Effects of Road Characteristics, Land Cover, and Topography on Roadkill Patterns Across a Rural-Urban Gradient in Southwest Virginia

Roads are one of the most recognizable artifacts of human habitation and development. They cross various landscapes and expand with the increasing density of human settlements. While these structures are vital in facilitating vehicular transportation, they can also have unintended negative consequences for natural ecosystems, such as road-related wildlife mortality. To examine the negative impacts of roads on wildlife at a local level, I quantified the frequency and patterns of road mortality across a yearlong study period in a study area within Montgomery and Giles Counties in southwest Virginia. I also examined relationships between roadkill patterns and several land and road variables, hoping to close a current literature gap by focusing specifically on small and meso-mammals weighing less than 15kg. I recorded the location and species of carcasses found along predetermined routes, including roads with variable speed limits, road infrastructure, and adjacent land cover. I used government-provided data sets, satellite imagery, and field verification to characterize our study routes. I recorded 294 carcasses and identified 221, of which 84% were small or meso-mammals, including 11 taxa. The most frequent roadkill taxa were tree squirrels (Sciurus sp.), opossums (Didelphis virginiana), striped skunks (Mephitus mephitis), and raccoons (Procyon lotor). I found three roadkill hotspots, all along a major highway, and a high frequency of roadkill in spring, autumn, and early winter. High posted speed limits, the presence of artificial road lighting, and high proportions of forest and early successional growth cover (often present in pastures) were associated with an increased frequency of wildlife-vehicle collisions.