Three of Oregon’s growing wolf packs, perhaps 20 wolves in all, now use parts of the Mount Emily Wildlife Management Unit between Pendleton and La Grande. The same area is home and hunting range for an estimated 100 cougars.
A study underway by an Oregon State University graduate student takes a look at what happens when two of the West’s iconic predators compete for food and habitat.
“Certainly from a science perspective, it’s a really cool study,” said Katie Dugger, an associate professor at OSU who is overseeing the research. Graduate student Elizabeth Orning is conducting the study as her Ph.D. dissertation.
As part of the work, researchers have placed GPS or radio collars on eight cougars and on at least one wolf each from the Mount Emily, Meacham and Umatilla River packs that frequent the area.
On her research website, Orning said increasing populations of large North American carnivores provide an opportunity to study two that share habitat, home ranges and prey.
The steady growth of Oregon’s gray wolf population, which has increased from 14 to 77 confirmed wolves since the end of 2009, made interaction with cougars inevitable.
“We could kind of see this was going to happen,” said Dugger, of OSU.
Although larger than wolves, cougars are likely to fare worse in the competition because they are solitary animals. Wolves travel in packs and can kill adult cougars, compete for deer and elk, chase cougars off carcasses they’ve been feeding on and force them into steeper, brushier terrain, Dugger said.
“We do expect wolves to change the way cougars use the landscape,” Dugger said.
The biggest impact of wolves on cougars might be an increase in cougar kitten mortality, Dugger said. A wolf pack could drive off a mother cougar or force her up a tree while it kills and eats the young or a sub-adult that doesn’t know enough to climb out of harm’s way. At least two cougar kittens are wearing radio collars as part of the study, Dugger said.
The study area is a geographical wildlife unit designated by Oregon Department of Fish and Wildlife, which is collaborating on the research. It includes portions of the Umatilla National Forest and the Confederated Tribes of the Umatilla reservation.