Lost Land of the Volcano (2009) s01e03 Episode Script
Episode 3
On the far side of the world is a remote tropical island, carved by waterfalls and covered in thick jungle.
New Guinea.
At its heart are rugged mountains and deep gorges.
It's one of the least explored corners of our planet.
Over nine months, a team of scientists, adventurers and filmmakers have been on an expedition into the unknown.
Helped by a local tribe, they've found some of the strangest creatures on Earth.
Look at that.
Oh, wow, wow wow, wow! Jeepers! Now, they're leaving base camp and striking out in two directions.
One team is venturing to an erupting volcano.
Oh! It's being thrown a kilometre into the air.
The other team will journey deep into an unexplored crater, hoping to discover spectacular animals never seen by the outside world.
What is that? Absolutely out of this world.
Good God, look at that.
And they make a dramatic discovery.
That is the biggest I have ever seen.
Oh, my word, have a look at this.
New Guinea, the largest and most mountainous tropical island on Earth, so impenetrable, large areas remain uncharted.
At the heart of this vast island is Mount Bosavi, an extinct volcano.
Oh! Climber and naturalist Steve Backshall is leading the first-ever expedition deep into its huge crater.
This is what we do expeditions for, places like this.
Unimaginably beautiful, and totally unexplored.
Very few places in the world left like Mount Bosavi.
Outside the crater, they've already found new types of frogs, lizards and insects.
But inside, there could be unknown large mammals, hidden from the rest of the world.
These are the walls of the crater rim.
It's an almost perfect volcanic cone.
And what we're looking at now is the inside wall.
It's no wonder everyone's so excited about getting in this place.
It's absolutely epic.
Discovering new mammals in the crater would put Bosavi on the map and hopefully lead to its protection.
Loggers are just south of the mountain and moving closer.
High on the crater rim, there's a small gap in the trees.
The local Kasua tribe have agreed to meet Steve here.
They've given their blessing for the team to enter this, their most sacred land.
INDISTINCT SHOUTING The head of the clan that owns Bosavi is bringing up some magic, he's singing us into the crater, he's opening it for us so that the nature will be allowing us in there and not angry with us for going into the crater.
And we have to walk under the magic stick.
Even the Kasua rarely come here.
Fiercely territorial, this is the first time they've guided an expedition into their magical crater.
It's very steep and very wet.
Have to go very slowly.
Well done.
The clouds are just coming up to meet us.
Down there is a genuine lost world.
Just don't want to take a wrong step here, anywhere.
They need to find somewhere to build a rough camp.
Only then can they call in the rest of the team.
Outside the crater, at the foot of Mount Bosavi, the old base camp is packed up.
For now, intrepid bug expert George McGavin is venturing off on a side trip.
We're going.
Very excited about this indeed.
George will be searching for wildlife on the slopes of a very different volcano.
One that's erupting.
It's 700 miles to the east, on the island of New Britain.
Recently it's been quiet, but it could go off at any time.
Mile after mile is choked with ash, but George is keen to see what, if anything, can survive here.
At first, it appears barren.
It's more hell on Earth than wildlife hotspot.
Basically, it's just just covered in ash, and there isn't anything growing at all.
It's all dead, and decaying.
It smells of sulphur.
George's first discovery is perilously close to the crater.
This is a beautiful bird.
It's a brahminy kite.
The fact that it's flying around here means that there has to be enough food for it to eat.
Although I can't see much for it to eat, but it clearly is hunting.
If it's not careful it'll be hit by a rock in a minute.
It seems to be flying very close to the crater there.
A bird of prey is a promising sign, but George must also keep an eye out for flying rocks.
Mount Bosavi was once an active volcano.
It stopped erupting 200,000 years ago, and rainforest took over.
Since then it's remained unchanged, untouched and unexplored.
Steve and the team are following a river to the heart of the crater.
It's slow going, but it's the best way to cover ground in a dense jungle.
Not a bad spot.
Good spot.
Shall we try and get a tarp up before this rain starts? Yeah, yeah.
Shelter is essential.
New Guinea is one of the wettest places on Earth.
It can pour for days on end.
The Kasua tribe come from the outer slopes of the mountain.
These old men remember a time before any contact with the outside world, when their clan were cannibals.
HE SPEAKS NATIVE TONGUE They said their fathers were great warriors and used to battle with nearby clans quite often, but they also have, it seems, very vivid memories of them actually killing and eating their enemies.
The chief here is describing how he remembers them cutting the thighs into halves and putting them on stone fires to cook them, and it seems that it was not so much a ceremonial thing but actually just for the meat, for the protein, for the fact that meat was quite scarce around here and to have human meat was as good as anything.
They no longer eat people, but they are still expert hunters, totally at home in this jungle.
Without the tribe, the expedition would be lost.
200,000 years ago, Mount Bosavi would have looked like this, hostile and desolate.
But George knows better than anyone where to find signs of life.
This is definitely where I'd expect to find something.
Oh! Aha! Look at that, baby! Look at that.
A rhinoceros beetle larva.
It's a whopper.
Look at that.
Head's up here, big jaws, and they just eat this decaying wood and fibre.
Going to have to put him down somewhere.
Put him on there while I attack the rest of this.
Ah! Ha ha! There's the adult.
So there is what this will become eventually.
Rhinoceros beetle.
Absolutely brilliant.
Some creatures endure the volcano, others actually seek it out.
I can see two birds that look like sort of large hens.
They're megapode birds, and, bizarrely, they depend on this active volcano.
In the Bosavi crater, Steve and the trackers fan out to explore for the first time.
Steve will climb, crawl and swim the rivers to find out what lives here.
Chief Sigaro and the trackers search the high ground.
In the valley, Steve stumbles across something remarkable.
Absolutely out of this world.
It's a rare kind of kangaroo that climbs trees.
And it's probably never seen people before.
The fact that this animal is totally unafraid of humans, just wandered straight past us, means the wildlife here has never been hunted before - it hasn't seen people before.
I never expected to have a tree kangaroo on our first morning that we've been up and running.
This is a phenomenal start, a phenomenal start.
It's time to call in wildlife cameraman Gordon Buchanan.
Gordon's mission is to film any animal the team finds.
Many of the rainforests that I've been to before are quite flat.
This is a very, very difficult terrain, and without a doubt there'll be species down there that are completely unknown to science.
Finding and filming a large mammal that no-one knew existed would be the greatest prize of all.
But in this rugged terrain, it's a daunting prospect.
Gordon has with him two scientists, who will help to identify any mammals the team discovers.
Muse Opiang and Kris Helgen set up their makeshift jungle lab.
But Gordon has no time to unpack.
One of the trackers has found another tree kangaroo.
We've just had a shout from one of the local guys, shouting "toonape" which is the tree kangaroo, so I'm hoping to catch up before it goes.
As quick as we can.
Ah! Oh, yeah, he's here.
Oh, goodness me.
It's a glorious tree kangaroo, just literally six, seven metres in front of me.
For me, these animals are the height of weird.
They're one of the strangest animals that live in this forest, I think because they're recognisable, they're kangaroos, but these kangaroos live in the trees.
It's like a cross between a koala bear and a kangaroo.
Oh, he's very cute.
Really short, stocky build.
Huge claws.
The nails must be about two to three inches long.
Oh, yes, he's eating, oh, lovely.
