Lost Land of the Tiger (2010) s01e02 Episode Script
Episode 2
One of the most remarkable animals ever to have walked the earth is heading for extinction.
Now, an international team of scientists, filmmakers and explorers has been given unique access to the remote Himalayan kingdom of Bhutan.
If they can find a thriving population of tigers here, there's a chance to bring them back from the brink.
It's perfect tiger habitat.
But it won't be easy.
If a snow leopard can take down a yak, it certainly wouldn't struggle with me.
It can't get any worse that this.
THUNDER CRASHES Woo-hoo! They're taking on the wildest Himalayan rivers .
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fighting through the deepest jungles .
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and scaling the highest peaks.
My lungs are burning.
My legs are burning.
Do I really want to do this? What they discover could be the key to saving this magnificent big cat.
Can we save tigers? Absolutely we can save tigers.
We will save tigers.
Hidden in the foothills of the world's highest mountain range, lies the little known Kingdom of Bhutan.
These Himalayan forests could be the tiger's last hope for survival in the wild.
An expedition has set up camp on the banks of a river in the south of the country.
A hand-picked team has already spent 10 days searching for tigers.
They now have hard evidence these elusive cats are living close to base camp.
For this phase of the expedition, they will be spreading the net wider.
On his way to help them, is wildlife cameraman, Gordon Buchanan.
He's spent 10 years filming big cats worldwide.
It's amazing that we are looking out at what could be the future for tigers in the wild.
The only chance that they've got are them existing in hills like this.
He's already placed remote cameras high in the Himalayas, to try to capture images of tigers living at altitude.
Now, Gordon's joining forces with Doctor Alan Rabinowitz, one of the world's foremost tiger experts.
Alan has dedicated his life to saving tigers.
I'm not sure tigers will be able to survive.
I wake up wondering if there's any hope for the tiger.
If we continue on the course we are now, tigers will be extinct in the wild easily within a couple of decades.
With Gordon in camp, the team's reunited.
They've worked together around the world.
But this is their most critical mission so far.
They have just 10 days left here.
Alan gets Gordon straight up to speed with the images they've recorded close to camp.
Oh! Oh, my word.
Oh, gosh, they're beautiful.
There's no other animal like them.
And it walks that way.
It walks like, "nothing bothers me, I don't have to be afraid of anything in this forest".
It just walks that way! It's a promising start.
But now, the expedition needs more detailed information.
What I need you to do now is to get me more pieces of the puzzle.
How many more tigers are there in this area? How far in the river valleys are they heading up? For Bhutan to offer tigers a lifeline, Alan needs to know whether there's a continuous population, right across the country.
He's sent naturalist and expert tracker Steve Backshall up-river, far to the east.
The Drangme Chhu is the biggest river in Bhutan.
It actually starts way up in the high Himalaya.
It flows right across eastern Bhutan.
There are no records at all about tiger numbers in eastern Bhutan.
Nobody knows anything about them here.
If we could find any evidence at all of tigers here, that's vital information.
Through this rugged landscape, river valleys are natural highways for wildlife.
They are the best place to search for tigers.
Steve's journey will begin at the top of the Drangme Chhu.
He'll travel downstream, scouring the riverbanks for tiger tracks right the way back to base camp, 100 kilometres away.
That's where the proper mission begins.
As this river snakes away from the path that we've been walking on, it heads into some of the most unknown territory in Bhutan.
Down there is where we're really going to find some answers about the tiger and the future of the tiger in Bhutan.
Answers need to be found, and quickly.
Virtually nothing is known about Bhutan's vast forests, but we do know that elsewhere, tigers are in deep trouble.
In the last century, the world has lost 98% of its tigers.
Only small pockets survive.
There could be as few as 3,000 left in the wild.
But all hope is not lost.
Along the foothills of the Himalayas, where human pressure is not so intense, Alan has a plan to join together fragmented tiger populations and give them the space they need to roam.
It's an idea he's been working on for many years.
The solution I have for saving tigers is to connect these isolated populations through linkages in the landscape.
So that some of these tigers could move between isolated fragments and thus the isolated fragments become part of a larger whole.
Bhutan is the missing link.
In India, the more isolated tiger populations have become, the quicker they are dying out.
Even those living in protected reserves.
Oxford University biologist, Doctor George McGavin, is heading south to India, to find out why.
It will be a very different experience from the forests of Bhutan.
It's really only when you're up here, that you realise just how vast the forest is, and, you know, how many tigers are roaming down there, I wonder.
That's what Gordon wants to find out.
But to estimate the density of tigers in the forest around base camp, he must draw on all his field experience.
All along here is exactly where I'd expect to find tigers.
That sort of lush, green grass that's growing here, creatures like Sambar deer will come out and feed here at night time.
And tigers will come out and check if there's anything there for them to eat.
Each tiger hunts over a huge area.
So Gordon's decided his best chance is to blitz the forest with 30 remote cameras, which can record day and night.
What we're trying to do is figure out how many tigers are in this area, because it'll give us an overall indication of the health of the tiger population in this part of Bhutan.
So we need to distinguish one from the other and the best way of doing that is the stripe pattern on each side.
They have a unique, almost fingerprint pattern that their stripes make up, so if we can photograph as many tigers as possible, we should be able to tell one from another.
Far to the east, Steve's 10-day descent of the Drangme Chhu is about to begin.
Dave Allardice will lead three rafts carrying the expedition's food and filming gear.
He's navigated the biggest Himalayan rivers, and knows their dangers.
We're going to be very careful out there.
The water's running high, you can see it's snow melt.
There's quite a lot of water, so we'll have to be careful.
It's hard telling what's down there.
Yeah, I guess that's the thing - we're kind of paddling off into the unknown.
The team's found a calm spot to launch, but once they start, there's no escape from this steep-sided gorge.
The nerves are going just a little bit.
Also really, really optimistic about our chances of finding evidence of tigers moving through here.
And that's our big goal, really.
Steve and three other kayakers will scout each set of rapids to pick a safe route through for the rafts.
With the river running so high, there'll be no margin for error.
Near base camp, Gordon's setting camera traps.
They won't trigger unless an animal walks within a few metres.
Gordon now needs to think like a tiger.
Let me just go up here.
I am a tiger.
I am a tiger.
I am a tiger.
Oh, no.
I'm thinking about food.
I'm thinking about going to a place where I can get something to eat.
I think I'll cross here, because it's just a little leap like this.
And I would go this side of the rock.
Maybe just right here.
Tigers aren't the only wildlife the team's looking for.
Bhutan's forests remain largely unexplored, so the expedition is compiling a report of all the animals that live here.
Wildlife camera woman, Justine Evans, is walking the forest trails to see what creatures she can find.
It's a huge forest, and I think it's just a tough place to work, you know? It's a tough place to get shots.
Especially now when there's a lot of rain, there's a lot of food about, it's going to be a really difficult thing.
Off we go.
Alan will stay in camp to analyse camera trap images as they come in.
The amount of tiger prey gives him a picture of how many tigers this forest might support.
These camera traps, these are our eyes in the jungle.
So far, the tiger prey that we're getting in the camera traps - the Sambar deer and the gaur, they look beautiful.
But the team really wants to find tigers here.
And right across Bhutan.
Steve is in the east, on the wild, upper reaches of the Drangme Chhu.
It's so rugged, so remote.
You can see why nobody's ever penetrated into this place before.
I mean, you could never get down these canyon walls, and it's just an absolute haven for wildlife.
And hopefully, one of those will be our tiger.
Their search has been made much harder.
The Monsoon rains have arrived early.
The river is high and the rapids are now treacherous.
I've got a big rapid to the left.
Stop! I'm going to stay away from them.
