Decadal Growth of Traffic Volumes on Us Highway 2 and Implications for Grizzly Bear Habitat Connectivity

Abstract

I monitored traffic volumes on US Highway 2 between East and West Glacier, Montana, 1998-2001 as part of a study of the effects of transportation infrastructure on grizzly bears (Ursus arctos). I found that traffic volumes were below that where connectivity was impeded, but that some impacts to grizzly bear movement patterns could be measured. During the summers of 2012 and 2013 I replicated the traffic volume monitoring last conducted in 2001. I found that traffic volumes had increased dramatically, nearly doubling in some instances, and that some characteristics of traffic flow had changed. I discuss the implications of this growth in traffic to grizzly bear habitat connectivity.