The last hidden world, China.
For centuries, travellers to China have
told tales of magical landscapes
and surprising creatures.
Chinese civilization is the world's oldest
and today, its largest,
with well over a billion people.
It's home to more than 50 distinct ethnic groups
and a wide range of traditional lifestyles,
often in close partnership with nature.
We know that China faces immense
social and environmental problems.
But there is great beauty here, too.
China is home to the world's highest mountains,
vast deserts ranging from searing hot
to mind-numbing cold.
Steaming forests harbouring rare creatures.
Grassy plains beneath vast horizons.
And rich tropical seas.
Now for the first time ever,
we can explore the whole of this great country,
meet some of the surprising
and exotic creatures that live here
and consider the relationship
of the people and wildlife of China
to the remarkable landscape in which they live.
This is Wild China.
Our exploration of China
begins in the warm, subtropical south.
On the Li River, fishermen and birds
perch on bamboo rafts,
a partnership that goes back more than a thousand years. This scenery is known throughout the world,
a recurring motif in Chinese paintings.
And a major tourist attraction.
The south of China is a vast area,
eight times larger than the UK.
It's a landscape of hills but also of water.
It rains here for up to 250 days a year,
and standing water is everywhere.
In the floodplain of the Yangtze River,
black-tailed godwits probe the mud in search of worms. But isn't just wildlife that thrives in this environment. The swampy ground provides ideal conditions
for a remarkable member of the grass family. Rice.
The Chinese have been cultivating rice
for at least 8,000 years. It has transformed the landscape.
Late winter in southern Yunnan is a busy time for local farmers as they prepare the age-old paddy fields
ready for the coming spring.
These hill slopes of the Yuanyang County
plunge nearly 2,000 metres
to the floor of the Red River valley.
Each contains literally thousands of stacked terraces
carved out by hand using basic digging tools.
Yunnan's rice terraces are among
the oldest human structures in China.
Still ploughed, as they always have been,
by domesticated water buffaloes,
whose ancestors originated in these very valleys.
This man-made landscape is one of the most
amazing engineering feats of pre-industrial China.
It seems as if every square inch of land
has been pressed into cultivation.
As evening approaches, an age-old ritual unfolds.
It's the mating season and male paddy frogs are competing for the attention of the females.
But it doesn't always pay
to draw too much attention to yourself.
The Chinese pond heron is a pitiless predator.
Even in the middle of a ploughed paddy field,
nature is red in beak and claw.
This may look like a slaughter
but as each heron can swallow only one frog at a time,
the vast majority will escape
to croak another day.
Terraced paddies like those of the Yuanyang County
are found across much of southern China.
This whole vast landscape is dominated by rice cultivation.
In hilly Guizhou Province,
the Miao minority have developed a remarkable rice culture. With every inch of fertile land given over to rice cultivation, the Miao build their wooden houses
on the steepest and least productive hillsides.
In Chinese rural life, everything has a use.
Dried in the sun,
manure from the cow sheds will be used as cooking fuel.
It's midday, and the Song family
are tucking into a lunch of rice and vegetables.
Oblivious to the domestic chit-chat,
Granddad Gu Yong Xiu has serious matters on his mind. Spring is the start of the rice growing season.
The success of the crop will determine
how well the family will eat next year,
so planting at the right time is critical.
The ideal date depends
on what the weather will do this year,
never easy to predict.
But there is some surprising help at hand.
On the ceiling of the Songs' living room,
a pair of red-rumped swallows,
newly arrived from their winter migration,
is busy fixing up last year's nest.
In China, animals are valued
as much for their symbolic meaning
as for any good they may do.
Miao people believe that swallow pairs
remain faithful for life,
so their presence is a favour and a blessing,
bringing happiness to a marriage
and good luck to a home.
Like most Miao dwellings,
the Songs' living room windows
look out over the paddy fields.
From early spring,
one of these windows is always left open
to let the swallows come and go freely.
Each year, granddad Gu notes
the exact day the swallows return.