Come on! Come on! Right now, tigers are the last thing on their minds.
Keep paddling! Hard right! Keep going.
Forward together again.
Come on! Keep right of that one.
Safely through the rapids, they look for a place to stop.
Sandy beaches are where Steve hopes to find tiger footprints.
But the rains have made his mission doubly difficult.
You can see all of this rain just spatters off the surface and makes all the prints totally indistinct.
Everything around me now, I mean, there's lots of animal prints here, I have no idea what any of them are.
Some of them could have been left yesterday.
It just makes our job almost impossible.
We need to find a tiger track that's been left within the last hour, that's the only way we're going to succeed.
The team press on.
They will explore every beach they come across.
100 kilometres down-river, Gordon's been dogged by rain too.
But his search is proving more productive.
Come and see this.
Nice.
Very nice.
These are the tracks of either a very small tiger or a leopard.
These are just ultra fresh.
Look at that - it's just literally just been made.
These are the first big cat tracks that I've found.
Oh, that's good.
Man, I was beginning to worry, because there's almost nothing coming up this river bed, not even Sambar deer, nothing.
And then to find this, is all the encouragement that I need to maybe put some remote cameras.
We've got a big cat right here.
Only if Gordon gets a picture of it can they tell whether it's a different tiger, or one they've already seen.
A thousand kilometres away, in India, George is travelling to Bandhavgarh Tiger Reserve to find out why every single tiger has become so precious.
HORN BEEPS Very loud horn for such a small scooter.
India used to have lots of tigers and they were all over the place, and now they're just clinging on to small, isolated reserves.
And they're surrounded by a sea of humanity and I don't really see how tigers will be able to survive in the long term, when they haven't got anywhere to go.
As the population of the Indian subcontinent has exploded, tigers have been pushed out of their former habitat.
Numerous protective reserves have been created, but tigers are now confined to far smaller ranges than they need.
There are 27 tigers in this core, which is about 100 kilometres square.
Which is the range of one male tiger in the wild.
There's not enough space within the park boundaries.
Inevitably, tigers wander outside, and into direct conflict with humans.
Local tiger expert, Digpal, has been battling with this problem for over 10 years.
What are the risks for a tiger, individual, if it has to go outside, if it's pushed out? They start killing cattle or buffalos, or whatever they get.
So the maximum risk is the villagers.
They poison the carcass, and that's where the poachers can also go.
So a very high risk outside? Very high risk, yes.
Tigers feed on a kill for several days.
If they prey on cattle outside the reserve, angry villagers poison the carcass.
When the tiger returns, it is doomed.
It's a world away from the unbroken forests of Bhutan.
Gordon is heading back to camp, to do a first check of his remote cameras.
One or two casualties, most of them intact.
That's how they're supposed to look.
This is how they look once an elephant has got hold of them.
HE LAUGHS Do you know what? I can probably repair that.
But just how good has Gordon been at second-guessing the tigers? Oh, my gosh! Wow, look at that.
Another one, another one.
Gordon's struck gold.
Images like this of tigers is precisely what we need.
Just look at that.
They are such amazing animals.
You know, if ever there was an animal on this planet worth saving, it has to be the tiger.
Gordon has four images, but they may all be the same animal.
He'll have to leave his remote cameras recording until the end of the expedition, and then compare all the images to see how many different tigers are living here.
In India, where tigers are trapped in small areas, George can easily see them with his own eyes.
Look there, look at it! Oh, my God.
Oh, look at that.
And there are two cubs.
There's an adult tiger, about 100 yards from the car.
So that is a female with her two cubs, who are about a year old.
Oh! They are beautiful, beautiful animals.
Oh, look at that.
They're practising their stalking.
Look at that.
That is so beautiful.
It seems slightly unreal, actually, I have to say.
I mean, seeing a tiger this close in Bhutan would be just unthinkable.
I mean, it would never, ever happen.
It's a privilege to view.
But these young tigers face an uncertain future.
When that male cub reaches a certain age, he'll have to move on.
And it's not clear what he would do.
He can't certainly occupy the same range as the other males in the park, so he'll have to go.
It's unlikely he'll get far beyond the park boundaries.
Even tigers within reserves are no longer safe from poachers, who supply the Chinese medicine market with tiger bones and body parts.
Even in the isolated populations, where the big cats still survive, they're under great threat.
They're being killed there as well.
But if we save tigers within the last remaining isolated populations, we still have a problem.
Because the long term survival of just an isolated population is in grave doubt.
To avoid genetic inbreeding, male tigers need to roam over vast distances to find new females.
Space is what Bhutan's forests could offer tigers along the Himalayas.
This is just incredible.
This fog forms over the top of the water, it almost looks like the river's on fire.
Oh, it's a cave.
It's a waterfall.
I'll bet this is home to thousands and thousands of bats.
While the rafting team makes camp for the night, Steve hunts for signs of tigers.
OK, this is going to seem like the most tenuous bit of tracking out there, but I have been asked to record every one of the tracks that fits a tiger profile, no matter how degraded.
These tracks, well, they're going in that direction, but that's the first one I spotted.
They're coming back down here .
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and this one, I think, is the clearest.
It's very circular, seems to be heading in this direction and these look much more like toes to me than they do hooves.
The next thing really is just the size of it.
That is the perfect size .
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for a tiger track.
There's no way you could say this was evidence, but Alan will be able to tell better than I can.
So I'm just going to take this data back, and hopefully he'll tell us more.
In India, George has spotted a fully grown adult male.
There he is.
Oh, God.
Look.
Look at him! Absolutely magnificent.
Look at him, look at him.
Ah, look at that.
Look at that.
What a magnificent beast.
It's the most incredible animal.
I'm hooked.
I'm hooked now.
TIGER ROARS Wow.
It's the first time I've heard a tiger roaring like that.
ROARING That noise is just amazing.
Pretty emotional, actually.
I feel very emotional.
I'm a bit shaky, actually, after that.
Seeing them now so close, it brings it home to me even more what a tragedy it would be if these animals were to ever become extinct.
The hope is that we can help the tiger, which is a very adaptable animal, to increase.
And, you know, it's not hard to do.
It requires prey, it needs space.
We've just got to stop hunting and poisoning and poaching and allow the animal to move freely.
In reality, what you want is a massive area through which you can roam.
Currently, all you've got is little fragments of original tiger habitat which hold a few individuals, and that won't work for very long.
We need to join these up and I now see how it'll work.
If you can join these areas up and tigers are able to move freely.
With so many people living in India, there is little chance of linking tiger reserves.
Along the less densely inhabited Himalayas, carefully managed land within a conservation corridor would offer tigers safe passage between isolated populations.
Creating one giant refuge in which they can roam and breed.
ALAN: The tiger corridor is an ambitious plan, but it's a very, very doable plan.
It's become Alan's life's work.
Nine years ago, he was diagnosed with incurable leukaemia.
There's not enough time for me.
I've got to spend whatever time I have left making sure that this tiger corridor becomes a reality.
Making sure that tigers are saved for the future.
I think about It's really interesting, because I try not to think about my leukaemia, and yet it's in my mind every single day.
It's in the back of my mind every waking hour, because it drives me now.
It drives me to keep on doing what I know I do best, right up until I can no longer do it.
The rest of the team is inspired to work day and night.
Justine's trying a new tactic, to learn more about what lives alongside the big cats here.
So what I'm doing now is I'm going to walk some of the trails at night.
With these elephants.
So I can conceal myself behind them, but also, their smell is quite domineering, so hopefully it will disguise my smell.
These are all just ideas I have and they may work.
If we cover enough distance, we've got a good chance of seeing some things.
And it's just nice to be out walking in the forest and not sitting and waiting.
