An international team of explorers,
scientists and filmmakers is on a critical mission to save tigers.
THUNDER CLAPS
Revered and feared, the majestic tiger has been hunted to the brink of extinction.
But the mysterious Himalayan kingdom of Bhutan may hold new hope.
What we find out here could be essential for the survival of the species.
The expedition has found tigers in the tropical south.
Now, the search continues into the mountains, where science says tigers shouldn't exist.
We have to look everywhere.
We have to search everything. That's our mission.
As the team take on the mighty Himalayas, they will face their toughest challenges yet.
Predators enter camp.
We've got a cat! Gee! Oh, we've got a cat.
Oh! Food supplies are ruined.
I've suddenly become a vegetarian.
And they are stalked by big cats.
And I don't know where the hell I am.
What they discover in the mountains could change the fate of tigers forever.
Oh, my gosh! Oh, my gosh.
Bhutan is a little-known Himalayan country.
From its border with India, the land rises 7,000 metres into the highest mountain range on earth.
For three weeks, the expedition has been based in the tropical south.
Now they're packing up jungle base camp.
The final and most crucial phase of the expedition has begun.
A small team is travelling into the high Himalayas
to investigate rumours that tigers are living at extreme altitudes.
Gordon Buchanan is a wildlife cameraman, with 10 years' experience filming big cats.
He's returning to these mountains to check the camera traps he set at the start of the expedition.
All ready to go.
Good luck.
It's quite exciting because all this time that I've been at base camp,
the camera traps that I laid up in the Himalayas a good while back,
they've been clicking away and recording images up there.
With Gordon is Oxford University biologist Dr George McGavin.
He will be carrying out a health check of the forest, to see if it's rich enough to support big cats.
The cooler, higher altitude will have a completely different fauna.
Totally uncharted, unknown in terms of its animals and plants.
These mountains are the missing piece of a puzzle that might save tigers from extinction in the wild.
Tigers used to range across all of Asia.
Only small pockets remain.
But there is a master plan
to link isolated tiger populations in the last wild landscape along the foothills of the Himalayas.
No-one knows how many tigers there are in Bhutan.
The vast tiger corridor will only be effective if evidence of tigers can be found.
Not just in its southern jungles, but in the mountains, too.
Time is not on their side.
Tigers could go extinct over the next one or two decades.
Literally, tigers are dying as we speak.
The inspiration behind this master plan to save tigers is big cat expert Dr Alan Rabinowitz.
The Himalayan corridor, by its nature, by its name, is a very mountainous region.
Its survival will depend on whether or not
tigers can live and move through some of these high mountain ranges.
The team has just two weeks to find that vital evidence.
Gordon and George's new base camp is 3km higher than their last one.
With the help of local herders,
this expedition will be the first from the outside world to explore this remote region.
There are no roads here.
So the expedition's kit is arriving by pony train.
Gordon's prepared for anything. He's brought an arsenal of high-tech cameras.
If we're going to be successful up here, we have to throw everything we've got at it.
So we've got the thermal camera, we've got the infra-red camera,
we've got the big long lens and the camera traps.
Because for Alan's idea of the tiger corridor to work,
we not only have to find tigers down in the south, but we have to find tigers throughout Bhutan.
Explorer Steve Backshall is the third and final member of the mountain team.
He is five days' walk to the northeast of Gordon and George's mountain camp.
Steve's trekking up to the Tibetan border, to a remote peak where tigers are rumoured to roam.
Local people call it Gang Chen Ta - Tiger Mountain.
As far as knowledge of tigers go, this part of the Himalaya hasn't been explored by anybody.
So any information we can find up here is going to be massively valuable.
Steve has tracked deadly predators across every continent.
Now he's on the trail of tigers.
His field skills will help him discover whether legends of tigers
living at high altitude in the Himalayas are true.
Fact and fiction can become blurred at these extreme altitudes.
Just saw quite a large shape moving into these trees.
I'm not 100% sure what it is, so going to just move quite quietly.
