Tracking Yellowstone's Top Feline

For the National Park’s 150th anniversary, we’re supporting pathbreaking conservation research on Yellowstone’s other iconic predator—cougars.

Yellowstone National Park is known for its hydrothermal pools and fumaroles—including the spouting geyser, Old Faithful—roaming herds of bison and elk, and cars snaking through the park as tourists stop for a closer look at this beautifully preserved ecosystem that sprawls over 3,472 square miles, from the northwest corner of Wyoming to Montana, an area larger than Rhode Island.

Away from the rubberneckers, the quieter northern range of the park is a major hub of wildlife, arguably the most carnivore-rich spot in North America. Though the wolf, reintroduced in 1995, attracts most of the attention (and controversy), the cougar quietly reestablished itself here a decade earlier and continues to thrive on healthy prey populations. Their leading protector and advocate is Dan Stahler, a National Parks Service wildlife biologist who leads the Yellowstone Cougar Project. His work researching cougars’ movements and behavior is funded through Yellowstone Forever, the parks’ nonprofit arm, which Chantecaille is supporting in celebration of the 150th birthday of the world’s first national park.

Although parts of Yellowstone, including the northern range, remained closed due to devastating flooding and mudslides earlier this summer, the team’s work—which also looks at the effects of climate change on predator populations—eventually continued. We spoke with Dan Stahler from his base in the northern park about this elusive big cat.

A cougar in Northern Yellowstone

Tell us about the Yellowstone cougars: have they always been here?
Cougars have been part of these landscapes for thousands of years. They faced the same fate that other large carnivores like wolves did in the Yellowstone ecosystem. As the park was colonized by European settlers, wolves and cougars were trapped and persecuted. In the early 1900s, there was a US mandate to remove carnivores from public lands. Then when President Teddy Roosevelt visited in 1903, he actually put a stop to it. He was a hunter, but he also recognized that these animals have a place in landscapes like Yellowstone. Still, cougars were largely eradicated from the Yellowstone ecosystem at the same time as the wolves, by around 1925.

Cougars had been one of the most widely distributed large mammals in the Western hemisphere, going up into Canada and down to the tip of south America. That’s why there are all these different names for the same species: cougar, puma, panther, mountain lion, catamount. By the seventies, wildlife state agencies started managing cougars, which helped restore their numbers. They crept back in on their own to the Yellowstone ecosystem in the early 1980s and reestablished themselves in northern Yellowstone, an important winter area for the migratory ungulates (hoofed animals) like elk, bison, mule deer, bighorn and pronghorn sheep, because of its lower elevation and snowpack, providing food year-round.

How many cougars are there in Yellowstone and is it the biggest population in the US?
We have a resident year-round population of about 30 to 40 in Northern Yellowstone. (More cougars use the interior of the park in summer.) There are higher cougar densities in other parts of the West, but what makes Yellowstone’s cougars unique is that they interact with so many of the native species that we had here prior to European settlement. It gives us a vignette of what it probably looked like in many parts of the country prior to us meddling as humans.

A gorge in Yellowstone National Park

Why are cougars an important species for conservation?
Cougars are top predators—so they play an important role in influencing prey populations such as elk and deer, and shape food-web dynamics through nutrient recycling, therefore are important for biodiversity and ecosystem health.

“As we see increasing human development of landscapes, it’s becoming really important to have good knowledge about what cougars need to be successful and how we can better coexist with them.”

What does your work focus on?
Our current work is really trying to understand, through the long-term monitoring of cougars, how their population has changed over time with changes in elk abundance. We’re interested in what the impacts of climate change may be. And Yellowstone provides a really important protected core population where cougars will naturally disperse out of the park and go into the greater Yellowstone ecosystem, where they’re still an important part of that landscape. Cougars exist throughout a lot of the Western part of the United States. As we see increasing human development of landscapes, it's becoming really important to have good knowledge about what cougars need to be successful and how we can better coexist with them. Yellowstone is serving to help us understand that.

What are the greatest threats to cougars?
Like many wildlife species, the biggest threats are habitat changes and social intolerance. We have very few places like Yellowstone. What an animal like a cougar needs is the ability to have a safe place to live and raise offspring and find food. More and more, we humans are developing landscapes, breaking apart corridors that they need to maintain genetic health and connectivity. In California, there's a lot of big initiatives to develop crossing corridors on the interstate systems. The message is that we need to be able to learn to coexist with these animals and understand what their habitat needs are, what their prey and food needs are, to be successful.

A cougar in the snow and a wolf

How do cougars and wolves coexist with prey populations?
We've recently published some really fascinating work about cougars, wolves and elk. What we're finding is that the impacts of these carnivores on prey is not as severe as people think. Cougars are ambush hunters that hunt in rough, thick, forested areas at night, while wolves are more crepuscular, dawn and dusk hunters, in open flat areas. Using GPS data from cougar, wolf and elk collars, we showed how elk were able to respond differently to cougar risk. They avoided areas at night where cougars were and went down to feed in low flat areas when wolves weren't as active. And then when wolves were active, during the morning dawn and dusk, the elk would go back up into the forested areas where cougars were less active during that time of the day. So we were able to show really nicely with data how these animals are able to coexist on the landscape.

What will Chantecaille’s donation be used to support?
We intend to use the donated funds to buy GPS collars. We mark a handful of individuals every winter and use these GPS satellite collars to upload data every day, so we can track where they are in the landscape. We can search clusters to find what their prey is. Last winter, we finished our remote camera trap survey grid, putting 150 cameras across the study area that helps us monitor cougar numbers. We look at how these individuals interact with wolves and elk that wear GPS collars. We have these multi-carnivore, multi-predator, prey interaction studies going on, which has been really exciting.

“They’re incredible animals: their endurance, their strength, their ability to move over rough terrain and deal with a harsh winter environment like Yellowstone and still be successful is truly admirable.”