I feel a bit more proactive.
Deep in the forest, Gordon's remote cameras are a secret window into this world .
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revealing behaviour which would never otherwise be seen.
A sambar deer stomps his forelegs nervously.
He's being stalked by wild dogs .
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ruthless predators who hunt in packs.
A wild boar investigates the camera, unaware of the shining eyes of a leopard just a few metres behind him.
And the ultimate reward - a tiger, out hunting.
The remote cameras free up Gordon to stalk the forest trails himself.
This time of day is when tigers, leopards start to prowl about, actually probably half an hour ago, so I am walking along here half expecting to bump into a big cat.
Most of the time, kills take place at night time, so that's why tigers start to get active round about now.
Heavens above.
Oh, two.
Two porcupines.
There's no mistaking what these creatures are.
There's nothing in this forest you could confuse them for.
I've actually seen a tiger with a porcupine quill stuck in its throat, so even something as prickly as this is still a meal for a tiger.
Camouflaged by the elephant's smell and sound, Justine is hoping that the wildlife won't noticed she's there.
Going around with these elephants is the opposite of being stealthy and quiet.
It's the opposite really of being a predator or being a tiger.
I think it's probably a good thing for prey animals because we don't seem like a threat to them.
We're not trying to stalk them or trying to be quiet, and they probably just think we're a herd of elephants.
Her thermal imaging camera picks up an animal's body heat and makes them easy to spot in the dark.
I've got something here.
Looks like a squirrel.
It should be climbing up.
It's going way up.
Wow, what was that? It's a flying squirrel! It just went flying through the frame.
I didn't realise there were flying squirrels here.
That's a great find.
Far to the east, Steve is searching the banks of the river.
It's a little bit nerve-racking wandering through this tall grass at night, knowing that this could be tiger territory and we could actually be being watched by a tiger right now.
This is by far the biggest spider I've seen in this part of the world, and it is absolutely furious.
Look at it reared up.
That's wonderful.
This is a primitive spider.
All over the world, they're known as tarantulas.
Big, hairy spiders, they're heavy-bodied with downward pointing fangs and he's bound to have small venom glands at the top here, and a bite from this would certainly really, really hurt.
Look how angry he is.
He's actually got just hanging from one fang the wing from, I don't know could be a termite.
That is absolutely remarkable.
Justine's tactics with the elephants are working.
Very bright eye-shine.
It's quite thick foliage in here.
Just see if I can get closer to whatever's in here.
It's quite hard to work out what it is exactly, cos it's all curled up having a snooze.
But it looks very much like a civet to me.
It's actually waking up now.
Preening his tail.
Oh, you can see the head much better now.
Big yawn.
It's definitely a civet.
He's having a good old lick on his paw now.
Beautiful.
He's probably going to be busy all night and then sleep all day.
Ah, look he's moving, he's moving.
That's really nice.
It's great on the thermal camera.
You can really see the shape.
Jump! He's going to jump again.
There he goes.
That was great.
Gordon has found another pair of eyes reflected in his torchlight.
Where are you? Oh! There he is, there he is.
Oh, you beautiful little cat.
He's been looking for the largest cat, but has found the smallest, a leopard cat.
Wow, he's tiny.
Is that a youngster? I wonder.
Yes.
Oh, this is what it is about.
He's on the move now.
He's kind of same size as a domestic cat, much longer legs, spotted like a leopard.
Beautiful.
You know these leopard cats, they'll catch small rodents, birds even.
Eating grass at the moment.
Whether it's a cat of this size or whether it's a cat the size of a tiger, there's just no denying them.
They're just perfect, they really are.
Steve's search for footprints has been frustrated by heavy rain so he's switched tack.
Along the river, there's a handful of communities, rarely visited by outsiders.
Steve will try to gather local intelligence about whether they've seen tigers.
So we have someone.
When was it that you saw this tiger and where? HE SPEAKS NATIVE LANGUAGE OK, this young man has seen a tiger just up here, down by the river, two weeks ago which is pretty incredible.
And where was it? HE SPEAKS NATIVE LANGUAGE So, he saw the tiger.
It was in the forest in the middle of the daytime, about 3 o'clock in the afternoon and it saw him and began to move away from him and this guy shouted at it and it ran off.
So So do you and your friends and you family see tigers often, many times, or is this a very unusual thing for you? HE SPEAKS NATIVE LANGUAGE Um, yeah, this is really quite striking news.
So he wasn't on his own, there was three of them there - his father and someone else as well - so it's not like he's just kind of making it up, and also when I asked how often they see tigers, he said maybe once a month, sometimes every two months.
That is absolutely extraordinary.
There must be a phenomenal amount of tigers moving through here for there to be any sightings at all, let alone regular sightings.
Last thing that Alan said to me before I left base camp was that if you get any evidence from people who live round here that there are tigers here - even just one person saying that they've seen one - then that's going to be massive, and you don't get any more definitive than that.
Heartened by success, Steve continues on towards base camp.
Back in camp, Alan is marking all confirmed tiger sightings on a map.
Expedition biologist Rebecca Pradan has spent many years trekking through western Bhutan, where she's seen tigers with her own eyes.
And when I saw that tiger, I was just pinching myself.
Weren't you scared? No, it's quite a little bit far away, so then after some time, there's two things climb up.
It's a little bit like a dog little bit smaller than a dog size cubs.
Both cubs were there.
So it was a female and two cubs? That's terrific.
You've had more close tiger encounters than I have ever had.
That's incredible.
All of the data is now coming together.
The fact that Rebecca has walked so much of Bhutan and has had first-hand sightings of tigers right in front of her, tiger prints right in front of her - females and cubs - all that is exactly the kind of data we need.
And what this is showing is that large areas of Bhutan not only have tigers, but have tiger populations breeding.
So the source population that Bhutan will provide for the overall Himalayan tiger corridor now is growing and growing as we get more and more data.
With so many tiger populations facing a genetic dead end, Bhutan's extensive forests could serve as a tiger nursery, helping to repopulate other areas of the Himalayas.
More than ever now I believe that Bhutan is the key to what I envisioned as the Himalayan corridor.
If you think of the Himalayan corridor as a body, this really could be thought of as the heart, pumping blood out throughout the entire body, keeping it alive.
Much of the rest of the body is starting to die.
But this has the potential to not only keep it alive, but to invigorate the rest of the body.
Up-river, Steve's expedition has come to an abrupt halt.
Their path blocked by a near impossible rapid, they must judge whether there's a safe route through.
Looks pretty scary.
It does, doesn't it? It's quite intimidating really.
It's a lot of water going downstream.
How do you feel about it? Um My concern is that if I make a mistake, if I roll over up here somewhere and can't get back up again and get thrown into that washing machine, that would be, well it would be awful.
No.
it wouldn't be much fun.
It's one of those rapids, you've actually got to just pick your line, look exactly where you go and that's what you concentrate on and you just go for it, and make sure you nail it.
Hard left! Hard left! Hard left! Come on, come on, come on! Agh! Whoa! Woo-hoo! OK, Steve, can you hear me? I can hear you fine, Dave.
That looked like a hell of a run down the bottom, violent as anything.
Any advice for the raft just before we head on down? Just power left through those waves to begin with and make sure you go to the side of that massive hole.
You can't miss seeing it, but unfortunately I think you could miss and get dragged into it.
You've just got to power on through there, I think.
Woo! All forward.
This river better not get any bigger than that.
That is my absolute limit.
But this place is out of this world.
Back in camp, George is on bath duty.
This is great.
Alan has a new mission for him.
If Bhutan is to be at the heart of a massive tiger corridor, the team needs to discover what local people think about coexisting alongside big cats.