Bhutan's mysterious mountains are supposed to be home to a huge hairy creature called the Yeti.
Oh, it's a yak.
There are some wild yak left in the Himalaya. There are not many.
Most of them are domesticated,
and just allowed to roam free and graze like this one here.
Yak usually occur too high to be tiger prey. I've never heard of it happening.
But it could.
A male tiger needs to eat close to Steve's body weight in fresh meat every week.
The best way to track down an elusive tiger is to first find its prey.
On this main track that we've been walking on,
all of the tracks that are left behind
are from the shod hooves of horses and donkeys.
This here, this kind of chute running down the hillside is very, very steep,
and it's not made by domestic animals.
This is definitely coming from wild animals.
So there you can see a very definite cloven hoof.
Slightly splayed because it's going uphill on a soft surface,
but that is from a sambar deer.
It's the largest deer found round here, and the favourite prey of the tiger.
So even though we haven't actually seen any of these animals yet they're definitely here,
and it's really, really good news for us because this is exactly the kind of large prey that tigers need.
I mean, they'd need to eat something the size of a sambar deer probably at least once a week.
Before it gets dark, Gordon and George head off to get a feel for the forest around camp.
BIRD CALLS
The altitude will make exploring here a physical challenge.
We've just moved from the tropical forest at low altitude up to 10,000 feet in an hour,
and you feel a bit breathless.
So, I'm not going to be racing about after insects for a day or two.
Well, a day.
George will perform a rapid health check of this forest by surveying the smaller animals that live here.
It's early spring, so it should be full of life.
Absolutely stunning.
FAINT PECKING
A woodpecker.
I reckon it will be very hard to see anything in this.
I reckon we'll have to have a lot of luck on our side.
Cos even if you're very careful, you make just too much noise.
TWIGS SNAP
Gordon's exploring the perimeter of camp.
Just off the track, a huge scat.
This is probably the kind of upper end of a leopard scat,
kind of lower end of a tiger scat. It could be either.
But it is definitely from a big cat.
And we are... Camp is just on the other side of the trees there.
200 yards away.
Wow.
I always think, where a cat walks once, it's likely to walk again.
Amazing that we've just arrived and we're finding signs of big cats right beside camp.
There's no way of telling if they're the droppings of a tiger or a leopard.
It's a promising lead for the expedition,
but signs of any big cat prowling so close is a serious worry for the herders.
They round up their animals and light fires.
One domestic animal like this would be an easy meal.
25 may tempt the predator even closer.
That's a very smart idea to have them all tied up to a rope here,
where they can have an eye on them,
than having them all around the edge here. Cos that's a risk.
And they are now very concerned about the thought that they might lose one of their animals.
Big cats usually avoid humans.
But hungry tigers and leopards WILL eat people.
They ambush their prey, ideally in the pitch dark.
Everyone must be on their guard.
If a big cat does prowl close to camp,
Gordon should spot it, using night vision or thermal imaging gear,
which picks up body heat.
After five cold hours, George sees something unfamiliar in the darkness.
I just walked out and I saw eyeshine on some animal over here, but it was moving in an odd way.
It was as if it was flying, but not.
It is 100% big cat.
It had a long tail.
The thermal camera picks up the ponies and a small hot-spot in the trees behind them.
Gordon's suspects it's a leopard.
But he needs confirmation.
Right, do you know what I'm going to do?
And I think I have to do this alone, is try and go up and intercept the leopard.
He's not going to come down. I'm not going to put him off.
But if I can go ahead of him, I might get some shots of him on this camera.
George will stay in camp with the thermal camera,
and warn Gordon if the leopard appears.
He looks very alone there. A little white figure.
(It's behind you!)
That's the dog there.
DOGS BARK
Dogs have seen someone or heard something.
It'll take more than a little dog like that to put a leopard off.
One of the favourite things that leopards like to eat are dogs.
I wonder, I wonder, I wonder.
You know, I'm convinced that that leopard is still there.