Now that's a really good sign, because animals that feed are relaxed.
100%, this animal will never have seen a human being before, so that's why we're able to stay as close as this, as we are.
Tree kangaroos are incredibly rare.
Outside the crater, they're heavily hunted and afraid of people.
Inside, they aren't bothered by humans.
George's volcano could go off at any time, but he's too engrossed to care.
He's hot on the trail of the peculiar megapode bird.
One of them's just landed really clumsily on that branch and thrown up a whole shower of ash.
It's very hard to get close to these birds, they're very skittish.
(I reckon if we inch forward to this ridge) (They've landed, they're down.
There's two just on the ground (over there.
) Unlike any other bird, megapodes bury their eggs deep in the ash, and let the warmth of the volcano incubate them.
(The megapode egg-laying site is just down there.
) If George is to find an egg, he must wait for them to finish and hope the volcano stays quiet.
Mount Bosavi is extinct now, but the eruption left behind this crater four miles wide, enclosed by towering walls.
Steve's still out exploring the river .
.
but it's not just the rocks that are treacherous.
This plant is making life here absolute hell.
They're everywhere and they're called a stinging tree.
On the underside of each leaf are thousands of little hairs all filled with poison, and the sting, actually, can carry on going for two or three months.
Ow! Serves me right! Every little stream is investigated.
Any one might hide a surprise.
Sticking up out of this vine are lots of little twigs, except they're not twigs, they're leeches, just waiting for something to walk past.
They're switched on by warmth and also by the carbon dioxide you breathe out, and if I just breathe on them Look at that.
Instantly feeling around for the source of it.
Looking for a blood meal.
I hate them! Steve may hate them, but leeches mean there must be lots of warm-blooded animals to feed on.
It's an encouraging sign for the mammal experts.
Kris Helgen, from the Smithsonian Museum, is the world authority on identifying new mammal species.
From the river, Steve's brought in a fragment of skull.
You can see the pre-molar's fallen out and that corresponds to this too.
When you're studying mammals, the dentition, the arrangement of the teeth, the amount of teeth that are there, that's one of the most important things in figuring out what something is.
We're really lucky as mammologists, because if we find a single tooth or a single piece of skull, we can often tell exactly which species it is.
This is a mystery still, but I'd like to find the animal that goes along with this skull.
Let's see what we can find in the forest.
Wow.
So I could be holding in my hand the skull of a new species of mammal.
Let's see where it takes us.
Gordon and the scientists head out to look for Bosavi's mystery mammal.
Kris thinks it could be a new type of cuscus, a small bear-like animal.
There's spines on all these branches.
To be certain, they'll need to catch one alive.
It's quite a good flat area here.
As it's such a big trap, I need to find a big, flat space - you don't want any parts of the wire suspended.
Chuck this up the end.
Finding any animal, small or large, would be a bonus.
Everyone has their own technique for baiting the traps.
Tell you what, a little bit of peanut butter never hurts as well.
Throw that in the back there.
Smell it for miles.
At the volcano, George's wait is nearly over.
Now there should be eggs buried somewhere in the ash.
(I think the birds have finished laying now, so with any luck, (I should find some freshly-scraped ground, (which might indicate where the eggs are laid.
) Once the megapodes leave, the volcano will keep the eggs warm until they hatch.
This looks like exactly where they've been.
They could be as much as two metres underground.
I reckon down there is an egg.
When the chicks hatch out, alone and in the pitch black, they claw their way to the surface.
Well, I'm almost at as far as I can reach down.
Yes! I think I've got one! Ha ha! There is a megapode egg.
The size of it! The chicks emerge well developed, fending for themselves from day one.
They never know their parents.
What a tough start to life in this tough environment.
That was almost a scrambled egg then! He returns the egg to safety, but nearby, animal tracks lead him further into the danger zone.
That's getting a little too close for comfort.
That's coming halfway down the slope now, easily.
In the crater, Gordon and Kris are still out searching.
No, no.
It doesn't really go in.
That broken bit's hollow.
They're looking for the mystery cuscus, the mammal whose skull Steve found earlier.
Have a look in there.
Oh, crikey! You got somebody? Yeah.
Somebody's home? Something is holed up in an old tree trunk, but it's too deep to see what it is.
Just sitting there.
Let me have a look in there! Have a look.
God, that's the weirdest thing.
Oh, wow.
Gordon will have to wait for it to emerge.
What I want to do is just set up, maybe over there, wait for it to get dark and see what happens.
Quite exciting.
If it is the new type of cuscus, Gordon doesn't want to miss his chance to film it.
It's looking pretty good.
Just see what happens once I climb down.
A small camera pointing into the tree stump will warn him if the animal starts to climb up.
He can then film from a distance without disturbing it.
The problem with this situation is just the waiting for the animal to come out.
It will definitely come out, it's just a case of when.
The long wait begins.
The volcano is stirring, but George can't resist exploring just a little further.
This is what's making those tracks.
It's really quite a large crab, and Woo hoo! Ow.
The eyes are on these little stalks, which flick up and down, so that's how it keeps its eyes out of harm's way.
But that is clearly very at home here on this ash pile.
I mean, it's a long way from the sea.
Crabs are scavengers.
They've come to pick over anything killed by the volcano.
George must beat a hasty retreat.
His wildlife survey could be over.
The volcano is kicking off.
It's throwing out massive amounts of red hot rock, and you can hear the bangs as they hit the ground, the great thumps.
Look at that.
Oh, this is incredible.
I mean, it's fantastic to be this close to an active volcano.
It's throwing out massive amounts of hot rock, red-hot rock.
It's throwing them a kilometre in the air.
That is one of the most spectacular sights I think I've ever seen.
This is an infra-red camera, so it's able to see all the hot stuff, which the big cameras can't see.
When this thing erupts, you can feel the shockwaves hitting you.
That thing is on top of a chamber of molten rock three kilometres wide and three kilometres deep.
I mean, it's just terrifying.
But to be absolutely honest with you, I'm actually feeling quite apprehensive, because this is a force that just is too immense to even think about.
You couldn't speed away from this in a hurry.
You'd be toast.
Good grief! Four hours on, and still no sign of the unknown mammal.
I don't often feel as if I've got the upper hand on an animal.
I think in this case I do, because I can see the monitor of the camera that's looking straight down.
So it gives me a bit of warning.
If he's a bit agitated from me looking down into that tree stump earlier on, he might just shoot out and I won't get any shots of him, but at least that camera up there, I can see the moment he starts to climb up.
This is really exciting, because other than just two little eyes, I just don't know what's in there.
It's a mammal of some sort, but who knows what it is? OK, he's starting to come, he's starting to come.
Great! Come on, out you come.
Come on, come on.
We're evacuating camp, and in a hurry.
And with very good reason.
Show me, show me, show me.
That one? That's one of the bombs that came out.
We thought we were safe here, we were a long way away, and it landed here.
That would have killed you instantly.
So I think we should all go now.
George's mission has come to an abrupt end.
In the calm of the jungle night, Gordon's patience could be rewarded.
He's going to come out, he will.
Come on, come on.
Here he comes, looks like a mole.
I know it's not a mole, but it's very hard to tell what he is.
Oh, God, my heart is beating out of my chest, come on! Please, please, please oh, there he is, there he is, there he is! You little beauty! What is that? Gosh.
