Evaluation of Wildlife Crossing Structures on U.S. Highway 93 Evaro to Polson

Abstract: On December 20, 2000 a Memorandum of Agreement was signed by the Confederated Salish and Kootenai Tribes (CSKT), Federal Highway Administration (FHWA), and the Montana Department of Transportation (MDT) allowing for the reconstruction of US 93 on the Flathead Reservation from Evaro to Polson, Montana. This 56.3 mile (90.6 km) project includes 42 fish and wildlife crossing structures and 14.7 miles (23.66 km) of wildlife-proof fencing. The magnitude of this mitigation is unprecedented and offers an excellent opportunity to evaluate the effectiveness of wildlife crossing structures to help guide similar mitigation measures in the future. It is commonly agreed animal-vehicle collisions and highway fragmentation of habitat are safety and ecological concerns that deserve attention. The breadth of cost/benefit information about various wildlife-highway crossing mitigation techniques is minimal at best. It is imperative to implement a scientifically based research plan to evaluate the effectiveness of the US 93 wildlife crossing structures. The evaluation results will be pivotal in the development of best management practices for future wildlife-highway impact mitigation projects and to help guide MDT and other state Departments of Transportation with the difficult task of providing appropriate transportation infrastructure while minimizing ecological impacts and animal-vehicle collisions. At the request of CSKT, MDT, and FHWA, the Western Transportation Institute (WTI) at Montana State University outlined a draft ten-year plan (3 pre-construction, 3 during construction, 3 post-construction, 1 data analysis) for the US 93 wildlife crossing structure evaluation. The drafted goals of the evaluation project are to determine what effect US 93 wildlife crossing structures and fencing have on the frequency of animal-vehicle collisions; the frequency of successful animal crossings and identify best management practices and further research with the US 93 reconstruction slated to begin in 2004, Phase I involves finalizing the research methodologies and collecting the baseline pre-construction data. The long-term research plan and data that result from Phase I will be used address the goals of the project. Essentially, Phase I research will determine the research approach that will be used to identify best management practices for future wildlife crossing structure and fencing deployments.

Sponsoring Organization: Montana Department of Transportation, Research Bureau

Completion Date: 8/31/2007

Additional Project Information: http://www.westerntransportationinstitute.org/research/426402.aspx