Gordon, there seems to be a very, very faint white spot
just up from you to your left.
Towards me or away from me?
If you spin round,
there's a very, very tiny white spot
just up the hill a bit. Over.
OK, Gordon the thing that I could see which is a white spot ran or moved very quickly
to the right and then back again to the left, and I think it was a smaller animal on a tree branch.
OK, I'm going to pull out of here.
I shall see you in a minute.
If it was a leopard Gordon saw, it seems to have moved off.
But he's barely back in camp when the herders' dogs
pick up something the team's high-tech cameras have not.
The ponies sense it, too.
Some have broken their tethers and have strayed close to the tree line.
There's a distinctive shape on the thermal camera.
We've got a cat. Gee. Oh, we've got...
a cat following one of the ponies.
It looks like a leopard. It looks like a leopard.
The ponies that we're using to help us with our equipment,
they just go off and they start foraging in the trees close by.
Unbelievable.
Unbelievable. It's still coming, it's still coming.
We are right in the middle of camp.
This is the first night here up in the mountains and we have a big cat.
Look at that.
Just absolutely bold as brass.
It's not as thick-set as a tiger.
You know, these cats living up here will not be that used to seeing horses,
and this one's just taking full advantage of it.
Oh, I've just lost him. No, I've lost it.
There's nowhere in the world that you can just show up,
drop out of a helicopter and see leopards. Nowhere.
Has this night been a one-off or are Bhutan's mountains a refuge for other rare cats?
Finding leopards at this altitude
is no guarantee that tigers also exist here.
Steve is trekking towards Tiger Mountain,
along paths made by generations of remote Himalayan tribes.
He's not finding the big prey he'd hoped for.
Just caught a flash of golden colour, and having taken a few minutes just to look around me,
I've seen that this hillside is absolutely covered with marmots.
Marmots are very good at taking care of themselves.
If one of them senses the presence of a predator, they'll let out a big alarm call like a whistle,
and all of them will just dive for burrows instantly.
Leopards will eat marmots, but they're probably too small to be tiger prey.
Ah, there they go.
Two males letting off steam.
Almost like all-in wrestlers with each other.
I guess because now is a time of plenty,
and marmots don't have to worry so much about laying down fat reserves and gathering stuff for hibernation,
they're just letting off steam.
It's hilarious to watch.
Gordon is heading for the top of the mountain
to check camera traps he set out at the very start of the expedition.
Thick bamboo and the punishing gradient reminds him how unlike classic tiger habitat this is.
Considering how much effort it takes me to walk round here, it's going to have an effect on the tigers.
At the moment, I just think...
it seems just ridiculous that they might even be here.
If it wasn't hard enough, the altitude, even at this height, really kicks in.
Going downhill's fine.
As soon as you start coming up, it really hits you.
And it's really steep here so you're having to work 10 times as hard.
Oh, gosh. I wonder how George is doing.
BRANCHES SNAP / HE YELLS
George is still finding his feet.
His 30 years of field experience will be invaluable in assessing
whether these forests really can support tigers.
This stump is just full of this stuff.
The wood's just rotten away. But what's interesting
is that I can see no signs of any insect there moving.
Which is sort of surprising. But...
there's plenty more stumps and plenty more rotten logs.
But no bugs.
Even in spring, temperatures drop below freezing most nights.
There are far fewer animals here than in the tropical forests the team's just left.
George will have to use every trick to find out what lives here.
Each discovery will be included in the scientific report he's compiling for the prime minister of Bhutan.
Oh! Look.
Wow.
These chicks have just hatched.
To find out what kind of birds they are,
George will have to wait for the adults to return.
OK, that's the female back, and she's got a beak full of earthworms.
My goodness, that's a lot of worms.
It's really great to be having a really good view of these chicks and actually see what they're being fed.
Which is the only way of finding out, to sit here and actually watch them.
Obviously those birds are a lot better at finding
earthworms and insects than I am.
But then I'm not a white-collared blackbird. There we are.
