Effects of Population Density and Pack Size on the Foraging Ecology of Gray Wolves

  title={Effects of Population Density and Pack Size on the Foraging Ecology of Gray Wolves},
  author={Joanne M. Thurber and Rolf O. Peterson},
  journal={Journal of Mammalogy},
A decline in the gray wolf ( Canis lupus ) population in Isle Royale National Park prompted an intensive study of radiocollared individuals in 1988–1991, complementing an ongoing study begun in 1958. During winter, 1959–1991, the proportion of lone wolves was higher when the population was at low levels, whereas average size of packs declined with density of wolves. Sizes of territories (1971–1991) were not related to size of packs. In winter, food availability (kg wolf−1 day−1) and kill… 

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