Grizzly bear: habitat relationships in the Yellowstone area

Bonnie M. Blanchard

doi:10.2307/3872528

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Grizzly bear: habitat relationships in the Yellowstone area

Bonnie M. Blanchard

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Abstract

Habitat use by grizzly bears ( Ursus arctos ) was studied from 1977 through 1979 in a 20,000-km 2 area with Yellowstone National Park in the center. Of 1826 aerial radio locations of 46 instrumental grizzlies, 90% were in timber. Three-fourths of the locations were 100 m or less from an edge between timber and an opening. Timber over 3 m tall with a canopy cover of 26-75% accounted for 50% of all activity sites from March through November. The Abies lasiocarpa/Vaccinium scoparium community alone contained 23% of the total activity sites and 35% of the forested activity sites. Of 507 observations of feeding activity, 45% were recorded in timber over 3 m tall with a canopy cover of 26-100%, 34% in timber with a 0.1-25% canopy cover, 20% in open habitats, and 3% in timber less than 3 m tall. Ninety-nine percent of examined day beds were in forested communities.

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Source-reported bounding extent: 44.1324° to 45.109° latitude; -111.156° to -109.8242° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Bonnie M. Blanchard. 1983. Grizzly bear: habitat relationships in the Yellowstone area. https://doi.org/10.2307/3872528

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