Alan has asked George to trek to a settlement up river.
George this is a really, really important trip that you're taking.
If the corridor is going to work, we know we've got the tigers here - the big cats - and we know that the young males are going to disperse outward from here, but we have to know if it can work once they go out into the human landscape, where they pass by human settlements.
So some of the stuff that's going to be really vital is what people feel about living among tigers.
If they value it? If they accept it? If they're angry about it? They're going to be one of our really important pieces to the puzzle.
Rebecca will introduce him to the people of Yumdang, a small village three hours' walk away.
Very wobbly! I'm very scared on the bridge.
I thought you'd be used to this? No, I walk, but I'm very scared all the time.
They are not alone on the forest path.
Ah! I've been leeched.
There'll be other ones, I'm sure.
They're all God's little creatures.
Ah! Look! How did it get on my finger? Even Eden has its problems.
I mean, look at this.
Every time you walk past, you will find a leech and they know exactly where you are.
I'm just holding my hand out and it's hot and it's reaching out, it's just desperate to get to me.
Oh! But I won't let you.
These are monsters.
That's going to bleed for a while.
In the east of Bhutan, Steve's stopping at each remote community along the Drangme Chhu valley to ask whether they've seen tigers.
There are many sightings, but the best is yet to come.
Just been chatting to this guy through two separate interpreters because he doesn't actually speak the normal Bhutanese language.
He's a farmer who moves around an awful lot around this area and has just come down with his cattle to a place quite close to here.
HE SPEAKS NATIVE LANGUAGE He think about this, maybe, in total.
In total when it was laid out.
Body like this, and tail like this.
What is actually quite interesting is that just two years ago, they actually found a tiger cub.
He said it was about this size, so it wasn't a young tiger cub - probably a year or even more old.
The fact that you've got a tiger that's with its mother, that's moving through an area like this is significant because it's usually the young males that are going to be actually travelling big distances to set up big territories.
Far more likely if you've got a mother with a young cub that she is actually living around here somewhere, and that would actually be quite a dramatic discovery.
News of breeding females in this far eastern part of the country is very good news indeed.
But even in these pristine forests, tigers will only survive if people accept predators on their doorstep.
You can't treat any habitat or any place on its own.
You have to include the human element.
And any efforts that you might do to conserve any particular animal or the whole habitat has to include a human element, because if you don't, your efforts are futile.
Before getting a chance to ask any questions, George is welcomed into a village game of kuru, the local version of darts.
You have to throw the dart at that object? What, from there?! Not from there.
From there to here.
You're throwing it from there to here? That's quite a long way.
I'm so going to lose here! I love the way they indicate the target, going, "Here, come on, hit it, come on.
" Are you going to stand there? I haven't thrown this before.
What if I miss? Oh! He's doing fine, because it's the first time he's playing, so that's why.
I think he couldn't hit the target, but after some time, it's possible he may hit the target.
Somehow, George's team wins.
THEY SING SHE LAUGHS GEORGE JOINS IN CHANTING THEY CHANT AND CHEER After ten days exploring the Drangme Chhu, Steve and the rafting team are approaching base camp.
During his dramatic, 100-kilometre journey, Steve has not only found tiger tracks, but has collected many eye-witness accounts of tigers living at several different locations along the river.
Here they come.
Hey, look at you.
Hey, Alan, how are you doing? I'm doing great, how about you? Really good.
You look great.
Wow, this is a strange sight.
Thank you very much.
How you been, buddy? Good.
Great to see you.
Was it a good trip? Really good.
Oh, it was absolutely incredible, yes.
Really? It's an amazing part of the world.
Well, before we go, you just have to tell me did you find any evidence Yes.
Yeah, yeah absolutely.
You're kidding? Almost everyone we spoke to had seen tigers.
The stories were, I would say very, very strong.
Some of them had seen them within weeks.
You're kidding? No, absolutely serious.
They said, "Yeah, they come through here quite regularly, I see their paw prints on the beach," or, "Someone in my village sees one every couple of months.
" Well, that's great.
One guy actually found a tiger cub within yards of his house.
That's phenomenal! It's very possible there are actually populations living along that whole riverine area.
That's great.
God, great news.
To farmers with livestock, news of wild predators living close by may not be so welcome.
You obviously keep animals here, you have cows and other domestic animals.
Have you ever heard of a case when those animals have been eaten or killed by wild animals? Ah, right, so if there was a wild cat, say a tiger was to ever kill one of your cattle, would you hunt it? It seems to be a very relaxed view of it.
In other areas of the world, if a wild animal was to kill a cow or something, they would be up in arms about it.
Everyone would be hunting it and make sure it ended its eating spree, so that's quite interesting.
You believe that humans and wild animals can exist in sort of harmony? Bye.
Bye-bye.
Thank you for the food.
Generally, it seems that they have quite a relaxed attitude towards wild animals.
They're happy they're here, they're happy that they have them around.
They believe that they should be in harmony with the animals and their habitat, and they love the forest.
They think their forest is absolutely great.
Such good will towards tigers is extraordinary.
It's a hopeful sign that Bhutan could be at the core of a successful Himalayan tiger corridor.
Gordon is back in camp, reviewing his remote cameras again.
If he has tiger images from several locations, Alan can work out the population density in this area.
Got nothing on this one.
It's been fired by something but I don't know what it is.
Up to now, he has captured four tiger shots.
Yes! Look at that.
You beauty.
This is great, it really is.
Alan is going to be very pleased with this.
Oh, you beautiful beast, look at that.
Cool as a cucumber.
They've got a real swagger to them that only the king of the forest has.
They've got a real confidence.
There's nothing in this forest that these tigers have to fear and you can see it in the way that they move.
Strutting around.
The only way of distinguishing one tiger from another is by looking at closely at their stripes.
Once you start looking at these tigers in detail, you realise that the stripe pattern is completely different.
They are as different to each other as humans are.
OK.
HE EXHALES Very good.
Gordon has captured 11 different tiger images.
Now he and Alan have to distinguish one animal from another.
Look at this one shot which we did.
Now we compared striping patterns of this individual - which is a beautiful side shot - to that individual.
Another great - pretty great - side shot.
Cool.
Pulled a single pattern out, and overlapped them.
Perfect, like a fingerprint.
Isn't that great? OK, that's great, except it means that those two shots are one tiger.
This is true of several of the pictures.
Now, there's one other shot.
Really nice, look at that, steps over the stream.
Good behaviour.
Nice behaviour shot.
We're comparing that to this tiger, coming straight, but we can look at these side stripes.
We can overlay those sides.
We can shift it, not at all.
So here we have clear, beautiful, two individual tigers.
Let's say out of all those shots we have, I think, possibly three individual tigers at least That's incredible.
.
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in a 40, 50 square kilometre area.
That's a good density.
That's really good in this area.
That would be about six tigers per 100 square kilometres.
That's a lot.
That's a really good density.
Bhutan doesn't just have a handful of tigers.
The evidence the team's collected from east to west points to a high natural density of this big cat, stretching across the southern half of the country.
There's just one final piece of the puzzle.
The team need to discover whether Bhutan's tigers are roaming into the mountainous north.
If they are, huge areas of the Himalayas can be included in the proposed tiger corridor.
Now Gordon's returning to check the remote cameras he left recording at high altitude at the start of the expedition.
George will assist him.
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, they've been clicking away and recording images up there.
The real important part of this expedition now is to find out if tigers can exist higher up in the Himalayas.
In the final phase, George spots a big cat on the edge of camp (It's behind you.
) .
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Steve is stalked by a snow leopard If a snow leopard can take down a yak, it certainly wouldn't struggle with me.
And I don't know where the hell I am.
.
