My work focused on the study of road effects and mitigation of negative impacts of roads on wildlife. Two different studies were conducted on Interstate 15, in southern Utah. My first study reported on road effects on small mammal communities. The results suggested that overall, there was no clear effect on small mammal populations relative to distance from the road. Most small mammal species did not appear to be negatively affected by the presence of the road. Instead, the road seemed to have either a neutral or a positive effect. The abundance and diversity of small mammals responded more markedly to microhabitat than to the presence of the highway. I suggest that other factors such as water runoff during rainy periods may be responsible for the detected patterns by increasing primary productivity in areas close to the road. I conclude that roads may often provide favorable micro-habitat in the desert landscape for many small mammals and that the disturbance caused by the highway use (e.g., noise, road surface vibration) seemed to have a negligible effect on these organisms . My second study examined the effectiveness of a mitigation strategy to reduce mule deer (Odocoileus hemionus) road mortality. Mitigation included exclusion fencing, earthen escape ramps, and underpass crossing structures . Results comparing mortality data before and after the mitigation showed 76-96% reductions of deer vehicle collisions. There was no evidence that the mitigation caused "end-of-the-fence" problems, i.e., higher mortality at the ends of the exclusion fencing . Results from underpass camera monitoring showed an increasing deer use of the underpasses over time. The volume of crossings recorded on new underpass structures approached the volume of crossings observed in a 20-year-old control underpass. My results suggest that human use and location of structures influenced deer use of underpasses. Overall results show that the mitigation strategy was effective and has reduced the number of deer-vehicle accidents while allowing easier wildlife movement across the landscape. I presented future maintenance recommendations to assure a long-term success for this strategy.

Sagebrush shrubsteppe ecosystems have increasingly garnered attention as an endangered ecosystem. Ninety nine percent of all sagebrush ecosystems are thought to have been impacted by humans, and over 50% of grassland and shrubsteppe species are believed to be in decline. Most of the research on sagebrush ecosystems has been conducted at lower elevations and in large expanses of sagebrush. A considerable amount of sagebrush is found at higher elevations, often in meadows found within a forest matrix. The role of this high-elevation habitat is poorly understood. We conducted bird, small mammal, vegetation, and soil surveys in sagebrush-dominated mountain meadows within the Wasatch-Cache National Forest in northeastern Utah. Meadows ranged from 0.6 to 782 hectares in size and included an impressive list of associated plant species. We detected two sagebrush-obligate species and numerous shrubsteppe-associated species. Each species appears to respond to different habitat characteristics, but all species that showed a significant relationship with meadow size were more likely to occur in larger meadows. Many species showed no relationship with size, suggesting that while larger meadows were preferred by some species, small meadows could also play an important role as habitat. While sagebrush-dominated mountain meadows were important for some species, we also failed to detect a number of species of interest. In particular, Sage Thrasher, Sage Sparrow, and pygmy rabbit were not found within the study area. North American Breeding Bird data suggests that Sage Thrashers can be found nearby. It is likely that these birds are only found in large expanses, and none of our meadows were large enough to support them. Sagebrush-dominated mountain meadows appear to be an important supplement to large expanses of sagebrush shrubsteppe habitat, but are not substitutable for all species.

No description available.