I haven't got a clue what he is.
That's weird.
That is so weird.
OK, if he just comes out a bit more, I can get an idea of his body shape, but you can see his teeth his eyes are shining like that because of this infrared light bouncing straight back at me.
What a pretty animal.
OK, out you come, come on, come on, please, just come out.
Gosh, look at that.
Oh, gosh, no, I think he's trying to go off - he's going to try and grab a limb and go off, oh, there.
There could well be new species living here in the crater, and my job is to get shots of them, and let Kris try and identify them.
Whatever it is, it appears to have no fear of people.
If unique to the crater, it would help prove just how special the jungles of Bosavi are.
Whilst Gordon is deep in the jungle, Steve is on the river.
No-one knows what may lurk here at night.
Eughh! Look! Whoa! They've been roosting just in the branches above us so as we've come across with our torches and lights, it's given them a shock.
Steve is being mobbed by torrent flycatchers, birds found only in New Guinea.
Eughh! It just flew right into my face.
It may be wet, but no-one imagined there would be ducks in the jungle.
Now that is something I really didn't expect to see! Salvadori's teal - unique to the mountain rivers of New Guinea.
They almost look like they're just enjoying the rapids! That is a glorious looking little tree frog.
Off he goes.
Wow! These are actually torrent breeding frogs, so they love breeding in fast-flowing water like this.
Let's see if we can get a glance at what makes this frog really special.
That eyelid is laced through with a network of veins and it's absolutely beautiful.
He's got a face that you just can't help but love, and you know that any second, although he's sitting comfortably on my finger here, he could, without a single warning, just spring away and be gone.
Come on, go and find yourself a girlfriend.
Not the ear! Mount Bosavi is so large it generates its own weather.
For much of the night it's been raining, and the sleeping area is flooding.
There's no respite from the mud.
And it's tinned spaghetti for breakfast, again.
Kris and Steve are reviewing Gordon's footage from last night, in the hope it's the mystery cuscus they've been looking for.
Those big beautiful eyes.
Yeah.
It's small little ears, they're in the fur.
And light belly here.
Light belly.
I reckon that is our cuscus.
You think? I reckon it is.
I reckon it is, it's dark.
So this could be the animal that that skull belongs to.
This could be the mysterious Bosavi cuscus.
This could definitely be.
Wow.
So what we really need now is to actually catch one of these in our traps.
Then we'll get a feel for the colour, we'll see what it really looks like, and if that really is a good match for the animal's teeth that we've been looking at that are so distinctive.
Yeah.
This could be really exciting now, I think this is our animal.
It looks like a major new discovery, but pictures alone are not scientific proof.
To get that, they'll need to catch one in the few days that are left.
Bosavi's forests extend right up to the summit.
A vertical kilometre above Steve and Gordon, the jungle is much wetter.
George is joining the team on the mountain.
His mission to explore the cloud forest clinging to the summit.
Being one of the world's leading experts on insects, if there's anything unusual, he'll find it.
This volcano is just like like an island in the sky.
I mean, it's 9,000 feet above sea level.
Look at that wall! God, that is unbelievable.
But as you can see, the weather's really very cloudy.
It's amazing how it changes incredibly heavy rain, very dark, and then just a little a little gap in the cloud cover there.
So it's touch and go whether we'll be able to land there.
We're gonna make it.
We're clear to land, we're clear to land.
Oh yeah, we're here! Fantastic.
This precarious cliff edge will be George's camp for the next couple of days.
A thousand metres below him, they're on the look out for new animals.
Top of their list - the unknown cuscus.
They search every hole Every nook and every cranny Mate, this place is leech central.
.
.
By day .
.
And by night.
Camera traps are set.
Leech.
Any mammals that come in here they'll try and get on to them, including humans.
A face only a mother could love.
The team use every piece of kit available.
Lots of insect noise, some frogs.
Some weird stuff, I don't know what it is.
It's incredible that a frog this tiny size, I mean it's no bigger than the end of my thumb, can make a noise that loud, just puffing itself up like a great big balloon and then squeezing all the air out.
But this jungle is so dense and so steep, it's hard to find anything.
On the summit, George is out exploring the peculiar mountain moss forest for the first time.
He's stepped into another world.
It's like Lord Of The Rings habitat.
You'd expect orcs and elves appearing any minute.
The whole forest is just humid, 100% humidity all the time, and this may look like solid ground, but it's not.
Look, I can go through there and beyond.
I can put my hand I can go, probably, I can put my whole arm right through up to the hilt and that's just roots and soil and space, and that's what we're standing on.
The whole thing is just a sort of a mirage, almost, of plants and soil, but the soil's really interesting because the soil isn't just here, it actually occurs up on the plants as well.
So it's actually aerial soil - all of this is just growing on a single thin branch.
It's a huge carpet of moss and soil.
It's almost like a different world.
I haven't seen that one before.
Absolutely amazing.
I mean, decay just brings fungi, bacteria, mosses - just everything is feeding off what's here.
And look at that, that is the most exquisite tiny fungus growing on a dwarf bamboo, and it is just incredible.
Ooh, look, look! Good God, look at that! I just saw that there in the ground.
It's huge! This is a flatworm.
Well, that's exactly the sort of animal you'd expect to find in this constantly wet environment.
Flatworms come in all shapes and sizes that's the underside but I have never seen a flatworm this big before.
It's absolutely amazing.
Tiny little head end, that's the head end there.
This habitat is incredibly special, because there are animals and plants here, orchids and insects and higher animals you won't find anywhere else in the world.
But also because it occupies a very, very small area and with increased global warming, that area will get smaller and smaller and smaller and eventually it'll all be gone.
In the crater, one of the trackers has returned to camp with a wild animal, and it's totally trusting.
Oh, wow! Oh, my goodness, he's absolutely beautiful.
Come on little fella.
I think it's our guy.
I'm going to look in his mouth in a bit and we'll know from his teeth but this looks right on.
This is a dark-furred cuscus, it's a montane cuscus.
It's very much like the skull I suspected.
The skull was similar to a different species called the silky cuscus, and the body is too, you can feel that silky fur.
It's really, really thick.
I guess this has adapted to living in a mountain environment.
That's right.
He seems to like you.
He's got a very, very strong, but not actually unpleasant, smell.
But it does hit you.
This is the mammal that Gordon filmed emerging from the tree stump.
I'm calling this the Bosavi cuscus, because I really think it has a lot of distinctive features.
We're gonna find out more as we look closer, but I just I can't even begin to describe how it feels to have an animal in my hands that is this beautiful and, in all probability, has never been seen before by science.
I think what we have is a cuscus that long ago has been isolated on this volcano and has just not been able to have any contact with any of its relatives and has become something here in isolation that is unique to Bosavi.
He's totally chilled out.
He's got no idea quite how important he is.
So gorgeous.
Yeah! Little guy! You're a major scientific discovery.
How about that? I travel the world looking for new species in many different places and we find new mammals, it still does happen, but so many of them, most of them are things like bats and rodents, and to find something, a marsupial, an animal that's this size is really exciting, it's a cause for a major celebration.
Crack open the champagne, or crack open the bully beef! It's a brand new sub-species of cuscus, and Bosavi is its only home.
If these jungles are logged, we'll lose animals like this forever.
Both on the summit and in the crater, the rainforest is undisturbed by humans.