Gordon's approaching the camera traps he set at 5,000 metres.
At this altitude, it's too harsh, even for trees.
Can tigers really have adapted to such an extreme environment?
Gordon's camera traps may hold the answer.
They've been recording everything that moves past them.
First one.
Come on, please, we've got to get something.
We've got to get something.
Often the case is with camera traps you get every animal apart from the one that you're actually after.
Oh, look, is that choughs?
Yeah, these birds have set it off.
Actually, when I was up there, I saw the choughs flying about over that ridge.
OK, you can see what's triggered this.
Heavy snow. Even though it actually looks like rain.
Oh, fox! Wow!
Great. Red fox.
Oh, you're beautiful. Look at that.
Oh, it's posing perfectly for the camera as well.
Gosh, that is lovely.
They're the same red foxes that we get in the UK. They're amazing.
They really are amazing animals, the fact that they can make a living
from the dustbins outside our houses and they can make a living here, high up in the Himalayas.
Oh, what was that? What was that? What was that?
Jesus, is that a snow leopard?
You ratbag! It is!
Snow leopards are incredibly rare and elusive.
Oh, wow.
No wonder hardly anybody sees these cats, they're just so well camouflaged.
You could literally walk past that within four metres and not see it, easily.
It looks like it's a cub.
And the reason it's staying there for such a long time, I'm guessing,
is that its mother has left it there while she's gone off hunting.
Oh, wow.
That is just stunning.
Oh, it's come right up to the camera.
That is one of the most exquisite-looking animals I've ever seen.
Snow leopards are an exceptional find.
But maybe 5,000 metres is just too high for tigers.
Gordon decides to intensify his search lower down the mountain.
He's brought extra camera traps from the old base camp in the south
and sets them out across the mountain side, from the tree line at 4,000 metres...
right down to the bamboo forest near their new camp.
While Gordon's on the trail of majestic big cats, George has found something less appealing.
These are flesh flies.
There is an animal in here somewhere.
There is something...
There is something here that is not right.
BUZZING
Blow flies have found their way into the tent where the expedition's meat is stored.
If you don't have a refrigerator,
you have to eat dry meat or dry fish.
And that does attract a lot of flies.
There are more insects in this tent than I've found in the entire forest.
Mind you, it's only one species.
Look at that, in there.
That's fly eggs!
Within hours, these fly eggs will hatch into maggots.
I've suddenly become a vegetarian.
In the far north of Bhutan,
15 kilometres from the border with Tibet, Steve's almost in sight of Tiger Mountain,
where local legends say tigers roam.
This is probably our best chance of seeing things. We're just at the tree line
and, all around us, the hillsides are open.
So we can see for a long, long way.
Oh, hang on!
That's a huge herd of animals.
I mean, I reckon there's got to be 40 or 50 there.
They are called blue sheep because they have a kind of slatey blue-grey coat.
And there's...
I can see one adult male
with huge horns.
They're totally at home out here, in this steep-sided, barren land.
They're incredibly graceful and nimble over the rocks.
But if the tiger really is living in this sort of area, or anywhere near here,
that's what it's going to be feeding on. Blue sheep.
For an ambush predator like a snow leopard or a tiger, this is kind of easy game.
Large herds of blue sheep would be perfect prey for a tiger.
But science says tigers don't live at these heights.
Steve will need to find concrete evidence to prove the textbooks wrong.
The first step is to meet the people of Laya.
Hello, hello.
It's one of the highest villages in Bhutan and the gateway to Tiger Mountain.
If there are tigers living at 4,000 metres, surely the villagers will know?
This would have to be just about the most spectacular spot on earth to build a village.
The houses are just exquisite.
All of the wood is beautifully painted.
Journeys like this are all about auspicious signs in Buddhism, and you don't get much more auspicious than
that beautifully painted image of a tiger.
Tigers decorate every house.
Steve's keen to find out if they're imagery from local folklore or a picture of real life around here.
1,000 metres below, Gordon is trying everything to get hard evidence of tigers.