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and Gordon makes the discovery of a lifetime.
Oh, my gosh! E- mail subtitling@bbc.
co.
uk
Now, an international team of scientists, filmmakers and explorers has been given unique access to the remote Himalayan kingdom of Bhutan.
If they can find a thriving population of tigers here, there's a chance to bring them back from the brink.
It's perfect tiger habitat.
But it won't be easy.
If a snow leopard can take down a yak, it certainly wouldn't struggle with me.
It can't get any worse that this.
THUNDER CRASHES Woo-hoo! They're taking on the wildest Himalayan rivers .
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fighting through the deepest jungles .
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and scaling the highest peaks.
My lungs are burning.
My legs are burning.
Do I really want to do this? What they discover could be the key to saving this magnificent big cat.
Can we save tigers? Absolutely we can save tigers.
We will save tigers.
Hidden in the foothills of the world's highest mountain range, lies the little known Kingdom of Bhutan.
These Himalayan forests could be the tiger's last hope for survival in the wild.
An expedition has set up camp on the banks of a river in the south of the country.
A hand-picked team has already spent 10 days searching for tigers.
They now have hard evidence these elusive cats are living close to base camp.
For this phase of the expedition, they will be spreading the net wider.
On his way to help them, is wildlife cameraman, Gordon Buchanan.
He's spent 10 years filming big cats worldwide.
It's amazing that we are looking out at what could be the future for tigers in the wild.
The only chance that they've got are them existing in hills like this.
He's already placed remote cameras high in the Himalayas, to try to capture images of tigers living at altitude.
Now, Gordon's joining forces with Doctor Alan Rabinowitz, one of the world's foremost tiger experts.
Alan has dedicated his life to saving tigers.
I'm not sure tigers will be able to survive.
I wake up wondering if there's any hope for the tiger.
If we continue on the course we are now, tigers will be extinct in the wild easily within a couple of decades.
With Gordon in camp, the team's reunited.
They've worked together around the world.
But this is their most critical mission so far.
They have just 10 days left here.
Alan gets Gordon straight up to speed with the images they've recorded close to camp.
Oh! Oh, my word.
Oh, gosh, they're beautiful.
There's no other animal like them.
And it walks that way.
It walks like, "nothing bothers me, I don't have to be afraid of anything in this forest".
It just walks that way! It's a promising start.
But now, the expedition needs more detailed information.
What I need you to do now is to get me more pieces of the puzzle.
How many more tigers are there in this area? How far in the river valleys are they heading up? For Bhutan to offer tigers a lifeline, Alan needs to know whether there's a continuous population, right across the country.
He's sent naturalist and expert tracker Steve Backshall up-river, far to the east.
The Drangme Chhu is the biggest river in Bhutan.
It actually starts way up in the high Himalaya.
It flows right across eastern Bhutan.
There are no records at all about tiger numbers in eastern Bhutan.
Nobody knows anything about them here.
If we could find any evidence at all of tigers here, that's vital information.
Through this rugged landscape, river valleys are natural highways for wildlife.
They are the best place to search for tigers.
Steve's journey will begin at the top of the Drangme Chhu.
He'll travel downstream, scouring the riverbanks for tiger tracks right the way back to base camp, 100 kilometres away.
That's where the proper mission begins.
As this river snakes away from the path that we've been walking on, it heads into some of the most unknown territory in Bhutan.
Down there is where we're really going to find some answers about the tiger and the future of the tiger in Bhutan.
Answers need to be found, and quickly.
Virtually nothing is known about Bhutan's vast forests, but we do know that elsewhere, tigers are in deep trouble.
In the last century, the world has lost 98% of its tigers.
Only small pockets survive.
There could be as few as 3,000 left in the wild.
But all hope is not lost.
Along the foothills of the Himalayas, where human pressure is not so intense, Alan has a plan to join together fragmented tiger populations and give them the space they need to roam.
It's an idea he's been working on for many years.
The solution I have for saving tigers is to connect these isolated populations through linkages in the landscape.
So that some of these tigers could move between isolated fragments and thus the isolated fragments become part of a larger whole.
Bhutan is the missing link.
In India, the more isolated tiger populations have become, the quicker they are dying out.
Even those living in protected reserves.
Oxford University biologist, Doctor George McGavin, is heading south to India, to find out why.
It will be a very different experience from the forests of Bhutan.
It's really only when you're up here, that you realise just how vast the forest is, and, you know, how many tigers are roaming down there, I wonder.
That's what Gordon wants to find out.
But to estimate the density of tigers in the forest around base camp, he must draw on all his field experience.
All along here is exactly where I'd expect to find tigers.
That sort of lush, green grass that's growing here, creatures like Sambar deer will come out and feed here at night time.
And tigers will come out and check if there's anything there for them to eat.
Each tiger hunts over a huge area.
So Gordon's decided his best chance is to blitz the forest with 30 remote cameras, which can record day and night.
What we're trying to do is figure out how many tigers are in this area, because it'll give us an overall indication of the health of the tiger population in this part of Bhutan.
So we need to distinguish one from the other and the best way of doing that is the stripe pattern on each side.
They have a unique, almost fingerprint pattern that their stripes make up, so if we can photograph as many tigers as possible, we should be able to tell one from another.
Far to the east, Steve's 10-day descent of the Drangme Chhu is about to begin.
Dave Allardice will lead three rafts carrying the expedition's food and filming gear.
He's navigated the biggest Himalayan rivers, and knows their dangers.
We're going to be very careful out there.
The water's running high, you can see it's snow melt.
There's quite a lot of water, so we'll have to be careful.
It's hard telling what's down there.
Yeah, I guess that's the thing - we're kind of paddling off into the unknown.
The team's found a calm spot to launch, but once they start, there's no escape from this steep-sided gorge.
The nerves are going just a little bit.
Also really, really optimistic about our chances of finding evidence of tigers moving through here.
And that's our big goal, really.
Steve and three other kayakers will scout each set of rapids to pick a safe route through for the rafts.
With the river running so high, there'll be no margin for error.
Near base camp, Gordon's setting camera traps.
They won't trigger unless an animal walks within a few metres.
Gordon now needs to think like a tiger.
Let me just go up here.
I am a tiger.
I am a tiger.
I am a tiger.
Oh, no.
I'm thinking about food.
I'm thinking about going to a place where I can get something to eat.
I think I'll cross here, because it's just a little leap like this.
And I would go this side of the rock.
Maybe just right here.
Tigers aren't the only wildlife the team's looking for.
Bhutan's forests remain largely unexplored, so the expedition is compiling a report of all the animals that live here.
Wildlife camera woman, Justine Evans, is walking the forest trails to see what creatures she can find.
It's a huge forest, and I think it's just a tough place to work, you know? It's a tough place to get shots.
Especially now when there's a lot of rain, there's a lot of food about, it's going to be a really difficult thing.
Off we go.
Alan will stay in camp to analyse camera trap images as they come in.
The amount of tiger prey gives him a picture of how many tigers this forest might support.
These camera traps, these are our eyes in the jungle.
So far, the tiger prey that we're getting in the camera traps - the Sambar deer and the gaur, they look beautiful.
But the team really wants to find tigers here.
And right across Bhutan.
Steve is in the east, on the wild, upper reaches of the Drangme Chhu.
It's so rugged, so remote.
You can see why nobody's ever penetrated into this place before.
I mean, you could never get down these canyon walls, and it's just an absolute haven for wildlife.
And hopefully, one of those will be our tiger.
Their search has been made much harder.
The Monsoon rains have arrived early.
The river is high and the rapids are now treacherous.
I've got a big rapid to the left.
Stop! I'm going to stay away from them.
Come on! Come on! Right now, tigers are the last thing on their minds.