Miao people believe the birds' arrival
predicts the timing of the season ahead.
This year, they were late.
So Gu and the other community elders have agreed that rice planting should be delayed accordingly.
As the Miao prepare their fields for planting,
the swallows collect mud to repair their nests
and chase after insects
across the newly ploughed paddies.
Finally, after weeks of preparation,
the ordained time for planting has arrived.
But first the seedlings must be
uprooted from the nursery beds
and bundled up ready
to be transported to their new paddy
higher up the hillside.
All the Songs' neighbours have turned
out to help with the transplanting.
It's how the community has always worked.
When the time comes, the Songs will return the favour. While the farmers are busy in the fields,
the swallows fly back and forth
with material for their nest.
Many hands make light work.
Planting the new paddy takes little more than an hour. Job done, the villagers can relax, at least until tomorrow.
But for the nesting swallows,
the work of raising a family has only just begun.
In the newly planted fields, little egrets hunt for food.
The rice paddies harbour tadpoles, fish and insects
and the egrets have chicks to feed.
This colony in Chongqing Province was established in 1996, when a few dozen birds built nests in the bamboo grove behind Yang Guang village.
Believing they were a sign of luck,
local people initially protected the egrets and the colony grew. But their attitude changed when the head of the village fell ill. They blamed the birds and were all set to destroy their nests, when the local government stepped in to protect them. Bendy bamboo may not be the safest nesting place,
but at least this youngster won't end up as someone's dinner. These chicks have just had an eel delivered by their mum, quite a challenge for little beaks.
Providing their colonies are protected,
wading birds like egrets are among the few wild creatures which benefit directly from intensive rice cultivation. Growing rice needs lots of water.
But even in the rainy south,
there are landscapes where water is surprisingly scarce.
This vast area of southwest China,
the size of France and Spain combined,
is famous for its clusters of conical hills,
like giant upturned egg cartons,
separated by dry empty valleys.
This is the karst, a limestone terrain
which has become the defining image of southern China. Karst landscapes are often studded with rocky outcrops, forcing local farmers to cultivate tiny fields.
The people who live here are among the poorest in China.
In neighbouring Y unnan Province,
limestone rocks have taken over entirely.
This is the famous Stone Forest,
the product of countless years of erosion,
producing a maze of deep gullies and sharp-edged pinnacles. Limestone has the strange property
that it dissolves in rainwater.
Over many thousands of years water has corroded its way deep into the heart of the bedrock itself.
This natural wonder is a famous tourist spot,
receiving close to two million visitors each year.
The Chinese are fond of curiously-shaped rocks
and many have been given fanciful names.
No prizes for guessing what this one is called!
But there's more to this landscape than meets the eye.
China has literally thousands
of mysterious caverns concealed beneath
the visible landscape of the karst.
Much of this hidden world
has never been seen by human eyes
and is only just now being explored.
For a growing band of intrepid young Chinese explorers, caves represent the ultimate adventure.
Exploring a cave is like taking a journey through time. Ajourney which endless raindrops will
have followed over countless centuries.
Fed by countless drips and trickles,
the subterranean river carves ever deeper into the rock. The cave river's course is channeled
by the beds of limestone.
A weakness in the rock can allow the river
to increase its gradient and flow-rate,
providing a real challenge for the cave explorers.
The downward rush is halted
when the water table is reached.
Here the slow-flowing river carves
tunnels with a more rounded profile.
This tranquil world is home to specialised cave fishes, like the eyeless golden barb.
China may have more unique
kinds of cave-evolved fishes than anywhere else on earth. Above the water table, ancient caverns abandoned
by the river slowly fill up with stalactites and stalagmites. Stalactites form as trickling water
deposits tiny quantities of rock
over hundreds or thousands of years.
Stalagmites grow up where
lime-laden drips hit the cave floor.
So far, only a fraction of China's caves
have been thoroughly prospected
and cavers are constantly discovering
new subterranean marvels,
many of which are subsequently
developed into commercial show caves.