He's looking for a vantage point in the bamboo forest to set up a hide.
Whoa, look at this. It's all bare.
Lots of signs of signs of animals having used this area.
Wonder if they're sheltering.
The big rock overhang, here.
Oh, some dung here.
Oh, do you know what I think this is? Look.
I bet you it's a salt lick.
Let me just see.
Yeah.
It's very salty.
Deer and other plant-eating animals don't get enough salt in their diet.
Sooner or later, they have to visit salt licks.
Gordon hopes tiger prey will be drawn out of the forest and tigers won't be far behind.
All he has to do is sit in his hide and wait.
# At the back of my mind
# I was only hoping that I might just get back... #
Up in Laya Village, Steve has been invited to the home of a village elder and his family.
Kuzo zangpo la.
Oh, look at that.
I'm Steve. Yes.
Pleased to meet you.
HE SPEAKS HIS NATIVE LANGUAGE Kinle? Steve.
Kinle has spent his whole life in Laya, and will know about the animals found here.
Oh, wow.
Sit here?
Before Steve can ask any questions, his hosts prepare him a medicinal drink.
It's supposed to give him strength for his onward journey.
Oh, wow, look at that.
This is the famous Cordyceps fungus.
It is essentially a fungus growing out of a caterpillar.
How anyone came up with the idea that this could actually become
a sort of panacea, a medicine that could cure all ills,
is totally beyond me.
But it does have to be one of THE great, weird,
grotesque miracles of nature.
You can still see the almost intact, if somewhat desiccated,
body of the moth caterpillar.
This is its head up here. And the fungus,
the fruiting body of the fungus, has erupted clean out of the head.
That is just bizarre.
Right. So she's just put one of the caterpillar in with some of this distilled wheat liquor.
And then drink? SHE SPEAKS HER NATIVE LANGUAGE
And it's good for stomach? Yeah? OK.
Right, if I actually drank all of this, forget about the caterpillar,
I would not only be hanging drunk but I think very, very sick, particularly at this altitude.
So I've just got to figure out how much I can take and be polite.
Oh, dear.
CROAKILY: That's good!
THEY LAUGH
HE COUGHS AND SPLUTTERS
Yeah, it's good. I'd like to say I can feel it working,
but I'm sure that's just the booze.
But it's Gordon who needs the hit.
The last six hours at the salt lick have passed very slowly indeed.
Oh, what's that?
Nothing.
There's nothing.
This is so time-consuming, just sitting here, waiting.
Waiting, waiting, waiting.
You just feel a bit silly,
sitting in a hide, waiting,
in the hope that a tiger's just going to amble past
in the short time that I have to spend in here.
That's the great thing about the camera traps,
you just put them in and leave them.
You put ten camera traps out and they can stay there 24 hours a day,
daytime, night-time,
functioning, always watching, always ready.
Unlike me in a hide.
George has discovered some curious holes near camp and he's gone to investigate.
Put that in there.
Woo-hoo, nice.
Right, let's see what we've got in here.
A voyage into the darkness.
HE HUMS THE THEME FROM THE A-TEAM
Clearly been used.
It's quite clean.
That is definitely working.
(Ah! It's a pika.
(They're very similar to rabbits and hares.
(Look at it.
(Let's see if I can get closer to it.
(I think he might be getting a little bit annoyed about the fact that I'm trampling across his burrow system.
(This is just... I never thought I'd get this close to a pika.)
HE CHUCKLES
(I'm going!
(I've heard they like flowers as a bit of a treat.)
George wants to tempt a pika even closer.
(I could have touched it.
(Oh, my God.
(It's eating the white ones.
(I don't believe it!
(Look.
(I'm actually...) HE LAUGHS
George is discovering this mountain habitat is far richer than it first appeared.
It's a case of knowing where to look.
(This is very difficult.
(This whole bank has been burrowed away, it's very soft. Oh!
(Oh!
(Ah! Oh, my God.)
In Laya, Steve's welcoming ceremony is over.