Keep paddling! Hard right! Keep going.
Forward together again.
Come on! Keep right of that one.
Safely through the rapids, they look for a place to stop.
Sandy beaches are where Steve hopes to find tiger footprints.
But the rains have made his mission doubly difficult.
You can see all of this rain just spatters off the surface and makes all the prints totally indistinct.
Everything around me now, I mean, there's lots of animal prints here, I have no idea what any of them are.
Some of them could have been left yesterday.
It just makes our job almost impossible.
We need to find a tiger track that's been left within the last hour, that's the only way we're going to succeed.
The team press on.
They will explore every beach they come across.
100 kilometres down-river, Gordon's been dogged by rain too.
But his search is proving more productive.
Come and see this.
Nice.
Very nice.
These are the tracks of either a very small tiger or a leopard.
These are just ultra fresh.
Look at that - it's just literally just been made.
These are the first big cat tracks that I've found.
Oh, that's good.
Man, I was beginning to worry, because there's almost nothing coming up this river bed, not even Sambar deer, nothing.
And then to find this, is all the encouragement that I need to maybe put some remote cameras.
We've got a big cat right here.
Only if Gordon gets a picture of it can they tell whether it's a different tiger, or one they've already seen.
A thousand kilometres away, in India, George is travelling to Bandhavgarh Tiger Reserve to find out why every single tiger has become so precious.
HORN BEEPS Very loud horn for such a small scooter.
India used to have lots of tigers and they were all over the place, and now they're just clinging on to small, isolated reserves.
And they're surrounded by a sea of humanity and I don't really see how tigers will be able to survive in the long term, when they haven't got anywhere to go.
As the population of the Indian subcontinent has exploded, tigers have been pushed out of their former habitat.
Numerous protective reserves have been created, but tigers are now confined to far smaller ranges than they need.
There are 27 tigers in this core, which is about 100 kilometres square.
Which is the range of one male tiger in the wild.
There's not enough space within the park boundaries.
Inevitably, tigers wander outside, and into direct conflict with humans.
Local tiger expert, Digpal, has been battling with this problem for over 10 years.
What are the risks for a tiger, individual, if it has to go outside, if it's pushed out? They start killing cattle or buffalos, or whatever they get.
So the maximum risk is the villagers.
They poison the carcass, and that's where the poachers can also go.
So a very high risk outside? Very high risk, yes.
Tigers feed on a kill for several days.
If they prey on cattle outside the reserve, angry villagers poison the carcass.
When the tiger returns, it is doomed.
It's a world away from the unbroken forests of Bhutan.
Gordon is heading back to camp, to do a first check of his remote cameras.
One or two casualties, most of them intact.
That's how they're supposed to look.
This is how they look once an elephant has got hold of them.
HE LAUGHS Do you know what? I can probably repair that.
But just how good has Gordon been at second-guessing the tigers? Oh, my gosh! Wow, look at that.
Another one, another one.
Gordon's struck gold.
Images like this of tigers is precisely what we need.
Just look at that.
They are such amazing animals.
You know, if ever there was an animal on this planet worth saving, it has to be the tiger.
Gordon has four images, but they may all be the same animal.
He'll have to leave his remote cameras recording until the end of the expedition, and then compare all the images to see how many different tigers are living here.
In India, where tigers are trapped in small areas, George can easily see them with his own eyes.
Look there, look at it! Oh, my God.
Oh, look at that.
And there are two cubs.
There's an adult tiger, about 100 yards from the car.
So that is a female with her two cubs, who are about a year old.
Oh! They are beautiful, beautiful animals.
Oh, look at that.
They're practising their stalking.
Look at that.
That is so beautiful.
It seems slightly unreal, actually, I have to say.
I mean, seeing a tiger this close in Bhutan would be just unthinkable.
I mean, it would never, ever happen.
It's a privilege to view.
But these young tigers face an uncertain future.
When that male cub reaches a certain age, he'll have to move on.
And it's not clear what he would do.
He can't certainly occupy the same range as the other males in the park, so he'll have to go.
It's unlikely he'll get far beyond the park boundaries.
Even tigers within reserves are no longer safe from poachers, who supply the Chinese medicine market with tiger bones and body parts.
Even in the isolated populations, where the big cats still survive, they're under great threat.
They're being killed there as well.
But if we save tigers within the last remaining isolated populations, we still have a problem.
Because the long term survival of just an isolated population is in grave doubt.
To avoid genetic inbreeding, male tigers need to roam over vast distances to find new females.
Space is what Bhutan's forests could offer tigers along the Himalayas.
This is just incredible.
This fog forms over the top of the water, it almost looks like the river's on fire.
Oh, it's a cave.
It's a waterfall.
I'll bet this is home to thousands and thousands of bats.
While the rafting team makes camp for the night, Steve hunts for signs of tigers.
OK, this is going to seem like the most tenuous bit of tracking out there, but I have been asked to record every one of the tracks that fits a tiger profile, no matter how degraded.
These tracks, well, they're going in that direction, but that's the first one I spotted.
They're coming back down here .
.
and this one, I think, is the clearest.
It's very circular, seems to be heading in this direction and these look much more like toes to me than they do hooves.
The next thing really is just the size of it.
That is the perfect size .
.
for a tiger track.
There's no way you could say this was evidence, but Alan will be able to tell better than I can.
So I'm just going to take this data back, and hopefully he'll tell us more.
In India, George has spotted a fully grown adult male.
There he is.
Oh, God.
Look.
Look at him! Absolutely magnificent.
Look at him, look at him.
Ah, look at that.
Look at that.
What a magnificent beast.
It's the most incredible animal.
I'm hooked.
I'm hooked now.
TIGER ROARS Wow.
It's the first time I've heard a tiger roaring like that.
ROARING That noise is just amazing.
Pretty emotional, actually.
I feel very emotional.
I'm a bit shaky, actually, after that.
Seeing them now so close, it brings it home to me even more what a tragedy it would be if these animals were to ever become extinct.
The hope is that we can help the tiger, which is a very adaptable animal, to increase.
And, you know, it's not hard to do.
It requires prey, it needs space.
We've just got to stop hunting and poisoning and poaching and allow the animal to move freely.
In reality, what you want is a massive area through which you can roam.
Currently, all you've got is little fragments of original tiger habitat which hold a few individuals, and that won't work for very long.
We need to join these up and I now see how it'll work.
If you can join these areas up and tigers are able to move freely.
With so many people living in India, there is little chance of linking tiger reserves.
Along the less densely inhabited Himalayas, carefully managed land within a conservation corridor would offer tigers safe passage between isolated populations.
Creating one giant refuge in which they can roam and breed.
ALAN: The tiger corridor is an ambitious plan, but it's a very, very doable plan.
It's become Alan's life's work.
Nine years ago, he was diagnosed with incurable leukaemia.
There's not enough time for me.
I've got to spend whatever time I have left making sure that this tiger corridor becomes a reality.
Making sure that tigers are saved for the future.
I think about It's really interesting, because I try not to think about my leukaemia, and yet it's in my mind every single day.
It's in the back of my mind every waking hour, because it drives me now.
It drives me to keep on doing what I know I do best, right up until I can no longer do it.
The rest of the team is inspired to work day and night.
Justine's trying a new tactic, to learn more about what lives alongside the big cats here.
So what I'm doing now is I'm going to walk some of the trails at night.
With these elephants.
So I can conceal myself behind them, but also, their smell is quite domineering, so hopefully it will disguise my smell.
These are all just ideas I have and they may work.
If we cover enough distance, we've got a good chance of seeing some things.
And it's just nice to be out walking in the forest and not sitting and waiting.
I feel a bit more proactive.
