Guardians of Yellowstone: The Yellowstone Cougar Project

(no audio) (gentle music) (gentle music continues) - Part of the magic of the cougar is because you rarely see them, they're this enigma.

It's that mystery, I think, that captivates the human passion.

You know, the questions you don't know the answers to.

And as a scientist, that's what we're really always inspired by, is, you know, what we don't know and what we have yet to learn, and there's I think a lot more to learn about cougars, and a place like Yellowstone is a way to cover more of that mystery.

- There will always be new things to learn.

I certainly didn't have the final story.

- I think we just have to acknowledge a little bit of humility to the fact that we don't know everything that we're gonna learn here in Yellowstone.

We don't know what questions we might be asking five years from now, 10 years from now.

- Spend time in the field and you start to learn these animals as individuals.

And when you get to see one in person, you just want more of that.

(gentle music) (gentle music continues) - Toni.

- Dan.

So good to see you.

- Yeah.

- Hey, buddy.

- Murph man.

- Good to see you again.

You guys wanna take a walk?

- Yeah.

(camera snaps) I'm ready.

- Let's do it.

- So what cat did you last have down in here?

- [Dan] Female 222.

Nubs.

- [Toni] Why is she called Nubs?

- [Dan] She's got a short tail.

And as you guys know, sometimes they frostbit tails, right?

- Yeah.

- But this one doesn't show any obvious sign of that.

Nubs made a kill down in the bottom here, just open sage.

But then she'd go and bed up into that country right there.

- Under the rim.

- Under the rim, during the day, watching across, then come back down.

- Interesting, as this was never a major- - Really?

- Hotspot for us at all.

(camera snaps) - She's really just kind of stuck to this area and is very successful.

Keeps raising litters of kittens, avoiding run-ins with wolves.

It's like she really has her home range dialed in.

- You know, knowing there's pretty secretive animals out here potentially watching us on, "What are they doing over there?

They're yakking."

(laughs) It's pretty amazing how successful they have been.

- [Dan] Yeah, we can learn a lot from them.

(gentle music continues) (gentle music) (gentle music continues) - We have a scientific objective with using these cameras, to get detections and to see how many cougars are on the landscape here.

But the bonus of having the camera traps out there, we get this rare glimpse into their lives and this look into their behavior, you know, interacting with some other animals, interacting with themselves, kittens.

You kind of know them a little bit at that point from all these trail cam videos.

- What it really reveals to us is, you know, each of these individuals have stories.

They have lives that are very personal, very important, full of strife and conflict.

And to get a glimpse of that is pretty magical.

- Most of the time, cougar walks by and you're like, yeah, maybe we could tell it's a male or female, but we don't know specifically what individual that is.

There's no stripes, there's no spots.

We kept seeing this cougar with a shorter tail and this just large goiter on her belly, so anytime she walked by, we knew, oh, this is Nubs, and she got the name, of course, just 'cause her tail's a little bit shorter, just a nubby tail.

So we ended up collaring her in 2020.

- We don't know the origin of her stunted tail.

We think it's possibly genetic.

And the reason we think that is one of her kittens, we call it Baby Nubs, has a short stunted tail.

(bright music) Kittens will spend the first couple years of their life with their mother, learning how to be a cougar.

- But now they have these videos of her just, like, playing with her kittens and chasing them and being chased by them, it's just like she's just being a caring mother that's teaching these kittens how to be a cougar.

Very important life of a young predator is just playing, right?

We need to learn how to run, chase, tackle.

- [Dan] Part of that behavior, we think, is of learning skills that will become important later in life when they're out on their own, hunting on their own.

(kitten chirps) - [Wes] It's really fun to see Nubs play her role in that rearing of her offspring.

(bright music continues) - When I first came to Yellowstone to work, we drove out to Lamar Valley, and I'll never forget, we saw the Rose Creek Pack up on the hillside, feeding on an elk carcass that they had killed from that morning.

And then a coyote came in, and they chased the coyote and killed it.

And so here I was, my first day on the job, experiencing just this wild, raw nature unfolding, wolves feeding on a bloody carcass, killing a competitor, a coyote coming in, and it just really made me realize how special of an opportunity we had.