Finally escaping the darkness,
the cave river and its human explorers
emerge in a valley far from where their journey began. For now, the adventure is over.
Rivers which issue from caves
are the key to survival in the karst country.
This vertical gorge in Guizhou Province
is a focal point for the region's wildlife.
This is one of the world's rarest primates,
Francois' langur. In China they survive in just two southern provinces, Guizhou and Guangxi, always in rugged limestone terrains. Like most monkeys, they are social creatures
and spend a great deal of time grooming each other. Langurs are essentially vegetarian
with a diet of buds, fruits and tender young leaves.
Babies are born with ginger fur,
which gradually turns black from the tail end.
Young infants have a vice-like grip,
used to cling on to mum for dear life.
As they get older, they get bolder and take more risks. Those that survive spend a lot of time travelling.
The experienced adults know exactly
where to find seasonal foods in different parts of their range. In such steep terrain,
travel involves a high level of climbing skill.
These monkeys are spectacularly good rock climbers
from the time they learn to walk.
In langur society, females rule the roost
and take the lead when the family is on the move.
One section of cliff oozes a trickle of mineral-rich water which the monkeys seem to find irresistible.
These days there are few predators in the Mayanghe Reserve which might pose a risk to a baby monkey.
But in past centuries, this area of south China
was home to leopards, pythons and even tigers.
To survive dangerous night prowlers,
the langurs went underground, using their rock-climbing skills to seek shelter in inaccessible caverns.
Filmed in near darkness using a night vision camera,
the troop clambers along familiar ledges
worn smooth by generations before them.
During cold winter weather,
the monkeys venture deeper underground
where the air stays comparatively warm.
At last, journey's end.
A cosy niche beyond the reach
of even the most enterprising predator.
But it's not just monkeys that find shelter in caves.
These children are off to school.
In rural China that may mean a long trek each morning, passing through a cave or two on the way.
But not all pupils have to walk to school.
These children are boarders.
As the day pupils near journey's end,
the boarders are still making breakfast.
In the schoolyard, someone seems
to have switched the lights off.
But this is no ordinary playground, and no ordinary school.
It's housed inside a cave!
A natural vault of rock keeps out the rain
so there's no need for a roof on the classroom. Zhongdong cave school is made up of six classes,
with a total of 200 children.
As well as the school, the cave houses 18 families, together with their livestock.
These could be the only cave-dwelling cows on earth. With schoolwork over, it's playtime at last.
In southern China, caves aren't just used for shelter, they can be a source of revenue for the community. People have been visiting this cave for generations. The cave floor is covered in guano,
so plentiful that 10 minutes' work
can fill these farmer's baskets.
It's used as a valuable source of fertilizer.
A clue to the source of the guano can
be heard above the noise of the river.
The sound originates high up in the roof of the cave. The entrance is full of swifts.
They're very sociable birds.
More than 200,000 of them share this cave
in southern Guizhou Province,
the biggest swift colony in China.
These days, Chinese house swifts
mostly nest in the roofs of buildings,
but rock crevices like these were their original home, long before houses were invented.
Though the swifts depend on the cave for shelter,
they never stray further than the limits of daylight,
as their eyes can't see in the dark.
However, deep inside the cavern,
other creatures are better equipped for subterranean life.
A colony of bats is just waking up,
using ultrasonic squeaks to
orientate themselves in the darkness.
Night is the time to go hunting.
Rickett's mouse-eared bat is the only bat in Asia
which specialises in catching fishes,
tracking them down from
the sound reflection of ripples on the water surface. This extraordinary behaviour was only discovered
in the last couple of years,
and has never been filmed before.
If catching fish in the dark is impressive,
imagine eating a slippery minnow with
no hands while hanging upside down.
Dawn over the karst hills of Guilin.
These remarkable hills owe their peculiar shapes to the mildly acid waters of the Li River,
whose meandering course over eons of time
has corroded away their bases
until only the rocky cores remain.
The Li is one of the cleanest rivers in China,
a favourite spot for fishermen with their trained cormorants. The men, all called Huang, come from the same village. Now in their 70s and 80s,
they've been fishermen all their lives.
