Road Ecology Center

Problem Statement One of the major challenges to grizzly bear preservation in the greater Yellowstone area is the impact on grizzly bear habitat selection by various types and intensities of human activities. The most prevalent of these human activities is the presence and intensity of use of motorized transportation systems. These transportation systems provide increased access into grizzly bear habitat and thus increase the risk of mortality and dilute the effectiveness of their habitat (Brannon 1984, Archibald et. al 1987, McLellan and Shackleton 1988, Kasworm and Manley 1990, Mace et. al. 1996, Matson et. al. 1993). Results of studies by Anue and Kasworm (1989) found that 63 percent of 43 grizzly bear mortalities on the Rocky Mountain front occurred within 1km of the nearest road. The Grizzly Bear Conservation Strategy Plan, a document developed for the management of grizzly bears, identifies the impact of motorized transportations systems as one of the key factors in the management of grizzly bear habitat. Metrics have been defined in the plan, including road densities, associated with motorized transportation systems and their use to monitor the effectiveness and change in grizzly bear habitat use. Even though there is a great deal of interest in the impacts of motorized transportation systems and their impact on grizzly bear habitat, there has been little research conducted to address this question in the Greater Yellowstone area. Most of the work that has been done in the Greater Yellowstone area has focused on Yellowstone National Park where road use is tightly controlled and firearms are not allowed. Areas managed for multiple use activities outside of Yellowstone National Park where road use has fewer restrictions and firearms are allowed have received little attention. Objective The emphasis of this paper is to look at the effect of two metrics of human use and their association with grizzly bear habitat selection.