(gentle music) Yellowstone is home to one of the most abundant and diverse assemblages of large predators.

Got grizzlies, wolves, cougars here, all interacting.

(wolf howls) There's few places on earth where those three species who have interacted for thousands of years together can do so largely unfettered by human influences.

When it was originally created, the primary reason was to protect the geological and geothermal wonders of Yellowstone, the hot springs, the thermal geyser basins.

But early on, it was also recognized as a mecca for wildlife.

But a wildlife community that was on its way out.

Poaching, overharvesting, market hunting, and the threats that were happening surrounding this wild place were so obvious to even some of the early visionaries like Teddy Roosevelt and George Bird Grinnell, recognizing that this place needed to be protected beyond just the other natural wonders such as the hot springs.

- [Wes] Of course, humans have been a part of the ecology in Northern Yellowstone for over 10,000 years.

There are Native American tribes that utilize the park, some year round, some seasonally.

And while we don't know exactly their impact on carnivore populations, what we do know is that when Europeans arrived along with them, government issued bounty programs.

These had a big impact on carnivores like wolves and cougars.

- If you look at cougars specifically in the Greater Yellowstone Ecosystem, they thrived here, up to the point where Europeans came into Yellowstone area and decided it was time to kind of control wild nature.

There was a large effort for predator eradication in the Yellowstone ecosystem, and they were very successful at it.

(upbeat newsreel music) (upbeat newsreel music continues) There was a lot of focused effort to poison, trap, and shoot all the carnivores, wolves, cougars, bears, coyotes.

Hounds were effectively used to eliminate not all, but probably the majority of cougars, at least to a point where they're no longer an ecologically functional population in Yellowstone.

(gun bangs) (gentle music) Teddy Roosevelt came to Yellowstone National Park, an avid hunter, and in his initial trips to Yellowstone under his presidency, he came out here with the goal of actually killing a cougar, and recognized right away, I think through some complications with getting houndsmen lined up to catch a cougar, that it would look bad for him to actually kill a cougar in a national park.

When he came here, he was witnessing severe winter, with a lot of starving elk and bighorn sheep and deer.

All these animals were dying a very painful death, and he kind of recognized that, "Hey, maybe if we had predators here, they could be regulated by other factors besides winter starvation."

And so he kind of recognized early on that, "Hey, maybe we shouldn't kill all the cougars from Yellowstone."

Ultimately, his thinking did not win out, because the park service at the time continued to eradicate predators.

You know, my job in the early 1900s as a park service employee would've been to kill carnivores, not to study them or try to save them.

By the 1930s, wolves and cougars both were fundamentally eradicated from this ecosystem.

And over a course of about 70 years, we no longer had an ecologically viable top predator, and the whole ecosystem changed.

(tense music) (tense music continues) (tense music continues) There were probably some cougars because of their secretive nature and living in remote areas that persisted, and so cougars recolonized Yellowstone on their own.

They did so because throughout the Rocky Mountain West, the bounties on cougars went away in most of the states in the '60s.

There was a passionate following of houndsmen that liked to work with their dogs and pursue cougars and hunt them and kill them, but because of their commitment to actually wanting more cougars out on the landscape and having the states recognizing that there was that stakeholder group, they managed limited quotas for cougars, and as a result, they probably crept back in on their own from the surrounding areas of Idaho, Montana, and Wyoming sometime in the '70s, and that's when the first surveys for mountain lions began.

(wind howling) (rhythmic music) - Would you like a map today?

- Yeah.

- There you go.

Have a good day.

- Thank you, dear.

Looking back on it, it was a feeling of exhilaration, a starting of something just amazing.

Oh, I remember being here with my dad, and Maurice Hornocker had asked me to come down and start the study, and my dad came up from California for a visit.

And I remember driving along with him, thinking, it's not as good a kind of habitat as I would've thought.

Well, I was on the wrong road.

We made a number of captures right up there in that rim.

I was married in this church.

(chuckles) So funny.

We were standing outside, and somebody drove by and rolled down their window and goes, "You'll be sorry!"

I was in my, you know, my suit.

(laughs) I loved it.

(laughs) - You still married?

- Yeah, same, yeah.

32 years.

It was out there in that dense lodgepole stand that we made our first capture of the entire project.

