles (Microtus pennsylvanicus) and deer mice (Peromyscus maniculatus) occurred in sufficient number to monitor annual changes in abundance. Meadow voles increased rapidly on the reclaimed area from 1979–1981, remained at high numbers until 1984, then declined sharply in 1985. Deer mice increased to moderate numbers from 1979–1981 and declined gradually until 1983. By 1984–1985, very few deer mice were present.Two species of conifer seedlings, lodgepole pine (Pinus contorta) and white spruce (Picea glauca) were planted on the reclaimed area in 1979 and 1980. Numbers of seedlings killed or damaged by small rodents, primarily by girdling, increased sharply in 1981 and remained at high levels through to 1984. Significant correlations between the percentage of the annual mortality of seedlings attributed to small rodents or the percentage of live seedlings damaged by small rodents, and the abundance of meadow voles the previous winter, indicate that the amount of mortality and damage to seedlings in this reclamation area is in part determined by the overwintering abundance of meadow voles. This is in direct agreement with conclusions from similar studies in other areas of North America and Europe.

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