He can start asking direct questions.
HE SPEAKS HIS NATIVE LANGUAGE
Kinle is a farmer. This is kind of ideal for us, because to find someone who does travel right across
the full range of altitudes here, he could have really good handle
on what's going on with the big cats here.
Kinle, what wildlife, what animals do you see here?
HE SPEAKS HIS NATIVE LANGUAGE
The first things he said he sees as far as wildlife goes were things you'd expect.
Then, he said he also sees tiger. Sometimes they'll see the footprints, the pugmarks in the snow.
And also the carcasses of animals that have been killed by tiger.
How big would you say a tiger footprint would be normally?
HE SPEAKS HIS NATIVE LANGUAGE
I completely assumed that Tiger Mountain was a name purely out of mythology.
But Kinle is telling me, the reason it got this name is because there are tigers there.
If that's true, then that's a really big deal.
Because the base of Tiger Mountain is well above the tree line
and much higher than tigers are actually thought to ever go.
Any real evidence we can find that this is true is a major, major discovery.
Steve has his first real lead that tigers might be living up here.
To check out these stories, he will leave Laya and continue on towards Tiger Mountain.
Kinle will set him off on his journey.
These are prayer wheels. You see them very often in Buddhist culture. And you have to spin them clockwise.
It's auspicious, particularly for a journey.
Oh, there's a big one. Yes, yeah.
BELL RINGS
If Tiger Mountain is home to a secret population of tigers,
living at over 4,000 metres, it won't just be exciting new science.
It would prove that tigers live throughout Bhutan.
The country could become a heartland within the proposed tiger corridor,
from which they could spread out and repopulate the whole region.
In the bamboo forest near camp, Gordon has given up on the hide.
He's keen to see if the camera traps have had more luck.
This one's here, still here, which is good.
Oh, come on. Please, please, please.
Undetected, the remote cameras have been quietly
filming everything that moves past them in this secret forest.
A rare golden cat that almost nothing is known about in the wild.
A bizarre-looking serow.
Herds of takin on their summer migration to high alpine pastures.
Langur monkeys.
A rare glimpse of the shy red panda.
Huge Himalayan black bears.
And, most amazing of all, a leopard, scent-marking its territory.
Probably the same cat that stalked through camp on the first night.
I'm absolutely astounded by the numbers of animals living here,
compared to what we're seeing.
And these little camera traps, they're giving us a little kind of peek through a keyhole
into a very rich environment, a place that is more than capable of supporting tigers.
Come on, just once, I don't even want a whole tiger.
I just want a tail.
A stripe. An ear. Just something to tell me that tigers are here.
Time is running out.
Steve has finally reached the foot of Tiger Mountain.
This is where the Layap tribe say they have seen tigers.
We've been going for six days now and we're coming right up to the northernmost extreme of Bhutan.
Up there is Tiger Mountain, and there's some of the wildest,
most beautiful country you'll see anywhere in the world.
The thing is that, even though we're at 4,300 metres, there's still cover, there still is trees here.
I really didn't think that we'd have tiger anything like this kind of height, but it is possible.
There's enough cover for them, there's potentially prey for them. I don't know.
Maybe the stories the locals were telling are true.
That's a lammergeier. They're just massive, absolutely huge.
These birds have sighted a carcass of some kind up there,
and that really would be very, very exciting because anywhere you find a carcass, you're going to find
other kinds of scavengers and perhaps even predators. This is fantastic.
If the animal carcass is fresh, then the vultures may lead Steve to the predator that's still feeding on it.
Up here, it can only be a big cat.
Steve follows the vultures. They're circling close to a small stone hut,
home to a family of yak herders.
The father is worried for the safety of his small children.
A wild blue sheep has been killed a few hundred metres behind their hut.
THEY SPEAK THEIR NATIVE LANGUAGE
Could you show me where this happened and maybe if there is any sign there?
TRANSLATOR SPEAKS
HE SPEAKS HIS NATIVE LANGUAGE
TRANSLATOR: He's going to show us the spot.