We had initially detected the family group of two kittens and the mother, F1, in that lodgepole stand.

And after a series of days, we finally discovered their tracks.

We turned loose my favorite dog, Old Spook.

So when we discovered him at the tree, he was five, 10 feet back away from the kitten, and we were able to make a capture that went really well, and marked the kitten and released it, and the family group got together again within a few hours.

(gentle music) - Kerry Murphy really was the first to develop the protocols on how we study cougars in a really rugged, tough terrain like Yellowstone.

He learned from Maurice Hornocker, who was studying cougars back in the '70s in the Frank Church Wilderness of Idaho, and Kerry really picked up the mantle from that and came to Yellowstone, in some of the most rugged, extreme, backcountry terrain, to collar cougars, study their food habits and predation, and we still use a lot of the methods that Kerry developed in the late '80s today in Yellowstone.

Just trying to get a location on female 210.

It's an adult female that we have wearing a GPS collar.

The one continuity between all our research phases has been the use of radio collars.

So I go to the left of where the strongest signal is until it fades, which is about there, and then I pan back to the right, and it fades about here, so this is kind of my arc, and you come to the center, and that's theoretically where that animal's transmitting from.

But if I really wanted to know exactly where she was, I would need to relocate myself and try to get 90 degrees from where I think this angle is.

And essentially, you can triangulate and use those sorts of bearings to figure out her location.

- First phase really was looking at the cougar population, knowing that wolf reintroduction was kind of on the horizon.

- Nothing was known at that point.

There were definitely some cougars in the system when we got here, but that's actually all we knew.

So, what would you wanna know?

You wanna know the social relationships, the population structure, how many males, how many females, how many kittens are born?

So, we call this in the wildlife business demography.

And the last thing you want to know about is prey.

What are the food sources, and what are the food sources of the food sources?

So if you can capture knowledge about those three things, you start (chuckles), you start to begin documenting the basic ecology of the species.

(gentle music) - Nobody had tackled, how often are they killing, and what does that mean for impacts on prey?

Nobody had done that.

That was Kerry Murphy.

- [Dan] They would just spend most of their winter efforts trying to put collars on as many animals as they could.

- It was very physically challenging.

You were walking across rough terrain, carrying a heavy pack every day for 30, 35 days.

It definitely took its toll on you.

But from a personal level, it was very, very rewarding to, in effect, walk in the footsteps of these cats.

We saw the same canyons and we visited the same places.

I remember finding some of those kills and was just so exhilarated, because you invested so much time and energy.

Then for just a brief moment, when you first saw the kill and you started to walk around, you had this sensation that you are in their world.

You see the world momentarily maybe like they're seeing it.

(wind howling) (wind howling continues) - They came up with pretty good estimates, and the numbers increase from the teens into the 20s and 30s, and even low 40s, at the height of their numbers, around the time wolves were being reintroduced and getting reestablished here.

(upbeat music) With both the top predators now back on the landscape together, it was a pivotal time in our understanding of ecosystem processes.

- The wolf population was rapidly increasing.

We were able to take this natural experiment with wolf reintroduction, and then we had a baseline set of data from phase one.

- This was the first place where we could really understand what happens when you have one top predator on the landscape, and you bring the other native predator that it evolved with back into the same ecosystem.

- Some of the questions we had are, if the wolves are dominant to cougars and they get displaced off of kills, is that gonna change their kill rate or their prey selection?

How are they gonna adjust to this new dominant predator in the landscape that they're typically subordinate to?

(wolves howling) I used the similar methodology that Kerry established to follow individuals to get at kill rates using VHF telemetry, and what that really took and meant is being out there every day in the field, following an individual or multiple individuals every single day, getting locations, looking at when you got clusters of locations that meant that there might be a kill there, or a cluster over a longer timeframe, whether it was a female that might be denning and having kittens.

Back then, it was just on data forms, handwritten data forms, and you'd have to pull that information back into your, you know, office, which was just in my house.

We worked outta my house as home-based, the entire field crew.

Doing the capture work, you're off trail, you know, scrambling through the rocks, where cats go.

You're always concerned about your crew, your team's safety, the safety of the dogs, and then ultimately, the safety of this animal.