Animals are remarkably naive.
Almost incredibly, I'm about six feet away from an ornate fruit-dove.
You couldn't normally get this close to birds, especially on the nest.
She's camouflaged to perfection against the foliage - green with a little bit of blue at the back, this ochre-y head and a white bit underneath.
She's being very vigilant, she's watching me very carefully and turning her head from side to side, very slowly.
Amazing.
Thing about animals here is that they really aren't experienced, they don't know what humans are all about yet, which may be a problem for them.
The history of humans has been that if animals are edible or hazardous, they usually end up dead.
In the depths of the crater, it's raining again.
It's been a long, hard expedition.
Exhaustion and illness are setting in.
There's been an outbreak of intestinal worms in the camp, so we're all taking these worming tablets which will pretty much kill everything we've got in our guts.
Makes you feel really run down, but this tablet just kills everything.
Leeches are infesting camp.
Gordon and Kris take time to see if anything strange has been caught on the camera traps.
Let's have a look.
OK, that's me still me.
Kris is one of the few people in the world who can distinguish what's just rare from what's totally new.
Oh! Is that a tree kangaroo? It's not a tree kangaroo, but it is a kangaroo.
So it's a wallaby.
Moves along the forest floor here in the crater.
See what else we've got.
I've got a good feeling about this one.
They scan hundreds of images, and eventually, they strike gold.
Wow! Have a look at that.
What is that? That long, naked tail, what do you think that is? It just looks like an enormous rat.
Yes, it's a giant rat, it's a woolly giant rat.
Jeez, it must be that size without its so that size with its tail? Exactly, almost a metre long.
Seriously? And this camera trap proves that an animal like that is here.
To get conclusive evidence whether this is a new species, you need more than a photograph.
This black and white photograph isn't going to do it.
We're going to have to see if we can find this animal in the flesh, hold it, see what this animal is.
But just using your experience, this could be a new species? There's no question in my mind this is a giant woolly rat, and I suspect Bosavi has its own kind.
Wow, that would be some amazing find.
No-one imagined just how rich this mountain would turn out to be.
In the weird moss forest that clings to the rim of the crater, George is setting a trap.
It's carefully positioned, right on the cliff edge.
Once night falls, a high-powered light bulb will be switched on to attract insects to the sheet.
And that's going to be hopefully, it's going to be heaving with bugs.
Down below, the hunt is on for the giant woolly rat.
Gordon and Steve head off in opposite directions.
They will search all night if they have to.
Somewhere out there in the darkness is one of the world's biggest rats.
At night, the jungle has its own special magic.
This tree is covered in bracket fungus, and you can see all the tiny little spores being discharged, it makes it look as if they're actually steaming.
In the early hours, Kris finds another animal with no fear of humans.
It looks like a giant hamster, but it's a painted ringtail.
Oh, he's absolutely gorgeous! Not a new species, but definitely one of the most beautiful animals that lives in this forest.
Gosh, he really is.
The fur is just exquisite.
It is just so dense and so soft.
You can see at night time this place just comes alive.
We've done so much walking about this forest finding nothing, and you only have to find something like this and it makes it all worthwhile.
You forget all that misery and all that hardship.
On the cliff edge, George can hardly believe his eyes.
I'm just overwhelmed.
I never imagined I'd see such a diversity of moth.
I mean, some of these things I've never seen before in my life.
The variety of moths here is absolutely staggering! There's geometrids, hawkmoths, there's fruit piercing moths, and it's raining, it's tipping it down! This shouldn't be happening, and these bulbs only work in a radius of about 200 yards.
All this has come from a 200 yard radius to this bulb.
Can you imagine how rich this forest actually is? Almost beyond my understanding.
Look at that.
I'm absolutely incredulous.
My God, look at it! Look at that one, that brassy gold colour.
In the crater, Steve's searching for the giant rat, but he's discovered a tarantula.
Look at that! The way he's tilted back there, you can see he's rocked back in order to bring those fangs into position so he can bring down the entire bodyweight, plunging those fangs into whatever it is that's annoying him.
Come on then.
Now don't go, don't go.
I do have to be careful here, I'd be a lot more ambitious if I knew what it was and if we were in a less remote environment.
But to get bitten or stung by something like this out here .
.
could be really sketchy.
I have never been anywhere where I've seen the diversity of moths that I'm seeing here.
If you'd told me, I wouldn't have believed you, but it's here.
This one! That's a different hawkmoth.
That's a different one come in now, just now.
V- shaped wings, very fast flyers, really strong moths.
Fantastic colouration there.
Oh, look now, there's a hawkmoth too.
Now, I've never seen that one before.
What percentage of these will be new? It could easily be a quarter, it could easily be a quarter of them.
This is a very interesting moth.
It's called an arctiid moth and when it's annoyed, it produces very horrible-smelling fluid from the thorax.
There, see that? Look at that! That is amazing! What a defence.
And that tastes really foul.
Yuk, yuk.
Even if I'd had to walk up here on my hands and knees, it would have been worth it for this.
This one hour of moth mayhem.
A haul of unique creatures like this proves Bosavi's forests are priceless.
Honestly! Gordon gets a shout from a tracker.
Oh, my word, have a look at this! Oh, gosh, that is the biggest rat I have ever seen.
That is a murid rat, a true rat, the same family as the rats you find in cities and sewers.
You've got a big smile on your face.
The reason I'm smiling is because this is absolutely a new species.
This is something that doesn't have a scientific name.
This is one of the largest rats in the world, and here we are, holding it.
I just think it's an amazing creature, found nowhere else on the entire planet.
That is such a huge deal.
And this animal is so chilled out, look at him, he's just grooming.
You can tell it's a rat but yet it looks just so different from any rat you've ever seen, right? Yeah.
I had a cat, and the cat was about the same size as this rat.
Any cat that you buy to catch rats is going to run a mile from something like this.
Mount Bosavi's such a big mountain, it's largely unexplored, it's so isolated that truly, some of the things we are finding are new species and are spectacular new species.
Big rats, cuscus, fantastic animals.
It gave me the heebie-jeebies, the thought of a giant rat and I've been going down the holes in hollow trees looking for big things, and it's actually kept me awake at night and here he is, he's just oh, he's like a little puppy.
New species of giant woolly rat! Yeah.
No! That's unbelievable.
Or are you just making it up? No, no, we got it, we got it, yeah.
God, it was great, so great.
The biggest rat in the world.
Was it in a trap or was it? No, just running about the forest, tame as anything.
That's incredible.
It's time to pack up and collect George from the summit.
As I stand here, just about to be whisked away by this helicopter, I realise that my grandchildren may not ever be able to see this sort of habitat or the animals and plants that live here.
It could all be gone.
Now all their findings will be brought together and presented to the outside world.
With the help of a remarkable tribe, they've found hundreds of spectacular creatures.
He is just a parrot in miniature.
That is absolutely gorgeous! They've discovered over 40 new species, from exquisite geckos to magical moths and bizarre frogs.
And they've made major scientific discoveries creatures with no fear of people.
Oh, he's like a little puppy! Mammals that no-one knew existed.
Wow! It's so incredibly rare that new species of mammal are found around the world these days.
This has got to be one of the most incredible moments of my life.
All of this on one amazing mountain.
