The wolf is theworld's largest dog– a top predator andan iconic animal that roamed freely across NorthAmerica for tens of thousands of years.
But in the early 20thcentury, a ruthless war was waged against thesecunning carnivores in an effort to stop them preyingon livestock.
This resulted in the gray wolfbeing almost completely wiped out in the continental US.
But then, in 1995, a controversial wolf recovery programbegan in Yellowstone with surprising results.
Here's my journey in searchof America's elusive canine.
[music playing] [eagle screeching] This is the most remote area inthe contiguous United States.
The world's firstnational park– Yellowstone.
I'm landing at LoneMountain Ranch.
It's a NationalGeographic Unique Lodge.
I'm just a short driveaway from Yellowstone National Park, where thereis an abundance of wildlife.
5, 000 bison.
And then they've got grizzlybears, and also wolves.
And that is the animal thatI'm going in search of.
Wolves were effectivelywiped out in Yellowstone, eradicated formore than 70 years after a bounty wasput on their head.
Without this apexpredator, the balance of Yellowstone's ecosystem wasthrown completely out of whack.
Trees and grasses vanished.
Vast tracts of the once-greatwilderness were stripped bare.
Today, there are about 100wolves roaming Yellowstone National Park, a sprawlingterritory more than three times the size of Rhode Island.
The wolves are out there, but they're hard to find, which is why we're hookingup with Doug Smith.
Doug is the lead wolfbiologist in Yellowstone.
How you doing? Welcome to Yellowstone.
Oh, thanks very much.
We got a good day.
This is wolf weather.
I got a crew on thatbutte right there right at this moment tracking wolves.
PHIL KEOGHAN: Whatare the chances of us seeing a wolf near? DOUG SMITH: Well, it'sreally hard to find them.
I'm just going to do alisten, this plateau here.
PHIL KEOGHAN: You can actuallywork out where they are.
That's kind of cool.
DOUG SMITH: Oh, yeah.
Well, with these wolves, we collared in December.
And they've beenhanging around here.
I'm not getting a signal here.
Do you have anyvisuals up there? PHIL KEOGHAN: Sothey're all around us, but trying to pick them outof the wilderness is tough.
But we'll go out andsee what we can find.
All right, sounds good.
[atmospheric music] Yeah, there's somebison tracks here.
Some elk as well.
That's mostly whatthe wolves are after.
They don't like preyon the bison so much, I think for obvious reasons.
PHIL KEOGHAN: Yeah.
DOUG SMITH: It does.
PHIL KEOGHAN: Yeah.
Off in the distancethere, bison.
[tense music] They may look docile, butbison are one of Yellowstone's most dangerous inhabitants.
With adults weighing overa ton, they're the largest land mammal in North America.
Despite their size, they're incredibly agile and can reach speedsup to 35 miles an hour, and have a history of charginghumans if they feel threatened.
DOUG SMITH: We're going tohave to belly around them.
Skirt around them.
I like that idea.
PHIL KEOGHAN: So it'sa 2-million-acre park.
And how many wolves in allof Yellowstone, do you think? DOUG SMITH: About 100.
PHIL KEOGHAN: So that'sa pretty tough challenge.
DOUG SMITH: Oh, yeah.
Well, we radio collar them.
All our studies are basedupon having marked wolves.
PHIL KEOGHAN (VOICEOVER):Doug and his team can only keeptrack of the wolves if they catch and collar them– PHIL KEOGHAN(VOICEOVER): –which they do once a year midwinter.
PHIL KEOGHAN: You got it? DOUG SMITH: This is astandard VHF collar.
The pups, we can't putthe collar on too tight.
It will still grow.
We do a full physicalexam, and these are fully-developed adult teeth, and there's not much wear here.
This is a wolf probablyin the prime of its life.
PHIL KEOGHAN (VOICEOVER):Monitoring the wolves' growth– DOUG SMITH: 122.
PHIL KEOGHAN (VOICEOVER): –aswell as taking blood samples provides importantdata of the pack's overall health, genetic makeup, and exposure to disease.
DOUG SMITH: A littlebit of mange here.
This pack's beensuffering from that.
This is a two-year-old.
She bred this year– we think from fieldobservations– so its teats arelarger than normal.