OK.
The kill site will hold clues as to what happened.
Oh, wow!
OK.
This is all rather unpleasant, very, very strong smell.
It's still, from the waist up, very much intact.
It's just eaten the back half, and most of the rest of it is gone.
The herder has found paw prints close to the carcass,
but they're not big enough to be the tiger Steve was hoping for.
They belong to something equally elusive.
Ah, yes.
He sees here
the pugmarks
of the snow leopard, going this way.
I see, yes, I see.
Oh, yes, I do see.
Perfect.
Those are the toes there.
That's the pad print, toe, toe, toe and toe.
She's moved up this gully, around like that, and off in that direction,
and she probably used this ridge line here to actually hide herself.
We have a great chance here, probably the best I'll ever have in my life,
of actually seeing and filming a snow leopard.
And I think that chance is just to sit and wait up there, and see if it comes back for the remains.
To avoid spooking the cat, Steve must be alone.
That's the blue sheep that was killed last night.
I've put myself in
under a rocky overhang
so that my back's protected and nothing can come at me from behind.
Can't pretend I'm not scared.
I am.
Venturing out at night is risky.
But George and Gordon know it's the best time to find evidence of big cats.
It's so thick in there.
Just using this spotlight to just see if can pick up any eye-shine.
George has spotted a pair of eyes reflected in his spotlight.
Gordon's night-vision camera will give them a better look.
You see the eye-shine there, just in that fork.
OK, moment of truth, George.
Oh, what the...
It must be a squirrel.
Kind of hard to tell.
Yeah, definitely a squirrel. Ahh.
Maybe a flying squirrel.
Now that is a flying squirrel, see the flaps.
Oh, look at that, oh, yes.
You beauty, you going to do a little flight for us? Oh, that's amazing.
See this is one creature that probably wouldn't have much trouble in this forest.
Imagine just being able to glide from one end of the valley to the next.
Bit of evolution.
If I could see him flying, that would be just amazing.
Gordon continues on, but George is determined to see a squirrel fly.
The best way is with his thermal-imaging camera.
Is it going to do anything, I wonder?
Wow! I don't believe it!
That's gone straight off the screen!
That was about 70 metres! That's unbelievable.
Wow! Look at that!
That was an absolutely enormous leap.
Just by having two flaps of skin from the legs, acting as a sort of umbrella, if you like.
Flying squirrels can stay in the safety of the trees.
With large predators about,
the ground is the most dangerous place to be.
On the slopes of Tiger Mountain, the cold has forced Steve to abandon
his stakeout, but he's lost his way back to the tents.
I suddenly feel very exposed, out here on my own.
If a snow leopard can take down a yak,
then it certainly wouldn't struggle with me.
And I don't know where the hell I am.
DISTANT BARKING
I don't know if you can hear that, but the yak herder's dog
is going absolutely mental, just non-stop barking off in the distance.
That could well be cos he can hear something.
Steve is definitely not alone.
A line of prints here.
Snow leopards, despite being very powerful animals, move very lightly on their feet.
This print is still settling,
is still filling with water, you can still
see it moving around.
This is really fresh. She was here
maybe just a minute or two ago.
She could be watching me right now.
I've spun myself around now.
No idea where I am.
That's where I've just come from.
There's eye-shine dead ahead of me.
Oh, there's two.
No, that can't be right.
Aww! I just gave myself a fright there.
It's the yaks.
Oh, is that...? Oh, that's our toilet tent.
Oh, thank God for that.
Next morning, Steve wants to find out
if last night's encounter
with a snow leopard
was as close as it felt.
So, he came in down here,
and you can see here
really clearly
the exact marks where he's accelerated away.
Some more here, and they're all scraping away as he sprinted off up in this direction.
Again, really clear ones here.
And then he's gone.
So, I was five metres away from a wild snow leopard.
I mean, look how close he was to me.
Despite his close encounter, Steve must leave Tiger Mountain
without cast-iron proof that tigers live up here.
