Elk, mule deer, and white-tailed deer are valued as ecological, cultural and economic resources in Washington State. Ungulate population dynamics reflect competition for resources, habitat quality, terrain, weather and multiple causes of mortality. Wolves, cougars, bobcats, coyotes and black bears consume deer and elk in Washington, while human harvest, vehicle collision, domestic dogs, disease, and malnutrition cause additional ungulate mortality. We expect that the recolonization of wolves may lead to changes in the density and behavior of other predators in the wildlife community, with cascading impacts on these shared prey species.
Our aim is to determine how wolf presence influences deer and elk populations within a complex wildlife community. Specifically, we seek to explain the degree to which deer and elk are controlled by bottom-up effects (i.e., available forage) and top-down effects (i.e., predation or harvest), and which factors these populations are most sensitive to. We will also investigate how predator presence and density influence the movement and habitat use of deer and elk.
To answer these questions, we fit Global Positioning Satellite (GPS) collars on juvenile and adult female mule deer, white-tailed deer, and elk. Mule deer are the focal species within the Okanogan County study area, whereas sympatric white-tailed deer and elk are the focus in the northeast. We monitor the movement and survivorship of these animals. Mortalities are investigated using genetic evidence, tracks, and sign to determine the cause of death. From this information, we will determine how wolves and other carnivores shape the productivity of deer and elk populations, and how deer and elk change their movement in response to nutrition, habitat structure, and predation risk. Funding: WDFW, The Rocky Mountain Elk Foundation, The Hall Conservation Genetics Research Fund UW Project Leads: Laura Prugh (PI), Taylor Ganz (PhD Student)