And then you're going all day, going in in the dark, coming out in the dark.

At the end of the day, you know, you're exhausted.

There's a point where you're in really good shape, and then there's also a point where you're just halfway broken down.

But man, it was worth it.

(gentle music) And over time, looking at the data, we were able to notice a condensation of cats in the habitat, meaning what was good cat habitat became very important cat habitat.

For cats, secure habitat and secretive habitat is kind of that more rocky complex kind of forested landscape.

And so all of that just became more important.

We did document some mortality directly due to wolves.

Female 106.

She was eventually killed off on this side of Mount Everett by a pack of wolves.

When we got to her body, it was very fresh, and there were no signs of any trauma.

Nothing external, no blood.

And we actually did a full necropsy, and you could see all the trauma internally, because the wolves grab and then shake.

Her five month old kittens, then, that we had radio collared at that point in time, ended up below this cliff rim on the slopes of Mount Everett, above the Gardner River, and we were monitoring their signals, knowing that their fate would be death through starvation.

That was one of the hardest things for me during this study, having to know that these kittens would be suffering and starving.

Coming back to Yellowstone is like coming home.

This landscape is incredible.

And the way I got to know it was through following mountain lions day to day, and the places I got to see and how I got to understand and know was because a cat took me there.

It'll always hold a piece of my heart.

We expected to see some changes in terms of kitten survival being lower with wolf reintroduction, and what we actually saw was an increase in survival.

Ultimately, we found that the cats have made adjustments to this dominant competitor in this landscape.

(wind howling) - One of the things that we're learning in this current phase of work is that Yellowstone is still a place where cougars can thrive, and that's after nearly 30 years of wolves being back here.

That really says something about how special this place is.

This is one of the few long-term studies on cougars, particularly in a land where they're interacting with big changes of a wolf coming in and other carnivores being here.

There's very few in the world like that.

(gentle music) - [Toni] This third phase is just kind of continuing that look more in depth, and with new technology that we didn't have back in the first two study phases.

(gentle music continues) - This is some data for female 222, or Nubs, and we had been doing a predation sequence on her, where we try to link up to four successive kills.

You can see this heat map showing a cluster of points.

Everything about the data we see here indicates that there's a kill here.

So we're gonna go and hike into this area and investigate this, and this, if it is indeed a kill, would end the predation sequence that we've been following on her since about mid-November.

I'll get a kill kit.

Do you want to get the telemetry here?

- Yep.

I got a packet too, so I think we're good to go.

- [Dan] Okay.

(upbeat music) Cougars are always kind of outta sight, outta mind.

But that also fed into why the research itself is fun, is because it's a challenge to study cougars in Yellowstone.

With other large wildlife in the park, you can just get up in an airplane and count them.

Like, physically count.

We counted 6,332 elk today.

You can't do that with cougars, right?

You can't hardly see 'em when you know exactly where they are.

So, it was that challenge was what I was interested in.

You have to get into the backcountry.

(receiver buzzing) - Don't hear 210 or 222.

At least from right here.

- Head off to that cluster then?

- Let's do it.

- [Wes] I spent a lot of time working in Kenya, studying spotted hyenas.

All that work was just done in a safari vehicle.

So when I came back to the States, I was just looking for a job that let me hike all day.

- I think it's probably over by those junipers or that little clay buttresses.

See that little rocky thing?

- [Wes] The first few weeks were tough, and then I just kind of got in shape a little bit and got used to being in these rugged places, and then you can just focus on your job a little bit more and take a little bit more enjoyment out of it.

- [Dan] All right.

- You on it there?

- Yep.

- Nice.

- Nice cat track.

Looks like her.

I think it's an adult or a yearling, maybe.

We'll know here in a second, Wes.

Mandible.

- [Wes] Hey, look at that.

- Young.

It's an adult though.

Yearling maybe, huh?

- [Wes] Yeah, let's look at those teeth again, huh?

Calf.

- Oh, you're right, it is.

- It's a big calf.

- It is a big calf.

- Yeah.

Her kittens get older and older, she can't just afford to only kill smaller mule deer fawns and elk calf.

She's gotta go for cow elk every now and then, make bigger kills, take a risk to get more food for her kittens.

She'd probably like this spot.

