Warren E. Johnson
Iowa State University
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Oecologia | 1990
J. Agustin Iriarte; William L. Franklin; Warren E. Johnson; Kent H. Redford
SummaryThe puma (Felis concolor) has the most extensive range of any terrestrial mammal in the Western Hemisphere, covering over 100° latitude. Food habits of different puma subspecies vary with latitude. Subspecies from temperate habitats generally eat larger prey and specialize on a smaller number of prey taxa, whereas, in tropical habitats, they prey on smaller, more varied prey. In North America, ungulates (primarily deer) represented 68% of the pumas diet by frequency of occurrence. Mean weight of vertebrate prey (MWVP) was positively correlated (r=0.875) with puma body weight and inversely correlated (r=-0.836) with food niche breadth in all America. In general, MWVP was lower in areas closer to the Equator. Patterns of puma prey selection are probably influenced by prey availability and vulnerability, habitat characteristics, and potential competition from the jaguar (Panthera onca).
Biological Conservation | 1999
William L. Franklin; Warren E. Johnson; Ronald J. Sarno; J. Agustin Iriarte
The ecology of the Patagonia puma was studied in Torres del Paine National Park, Chile. Thirteen pumas were captured from 1986 to 1989 and equipped with radio transmitters. During the winter of 1988 there was one puma per 17 km 2 in the 200 km 2 study area. Home ranges varied from 24 to 107 km 2 . Female home ranges overlapped with those of other males and females extensively, but male ranges overlapped each other for only short time periods. Seven adult pumas had home ranges extending outside the park boundaries and at least three preyed on sheep. Guanacos Lama guanicoe, especially young animals, were the puma’s most important prey item by biomass, but European hares Lepus capensis were preyed upon more than expected relative to available biomass. Of 731 guanaco skulls collected from 1979 to 1988, 33% showed clear evidence of having been killed by pumas. Over the past decade puma numbers are believed to have increased in the park, perhaps in response to an increase in guanaco numbers and continued protection. With decreased hunting pressure and harassment by horses and dogs, pumas have habituated to people and are being observed more often by park visitors. # 1999 Elsevier Science Ltd. All rights reserved.
Journal of Mammalogy | 1991
Warren E. Johnson; William L. Franklin
Archive | 1990
Agustín Iriarte; William L. Franklin; Warren E. Johnson
Archive | 1994
William L. Franklin; Warren E. Johnson; Torres del Paine
Journal of Mammalogy | 1987
Todd K. Fuller; Warren E. Johnson; William L. Franklin; Kurt A. Johnson
Archive | 2005
Warren E. Johnson; Larry Myers
Archive | 1992
Warren E. Johnson
Archive | 1990
J. Agust; William L. Franklin; Warren E. Johnson; Kent H. Redford
Archive | 1988
Warren E. Johnson; Todd K. Fuller; Gabriel Arribillaga; William L. Franklin; Kurt A. Johnson