For centuries, Mexican gray wolves roamed the Southwest. But as cattle ranches spread, wolves became enemy number one, and by the 1970s the subspecies was nearly extinct. But after the Endangered Species Act was passed, the U.S. embarked on an ambitious plan to save the iconic predators. We’ll meet the Texas trapper who switched from killing wolves to catching them to breed. And we’ll follow a team of biologists into the Gila Wilderness to introduce captive-born wolf pups into the wild.
Listen on iHeartRadio, Apple Podcasts, Spotify, Stitcher, Castbox, Google Podcasts, and Amazon Music.
TRANSCRIPT
(Sounds of horses)
PETER GWIN (HOST): This is what it sounds like to explore New Mexico’s Gila Wilderness on horseback. On a recent assignment for National Geographic, I got to venture deep into the Gila with a photographer, podcast producer, and a backcountry guide.
The Gila is a magical place, filled with endless canyons, towering ponderosa forests, and ancient cliff dwellings. It’s also the nation’s first official wilderness area. Congress defines a wilderness as a place where natural ecosystems are left intact and humans are only temporary visitors.
(Horse whinny)
This idea of officially protecting wilderness can be traced back to a young forest ranger and the death of a wolf.
That story begins in the early 1900’s when a young forest ranger named Aldo Leopold arrived in New Mexico to survey land for the Forest Service. The prevailing philosophy of forestry back then was to manage the land for the benefit of the economy—think farming, logging, mining, and grazing. Part of Leopold’s job was to get rid of all the predators, which were considered dangerous nuisances.
But one day, after shooting a female wolf, the young forest ranger had a revelation. Aldo Leopold wrote about the experience years later.
A Sand County Almanac by Aldo Leopold: We reached the old wolf in time to watch a fierce green fire dying in her eyes. I thought that because fewer wolves meant more deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view.
GWIN: That encounter sent Leopold on a mission to change the way people thought about humans and their place in the environment. And thanks to his efforts, in 1924, the Gila became the first officially recognized wilderness area.
But his efforts weren’t enough to save the wolves. Eventually, they were hunted out of the entire Southwest, and the Gila was missing a crucial piece of its ecosystem.
OK, so cut to almost a century later, and here we are—the Nat Geo crew—exploring those pristine canyons that Leopold helped preserve, when one night, as we’re sitting around a fire talking about about Aldo Lopold—I swear this is true—we heard an unmistakable sound rise out of the night.
(Wolf howls)
The wolves are back.
I’m Peter Gwin, Editor at Large at National Geographic magazine, and you’re listening to Overheard, a show where we eavesdrop on the wild conversations we have here at Nat Geo and follow them to the edges of our big, weird, beautiful world.
This week: how hearing those howls sent me on a path to learn how wolves have made it back to the Gila. And check this out: one of the heroes of this tale used to be the wolves’ biggest enemy.
That’s coming up, right after the break.
But first, adventure is never far away with a free, one-month trial to National Geographic Premium. For starters, there’s full access to our stories online with new ones published every day; plus, every Nat Geo issue ever published is in our digital archives!
There’s a whole lot more for subscribers, and you can check it all out—for free—at natgeo.com/exploremore.
(Man howls, imitating a wolf)
This is the practiced and perfected howl of John Oakleaf, head of the wolf recovery program with U.S. Fish and Wildlife. One of the tricks he uses to find wild wolves is to howl into the night and see if any wolves howl back.
It’s a skill he says takes a lot of practice.
JOHN OAKLEAF (BIOLOGIST): So myself, I sounded terrible and drove along in a truck by myself and howled along with wild wolves that were on tape and got my howl down where I sounded OK and I could do it in front of other people. So that's how it goes.
GWIN: That's what I need, man. I need some wolf tape so I can practice. That's definitely what I've been missing. So tell me how is a Mexican wolf different than a gray wolf?
OAKLEAF: So Mexican wolves are a subspecies of gray wolves. And so they're the smallest subspecies. They're also the genetically most distinct subspecies that we can point to.
GWIN: Mexican wolves were the subspecies that adapted to the arid Southwest. John estimates that at their apex, there may have been tens of thousands of Mexican wolves living in the U.S. border states and Northern Mexico.
But by the late 1970’s there were none left in the US, and the only ones remaining were struggling to survive in remote mountains south of the border.
GWIN: What was the main cause of them going extinct?
OAKLEAF: Yeah. So it's people. It's the same major cause of mortality now. Basically wolves were the villains back in the day.
GWIN: Wolves and ranches don’t mix; cattle are defenseless against the predators.
Wolves especially like going after young calves and heifers. Heifers, young female cows, are extremely valuable. They are basically the future of a ranch because they will give birth to the next season’s calves.
