Washington Predator-Prey Project

Predator-Prey Project logo on top of the University of Washington logo

The Washington Predator-Prey Project is a five-year research effort that began in the winter of 2016-17 to investigate the effects of wolves and their competitors on ungulate populations in managed landscapes. The project is studying the impact to ungulates (mule deer, white-tailed deer, and elk) from wolves that have colonized areas where they live, as well as other large and small carnivores such as cougars, bobcats, and coyotes.

WDFW scientists are collaborating with professors and graduate students from the University of Washington (UW) on this project, focusing their efforts in two study areas with varying levels of wolf presence. Those areas are in Stevens, Pend Oreille, and Okanogan counties. Within these study areas, researchers are outfitting deer, elk, wolves, cougars, coyotes, and bobcats with GPS radio collars to obtain information on the survival, sources of mortality, productivity, movements, distribution, and resource use of both predators and prey. Researchers are also deploying motion-sensing cameras and audio recorders to collect information on the behavior, interactions, and activity of predators and prey across space and time, and to test the utility of these non-invasive techniques to survey predator and prey populations,

Information gathered through this process will provide a greater understanding of predator-prey dynamics in communities with wolves, including the impacts of predation on ungulate populations.

What is Washington’s Predator-Prey Project Aimed at Achieving?

  • Assessing the effects of predation on ungulate populations in managed landscapes with wolves.
  • Determining the degree of influence wolves have on cougar space use, foraging ecology, and population dynamics.
  • Using the findings to address predator-prey and species-specific objectives outlined in WDFW’s 2016-2021 Game Management Plan.
  • Obtaining a greater understanding of Washington’s complex predator-prey communities for their improved conservation and management.
Washington state map showing the predatory/prey study areas with wolf pack ranges overlaid on top.
Project study areas and wolf packs

What has been done so far?

In the spring of 2019, researchers achieved all of their collaring targets for ungulates and cougars in both areas of the study. In the Okanogan, researchers collared mule deer, and in Stevens and Pend Orielle counties, they collared elk and white-tailed deer. In both study areas, wolves, cougars, coyotes, and bobcats were collared for the study. Researchers continue to collar animals in both study areas to maintain the number of collars in the field of all target species. Total ungulates collared since the study began include:

Species Adult Juvenile
Mule deer* 102  
White-tailed deer 96 97
Elk 56 20

In addition to the collars, 100 trail cameras and over 150 audio recorders were distributed across the project study areas. The Predator-Prey Project is currently in the third year of this five-year research effort. Researchers are gathering data on all target species, which involves many hours in the field throughout the year.The bulk of captures occur during the winter while mortality and kill-site investigations occur year-round. During spring and summer, UW researchers collar white-tailed deer fawns and elk calves in Stevens and Pend Oreille counties to document their survival and causes of mortality. For questions or more information on the Washington Predator-Prey Project, email wildthing@dfw.wa.gov and visit the Predator-Prey Project website maintained by collaborators from the University of Washington.

* Researchers are not collaring mule deer fawns for the project and focusing capture efforts for juveniles in the most eastern of the two study areas.