When you hear the phrase “Yellowstone predator,” what animal first comes to mind? A wolf? A bear? You may not immediately think of the elusive cougar, which is rarely seen by visitors, but ongoing research continues to reveal their secrets.
Cougars, along with wolves, were killed throughout the U.S. as part of the predator removal campaigns in the early 1900s. Wolves were completely eradicated from Yellowstone and, although cougars were probably eliminated, the species survived in the West. Working in their favor were the large cat’s secretive nature and preference for rocky territory where they are difficult to track. Sometime in the 1980s, the survivors re-established themselves in the northern part of Yellowstone and nearby areas of Montana.
DID YOU KNOW? Mountain lion, puma, catamount, and panther are four other names for cougars.Not long after, in 1995, human intervention restored wolves to their native habitat in Yellowstone. Since then, Greater Yellowstone has been a nearly complete ecosystem, with all of its historic predators intact.
So what does that mean for the park and surrounding area, with wolves, cougars and bears, as well as several smaller carnivores potentially competing with each other for territory and prey? How might this predator diversity affect the entire food chain?
Those are some of the questions the Yellowstone Cougar Project is hoping to answer. Following an eight-year gap in research on cougars, a new study began in the winter of 2014 to monitor the dynamics and ecological influence of Yellowstone’s charismatic and mysterious big cat, as well as the effects of predator diversity.
On the Trail of the Cougar
There are many ways to monitor and study wildlife. Previous cougar research in Yellowstone relied on radio collaring individuals to provide population estimates. This current phase of the Yellowstone Cougar Project uses noninvasive genetic sampling as the primary method to track the cougar population on the Northern Range of Yellowstone. This type of genetic sampling involves collecting and analyzing hair, scat, and blood samples left behind on the landscape by free ranging cougars.
The genetic samples provide researchers with a window into the lives of cougars. They can determine species and sex, and identify individual animals. From this data, they can estimate abundance, population growth rates, distribution, home range size, individual habitat preferences, and even some forms of social interactions.
Since 2014, snow-tracking surveys have been conducted weekly each winter along transects in cougar habitat on the Northern Range. When cougar tracks are detected, they are followed until discovering and collecting hair, scat, or blood (from nicks and scrapes on feet) as a potential genetic source.
DID YOU KNOW? Unlike lions and tigers, cougars are unable to roar, but they do communicate using a diverse array of vocalizations including growls, screams, and chirps.
Biologists record sign and presence of wolves and bears along each survey route, and document ungulate abundance.
In addition to tracking surveys, remote cameras are deployed along established game trails, carcass sites, and common cougar scent mark areas. Remote images and video footage capture exciting and scientifically valuable insights into the lives of these elusive and rarely seen carnivores.
The Study Continues
Since the last cougar research occurred in 2006, there have been significant ecological changes, including declines in elk and wolf densities, increasing bison and bear, and possibly more deer. A primary objective of this latest research phase is to see how cougar population dynamics and predation patterns have been influenced under these changing conditions. Preliminary findings show that Yellowstone is still an important core habitat for cougars in the Greater Yellowstone Ecosystem.
Since 2014, biologists have collected nearly 700 genetic samples (as of 2016) from free-ranging cougars. Of the approximately 400 samples that have been analyzed, 100 have yielded viable DNA to identify 20 unique individuals (13 females and 7 males). Results from the 2016 season are pending laboratory analysis. The team is also capturing and collaring several adult cougars each winter using advanced GPS satellite collars with activity trackers. These collars not only provide detailed stories about predation and habitat use, but also cutting edge information on animal energetics, or caloric costs and gains. In collaboration with the Yellowstone Wolf Project, this study will be the first to compare and contrast the animal energetics of being a wild carnivore in Yellowstone.
Ultimately, researchers hope to more fully understand the ecology of the cougar and the dynamics of systems where several top carnivores co-exist. This study will also help Yellowstone staff collaborate with other wildlife managers in parks where many carnivores reside.
Yellowstone Forever looks forward to sharing the progress and results of this planned five-year study as it continues.