In extreme cases, one wolf could kill four heifers in a single night. That’s a massive loss for a family-owned ranch. Because of this, ever since people began keeping livestock in the Southwest, they’ve been hunting and trapping wolves to protect their livelihoods. By the early 1900’s when Aldo Leopold arrived, the eradication of wolves had become systematic.
The U.S. government began a wolf extermination campaign. Bounties were put out for wolf hides, and powerful new poisons like strychnine accelerated the process.
By the 1960’s, the few that were around still killed cattle and the ranchers wanted them gone. But the wolves had adapted and learned to avoid the smells of humans. And that’s where Roy T. McBride enters the story.
OAKLEAF: Roy is kind of a unique figure. Most of the wolf folks know him for the traps that he builds. I grew up with McBride traps.
GWIN: Roy is a legend among people who study the Mexican wolf. Partly because he’s considered one of the greatest wolf trackers of all time and partly for the traps he invented that bear his name. But mainly, Roy’s a legend because he played a critical role in saving the Mexican wolf from extinction. I’d heard about this guy, but I wasn’t even sure he was still alive until I managed to get him on the phone.
ROY MCBRIDE (TRAPPER): My first name’s Roy. Thomas is my middle name. And McBride’s my last name.
GWIN: Although he’s 86 years old, Roy T. McBride still runs a cattle ranch in West Texas. We reached him on a landline telephone in a town nearby. Roy had a reputation as a trapper who could catch predators that no one else could, and not just in Texas.
McBRIDE: I went to Africa and a lot of places in South America. I caught snow leopards in Mongolia.
GWIN: Wait, what? Really?
McBRIDE: Yeah.
GWIN: So of all the animals you caught, all the different species, which one was the hardest to catch?
McBRIDE: The wolf.
GWIN: In one famous story, Roy was contacted by the owners of a large ranch in Mexico called Las Margaritas. They wanted him to track down a wolf that had been devastating their cattle. The footprints this wolf left behind were easy to identify because one paw was missing two toes from a close encounter with a trap. That close call also taught the wolf to be extremely careful around human smells because none of Roy’s normal traps worked. He boiled them in oak leaves and put traps on remote game trails where he knew the Las Margaritas wolf had passed before. But she never seemed to take the same path twice and wasn’t fooled by his attempts to camouflage the scent.
Roy tracked the Las Margaritas wolf across Mexico for 11 months as it went from ranch to ranch, eating cattle along the way.
McBRIDE: It killed 96 heifers in 11 months.
GWIN: Wow, one wolf, this Margaritas wolf killed 96 heifers.
McBRIDE: Yeah.
GWIN: Eventually, he noticed Las Margaritas’ prints near campfires, as if the wolf might be scavenging. That gave him an idea. He set a trap and burned a campfire on top of it and then put a piece of dried roadkill skunk on it.
Boom. Wolf caught.
And word spread that Roy T. McBride had caught the uncatchable wolf. Over the years, ranchers continued to hire Roy and other trappers to exterminate wolves, but slowly attitudes had begun to change.
In 1973, Congress passed the Endangered Species Act, which protected the Mexican wolf. U.S. Fish and Wildlife biologists knew the subspecies was close to extinction and realized the last chance to save the creatures was to start a breeding program. But they needed someone who could catch some of these rare wolves and bring them back alive.
So they called Roy.
McBRIDE: And by then, it was really hard to find them. There were hardly any of them left. But I got them enough to get their breeding thing started.
GWIN: It seems interesting that you kind of went from the guy that could get rid of wolves to the guy to save them. Did that seem like a strange turn of events to you when the government asked you, could you catch them and keep them alive?
McBRIDE: Yeah, I could see they were going to become extinct. So I was glad that I got to do that.
GWIN: After two years of searching south of the border, Roy estimated that there were probably only 50 wild Mexican wolves left on the planet. He managed to trap six, including a pregnant female. Between these wolves there was enough genetic diversity to breed healthy new generations.
The DNA of Roy’s wolves also helped biologists confirm that other captive wolves were pure Mexican wolves and not some other subspecies. In the end, U.S. Fish and Wildlife had seven genetically distinct wolves: four males and three females.
Let’s call them the Adams and Eves to reboot Mexican wolves.
GWIN: OK, so you start with seven. How do you restore wolves to this whole region of the country with just seven individuals?
OAKLEAF: Yeah, that's a great success story. You breed and you very carefully say, OK, I've bred these two now I got to do—for genetics, I got to breed this one and breed it back. And so you actually want to make sure you have genetic redundancy in captivity before you start ever reintroducing them in the wild. And so that's what we did. We started reintroducing in 1998.
GWIN: In other words, they spent 20 years carefully breeding the wolves in captivity, building up the numbers. So that the wolves that were finally ready to be reintroduced into the wild were the great-great-great-great—10-to-20 greats—grandchildren of those first Adam and Eve wolves.