She can kind of see out here.

- If I were to guess, you know, what had happened is there was a group of elk moving or feeding along the slope, maybe in the middle of the night.

That tends to be when they're hunting.

And she probably came up from below and was using this large sagebrush to kind of sneak in and stalk, and this elk could have been right here, and she came around the corner and just grabbed onto it and just pulled it right down and struggled with it right here and killed it.

I mean, that would be kind of a logical way that this particular hunt unfolded.

(upbeat music) About once a week, cougar will go out and have to take down some prey animal.

- A mountain lion has this capability to take large prey by itself.

- [Toni] Just with their forearms and their teeth.

- Gotta romp around the mountains all day, look for deer, look for elk, and get within about 10 meters of that animal.

In order to successfully hunt that, you know, a lot of times, you're hanging by their head on an animal that's four times your size.

- And the goal for them is to try to deliver a bite at the throat or the top of the neck.

Either grab and squeeze and suffocate, or cause enough blood loss for the animal to go into shock and die.

- Once cougars successfully hunt, it's not like the challenge is over for them.

- When it's got the prey down, it's got all this food available to it, 400 pounds, 500 pounds, I mean, that's great he's got this huge piece of food right there in front of him, but he opens it up.

Now he's got this problem, because all this scent is coming out, and you have all these other animals, and their tooling is to detect things by scent.

- You have to put so much energy into just trying to hide that carcass, just to not lose so much of this hard-earned meal.

Caching a carcass helps cover up the scent of it so that, you know, maybe the wolf or the bear walking by doesn't smell it.

But you just start to get this trickle of scavengers coming in.

As those magpies and the coyote or the bobcat start to come pick at that and then leave when the cougar comes back, that scent's just being spread more and more.

So, as time goes by, it's less likely that these other larger scavengers don't know about it.

You know, maybe a cougar can hold its own against one wolf.

It cannot hold its own against a pack of wolves or a black bear.

As impressive as cougars are, any time they have an interaction with these other apex predators and compete over a carcass, they're almost always going to lose that interaction.

- Imagine being a mother like Nubs, and she's got a young litter of kittens, she needs to feed them on a regular basis.

And she goes out, risks life and limb to take down a cow elk, is successful, gets beaten up and banged up a little bit, but makes a kill, and then just as she's getting ready to eat, you know, over the next half hour, a pack of wolves comes in and runs her off it.

And then she has to go out and try to do it all over again.

That's what they have to face day in and day out to be successful here.

And that's just the reality of living in a place like Yellowstone, with all these carnivores sharing this landscape together.

- That influences how often they have to kill.

But it also means that these cougars are providing a lot of food for several different species in Yellowstone.

So a lot of things are benefiting from cougars.

Nubs continues to kinda impress us with her story, because some of these videos shown, like, how injured she's been in the past, we have videos of her with essentially what looks like a broken leg at one point, carrying for two kittens that were about four or five months old.

And you see a video like that, you're like, "Oh, they're probably not gonna make it.

Like, how is a female gonna recover from this?"

But, you know, she figured something out.

She got healthy.

She was able to keep feeding those kittens.

So, both of her kittens and herself survived that.

Now you can't even tell that she had an injury like that.

(cougar chirping) (cougar chirps) - This is my first kill of 2023 to pick up, Wes.

- Oh, that's right.

Likewise.

It's a good one.

It's for our girl, Nubs.

- [Dan] Yeah.

(saw scraping) - [Wes] Well, it looks pretty good.

- We go to search all these kill sites because we have to connect a series of kills to come up with what we think is an accurate representation of their kill rate.

We can then estimate, you know, how many elk are being removed by Yellowstone's cougars, or how many deer?

- And there's the other front leg up.

I think we got it all here.

- And then from that, we can show how much also has potentially to be spread to the scavengers and the other species in the ecosystem that might, you know, benefit from a cougar kill.

There's still some food here for some scavengers, so this will not go to waste.

She's ate her fill, she's moved on.

Nubs got a good meal here, so kind of fun to stay connected with her through her meals.

(upbeat music) (upbeat music continues) (airplane buzzing) (upbeat music continues) (upbeat music continues) (upbeat music continues) - To personally experience the landscape and the interactions and all the components, there's so many layers and nuances of this ecosystem, and then it's just stunning.