Before they release the birds,
they tie a noose loosely around the neck
to stop them swallowing any fish they may catch.
Chanting and dancing,
the Huangs encourage their birds to take the plunge. Underwater, the cormorant's hunting instinct kicks in, turning them into fish-seeking missiles.
Working together, a good cormorant team
can catch a couple of dozen decent-sized fish in a morning. The birds return to the raft with their fish
because they've been trained to do so.
From the time it first hatched,
each of these cormorants has been reared
to a life of obedience to its master.
The birds are, in effect, slaves.
But they're not stupid.
It's said that cormorants can keep a tally of the fish they catch, at least up to seven.
So unless they get a reward now and then
they simply withdraw their labour.
The fishermen, of course, keep the best fish for themselves. The cormorants get the leftover tiddlers.
With its collar removed, the bird at last can swallow its prize. Best of all, one it isn't meant to have!
These days, competition from modern fishing techniques means the Huangs can't make a living
from traditional cormorant fishing alone.
And this 1,300-year-old tradition
is now practised mostly to entertain tourists.
But on Caohai Lake in nearby Guizhou Province,
an even more unusual fishing industry is alive and well. Geng Zhong Sheng is on his way
to set out his nets for the night.
Geng's net is a strange tubular
contraption with a closed-off end.
More than a hundred fishermen
make their living from the lake.
Its mineral-rich waters are highly productive,
and there are nets everywhere.
The next morning, Geng returns
with his son to collect his catch.
At first sight, it looks disappointing.
Tiny fishes, lots of shrimps, and some wriggling bugs. Geng doesn't seem too downhearted.
The larger fish are kept alive, the only way
they'll stay fresh in the heat.
Surprisingly, some of the bugs are also
singled out for special treatment.
They're the young stage of dragonflies,
predators that feed on worms and tadpoles.
Nowhere else in the world are
dragonfly nymphs harvested like this.
Back home, Geng spreads his catch
on the roof to dry.
This being China, nothing edible will be wasted.
There's a saying in the far south,
"We will eat anything with legs except a table,
"and anything with wings except a plane."
Within a few hours, the dried insects
are ready to be bagged up and taken to market.
It's the dragonfly nymphs that fetch the best price. Fortunately, Caohai's dragonflies
are abundant and fast-breeding.
So Geng and his fellow fishermen
have so far had little impact on their numbers.
But not all wildlife is so resilient.
This Buddhist temple near Shanghai has
an extraordinary story attached to it.
In May 2007, a Wild China camera team
filmed this peculiar Swinhoe's turtle
in the temple's fish pond.
According to the monks,
the turtle had been given to the temple
during the Ming dynasty, over 400 years ago.
It was thought to be the oldest animal on earth.
Soft-shelled turtles are considered
a gourmet delicacy by many Chinese,
and when it was filmed,
this was one of just three
Swinhoe's turtles left alive in China,
the rest of its kind having been rounded up and eaten. Sadly, just a few weeks after filming,
this ancient creature died.
The remaining individuals of its species
are currently kept in separate zoos
and Swinhoe's turtle is now reckoned extinct in the wild. In fact, most of the 25 types of freshwater turtles in China are now vanishingly rare.
The answer to extinction is protection. And there is now a growing network of nature reserves throughout southern China.
Of these, the Tianzi Mountain Reserve
at Zhangjiajie is perhaps
the most visited by Chinese nature lovers,
who come to marvel at the gravity-defying landscape
of soaring sandstone pinnacles.
Winding between Zhangjiajie's peaks,
crystal clear mountain streams
are home to what is perhaps China's strangest creature.
This bizarre animal is a type of newt,
the Chinese giant salamander.
In China it is known as the baby fish
because when distressed
it makes a sound like a crying infant.
It grows up to a metre and a half long,
making it the world's largest amphibian.
Under natural conditions,
a giant salamander may live for decades.
But like so many Chinese animals,
it is considered delicious to eat.
