Elk Shift Resource Selection Temporally in Response to Natural Gas Development

Abstract

Resource selection is a process in which animals maximize resource acquisition through unequal use of heterogeneous resources on the landscape. Thus, shifts in resource and disturbance gradients should cause animals to shift resource use and distribution. Although there is an increasing body of evidence about the impacts of disturbance risk on wildlife populations, relatively few studies have assessed fine-scale impacts of human disturbance on wildlife. Our objective was to identify differences in day and night resource selection. Elk (Cervus canadensis) may be able to reduce consequences of coal bed natural gas development through expansion of resource use at night, thus ameliorating population impacts. To collect fine-scale temporal data, we used locations from 55 female elk equipped with Global Positioning System collars, as well as habitat and human disturbance variables for a study system in northeastern Wyoming. We used a mixed-effects model framework integrating frequency of individual elk to quantify shifts between day and night elk resource selection within a coal bed natural gas field. Elk exhibited differences in day and night resource selection, whereby they used areas with decreased forested cover and closer to roads at night. However, there was greater variation in resource selection at night compared with daytime. Our results suggest across each day, elk shifted fine-scale resource selection to take advantage of local resource gradients and response to disturbance impacts.