PHIL KEOGHAN (VOICEOVER): Withthe birth of each new cub, or the death of an elder, the pack's numbers fluctuate, so Doug's team has to trackdown these collared wolves again in late winter.
That's what we're doing now.
But as I'm experiencingfirsthand, finding them is no simple task.
No signal, OK.
But I'm hearing the plane, sothat's probably our best bet.
Wait and see what they get.
Plane always gets them.
He's got an antenna strappedto the strut of the wing to track the wolves.
So when he gets them, he's going to call us.
That's right here.
So that big white slopeis where another pack is.
That's Upper Hill Roaring.
So we've got two packsstacked up right here.
So we're surrounded bywolves, but can't see any.
Welcome to wildlife biology.
[chuckles] All right, let's see if wecan help the crew find them.
[atmospheric music] DOUG SMITH: See if you seea bone or something exposed.
That's what we're looking for.
And you know what? That's ribs.
PHIL KEOGHAN: Yeah? DOUG SMITH: A dead elk.
PHIL KEOGHAN: He got eagle-ized.
DOUG SMITH: Youwant to pull it up? PHIL KEOGHAN: [grunts] DOUG SMITH: There you go.
PHIL KEOGHAN: Oh, wow.
The way these rib bones arebitten right off, that would be the work of a wolf? DOUG SMITH: Or coyote.
So this wouldhave been, how big? Oh, Jesus, this isa full-grown bull elk.
So we're talking– 750 pounds.
And this is all that'sleft, pretty much? Well, there's going tobe other bones in here.
I don't know if we'll find more.
PHIL KEOGHAN: Ah, there's alot of blood in there, look.
This is proof positivethat these wolves killed it, and it bled.
And it goes into the snow, and that is something we use as a tip that it was killed.
I guess we're alittle late to dinner.
DOUG SMITH: We are.
We're going to keep working.
PHIL KEOGHAN(VOICEOVER): Just when it seems we maynever encounter any of these reclusive predators– DOUG SMITH: Wait a second, Phil.
PHIL KEOGHAN(VOICEOVER): –Doug gets a tip from a fellow ranger.
And so what was her tip? It was just down the road here? DOUG SMITH: Yes.
In the middle of LamarValley, the pack of wolves is visible on a kill.
But we'll see if we can find it.
PHIL KEOGHAN: Sounds good.
Maybe on top of that mound.
DOUG SMITH: I'mtrying to get set up.
[foreboding music] There's only three wolves.
And I'm just trying tosee if I can get glimpses.
PHIL KEOGHAN: So we'relooking a mile and a half away to try to pickout a wolf that is pretty camouflaged out there.
[foreboding music] Damn, I'm not finding him.
PHIL KEOGHAN: SoDoug, this could be our last shot at this, huh? DOUG SMITH: It might be.
I mean, wait a second, Phil.
You should check this out.
[uplifting music] PHIL KEOGHAN: Oh, yeah, I got them.
Wow, that is amazing! DOUG SMITH: They'resingle file on a trail, classic wolf travel.
Looks like a scenttrail around, maybe.
A little bathroom break.
PHIL KEOGHAN: [chuckles] Wow, that is spectacular stuff.
They really are moving.
She's in deep snow now.
Changing the lead here.
I can't believe wepicked out two wolves maybe a mile and a half away.
DOUG SMITH: Yeah.
Now, there should be a third.
The third wolf in theirpack might be over there.
PHIL KEOGHAN: Whoa, hold on.
Is that a wolf? On the ridge! DOUG SMITH: Oh, yeah.
She's momma ofthat other female.
[howling] PHIL KEOGHAN: Oh my god.
You can hear it howling.
You know, there's threeways to experience a wolf.
You see it, yousee their tracks.
But hearing them howl is byfar the best of the three.
[howling] PHIL KEOGHAN: Whoa, there they go.
DOUG SMITH: Theypicked her howl up.
PHIL KEOGHAN: So they're headedover towards their momma now? Yeah.
They're looking for her.
Big part of wolf lifeis their social nature.
This is just extraordinary.
This is what we came for.
DOUG SMITH: Oh, yeah.
I mean, I can't believehow lucky you got.