Our ability to come in and be able to study and learn from this place, it's just incredible, and you want every person to be able to experience just some little aspect that they connect to.

- [Dan] As a young child, you know, the dream I had to work with wild animals, and the fact that I've been able to spend my career here studying these charismatic, just amazing animals, it's something I'll never take for granted.

- It'll always be part of my fiber.

It was one of the best times in my life.

(upbeat music continues) - There's days where you wake up and you know what's ahead of you, if you're gonna go try to collar a cougar or go search one of their clusters.

What keeps you going is just realizing that these animals are out there doing that every single day.

Take a 10-year-old cougar.

365 days a year.

Think about, over 10 years, what that animal's had to do.

And if she can do that for 10 years straight, I can do it for a day.

- [Toni] We wouldn't be able to understand anything about mountain lions without getting them captured and putting collars on 'em.

- [Dan] And that might sound simple, but it requires a lot of coordination, a lot of effort of people in the back country of Yellowstone.

- The idea is that we need to get to a place where we're fairly close to that cougar.

We just find tracks, and then we can release the hound dogs.

- We could spend days and days in the field and hit cat track after cat track.

We wouldn't be able to catch up with it or ever find it.

So, by using hounds, we're able to sniff out that track, pursue the track, and ultimately, catch up with the animal.

(upbeat music) - The first time I ever went out, I actually walked away more impressed with the dogs than I did seeing a mountain lion.

(dog whines) - A lot of houndsmen, they don't care so much about killing the cougars.

They care about working with their dogs to get a cougar up a tree.

- It's just a way that I enjoy the outdoors and dogs.

It all fits together for me.

It's a working relationship.

(dogs howling) (dogs barking) Some of the things I've seen while running these dogs that cougars do, the way they live, the terrain they make a living in, it's incredible that an animal does what they do.

(dogs barking) - Some of the best houndsmen that I've worked with, they're actually some of the best lion conservationists there are, because if you wanna work with your dogs and capture a lot of cougars, you can't have these high quotas that will eliminate the cougar population.

Then you won't have anything to chase.

And the thrill for them is working with those dogs and just to see a cougar up a tree, take a photo, and walk away.

- I respect the animal.

I'm curious about the animal.

I read books about cougars.

That's why I work with Dan on this study.

- The behavioral response of being chased by something like a wolf and barked at, the cat runs up the tree.

That's the evolutionary characteristic or behavior of mountain lions, the escape mechanism.

And that enables us to catch up to that individual and be able to mark it and handle it.

- So once we get to the tree, essentially, what we're doing, we're darting that cougar with ketamine, but with no sedative.

- [Dan] All right, let me know when you guys are ready.

One, two, three.

Dart's in, is the plunger forward?

- Yes.

(dogs howling) I see red in the middle.

I don't see a black plunger right now.

- I bet it's forward.

Let me get my dry notes.

I think that plunger's forward.

- [Wes] Once that drug is on board, it's safe for a tree climber to go up there.

- That might come down when- - It is up in the tree still.

- The cat.

- Unless it's head high on the other side of the tree.

- That cougar's not sedated per se, but it's not really with it, it's not, like, aware of its surroundings.

Um, I gotta get on the other side of this real quick.

And so then we can use some ropes to, you know, secure the climber right in that spot, and then use a belay rope and some hobbles to attach it to the cougar itself and lower it down from the tree.

(gentle music) (dogs barking) - [Dan] Can you see if I can lift him up a little bit?

- Once we get that cougar on the ground, we're gonna add a sedative so it's knocked out at that point.

That's when we get to work, putting on a GPS collar, taking measurements, drawing blood.

It's like, get as much information as you can from this cougar while you have it sedated, because it's such a long and difficult process and it's stressful for the animal to get to that point, let's get as much information as we can while we have it on the ground.

- [Dan] They are giving us their time, maybe unwillingly, but we really value that time with that animal.

We have a very specific suite of questions that we're asking.

We will weigh them.

That gives us an overall data point on their health and their fitness.

Are they in good condition?

Are they in poor condition?

What is the average weight of an adult male or female cougar in Yellowstone?

How does that compare to cougars in other parts of the world?

