Yellowstone grizzly bear mortality, human habituation, and whitebark pine seed crops

Journal of Wildlife Management
By: , and 



The Yellowstone grizzly bear (Ursus arctos horribilis) population may be extirpated during the next 100-200 years unless mortality rates stabilize and remain at acceptable low levels. Consequently, we analyzed relationships between Yellowstone grizzly bear mortality and frequency of human habituation among bears and size of the whitebark pine (Pinus albicaulis) seed crop. During years of large seed crops, bears used areas within 5 km of roads and 8 km of developments half as intensively as during years of small seed crops because whitebark pine's high elevation distribution is typically remote from human facilities. On average, management trappings of bears were 6.2 times higher, mortality of adult females 2.3 times higher, and mortality of subadult males 3.3 times higher during years of small seed crops. We hypothesize that high mortality of adult females and subadult males during small seed crop years was a consequence of their tendency to range closest (of all sex-age cohorts) to human facilities; they also had a higher frequency of human habituation compared with adult males. We also hypothesize that low morality among subadult females during small seed crop years was a result of fewer energetic stressors compared with adult females and greater familiarity with their range compared with subadult males; mortality was low even though they ranged close to humans and exhibited a high frequency of human habituation. Human-habituated and food-conditioned bears were 2.9 times as likely to range within 4 km of developments and 3.1 times as often killed by humans compared with nonhabituated bears. We argue that destruction of habituated bears that use native foods near humans results in a decline in the overall ability of bears to use available habitat; and that the number and extent of human facilities in occupied grizzly bear habitat needs to be minimized unless habituated bears are preserved and successful ways to manage the associated risks to humans are developed.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Yellowstone grizzly bear mortality, human habituation, and whitebark pine seed crops
Series title Journal of Wildlife Management
DOI 10.2307/3808855
Volume 56
Issue 3
Year Published 1992
Language English
Publisher Wildlife Society
Publisher location Washington, D.C.
Contributing office(s) Northern Rocky Mountain Science Center
Description 11 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title The Journal of Wildlife Management
First page 432
Last page 442
Country United States
State Idaho, Montana, Wyoming
Other Geospatial Yellowstone National Park
Online Only (Y/N) N
Additional Online Files (Y/N) N