The hope is that Mount Bosavi, once a forgotten corner, will now become known around the world and protected as a unique rainforest of global importance.
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New Guinea.
At its heart are rugged mountains and deep gorges.
It's one of the least explored corners of our planet.
Over nine months, a team of scientists, adventurers and filmmakers have been on an expedition into the unknown.
Helped by a local tribe, they've found some of the strangest creatures on Earth.
Look at that.
Oh, wow, wow wow, wow! Jeepers! Now, they're leaving base camp and striking out in two directions.
One team is venturing to an erupting volcano.
Oh! It's being thrown a kilometre into the air.
The other team will journey deep into an unexplored crater, hoping to discover spectacular animals never seen by the outside world.
What is that? Absolutely out of this world.
Good God, look at that.
And they make a dramatic discovery.
That is the biggest I have ever seen.
Oh, my word, have a look at this.
New Guinea, the largest and most mountainous tropical island on Earth, so impenetrable, large areas remain uncharted.
At the heart of this vast island is Mount Bosavi, an extinct volcano.
Oh! Climber and naturalist Steve Backshall is leading the first-ever expedition deep into its huge crater.
This is what we do expeditions for, places like this.
Unimaginably beautiful, and totally unexplored.
Very few places in the world left like Mount Bosavi.
Outside the crater, they've already found new types of frogs, lizards and insects.
But inside, there could be unknown large mammals, hidden from the rest of the world.
These are the walls of the crater rim.
It's an almost perfect volcanic cone.
And what we're looking at now is the inside wall.
It's no wonder everyone's so excited about getting in this place.
It's absolutely epic.
Discovering new mammals in the crater would put Bosavi on the map and hopefully lead to its protection.
Loggers are just south of the mountain and moving closer.
High on the crater rim, there's a small gap in the trees.
The local Kasua tribe have agreed to meet Steve here.
They've given their blessing for the team to enter this, their most sacred land.
INDISTINCT SHOUTING The head of the clan that owns Bosavi is bringing up some magic, he's singing us into the crater, he's opening it for us so that the nature will be allowing us in there and not angry with us for going into the crater.
And we have to walk under the magic stick.
Even the Kasua rarely come here.
Fiercely territorial, this is the first time they've guided an expedition into their magical crater.
It's very steep and very wet.
Have to go very slowly.
Well done.
The clouds are just coming up to meet us.
Down there is a genuine lost world.
Just don't want to take a wrong step here, anywhere.
They need to find somewhere to build a rough camp.
Only then can they call in the rest of the team.
Outside the crater, at the foot of Mount Bosavi, the old base camp is packed up.
For now, intrepid bug expert George McGavin is venturing off on a side trip.
We're going.
Very excited about this indeed.
George will be searching for wildlife on the slopes of a very different volcano.
One that's erupting.
It's 700 miles to the east, on the island of New Britain.
Recently it's been quiet, but it could go off at any time.
Mile after mile is choked with ash, but George is keen to see what, if anything, can survive here.
At first, it appears barren.
It's more hell on Earth than wildlife hotspot.
Basically, it's just just covered in ash, and there isn't anything growing at all.
It's all dead, and decaying.
It smells of sulphur.
George's first discovery is perilously close to the crater.
This is a beautiful bird.
It's a brahminy kite.
The fact that it's flying around here means that there has to be enough food for it to eat.
Although I can't see much for it to eat, but it clearly is hunting.
If it's not careful it'll be hit by a rock in a minute.
It seems to be flying very close to the crater there.
A bird of prey is a promising sign, but George must also keep an eye out for flying rocks.
Mount Bosavi was once an active volcano.
It stopped erupting 200,000 years ago, and rainforest took over.
Since then it's remained unchanged, untouched and unexplored.
Steve and the team are following a river to the heart of the crater.
It's slow going, but it's the best way to cover ground in a dense jungle.
Not a bad spot.
Good spot.
Shall we try and get a tarp up before this rain starts? Yeah, yeah.
Shelter is essential.
New Guinea is one of the wettest places on Earth.
It can pour for days on end.
The Kasua tribe come from the outer slopes of the mountain.
These old men remember a time before any contact with the outside world, when their clan were cannibals.
HE SPEAKS NATIVE TONGUE They said their fathers were great warriors and used to battle with nearby clans quite often, but they also have, it seems, very vivid memories of them actually killing and eating their enemies.
The chief here is describing how he remembers them cutting the thighs into halves and putting them on stone fires to cook them, and it seems that it was not so much a ceremonial thing but actually just for the meat, for the protein, for the fact that meat was quite scarce around here and to have human meat was as good as anything.
They no longer eat people, but they are still expert hunters, totally at home in this jungle.
Without the tribe, the expedition would be lost.
200,000 years ago, Mount Bosavi would have looked like this, hostile and desolate.
But George knows better than anyone where to find signs of life.
This is definitely where I'd expect to find something.
Oh! Aha! Look at that, baby! Look at that.
A rhinoceros beetle larva.
It's a whopper.
Look at that.
Head's up here, big jaws, and they just eat this decaying wood and fibre.
Going to have to put him down somewhere.
Put him on there while I attack the rest of this.
Ah! Ha ha! There's the adult.
So there is what this will become eventually.
Rhinoceros beetle.
Absolutely brilliant.
Some creatures endure the volcano, others actually seek it out.
I can see two birds that look like sort of large hens.
They're megapode birds, and, bizarrely, they depend on this active volcano.
In the Bosavi crater, Steve and the trackers fan out to explore for the first time.
Steve will climb, crawl and swim the rivers to find out what lives here.
Chief Sigaro and the trackers search the high ground.
In the valley, Steve stumbles across something remarkable.
Absolutely out of this world.
It's a rare kind of kangaroo that climbs trees.
And it's probably never seen people before.
The fact that this animal is totally unafraid of humans, just wandered straight past us, means the wildlife here has never been hunted before - it hasn't seen people before.
I never expected to have a tree kangaroo on our first morning that we've been up and running.
This is a phenomenal start, a phenomenal start.
It's time to call in wildlife cameraman Gordon Buchanan.
Gordon's mission is to film any animal the team finds.
Many of the rainforests that I've been to before are quite flat.
This is a very, very difficult terrain, and without a doubt there'll be species down there that are completely unknown to science.
Finding and filming a large mammal that no-one knew existed would be the greatest prize of all.
But in this rugged terrain, it's a daunting prospect.
Gordon has with him two scientists, who will help to identify any mammals the team discovers.
Muse Opiang and Kris Helgen set up their makeshift jungle lab.
But Gordon has no time to unpack.
One of the trackers has found another tree kangaroo.
We've just had a shout from one of the local guys, shouting "toonape" which is the tree kangaroo, so I'm hoping to catch up before it goes.
As quick as we can.
Ah! Oh, yeah, he's here.
Oh, goodness me.
It's a glorious tree kangaroo, just literally six, seven metres in front of me.
For me, these animals are the height of weird.
They're one of the strangest animals that live in this forest, I think because they're recognisable, they're kangaroos, but these kangaroos live in the trees.
It's like a cross between a koala bear and a kangaroo.
Oh, he's very cute.
Really short, stocky build.
Huge claws.
The nails must be about two to three inches long.
Oh, yes, he's eating, oh, lovely.
Now that's a really good sign, because animals that feed are relaxed.