Deep in the forest, Gordon's remote cameras are a secret window into this world .
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revealing behaviour which would never otherwise be seen.
A sambar deer stomps his forelegs nervously.
He's being stalked by wild dogs .
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ruthless predators who hunt in packs.
A wild boar investigates the camera, unaware of the shining eyes of a leopard just a few metres behind him.
And the ultimate reward - a tiger, out hunting.
The remote cameras free up Gordon to stalk the forest trails himself.
This time of day is when tigers, leopards start to prowl about, actually probably half an hour ago, so I am walking along here half expecting to bump into a big cat.
Most of the time, kills take place at night time, so that's why tigers start to get active round about now.
Heavens above.
Oh, two.
Two porcupines.
There's no mistaking what these creatures are.
There's nothing in this forest you could confuse them for.
I've actually seen a tiger with a porcupine quill stuck in its throat, so even something as prickly as this is still a meal for a tiger.
Camouflaged by the elephant's smell and sound, Justine is hoping that the wildlife won't noticed she's there.
Going around with these elephants is the opposite of being stealthy and quiet.
It's the opposite really of being a predator or being a tiger.
I think it's probably a good thing for prey animals because we don't seem like a threat to them.
We're not trying to stalk them or trying to be quiet, and they probably just think we're a herd of elephants.
Her thermal imaging camera picks up an animal's body heat and makes them easy to spot in the dark.
I've got something here.
Looks like a squirrel.
It should be climbing up.
It's going way up.
Wow, what was that? It's a flying squirrel! It just went flying through the frame.
I didn't realise there were flying squirrels here.
That's a great find.
Far to the east, Steve is searching the banks of the river.
It's a little bit nerve-racking wandering through this tall grass at night, knowing that this could be tiger territory and we could actually be being watched by a tiger right now.
This is by far the biggest spider I've seen in this part of the world, and it is absolutely furious.
Look at it reared up.
That's wonderful.
This is a primitive spider.
All over the world, they're known as tarantulas.
Big, hairy spiders, they're heavy-bodied with downward pointing fangs and he's bound to have small venom glands at the top here, and a bite from this would certainly really, really hurt.
Look how angry he is.
He's actually got just hanging from one fang the wing from, I don't know could be a termite.
That is absolutely remarkable.
Justine's tactics with the elephants are working.
Very bright eye-shine.
It's quite thick foliage in here.
Just see if I can get closer to whatever's in here.
It's quite hard to work out what it is exactly, cos it's all curled up having a snooze.
But it looks very much like a civet to me.
It's actually waking up now.
Preening his tail.
Oh, you can see the head much better now.
Big yawn.
It's definitely a civet.
He's having a good old lick on his paw now.
Beautiful.
He's probably going to be busy all night and then sleep all day.
Ah, look he's moving, he's moving.
That's really nice.
It's great on the thermal camera.
You can really see the shape.
Jump! He's going to jump again.
There he goes.
That was great.
Gordon has found another pair of eyes reflected in his torchlight.
Where are you? Oh! There he is, there he is.
Oh, you beautiful little cat.
He's been looking for the largest cat, but has found the smallest, a leopard cat.
Wow, he's tiny.
Is that a youngster? I wonder.
Yes.
Oh, this is what it is about.
He's on the move now.
He's kind of same size as a domestic cat, much longer legs, spotted like a leopard.
Beautiful.
You know these leopard cats, they'll catch small rodents, birds even.
Eating grass at the moment.
Whether it's a cat of this size or whether it's a cat the size of a tiger, there's just no denying them.
They're just perfect, they really are.
Steve's search for footprints has been frustrated by heavy rain so he's switched tack.
Along the river, there's a handful of communities, rarely visited by outsiders.
Steve will try to gather local intelligence about whether they've seen tigers.
So we have someone.
When was it that you saw this tiger and where? HE SPEAKS NATIVE LANGUAGE OK, this young man has seen a tiger just up here, down by the river, two weeks ago which is pretty incredible.
And where was it? HE SPEAKS NATIVE LANGUAGE So, he saw the tiger.
It was in the forest in the middle of the daytime, about 3 o'clock in the afternoon and it saw him and began to move away from him and this guy shouted at it and it ran off.
So So do you and your friends and you family see tigers often, many times, or is this a very unusual thing for you? HE SPEAKS NATIVE LANGUAGE Um, yeah, this is really quite striking news.
So he wasn't on his own, there was three of them there - his father and someone else as well - so it's not like he's just kind of making it up, and also when I asked how often they see tigers, he said maybe once a month, sometimes every two months.
That is absolutely extraordinary.
There must be a phenomenal amount of tigers moving through here for there to be any sightings at all, let alone regular sightings.
Last thing that Alan said to me before I left base camp was that if you get any evidence from people who live round here that there are tigers here - even just one person saying that they've seen one - then that's going to be massive, and you don't get any more definitive than that.
Heartened by success, Steve continues on towards base camp.
Back in camp, Alan is marking all confirmed tiger sightings on a map.
Expedition biologist Rebecca Pradan has spent many years trekking through western Bhutan, where she's seen tigers with her own eyes.
And when I saw that tiger, I was just pinching myself.
Weren't you scared? No, it's quite a little bit far away, so then after some time, there's two things climb up.
It's a little bit like a dog little bit smaller than a dog size cubs.
Both cubs were there.
So it was a female and two cubs? That's terrific.
You've had more close tiger encounters than I have ever had.
That's incredible.
All of the data is now coming together.
The fact that Rebecca has walked so much of Bhutan and has had first-hand sightings of tigers right in front of her, tiger prints right in front of her - females and cubs - all that is exactly the kind of data we need.
And what this is showing is that large areas of Bhutan not only have tigers, but have tiger populations breeding.
So the source population that Bhutan will provide for the overall Himalayan tiger corridor now is growing and growing as we get more and more data.
With so many tiger populations facing a genetic dead end, Bhutan's extensive forests could serve as a tiger nursery, helping to repopulate other areas of the Himalayas.
More than ever now I believe that Bhutan is the key to what I envisioned as the Himalayan corridor.
If you think of the Himalayan corridor as a body, this really could be thought of as the heart, pumping blood out throughout the entire body, keeping it alive.
Much of the rest of the body is starting to die.
But this has the potential to not only keep it alive, but to invigorate the rest of the body.
Up-river, Steve's expedition has come to an abrupt halt.
Their path blocked by a near impossible rapid, they must judge whether there's a safe route through.
Looks pretty scary.
It does, doesn't it? It's quite intimidating really.
It's a lot of water going downstream.
How do you feel about it? Um My concern is that if I make a mistake, if I roll over up here somewhere and can't get back up again and get thrown into that washing machine, that would be, well it would be awful.
No.
it wouldn't be much fun.
It's one of those rapids, you've actually got to just pick your line, look exactly where you go and that's what you concentrate on and you just go for it, and make sure you nail it.
Hard left! Hard left! Hard left! Come on, come on, come on! Agh! Whoa! Woo-hoo! OK, Steve, can you hear me? I can hear you fine, Dave.
That looked like a hell of a run down the bottom, violent as anything.
Any advice for the raft just before we head on down? Just power left through those waves to begin with and make sure you go to the side of that massive hole.
You can't miss seeing it, but unfortunately I think you could miss and get dragged into it.
You've just got to power on through there, I think.
Woo! All forward.
This river better not get any bigger than that.
That is my absolute limit.
But this place is out of this world.
Back in camp, George is on bath duty.
This is great.
Alan has a new mission for him.
If Bhutan is to be at the heart of a massive tiger corridor, the team needs to discover what local people think about coexisting alongside big cats.
Alan has asked George to trek to a settlement up river.