John Oakleaf was there to see those first wolves released into New Mexico. At first it didn’t go well.
OAKLEAF: The first releases that we did in 1998 were largely unsuccessful, they almost died or, you know, stuff happened with them. And so then they brought them back in—a few back in—and paired them up again and released them again.
GWIN: Ever seen that reality show Naked and Afraid? Where people are dropped off in the middle of nowhere, naked, and need to figure out how to survive? That’s basically what was happening with those first wolves. Instincts can only carry you so far.
OAKLEAF: They get killing elk. They don't get avoiding, maybe, people very well. And so that was the hard part of it.
GWIN: Because they're raised around people and they're sort of more familiar, that's why?
OAKLEAF: Well, it's just—I guess they just don't have that, like they haven't had people shoot at them. There's no reason to be fearful of people. They haven't had—in captivity, we try to avoid any positive association with things, but you still have to feed them. You know, you still have to go in there every three days. And that's how you start a population. It was hard, hard work in the early days.
GWIN: Once a wild population is started, John explained that there is a much higher success rate with introducing wolves into the wild as pups. If a pup is successfully attached to a foster family, its new parents can teach it how to be a wild wolf.
But how do you get a wild wolf mother to adopt a captive-born pup? That’s coming up after the break.
(Car driving over gravel)
GWIN (in car): OK. It's 4:30 in the morning and I'm driving on a dirt road to a wilderness reserve owned by the state of New Mexico. And we are going to see some wolf cubs today.
GWIN (in recording studio): Last spring, I met up with biologists from U.S. Fish and Wildlife to watch the process of cross-fostering—that is, placing a captive-born pup into the den of a wild mother.
Most wild Mexican wolves are born in the wild. But because the population is so small, a few times a year Fish and Wildlife introduces some captive-bred pups to wild packs to make sure the gene pool stays healthy.
SUSAN DICKS (VETERINARIAN): 776 grams.
MELISSA KREUTZIAN (WILDLIFE BIOLOGIST, U.S. FISH AND WILDLIFE): So tiny.
DICKS: I know
GWIN: Susan Dicks, a veterinarian with U.S. Fish and Wildlife, removed them from a den inside a chain-link enclosure at the captive breeding facility. They’re little fluff balls of dark brown fur. Incredibly cute. Their eyes aren’t open yet. Susan weighed and examined them for birth defects—there were none. And then we drove for several hours right to the edge of the Gila Wilderness.
The switch needs to happen within several hours to give the pups the best chance to survive. So the clock is ticking.
DICKS: I know, hello, you look like you’re doing fine. Alright and I’m right handed So I open the mouth. They have no teeth. I feed it along the top of the mouth. The little one is feisty. This is a big one.
KREUTZIAN: You’re going to need help with that one.
GWIN: Once we got there, Susan showed a couple of her colleagues and me how to feed the pups so they’re topped off with one last meal. We were waiting to get the “all clear” from a scouting team who was already at the wild den.
DICKS: Can you take the needle off? Sorry about my teeth. Needle—whole needle off.
GWIN: Two boys?
DICKS: Alright, we can clean up our mess. Two boys.
NICHOLAS RISO: One’s feistier than the other.
DICKS: Yeah, the big one is mellow, the little one is feisty.
RISO: How many days old?
DICKS: Eight.
KREUTZIAN: Yeah, we were wrong. They’re eight days old.
GWIN: Eight days, got it, OK.
DICKS: I don’t know. Can’t count.
(Wind and hiking sounds)
GWIN: Once we got the all clear from the team at the den, the pups are wrapped in towels and carefully placed in a backpack. That’s where Nic Riso comes in, he’s a biologist with New Mexico Department of Game and Fish, and he’s the guy who’s going to carry the pups to their new home.
He shoulders the pack with our wolf cargo and off we head into the wilderness.
We hiked along a steep ridgeline, which offered a stunning vista of mountain valleys stretching to the horizon. There’d been a wildfire here. The ground was still charred, but new green shoots were coming up. And there were lots of elk droppings—plenty of food for a wolf pack.
We finally reached the den, which was a large hole near a big stump where a wild mother had given birth a little more than a week before. The advance team had already pulled out the wild pups and was examining each of them.
GWIN: How did the female react when you came?
RISO: So she wasn’t here when we got here, which is pretty typical. She heard us or smelled us or something. She flushed. So we kind of heard her last going over the ridge this way. So she actually wasn’t here. It took us longer than we wanted to find the den. ‘Cause this isn’t a pretty typical den. Usually it’s under a root ball or something like that. This one’s just in a hole in the ground.
GWIN: How many cubs are in the den?
RISO: So here we have six pups.
GWIN: And we’re adding two.
RISO: Adding two to get to eight total, which is more than a normal litter would be.
