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P.K. Kennedy

Publications and source records attributed to P.K. Kennedy.

2 recordsLinked to original sources

Taxonomic assessment of the black bear (Ursus americanus) in the eastern United States

The subspecific status of the Louisiana black bear ( Ursus americanus luteolus ) and Florida black bear ( U. a. floridanus ) were assessed using morphologic features to determine their distinctness in relation to one another and to the black bear ( U. a. americanus ). Forty-four dimensions were recorded from skulls of 125 male and 127 female adult (4.5 years or older) bears. Results showed skulls of U. a. luteolus, U. a. floridanus , and U. a. americanus to be similar in morphology. However, features of U. a. luteolus , and U. a. floridanus tended, in general, to be larger and shaped differently than those of U. a. americanus . Differences between measurements of U. a. luteolus and U. a. floridanus were less apparent than those between either of these taxa and U. a. americanus . For U. a. luteolus and U. a. floridanus , means of most characters differed only slightly, and ranges of all measurements overlapped to some degree. Yet, small numbers of characters that reflected molar tooth measurements or features relating to dentition, height of frontal region, and skull length and width appeared to correctly classify these taxa in most cases. Results were interpreted to support the subspecific recognition of U. a. luteolus, U. a. floridanus , and U. a. americanus .

Southwestern Naturalist↗

Geographic variation in the black bear (Ursus americanus) in the eastern United States and Canada

The pattern of geographic variation in morphologic characters of the black bear ( Ursus americanus ) was assessed at 13 sites in the eastern United States and Canada. Thirty measurements from 206 males and 207 females were recorded to the nearest 0.01 mm using digital calipers and subjected to principal components analysis. A matrix of correlations among skull characters was computed, and the first 3 principal components were extracted. These accounted for 90.5% of the variation in the character set for males and 87.1% for females. Three-dimensional projection of localities onto principal components showed that, for males and females, largest individuals occurred in the more southern localities (e.g., males--Louisiana-Mississippi, eastern Texas; females--Louisiana-eastern Texas) and the smallest animals occurred in the northernmost locality (Quebec). Generally, bears were similar morphologically to those in nearby geographic areas. For males, correlations between morphologic variation and environmental factors indicated a significant relationship between size variation and mean January temperature, mean July temperature, mean annual precipitation, latitude, and actual evapotranspiration; for females, a significant relationship was observed between morphologic variation and mean annual temperature, mean January temperature, mean July temperature, latitude, and actual evapotranspiration. There was no significant correlation for either sex between environmental factors and projections onto components II and III.

Southwestern Naturalist↗