Wildlife Responses to Motorized Winter Recreation In Yellowstone

During the winters of 2003–2007 researchers sampled thousands of interactions between people in over-snow vehicles (OSVs) and groups of wildlife that were on or near road corridors in the park interior. Surveys were conducted at least twice a week along various road segments. Each time that wildlife were encountered within 500 meters of the road, a pair of observers recorded group size, habitat, and distance from the road. Researchers also characterized the behavioral responses of humans and wildlife during encounters between them. The spectrum of possible human responses ranged from “no visible reaction” to “impeded or hastened movement by chasing animals or by forcing animals ahead of vehicles;” for wildlife, from “no visible reaction” to “attack/charge.”