GWIN: Nic explained that wolves can’t really count, so the mother wouldn’t know the difference between six and eight cubs on sight. But she knew exactly how they smelled. That’s why the most important step in the foster process is to put together some wolf-cub camouflage. This is where it gets a little gross.
RISO: I’ve got a bag of their pee.
ED DAVIS (BIOLOGIST, US FISH AND WILDLIFE SERVICE): Lovely.
RISO: So we’ll do that when the golden shower happens.
GWIN: To keep their dens clean, wolf pups have evolved to urinate and defecate when prompted by their mother. She’ll carry her young outside and lick their abdomens to trigger the pee and poop reflex. This is lucky for the biologists because they need plenty of bodily fluids for their wolf-cub camo.
They used damp cotton swabs to get things flowing. Then the biologists gathered the pups into a pile and made sure all were completely covered in each others’ smells. How’s that for an introduction to life in the wild?
(Wolf cubs squeak)
RISO: So it’s OK, it’s just kind of going all over them, no big deal. OK, now set one down and go for one more. So that should be one for each of us—or two for each of us. OK, same thing. OK, we ready? Little pile. And yeah. So Paige, you’re going to have to really reach in here. OK, things are happening.
GWIN: Once the pups were all smelling the same, the team put them back inside the den. There was nothing left to do but leave and wait for the mother to come back, hopefully unaware of the two stowaways.
I just had to ask John Oakleaf, what the heck is going on inside the mother’s head?
GWIN (to Oakleaf): But, so here's the thing, though. OK So like the mother wolf leaves the den and she comes back instead of having six babies, she's got eight. And just kind of rolls with that? It's like, OK. You know, I mean—
OAKLEAF: A wolf's life is tough. And then the mom's like, Oh, I’m raising six puppies, eight it doesn't matter. Yeah, I think it's—
GWIN: But she doesn't react. she's not—like I mean, I guess the thing that I was struck by was just that like, you know, she just seems to roll with it, is what you're describing. Do you guys understand biologically, do you have any sense of why they do that?
OAKLEAF: Yeah, I think it's, they're heavy on hormones. And so the mother just very much wants to raise pups. And so you could put in more and she's going to try to raise all the pups that are in front of her. You just got to get those mothering instincts going. And wolves are good mothers.
GWIN: I interviewed John about a year after I helped bring those pups to their foster home in the wild. And he had an update for me.
OAKLEAF: I was in the helicopter this winter and we caught one of the cross-fostered pups that you helped put into the den there. That animal just left left its pack, went all the way up to like North Pinetop, Arizona from where you were.
GWIN: You’re kidding.
OAKLEAF: Not Pinetop, sorry Flagstaff, Arizona.
GWIN: That tiny wolf pup, just one year after leaving it in the wild den, made a roundtrip of more than 400 miles. It’s kind of incredible to think how fast that little fur ball had matured into a top-of-the-food-chain predator.
OAKLEAF: When you see it come to fruition and it and all this work pays off. It's an awesome, awesome thing.
GWIN: Are wolves now safe from extinction or are they on the road to being saved from extinction?
OAKLEAF: So, where are we? So one of the populations in the United States is at 240.
GWIN: It’s nowhere close to the thousands that used to live here, but they’re no longer on the verge of extinction.
OAKLEAF: They're in a much better spot. I have faith that we'll still be around well into the future.
GWIN: A century after Aldo Leopold had a change of heart about killing wolves, I think he’d be glad to know they were making a comeback.
(Howling wolves)
If you like what you hear and you want to support more content like this, please rate and review us in your podcast app and consider a National Geographic subscription. That’s the best way to support Overheard. Go to natgeo.com/exploremore to subscribe.
To read more of my reporting on the Gila, check out this month’s cover story on wilderness.
We’ve included a link in our show notes, they’re right there in your podcast app.
This week’s Overheard episode is produced by senior producer Brian Gutierrez.
Our other senior producer is Jacob Pinter.
Our senior editor is Eli Chen.
Our manager of audio is Carla Wills.
Our executive producer of audio is Davar Ardalan.
Our photo editor is Julie Hau.
Ted Woods sound-designed this episode and Hansdale Hsu composed our theme music.
This podcast is a production of National Geographic Partners.
Michael Tribble is the vice president of integrated storytelling.
Nathan Lump is National Geographic’s editor in chief.
And I’m Peter Gwin. Thanks for listening, and see y’all next time.
SHOW NOTES
Want more?
Check out Peter Gwin’s feature article on the Gila wilderness.
Thinking of visiting the Gila yourself? We’ve put together a travel guide for you.
Also explore:
In 2021, a Mexican wolf named Mr. Goodbar crossed the border from Mexico into the United States raising questions about how the border wall will affect animal migration.
The Gila wilderness is also famous for one of the only venomous lizards in the world, the Gila monster. But climate change and human activity is threatening this charismatic reptile.