100%, this animal will never have seen a human being before, so that's why we're able to stay as close as this, as we are.
Tree kangaroos are incredibly rare.
Outside the crater, they're heavily hunted and afraid of people.
Inside, they aren't bothered by humans.
George's volcano could go off at any time, but he's too engrossed to care.
He's hot on the trail of the peculiar megapode bird.
One of them's just landed really clumsily on that branch and thrown up a whole shower of ash.
It's very hard to get close to these birds, they're very skittish.
(I reckon if we inch forward to this ridge) (They've landed, they're down.
There's two just on the ground (over there.
) Unlike any other bird, megapodes bury their eggs deep in the ash, and let the warmth of the volcano incubate them.
(The megapode egg-laying site is just down there.
) If George is to find an egg, he must wait for them to finish and hope the volcano stays quiet.
Mount Bosavi is extinct now, but the eruption left behind this crater four miles wide, enclosed by towering walls.
Steve's still out exploring the river .
.
but it's not just the rocks that are treacherous.
This plant is making life here absolute hell.
They're everywhere and they're called a stinging tree.
On the underside of each leaf are thousands of little hairs all filled with poison, and the sting, actually, can carry on going for two or three months.
Ow! Serves me right! Every little stream is investigated.
Any one might hide a surprise.
Sticking up out of this vine are lots of little twigs, except they're not twigs, they're leeches, just waiting for something to walk past.
They're switched on by warmth and also by the carbon dioxide you breathe out, and if I just breathe on them Look at that.
Instantly feeling around for the source of it.
Looking for a blood meal.
I hate them! Steve may hate them, but leeches mean there must be lots of warm-blooded animals to feed on.
It's an encouraging sign for the mammal experts.
Kris Helgen, from the Smithsonian Museum, is the world authority on identifying new mammal species.
From the river, Steve's brought in a fragment of skull.
You can see the pre-molar's fallen out and that corresponds to this too.
When you're studying mammals, the dentition, the arrangement of the teeth, the amount of teeth that are there, that's one of the most important things in figuring out what something is.
We're really lucky as mammologists, because if we find a single tooth or a single piece of skull, we can often tell exactly which species it is.
This is a mystery still, but I'd like to find the animal that goes along with this skull.
Let's see what we can find in the forest.
Wow.
So I could be holding in my hand the skull of a new species of mammal.
Let's see where it takes us.
Gordon and the scientists head out to look for Bosavi's mystery mammal.
Kris thinks it could be a new type of cuscus, a small bear-like animal.
There's spines on all these branches.
To be certain, they'll need to catch one alive.
It's quite a good flat area here.
As it's such a big trap, I need to find a big, flat space - you don't want any parts of the wire suspended.
Chuck this up the end.
Finding any animal, small or large, would be a bonus.
Everyone has their own technique for baiting the traps.
Tell you what, a little bit of peanut butter never hurts as well.
Throw that in the back there.
Smell it for miles.
At the volcano, George's wait is nearly over.
Now there should be eggs buried somewhere in the ash.
(I think the birds have finished laying now, so with any luck, (I should find some freshly-scraped ground, (which might indicate where the eggs are laid.
) Once the megapodes leave, the volcano will keep the eggs warm until they hatch.
This looks like exactly where they've been.
They could be as much as two metres underground.
I reckon down there is an egg.
When the chicks hatch out, alone and in the pitch black, they claw their way to the surface.
Well, I'm almost at as far as I can reach down.
Yes! I think I've got one! Ha ha! There is a megapode egg.
The size of it! The chicks emerge well developed, fending for themselves from day one.
They never know their parents.
What a tough start to life in this tough environment.
That was almost a scrambled egg then! He returns the egg to safety, but nearby, animal tracks lead him further into the danger zone.
That's getting a little too close for comfort.
That's coming halfway down the slope now, easily.
In the crater, Gordon and Kris are still out searching.
No, no.
It doesn't really go in.
That broken bit's hollow.
They're looking for the mystery cuscus, the mammal whose skull Steve found earlier.
Have a look in there.
Oh, crikey! You got somebody? Yeah.
Somebody's home? Something is holed up in an old tree trunk, but it's too deep to see what it is.
Just sitting there.
Let me have a look in there! Have a look.
God, that's the weirdest thing.
Oh, wow.
Gordon will have to wait for it to emerge.
What I want to do is just set up, maybe over there, wait for it to get dark and see what happens.
Quite exciting.
If it is the new type of cuscus, Gordon doesn't want to miss his chance to film it.
It's looking pretty good.
Just see what happens once I climb down.
A small camera pointing into the tree stump will warn him if the animal starts to climb up.
He can then film from a distance without disturbing it.
The problem with this situation is just the waiting for the animal to come out.
It will definitely come out, it's just a case of when.
The long wait begins.
The volcano is stirring, but George can't resist exploring just a little further.
This is what's making those tracks.
It's really quite a large crab, and Woo hoo! Ow.
The eyes are on these little stalks, which flick up and down, so that's how it keeps its eyes out of harm's way.
But that is clearly very at home here on this ash pile.
I mean, it's a long way from the sea.
Crabs are scavengers.
They've come to pick over anything killed by the volcano.
George must beat a hasty retreat.
His wildlife survey could be over.
The volcano is kicking off.
It's throwing out massive amounts of red hot rock, and you can hear the bangs as they hit the ground, the great thumps.
Look at that.
Oh, this is incredible.
I mean, it's fantastic to be this close to an active volcano.
It's throwing out massive amounts of hot rock, red-hot rock.
It's throwing them a kilometre in the air.
That is one of the most spectacular sights I think I've ever seen.
This is an infra-red camera, so it's able to see all the hot stuff, which the big cameras can't see.
When this thing erupts, you can feel the shockwaves hitting you.
That thing is on top of a chamber of molten rock three kilometres wide and three kilometres deep.
I mean, it's just terrifying.
But to be absolutely honest with you, I'm actually feeling quite apprehensive, because this is a force that just is too immense to even think about.
You couldn't speed away from this in a hurry.
You'd be toast.
Good grief! Four hours on, and still no sign of the unknown mammal.
I don't often feel as if I've got the upper hand on an animal.
I think in this case I do, because I can see the monitor of the camera that's looking straight down.
So it gives me a bit of warning.
If he's a bit agitated from me looking down into that tree stump earlier on, he might just shoot out and I won't get any shots of him, but at least that camera up there, I can see the moment he starts to climb up.
This is really exciting, because other than just two little eyes, I just don't know what's in there.
It's a mammal of some sort, but who knows what it is? OK, he's starting to come, he's starting to come.
Great! Come on, out you come.
Come on, come on.
We're evacuating camp, and in a hurry.
And with very good reason.
Show me, show me, show me.
That one? That's one of the bombs that came out.
We thought we were safe here, we were a long way away, and it landed here.
That would have killed you instantly.
So I think we should all go now.
George's mission has come to an abrupt end.
In the calm of the jungle night, Gordon's patience could be rewarded.
He's going to come out, he will.
Come on, come on.
Here he comes, looks like a mole.
I know it's not a mole, but it's very hard to tell what he is.
Oh, God, my heart is beating out of my chest, come on! Please, please, please oh, there he is, there he is, there he is! You little beauty! What is that? Gosh.
I haven't got a clue what he is.
That's weird.
That is so weird.