Despite being classed as a protected species,
giant salamanders are still illegally sold for food
and the baby fish is now rare and endangered in the wild. Fortunately, in a few areas like Zhangjiajie,
giant salamanders still survive under strict official protection. The rivers of Zhangjiajie flow
north east into the Yangtze floodplain,
known as The Land of Fish and Rice.
On an island in a lake in Anhui Province,
a dragon is stirring.
This is the ancestral home of China's largest and rarest reptile, a creature of mystery and legend.
Dragon eggs are greatly prized.
These babies need to hatch out quick!
It would seem someone is on their trail.
For a helpless baby reptile,
imprisoned in a leathery membrane inside a chalky shell,
the process of hatching is a titanic struggle.
And time is running out.
It's taken two hours
for the little dragon to get its head out of the egg.
It needs to gather its strength now, for one final, massive push. Free at last, the baby Chinese alligators
instinctively head upwards towards the surface of the nest and the waiting outside world.
But the visitors are not what they seem.
She Shizhen and her son live nearby.
She has been caring for her local alligators for over 20 years,
so she had a fair idea
when the eggs were likely to hatch.
Back home, she's built a pond surrounded
by netting to keep out predators,
where her charges will spend the next six months until they're big enough to fend for themselves. For the past 20 years,
small-scale conservation projects like this
are all that have kept China's
150 wild alligators from extinction.
Just south of the alligator country,
dawn breaks over a very different landscape.
The 1,800-metre-high granite peaks
of the Huangshan or Yellow Mountain.
To the Chinese, Huangshan's pines epitomise
the strength and resilience of nature.
Some of these trees are thought
to be over 1,000 years old.
Below the granite peaks,
steep forested valleys shelter surprising inhabitants. Huangshan macaques, rare descendants of
the Tibetan macaques of western China,
are unique to these mountain valleys
where they enjoy strict official protection.
After a morning spent in the treetops,
the troop is heading for the shade of the valley.
A chance for the grown-ups to escape the heat
and maybe pick up a lunch snack from the stream. As in most monkey societies,
social contact involves a lot of grooming. Grooming is all very well for grown-ups,
but young macaques have energy to burn.
Like so much monkey business,
what starts off as a bit of playful rough-and-tumble, soon begins to get out of hand.
The alpha male has seen it all before.
He's not in the least bothered.
But someone, or something, is watching,
with a less than friendly interest.
The Chinese moccasin is
an ambush predator with a deadly bite.
This is one of China's largest
and most feared venomous snakes.
But the monkeys have lived alongside
these dangerous serpents for thousands of years. They use this specific alarm call to warn each other whenever a snake is spotted.
Once its cover is blown, the viper poses
no threat to the monkeys, now safe in the treetops. And life soon returns to normal.
By late summer,
the rice fields of southern China have turned to gold.
The time has come to bring in the harvest.
Nowadays, modern high-yield strains
are grown throughout much of the rice lands,
boosted by chemical fertilizers
and reaped by combine harvesters.
This is the great rice bowl of China,
producing a quarter of the world's rice.
Insects, stirred up by the noisy machines,
are snapped up by gangs of red-rumped swallows,
including this year's youngsters,
who will have fledged several weeks ago.
This could be their last good feast
before they head south for the winter.
Mechanized farming works best
in the flat-bottomed valleys of the lowlands.
To the south, in the terraced hills of Zhejiang Province,
an older and simpler lifestyle persists.
It's 7:00 in the morning
and Longxian's most successful businessman is off to work. In the golden terraces surrounding the village
the ears of rice are plump and ripe for harvesting.
But today, rice isn't uppermost in Mr Yang's mind.
He has bigger fish to fry.
Further up the valley, the harvest has already begun.
Yang's fields are ripe, too,
but they haven't been drained yet.
That's because for him, rice is not the main crop.
The baskets he's carried up the hillside
give a clue to Yang's business.
But before he starts work,
he needs to let some water out of the system.
As the water level drops, the mystery is revealed.
Golden carp.
