Interactions between a large herbivore and a road network

Abstract

We assessed habitat selection of moose in a study area containing 2 highways and a network of forest roads in Quebec, Canada. We tested the hypothesis that roadways would affect moose habitat selection and that moose behaviour would vary with time, proximity to roads, type of roadway, and environmental characteristics (i.e., habitat and topography). We equipped 47 moose with GPS telemetry collars and assessed habitat selection using resource selection functions. Moose searched primarily for areas with high forage availability, but they also avoided highways and forest roads, although avoidance usually disappeared beyond 100–250 m. Avoidance was not directly proportional to noise disturbance; moose systematically avoided the first 100 m adjacent to forest roads, while habitats adjacent to highway sides were sometimes used in proportion to their availability. The benefits of using habitats adjacent to highways may be greater than the costs to moose, which was not always the case for forest roads. The road-avoidance zone varied seasonally but was generally wider for males than females, suggesting that males were more sensitive to road disturbance. We believe that moose frequent highways and associated roadsides to find food and mineral salts, and possibly to reduce predation risk for females. Topography was also an important correlate of habitat selection by moose, especially for females, which had significant selection coefficients for altitude and slope in almost every season. Proper assessment of human impacts on ungulates in natural environments requires consideration of unpaved forest roads. In a study area with a small human footprint and low road density (0.16 km·km−2), moose selection patterns suggested they minimized potential risks associated with highways at the coarse scale while seeking short-term benefits of highway roadsides, i.e., sodium in vegetation and pools, at the finer spatial scale.