Green Mountains Wildlife
Connectivity Study

Bolton-Waterbury, VT

7 MI
Trail Cameras
Wildlife Photos

Documenting Wildlife Movements where I-89 Crosses the Green Mountains


I-89 (Which also serves as U.S. Route 2) cuts across the Green Mountain range in Waterbury and Bolton, Vermont, bringing highway traffic through one of the most important and least fragmented forested habitats in the northeastern U.S. VTrans is interested in minimizing the risk of wildlife-vehicle collisions to motorists as well as determining the impacts to wildlife populations along this 7-mile corridor. The Project Team was tasked with determining what species occur within the corridor, their relative abundance, how and where they crossed the roadway, to what extent existing culverts and bridges were used, and ultimately where improved crossing structures could be implemented.


The study relied on trail cameras, winter tracking and GIS analysis to determine wildlife presence, abundance and movements. The project deployed 40 trail cameras in a system of 12 transects perpendicular to the road, 6 remote locations far from the road, and at bridges and large culverts under the road, resulting in over 35,000 wildlife photographs. Winter tracking was conducted over two winters and looked at wildlife movement across both the highway and local roads, through culverts, and under bridges. The GIS analysis incorporated these findings as well as landscape-scale factors to identify road-crossing hotspots and to target infrastructure that could facilitate wildlife passage.

The findings have the potential to improve motorist safety and reduce costs by reducing wildlife-vehicle collisions. It also has the potential to reduce wildlife mortality and improve the overall health of wildlife populations. Having intact ecosystems and healthy wildlife populations is important to the quality of life of both present and future Vermonters. The methods and results were shared with others in the region and presented at conferences.


  • ACEC VT Merit Award for Engineering Excellence: Transportation Category