Funded Research Projects: WS

Interactions between wolves and cougars in NE Washington

Research Sponsored By: Seattle City Light
Principal Investigator: Aaron Wirsing
Project Description
After an 80 year absence, the gray wolf (Canis lupus) is recolonizing the Pacific Northwest of the United States, dispersing from populations in the Rocky Mountains and the British Columbia coast. The future of wolf recovery in the Pacific Northwest relies on understanding how wolves interact with other predators and prey, and whether wolves provide positive ecosystem services in managed landscapes where logging, cattle ranching and hunting are permitted. In 2012, our team embarked on a landmark study to assess how wolves shape ecosystem processes in managed landscapes. The study focuses on how deer respond to the presence of wolves in Northeast Washington and whether wolves indirectly increase survival of deer fawns by suppressing coyotes. Here, we propose to broaden the scope of our study by assessing how cougars (Puma concolor) respond to the natural recolonization of wolves. The cougar/wolf interaction is important: cougars are second only to wolves in the apex predator hierarchy, targeted by hunters and are frequently persecuted because of their perceived impacts on livestock and people. Little is known, however, of how wolves and cougars interact in managed landscapes. The recent recolonization of wolves into Northeast Washington offers the perfect opportunity to undertake this research. Should wolves out-compete or displace cougars, changes in cougar abundance and resource use are likely. Such changes could have important, but unknown, effects on ecological communities, especially if cougars change the way in which they interact with prey species such as white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus). The goal of this project is to undertake groundbreaking research to understand the interactions between wolves and cougars. We will do this by analyzing the activity and behavior of cougars in areas with and without wolves. We hypothesize that cougars will alter their activity and foraging behavior in areas where wolves are present because of the consumptive (wolves killing cougars) and non-consumptive (wolves displacing cougars) effects of competition. We also hypothesize that cougar impacts on deer will be reduced in areas where wolves are present. To complete the project, our objective is to fit up to 35 cougars with GPS collars to allow movement, habitat and foraging data to be collected and then analyzed using sophisticated statistical and mapping software. This sample size will enable us to draw robust conclusions on the interactions of wolves and cougars in managed landscapes.