73.

We measure their teeth and their gum recession in their teeth, and that allows us to give an estimate of age, accurately.

It's sometimes difficult to age wild animals.

Gives us information about lifespan, age specific survival rates, reproductive rates.

- It's seven.

- Shoulder, right?

- Right in the shoulder, yeah.

- Yeah, I'll just do that one.

- Paramount to the capture process for a cougar in Yellowstone is making sure its wellbeing is taken care of.

Once we finish the whole handling process, we've put the collar on, we've collected the samples we need, we watch that cougar recover from the drug, the drug we use allows it to wake up, and we watch it walk off.

We make sure it's safe from water, from cliffs.

It is our responsibility to make sure that that is a safe and effective capture.

In the days that follow, we will monitor that animal very closely, 'cause we can track the movements of that animal.

And I really don't sleep well or breathe easy until I see that cat make its first kill.

And we take a lot of comfort in seeing that small disruption in its life caused by us is very short-lived.

This is a Vectronic accelerometer collar.

Vectronic is the company that makes these.

This number five here is a visual cue for us.

When this animal triggers our remote cameras, we can identify which cat it is.

Known animals triggering cameras across the landscape, across our remote camera grid, that feeds into our population estimation model.

- So in phase one and phase two, those projects had to use an incredible amount of manpower.

The use of remote cameras along with some newer modeling approaches has allowed us to do more with less.

So we just got to one of our camera stations here.

Like, that whole area that we can see in the background IS really good cougar habitat.

Then over that way, we got some really good winter cougar habitat as well, so this is kind of the way to get in between.

With all this cover, they feel safe here.

This will be the third winter that we have this camera station operating.

It's really important for us to get the collar on the cougar.

Does it have a collar or not, and what's the belting info on that that we put on there?

It's the numbers.

Some reflective tape.

So when that cougar walks by, we know it's this individual.

That's really the core information that we get from these cameras.

And we apply that to all the uncollared cats in this population, and that's how we get to abundance estimates.

And then we also have two cameras at every one of these stations.

We have one here and we have one over there.

So we can actually identify the sex of a cougar if we see the rear end of it as it walks away.

So a lot of times, we'll have these cameras pointing different directions on the trail.

So, no matter which way that cat goes, we have one camera that can look at that rear end of the cat and say, "Oh, that's a male or female."

- So, with fewer cats collared, we can still get reliable estimates about how many there are.

This one's all set, Wes.

In addition to all of the other things the cameras allow us to do.

- Yep, we're good over here too.

- [Dan] Which includes analyzing other wildlife in the park.

The cameras do not care what walks in front of it.

They will capture videos of any warm bodied species that goes in front of it.

(gentle music) (gentle music continues) (gentle music continues) (gentle music continues) (wildlife chirping) What are we up to today, Wes?

- Out here in the Slough Creek drainage.

Gonna go check out a Nubs cluster.

It's over there, up on that little rocky bluff in the trees.

(birds chirping) That's just the center of a big cluster point that we had for her in this area.

I think she was here for two or three nights, so, there's definitely something that she was eating on here.

(wildlife chirping) (wildlife chirping continues) - [Dan] May have something up here, Wes, for a little cache.

Yeah, I got some marmot hair.

Yep.

Right here is some marmot hair.

And kind of what caught my eye is this grass right here all kind of disturbed, looked like something had been buried.

And there's not much left.

As we dig into this, we might find a little bit more.

But, right here, Wes.

- You can usually bet, especially in these steep places, that you're gonna find some of this stuff on, like, the little flat bench somewhere, 'cause they still want to find a comfortable spot to eat.

- Yeah.

- And to cache it.

They can't really do that on a steep slope.

- [Dan] Wonder if we'll find any bone or anything.

Dig in here a little.

Part of the lower mandible.

- Oh, oh, oh, there it is.

- [Dan] Yep.

Wes' mandible.

- [Wes] Oh, what is that?

- [Dan] It's a tooth?

- [Wes] Yeah, no, that's a lower incisor.

- Lower incisor of the marmot.

- Uh-huh.

- Yep.

- That's cool.

Looks like just a nice marmot, and kind of makes sense given that we are getting barked at by 'em as we hiked up into here.