OK, if he just comes out a bit more, I can get an idea of his body shape, but you can see his teeth his eyes are shining like that because of this infrared light bouncing straight back at me.
What a pretty animal.
OK, out you come, come on, come on, please, just come out.
Gosh, look at that.
Oh, gosh, no, I think he's trying to go off - he's going to try and grab a limb and go off, oh, there.
There could well be new species living here in the crater, and my job is to get shots of them, and let Kris try and identify them.
Whatever it is, it appears to have no fear of people.
If unique to the crater, it would help prove just how special the jungles of Bosavi are.
Whilst Gordon is deep in the jungle, Steve is on the river.
No-one knows what may lurk here at night.
Eughh! Look! Whoa! They've been roosting just in the branches above us so as we've come across with our torches and lights, it's given them a shock.
Steve is being mobbed by torrent flycatchers, birds found only in New Guinea.
Eughh! It just flew right into my face.
It may be wet, but no-one imagined there would be ducks in the jungle.
Now that is something I really didn't expect to see! Salvadori's teal - unique to the mountain rivers of New Guinea.
They almost look like they're just enjoying the rapids! That is a glorious looking little tree frog.
Off he goes.
Wow! These are actually torrent breeding frogs, so they love breeding in fast-flowing water like this.
Let's see if we can get a glance at what makes this frog really special.
That eyelid is laced through with a network of veins and it's absolutely beautiful.
He's got a face that you just can't help but love, and you know that any second, although he's sitting comfortably on my finger here, he could, without a single warning, just spring away and be gone.
Come on, go and find yourself a girlfriend.
Not the ear! Mount Bosavi is so large it generates its own weather.
For much of the night it's been raining, and the sleeping area is flooding.
There's no respite from the mud.
And it's tinned spaghetti for breakfast, again.
Kris and Steve are reviewing Gordon's footage from last night, in the hope it's the mystery cuscus they've been looking for.
Those big beautiful eyes.
Yeah.
It's small little ears, they're in the fur.
And light belly here.
Light belly.
I reckon that is our cuscus.
You think? I reckon it is.
I reckon it is, it's dark.
So this could be the animal that that skull belongs to.
This could be the mysterious Bosavi cuscus.
This could definitely be.
Wow.
So what we really need now is to actually catch one of these in our traps.
Then we'll get a feel for the colour, we'll see what it really looks like, and if that really is a good match for the animal's teeth that we've been looking at that are so distinctive.
Yeah.
This could be really exciting now, I think this is our animal.
It looks like a major new discovery, but pictures alone are not scientific proof.
To get that, they'll need to catch one in the few days that are left.
Bosavi's forests extend right up to the summit.
A vertical kilometre above Steve and Gordon, the jungle is much wetter.
George is joining the team on the mountain.
His mission to explore the cloud forest clinging to the summit.
Being one of the world's leading experts on insects, if there's anything unusual, he'll find it.
This volcano is just like like an island in the sky.
I mean, it's 9,000 feet above sea level.
Look at that wall! God, that is unbelievable.
But as you can see, the weather's really very cloudy.
It's amazing how it changes incredibly heavy rain, very dark, and then just a little a little gap in the cloud cover there.
So it's touch and go whether we'll be able to land there.
We're gonna make it.
We're clear to land, we're clear to land.
Oh yeah, we're here! Fantastic.
This precarious cliff edge will be George's camp for the next couple of days.
A thousand metres below him, they're on the look out for new animals.
Top of their list - the unknown cuscus.
They search every hole Every nook and every cranny Mate, this place is leech central.
.
.
By day .
.
And by night.
Camera traps are set.
Leech.
Any mammals that come in here they'll try and get on to them, including humans.
A face only a mother could love.
The team use every piece of kit available.
Lots of insect noise, some frogs.
Some weird stuff, I don't know what it is.
It's incredible that a frog this tiny size, I mean it's no bigger than the end of my thumb, can make a noise that loud, just puffing itself up like a great big balloon and then squeezing all the air out.
But this jungle is so dense and so steep, it's hard to find anything.
On the summit, George is out exploring the peculiar mountain moss forest for the first time.
He's stepped into another world.
It's like Lord Of The Rings habitat.
You'd expect orcs and elves appearing any minute.
The whole forest is just humid, 100% humidity all the time, and this may look like solid ground, but it's not.
Look, I can go through there and beyond.
I can put my hand I can go, probably, I can put my whole arm right through up to the hilt and that's just roots and soil and space, and that's what we're standing on.
The whole thing is just a sort of a mirage, almost, of plants and soil, but the soil's really interesting because the soil isn't just here, it actually occurs up on the plants as well.
So it's actually aerial soil - all of this is just growing on a single thin branch.
It's a huge carpet of moss and soil.
It's almost like a different world.
I haven't seen that one before.
Absolutely amazing.
I mean, decay just brings fungi, bacteria, mosses - just everything is feeding off what's here.
And look at that, that is the most exquisite tiny fungus growing on a dwarf bamboo, and it is just incredible.
Ooh, look, look! Good God, look at that! I just saw that there in the ground.
It's huge! This is a flatworm.
Well, that's exactly the sort of animal you'd expect to find in this constantly wet environment.
Flatworms come in all shapes and sizes that's the underside but I have never seen a flatworm this big before.
It's absolutely amazing.
Tiny little head end, that's the head end there.
This habitat is incredibly special, because there are animals and plants here, orchids and insects and higher animals you won't find anywhere else in the world.
But also because it occupies a very, very small area and with increased global warming, that area will get smaller and smaller and smaller and eventually it'll all be gone.
In the crater, one of the trackers has returned to camp with a wild animal, and it's totally trusting.
Oh, wow! Oh, my goodness, he's absolutely beautiful.
Come on little fella.
I think it's our guy.
I'm going to look in his mouth in a bit and we'll know from his teeth but this looks right on.
This is a dark-furred cuscus, it's a montane cuscus.
It's very much like the skull I suspected.
The skull was similar to a different species called the silky cuscus, and the body is too, you can feel that silky fur.
It's really, really thick.
I guess this has adapted to living in a mountain environment.
That's right.
He seems to like you.
He's got a very, very strong, but not actually unpleasant, smell.
But it does hit you.
This is the mammal that Gordon filmed emerging from the tree stump.
I'm calling this the Bosavi cuscus, because I really think it has a lot of distinctive features.
We're gonna find out more as we look closer, but I just I can't even begin to describe how it feels to have an animal in my hands that is this beautiful and, in all probability, has never been seen before by science.
I think what we have is a cuscus that long ago has been isolated on this volcano and has just not been able to have any contact with any of its relatives and has become something here in isolation that is unique to Bosavi.
He's totally chilled out.
He's got no idea quite how important he is.
So gorgeous.
Yeah! Little guy! You're a major scientific discovery.
How about that? I travel the world looking for new species in many different places and we find new mammals, it still does happen, but so many of them, most of them are things like bats and rodents, and to find something, a marsupial, an animal that's this size is really exciting, it's a cause for a major celebration.
Crack open the champagne, or crack open the bully beef! It's a brand new sub-species of cuscus, and Bosavi is its only home.
If these jungles are logged, we'll lose animals like this forever.
Both on the summit and in the crater, the rainforest is undisturbed by humans.
Animals are remarkably naive.