Gang Chen Ta has held on to its mysteries.
George is returning to the capital to present the expedition's findings to the Prime Minister.
The teams still lacks scientific evidence of tigers living at altitude,
even though the forest looks like it could support them.
Wow, look at that pool. That is spectacular.
I've seen some beautiful places in my time,
but I don't think I've ever seen anywhere on earth that rivals this.
A picture just can't grab this.
It's primeval.
Soaking it up, because I might not be back.
What we're going to do is just hang onto as much of this as we can.
For the largest surviving cat in the world, and one so beautiful...
..Bhutan seems to be its last hope.
Because everywhere else, it's hunted and poached and killed
for skin, for parts, for cures of various sorts.
The thought that tigers could be gone
in 50 years...
..is, um...
It's just unthinkable.
Just one image would prove they live up here
and could help secure their future.
Gordon's camera traps are the team's last hope.
Oh, look at this bear.
Oh, sniffing the camera.
The camera traps aren't always invisible.
He's a really healthy specimen as well.
He'd have to be living up here, it's going to get cold.
He's going to have to work hard. It's only the strong that survive.
Oh, my gosh! Oh, my gosh!
Oh, oh, I don't believe it!
Oh, God, oh!
Thank you, thank you, thank you!
Oh, gosh!
OK, they're here.
HE SOBS WITH EMOTION
You know, it's only one tiger, but the fact that they can live here
is just so important, not just for this one individual,
but for tigers in the wild for the future.
It's just... Oh.
Oh, man.
It just walked along this path,
literally down this path.
If he was just passing through this area, he would have his head down just powering on through.
But he's scent-marking quite high up on the rock
and what he's saying is, "This is my place, this is where I live."
Finding tigers here is phenomenal, because what it does -
it just shows that almost every square mile from here down to India is potential tiger habitat.
Gordon has found tigers at 3,000m and he still has more cameras to check
a vertical kilometre higher up the mountain.
How high into the Himalayas are tigers living?
45 images.
I wonder what that's of.
Oh!
Oh, man alive!
I'm just completely speechless.
Gordon's cameras have captured over 30 images of tigers walking along this ridge.
These tigers are living right in the shadow of the high Himalayas.
We are above 4,000 metres at this point.
These are the highest-living tigers in the world.
There are at least two adult tigers here -
one male, one female.
You've got one tiger that's walked through here, scent-marked on that rock.
A second tiger...
big male, comes through in the day, stops, sniffs.
We're watching possibly the precursor to tigers meeting and mating.
There's a female up here letting the male know that she's around.
They've probably met and mated by now,
and somewhere I really believe there is a little cave
down in one of these valleys that have tiger cubs in it.
Tigers breeding this high in the Himalayas is totally new to science.
More importantly, these animals could be central to the tigers' survival.
If Bhutan stays the way that it is, it just becomes a big machine that produces tigers that will move out.
It is incredible, just blows me away.
The expedition is coming to an end.
But George still has one last important visit to make.
He's presenting the team's findings to the Bhutanese Prime Minister.
The report shows that the ancient Kingdom of Bhutan
holds a significant proportion of the world's wild tigers.
It will be the heart of the tiger corridor if governments across the region can work together.
There is our brief preliminary report...
Thank you very much.
This should be very, very useful.
Tigers must be protected.
Tiger doesn't belong to us, to this generation alone.
It belongs to future generations as well.
Alan's plan to link isolated tiger populations
and create the world's largest tiger reserve is closer to reality.
This gives me hope.
This area holds the key
for the future of tigers,
hopefully, for the whole Himalayan corridor, and could serve as a model for the rest of the world.
The tiger corridor had a big missing link in it, and Bhutan was that.
Nothing was known about the tigers that may live here.
We have filled in the final part of the puzzle.
People have pushed tigers to the brink of extinction.
This is their last chance.
Can we save tigers? Absolutely we can save tigers.
We will save tigers.
Subtitles by Red Bee Media Ltd