(gentle music) I'm guessing, you know, an adult marmot's gonna weigh maybe 10 pounds.

So even though this is a small prey package, it's a good little meal.

- Nubs is by herself, and she doesn't have to provide for, you know, two, three other mouths right now, which means she doesn't have to risk going after a bigger prey like an elk.

It's a pretty safe decision for her.

Probably why she was hanging out here for two or three weeks.

I suspect she got a few more of these guys.

- Yep.

(gentle music continues) August 30th, 2023.

Last evening, I got a mortality message from the collar of female 222, or Nubs.

And those messages are sent out from these GPS collars if they have stopped moving for more than 12 hours.

So usually they indicate a mortality, and we're gonna go investigate this morning.

I hope not, but won't know until we check it out.

I remember the evening I got a text on my phone telling me that Nubs' collar had gone into mortality mode.

And my heart sank, because as much as you try to remain detached from the animals that you follow, you're just connected to them in a very personal way.

I remember the first time I saw Nubs in a tree, trying to capture her, and I didn't capture her that day.

I remember the first time she ever triggered a camera in 2016, with that short tail.

And so when I had the sense that she probably had died, I felt sadness, because she was a friend.

She didn't know it, but she was a cat that I was connected with.

She was a big part of my life in many ways.

Sort of a symbol of sort of my life here as a biologist in Yellowstone.

There's a key point in my time with her where my son, Rocco, and my wife, Erin, was with me during a capture, and that was a really important moment in my career and my fatherhood, and being a husband with another biologist.

And so that all came together in a moment when realizing the life that I had been following for about, you know, a decade of this cat, had, you know, maybe come to an end.

And that really resonated with me.

But then I had a job to do.

And that next morning, our team went out into the field to determine if in fact she had died.

(wind blowing) (wind blowing continues) (wind blowing continues) So it almost looks like maybe off that ledge of that rock or that cave or something.

- Yeah, right in there.

- There's a little entrance down below.

I don't know why I have in my head that she's in something, but... I can smell her.

And, oh, yeah, there she is.

Hm.

Resting above her homeland.

Thinking we kind of take an initial look and then go from there.

I won't touch her or anything yet until we can kind of check her out a little bit closer.

(wind blowing) (wind blowing continues) I mean, these are wild animals that are out there day in and day out, 24/7, 365 days a year.

They have to go out there, feed themselves, raise families, deal with all the risks and challenges that they face every day, and despite that adversity, they persist.

But they're only here for a short time.

You can think about an individual like Nubs as just another cat in the population.

And you know what?

They're gonna be born, they're gonna die, and that's just Yellowstone, and that's nature.

We are interested in those population level questions about cougars, but you can't really separate that connection you have to those individuals, even as a biologist, and nor should we.

I think we are gonna be better stewards, we're gonna be better at unraveling their mystery when we do connect to those individuals, 'cause they tell us the stories that a data point can't, that give us the more complete picture of Yellowstone.

So I feel lucky to have known her.

(gentle music) (gentle music continues) (gentle music continues) So much about the lives of cougars are secretive and mysterious, and that's okay.

As hard as we may try as biologists to kind of understand completely, there's always gonna be new mysteries to solve.

- The more you learn, the less you feel you know at times, and the more you want to learn.

- When you look out on the landscape of Yellowstone and you see the panorama, there is a cougar out there somewhere, sitting there on a rock ledge.

Many people will never see that, but they are symbolic of so much more we're not seeing.

- It's a revelation that the story is much bigger than you thought it was.

(gentle music continues) (gentle music continues) - Nubs' legacy continues here, and we get to watch that legacy play out through Baby Nubs.

Even though she's not collared, every time she hits a camera, we know it's her, and she's using all these areas that Mom showed her in this pristine part of Northern Yellowstone.

So, while Nubs is gone, and we were very sad to see this cat that we grew to know so well go, we still have Baby Nubs, we still have another cougar that we recognize in this landscape, teaching us more about what these cougars mean to this ecosystem.

(uplifting music) (Baby Nubs chirping) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (uplifting music continues) (upbeat music) (upbeat music continues) (upbeat music continues) We got a dog getting up in the background here.

Oh, you did pretty good, pup.

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