Across Washington state, the average annual number of deer carcasses attributed to deer-vehicle collisions that were removed from state and federal highways between 2009 and 2014 exceeded 3,500 per year. Repeat mule deer-vehicle collisions have been documented in eastern Washington, including high levels along State Route 20 in Washington’s Methow Valley. WSDOT, in partnership with NGOs and other agencies, is working to identify where to install engineering solutions to reduce deer-vehicle collisions there. The objectives of this project are to determine the environmental factors associated with the frequency of deer-vehicle collisions, expand our understanding of why deer-vehicle collisions occur, and provide management recommendations to reduce the frequency of deer-vehicle collisions. To accomplish those goals, the researchers are quantifying expected frequencies of deer-vehicle collisions along SR 20, tracking individual deer encounters with proximity to the highway right-of-way, assessing the status of historical and current mule deer migration corridors, quantifying roadway and roadside landscape and habitat features, and creating a model and map of deer-vehicle collision risk across the SR 20 study area.
Principal Investigator: Jeffrey Manning, School of the Environment, WSU
Sponsor: WSDOT
WSDOT Technical Manager: Piper Petit
WSDOT Project Manager: Jon Peterson
Scheduled completion: December 2019