George this is a really, really important trip that you're taking.
If the corridor is going to work, we know we've got the tigers here - the big cats - and we know that the young males are going to disperse outward from here, but we have to know if it can work once they go out into the human landscape, where they pass by human settlements.
So some of the stuff that's going to be really vital is what people feel about living among tigers.
If they value it? If they accept it? If they're angry about it? They're going to be one of our really important pieces to the puzzle.
Rebecca will introduce him to the people of Yumdang, a small village three hours' walk away.
Very wobbly! I'm very scared on the bridge.
I thought you'd be used to this? No, I walk, but I'm very scared all the time.
They are not alone on the forest path.
Ah! I've been leeched.
There'll be other ones, I'm sure.
They're all God's little creatures.
Ah! Look! How did it get on my finger? Even Eden has its problems.
I mean, look at this.
Every time you walk past, you will find a leech and they know exactly where you are.
I'm just holding my hand out and it's hot and it's reaching out, it's just desperate to get to me.
Oh! But I won't let you.
These are monsters.
That's going to bleed for a while.
In the east of Bhutan, Steve's stopping at each remote community along the Drangme Chhu valley to ask whether they've seen tigers.
There are many sightings, but the best is yet to come.
Just been chatting to this guy through two separate interpreters because he doesn't actually speak the normal Bhutanese language.
He's a farmer who moves around an awful lot around this area and has just come down with his cattle to a place quite close to here.
HE SPEAKS NATIVE LANGUAGE He think about this, maybe, in total.
In total when it was laid out.
Body like this, and tail like this.
What is actually quite interesting is that just two years ago, they actually found a tiger cub.
He said it was about this size, so it wasn't a young tiger cub - probably a year or even more old.
The fact that you've got a tiger that's with its mother, that's moving through an area like this is significant because it's usually the young males that are going to be actually travelling big distances to set up big territories.
Far more likely if you've got a mother with a young cub that she is actually living around here somewhere, and that would actually be quite a dramatic discovery.
News of breeding females in this far eastern part of the country is very good news indeed.
But even in these pristine forests, tigers will only survive if people accept predators on their doorstep.
You can't treat any habitat or any place on its own.
You have to include the human element.
And any efforts that you might do to conserve any particular animal or the whole habitat has to include a human element, because if you don't, your efforts are futile.
Before getting a chance to ask any questions, George is welcomed into a village game of kuru, the local version of darts.
You have to throw the dart at that object? What, from there?! Not from there.
From there to here.
You're throwing it from there to here? That's quite a long way.
I'm so going to lose here! I love the way they indicate the target, going, "Here, come on, hit it, come on.
" Are you going to stand there? I haven't thrown this before.
What if I miss? Oh! He's doing fine, because it's the first time he's playing, so that's why.
I think he couldn't hit the target, but after some time, it's possible he may hit the target.
Somehow, George's team wins.
THEY SING SHE LAUGHS GEORGE JOINS IN CHANTING THEY CHANT AND CHEER After ten days exploring the Drangme Chhu, Steve and the rafting team are approaching base camp.
During his dramatic, 100-kilometre journey, Steve has not only found tiger tracks, but has collected many eye-witness accounts of tigers living at several different locations along the river.
Here they come.
Hey, look at you.
Hey, Alan, how are you doing? I'm doing great, how about you? Really good.
You look great.
Wow, this is a strange sight.
Thank you very much.
How you been, buddy? Good.
Great to see you.
Was it a good trip? Really good.
Oh, it was absolutely incredible, yes.
Really? It's an amazing part of the world.
Well, before we go, you just have to tell me did you find any evidence Yes.
Yeah, yeah absolutely.
You're kidding? Almost everyone we spoke to had seen tigers.
The stories were, I would say very, very strong.
Some of them had seen them within weeks.
You're kidding? No, absolutely serious.
They said, "Yeah, they come through here quite regularly, I see their paw prints on the beach," or, "Someone in my village sees one every couple of months.
" Well, that's great.
One guy actually found a tiger cub within yards of his house.
That's phenomenal! It's very possible there are actually populations living along that whole riverine area.
That's great.
God, great news.
To farmers with livestock, news of wild predators living close by may not be so welcome.
You obviously keep animals here, you have cows and other domestic animals.
Have you ever heard of a case when those animals have been eaten or killed by wild animals? Ah, right, so if there was a wild cat, say a tiger was to ever kill one of your cattle, would you hunt it? It seems to be a very relaxed view of it.
In other areas of the world, if a wild animal was to kill a cow or something, they would be up in arms about it.
Everyone would be hunting it and make sure it ended its eating spree, so that's quite interesting.
You believe that humans and wild animals can exist in sort of harmony? Bye.
Bye-bye.
Thank you for the food.
Generally, it seems that they have quite a relaxed attitude towards wild animals.
They're happy they're here, they're happy that they have them around.
They believe that they should be in harmony with the animals and their habitat, and they love the forest.
They think their forest is absolutely great.
Such good will towards tigers is extraordinary.
It's a hopeful sign that Bhutan could be at the core of a successful Himalayan tiger corridor.
Gordon is back in camp, reviewing his remote cameras again.
If he has tiger images from several locations, Alan can work out the population density in this area.
Got nothing on this one.
It's been fired by something but I don't know what it is.
Up to now, he has captured four tiger shots.
Yes! Look at that.
You beauty.
This is great, it really is.
Alan is going to be very pleased with this.
Oh, you beautiful beast, look at that.
Cool as a cucumber.
They've got a real swagger to them that only the king of the forest has.
They've got a real confidence.
There's nothing in this forest that these tigers have to fear and you can see it in the way that they move.
Strutting around.
The only way of distinguishing one tiger from another is by looking at closely at their stripes.
Once you start looking at these tigers in detail, you realise that the stripe pattern is completely different.
They are as different to each other as humans are.
OK.
HE EXHALES Very good.
Gordon has captured 11 different tiger images.
Now he and Alan have to distinguish one animal from another.
Look at this one shot which we did.
Now we compared striping patterns of this individual - which is a beautiful side shot - to that individual.
Another great - pretty great - side shot.
Cool.
Pulled a single pattern out, and overlapped them.
Perfect, like a fingerprint.
Isn't that great? OK, that's great, except it means that those two shots are one tiger.
This is true of several of the pictures.
Now, there's one other shot.
Really nice, look at that, steps over the stream.
Good behaviour.
Nice behaviour shot.
We're comparing that to this tiger, coming straight, but we can look at these side stripes.
We can overlay those sides.
We can shift it, not at all.
So here we have clear, beautiful, two individual tigers.
Let's say out of all those shots we have, I think, possibly three individual tigers at least That's incredible.
.
.
in a 40, 50 square kilometre area.
That's a good density.
That's really good in this area.
That would be about six tigers per 100 square kilometres.
That's a lot.
That's a really good density.
Bhutan doesn't just have a handful of tigers.
The evidence the team's collected from east to west points to a high natural density of this big cat, stretching across the southern half of the country.
There's just one final piece of the puzzle.
The team need to discover whether Bhutan's tigers are roaming into the mountainous north.
If they are, huge areas of the Himalayas can be included in the proposed tiger corridor.
Now Gordon's returning to check the remote cameras he left recording at high altitude at the start of the expedition.
George will assist him.
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, they've been clicking away and recording images up there.
The real important part of this expedition now is to find out if tigers can exist higher up in the Himalayas.
In the final phase, George spots a big cat on the edge of camp (It's behind you.
) .
.
Steve is stalked by a snow leopard If a snow leopard can take down a yak, it certainly wouldn't struggle with me.
And I don't know where the hell I am.
.
.
and Gordon makes the discovery of a lifetime.
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