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Shelter is one critical aspect of an animal's habitat, providing refuge from predators and weather, protection for offspring, and aiding in physiological homeostasis. During the day, bats find shelter in roosts—spaces created under tree bark, in tree cavities, or between rocks—after spending the night searching for food. Finding a roost with a microclimate that enables bats to remain in their thermoneutral zone could reduce energetic demands or allow bats to allocate energy to other activities such as reproduction and fighting disease. We aimed to characterize the structural features and microclimate (i.e. temperature) of roosts used by male Little Brown Myotis (Myotis lucifugus) during the summer and determine whether bats select certain characteristics disproportionally to what is available at different spatial scales. During the summers of 2017 and 2018, we radio-tracked 34 male M. lucifugus in Lodgepole Pine-dominated forests. We located at least 1 roost for 20 individuals (average = 2.85 roosts/bat, range = 1 to 6). Although snags were available, most of the roosts were in rock features (86% in rocks, 14% in trees or snags). Male M. lucifugus were more likely to select rock roosts with less canopy closure that were closer to water compared to available roosts on the landscape. They also selected roosts in rock features occurring within larger areas of rock cover that had wider entrances and access to crevices that faced the sky; these roosts also had warmer microclimates relative to other locations available on the landscape. Crevices that allow the bat to bask in the sun and change locations within a roost, minimizing energy needed for active thermoregulation, could be very beneficial for individuals recovering from diseases such as white-nose syndrome. Our work indicates that rock features provide habitat for male M. lucifugus during summer; other studies have shown that bats roost in these features during autumn and winter, further supporting their importance. By protecting these important rock structures, managers can help bats meet their habitat needs throughout the year. [ABSTRACT FROM AUTHOR]

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.