Almost incredibly, I'm about six feet away from an ornate fruit-dove.
You couldn't normally get this close to birds, especially on the nest.
She's camouflaged to perfection against the foliage - green with a little bit of blue at the back, this ochre-y head and a white bit underneath.
She's being very vigilant, she's watching me very carefully and turning her head from side to side, very slowly.
Amazing.
Thing about animals here is that they really aren't experienced, they don't know what humans are all about yet, which may be a problem for them.
The history of humans has been that if animals are edible or hazardous, they usually end up dead.
In the depths of the crater, it's raining again.
It's been a long, hard expedition.
Exhaustion and illness are setting in.
There's been an outbreak of intestinal worms in the camp, so we're all taking these worming tablets which will pretty much kill everything we've got in our guts.
Makes you feel really run down, but this tablet just kills everything.
Leeches are infesting camp.
Gordon and Kris take time to see if anything strange has been caught on the camera traps.
Let's have a look.
OK, that's me still me.
Kris is one of the few people in the world who can distinguish what's just rare from what's totally new.
Oh! Is that a tree kangaroo? It's not a tree kangaroo, but it is a kangaroo.
So it's a wallaby.
Moves along the forest floor here in the crater.
See what else we've got.
I've got a good feeling about this one.
They scan hundreds of images, and eventually, they strike gold.
Wow! Have a look at that.
What is that? That long, naked tail, what do you think that is? It just looks like an enormous rat.
Yes, it's a giant rat, it's a woolly giant rat.
Jeez, it must be that size without its so that size with its tail? Exactly, almost a metre long.
Seriously? And this camera trap proves that an animal like that is here.
To get conclusive evidence whether this is a new species, you need more than a photograph.
This black and white photograph isn't going to do it.
We're going to have to see if we can find this animal in the flesh, hold it, see what this animal is.
But just using your experience, this could be a new species? There's no question in my mind this is a giant woolly rat, and I suspect Bosavi has its own kind.
Wow, that would be some amazing find.
No-one imagined just how rich this mountain would turn out to be.
In the weird moss forest that clings to the rim of the crater, George is setting a trap.
It's carefully positioned, right on the cliff edge.
Once night falls, a high-powered light bulb will be switched on to attract insects to the sheet.
And that's going to be hopefully, it's going to be heaving with bugs.
Down below, the hunt is on for the giant woolly rat.
Gordon and Steve head off in opposite directions.
They will search all night if they have to.
Somewhere out there in the darkness is one of the world's biggest rats.
At night, the jungle has its own special magic.
This tree is covered in bracket fungus, and you can see all the tiny little spores being discharged, it makes it look as if they're actually steaming.
In the early hours, Kris finds another animal with no fear of humans.
It looks like a giant hamster, but it's a painted ringtail.
Oh, he's absolutely gorgeous! Not a new species, but definitely one of the most beautiful animals that lives in this forest.
Gosh, he really is.
The fur is just exquisite.
It is just so dense and so soft.
You can see at night time this place just comes alive.
We've done so much walking about this forest finding nothing, and you only have to find something like this and it makes it all worthwhile.
You forget all that misery and all that hardship.
On the cliff edge, George can hardly believe his eyes.
I'm just overwhelmed.
I never imagined I'd see such a diversity of moth.
I mean, some of these things I've never seen before in my life.
The variety of moths here is absolutely staggering! There's geometrids, hawkmoths, there's fruit piercing moths, and it's raining, it's tipping it down! This shouldn't be happening, and these bulbs only work in a radius of about 200 yards.
All this has come from a 200 yard radius to this bulb.
Can you imagine how rich this forest actually is? Almost beyond my understanding.
Look at that.
I'm absolutely incredulous.
My God, look at it! Look at that one, that brassy gold colour.
In the crater, Steve's searching for the giant rat, but he's discovered a tarantula.
Look at that! The way he's tilted back there, you can see he's rocked back in order to bring those fangs into position so he can bring down the entire bodyweight, plunging those fangs into whatever it is that's annoying him.
Come on then.
Now don't go, don't go.
I do have to be careful here, I'd be a lot more ambitious if I knew what it was and if we were in a less remote environment.
But to get bitten or stung by something like this out here .
.
could be really sketchy.
I have never been anywhere where I've seen the diversity of moths that I'm seeing here.
If you'd told me, I wouldn't have believed you, but it's here.
This one! That's a different hawkmoth.
That's a different one come in now, just now.
V- shaped wings, very fast flyers, really strong moths.
Fantastic colouration there.
Oh, look now, there's a hawkmoth too.
Now, I've never seen that one before.
What percentage of these will be new? It could easily be a quarter, it could easily be a quarter of them.
This is a very interesting moth.
It's called an arctiid moth and when it's annoyed, it produces very horrible-smelling fluid from the thorax.
There, see that? Look at that! That is amazing! What a defence.
And that tastes really foul.
Yuk, yuk.
Even if I'd had to walk up here on my hands and knees, it would have been worth it for this.
This one hour of moth mayhem.
A haul of unique creatures like this proves Bosavi's forests are priceless.
Honestly! Gordon gets a shout from a tracker.
Oh, my word, have a look at this! Oh, gosh, that is the biggest rat I have ever seen.
That is a murid rat, a true rat, the same family as the rats you find in cities and sewers.
You've got a big smile on your face.
The reason I'm smiling is because this is absolutely a new species.
This is something that doesn't have a scientific name.
This is one of the largest rats in the world, and here we are, holding it.
I just think it's an amazing creature, found nowhere else on the entire planet.
That is such a huge deal.
And this animal is so chilled out, look at him, he's just grooming.
You can tell it's a rat but yet it looks just so different from any rat you've ever seen, right? Yeah.
I had a cat, and the cat was about the same size as this rat.
Any cat that you buy to catch rats is going to run a mile from something like this.
Mount Bosavi's such a big mountain, it's largely unexplored, it's so isolated that truly, some of the things we are finding are new species and are spectacular new species.
Big rats, cuscus, fantastic animals.
It gave me the heebie-jeebies, the thought of a giant rat and I've been going down the holes in hollow trees looking for big things, and it's actually kept me awake at night and here he is, he's just oh, he's like a little puppy.
New species of giant woolly rat! Yeah.
No! That's unbelievable.
Or are you just making it up? No, no, we got it, we got it, yeah.
God, it was great, so great.
The biggest rat in the world.
Was it in a trap or was it? No, just running about the forest, tame as anything.
That's incredible.
It's time to pack up and collect George from the summit.
As I stand here, just about to be whisked away by this helicopter, I realise that my grandchildren may not ever be able to see this sort of habitat or the animals and plants that live here.
It could all be gone.
Now all their findings will be brought together and presented to the outside world.
With the help of a remarkable tribe, they've found hundreds of spectacular creatures.
He is just a parrot in miniature.
That is absolutely gorgeous! They've discovered over 40 new species, from exquisite geckos to magical moths and bizarre frogs.
And they've made major scientific discoveries creatures with no fear of people.
Oh, he's like a little puppy! Mammals that no-one knew existed.
Wow! It's so incredibly rare that new species of mammal are found around the world these days.
This has got to be one of the most incredible moments of my life.
All of this on one amazing mountain.
The hope is that Mount Bosavi, once a forgotten corner, will now become known around the world and protected as a unique rainforest of global importance.
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