Longxian villagers discovered
the benefits of transferring wild caught carp
into their paddy fields long ago.
The tradition has been going on here for at least 700 years. As the water level in the paddy drops,
bamboo gates stop the fish escaping.
The beauty of this farming method is that it delivers two crops from the same field at the same time.
Fish and rice.
Smart ecology like this is what enables China
to be largely self-sufficient in food, even today.
Back in the village, Yang has his own smokehouse
where he preserves his fish ready for market.
Longxian carp have unusually soft scales
and a very delicate flavour,
perhaps as a result of the local water.
Meanwhile, outside the smokehouse,
there's something fishy going on.
To mark the harvest,
the village is staging a party.
Children from Longxian school
have spent weeks preparing for their big moment. Everyone from the community is here to support them. The rice growing cycle is complete.
By November,
northern China is becoming distinctly chilly.
But the south is still relatively warm and welcoming. Across the vast expanse of Poyang Lake,
the birds are gathering.
Tundra swans are long-distance migrants
from northern Siberia.
To the Chinese,
they symbolise the essence of natural beauty.
The Poyang Lake Nature Reserve offers winter refuge to more than a quarter of a million birds
from more than 100 species,
creating one of southern China's
finest wildlife experiences.
The last birds to arrive at Poyang
are those which have made
the longest journey to get here,
all the way from the Arctic coast of Siberia.
The Siberian crane,
known in China as the white crane,
is seen as a symbol of good luck.
Each year,
almost the entire world population
of these critically endangered birds
make a 9,000-kilometre roundtrip
to spend the winter at Poyang.
Like the white cranes,
many of south China's unique animals
face pressure from exploitation
and competition with people over space and resources. But if China is living proof of anything,
it is that wildlife is surprisingly resilient.
Given the right help,
even the rarest creatures can return from the brink.
If we show the will,
nature will find the way.
Beneath billowing clouds,
in China's far southwestern Yunnan province,
lies a place of mystery and legend.
Of mighty rivers and some of the oldest jungles in the world. Here, hidden valleys nurture strange and unique creatures, and colourful tribal cultures.
Jungles are rarely found this far north of the tropics.
So, why do they thrive here?
And how has this rugged landscape come to harbour
the greatest natural wealth in all China?
In the remote southwest corner of China,
a celebration is about to take place.
Dai people collect water
for the most important festival of their year.
The Dai call themselves the people of the water.
Yunnan's river valleys
have been their home for over 2,000 years.
By bringing the river water to the temple,
they honour the two things holiest to them -
Buddhism and their home.
The Dai give thanks for the rivers and fertile lands
which have nurtured their culture.
Though to some it might seem just an excuse
for the biggest water fight of all time.
Dai lives are changing as towns get bigger and modernized but the Water Splashing Festival is still celebrated by all. The rivers which lie at the heart of Dai life and culture
flow from the distant mountains of Tibet,
southward through central Y unnan in great parallel gorges. The Dai now live in the borders of tropical Vietnam and Laos, but their legends tell of how their ancestors came here
by following the rivers from mountain
lands in the cold far north.
Lying at the far eastern end of the Himalayas,
the Hengduan mountains form
Yunnan's northern border with Tibet.
Kawakarpo, crown of the Hengduan range,
is a site of holy pilgrimage.
Yet, its formidable peak remains unconquered.
Yunnan's mountains are remote, rugged and inaccessible. Here the air is thin
and temperatures can drop below minus 40 degrees.
This is home to an animal that's found nowhere else on Earth. The Yunnan snub-nosed monkey.
It's found only in these few isolated mountain forests.
No other primate lives at such high altitudes
but these are true specialists.
These ancient mountain dwellers have inspired legends. Local Lisu people consider them their ancestors,
calling them "the wild men of the mountains".
During heavy snowfalls,
even these specialists cannot feed.
It seems a strange place for a monkey.
Between snows, the monkeys waste
no time in their search for food.
At this altitude,
there are few fruits or tender leaves to eat.
90% of their diet is made up of the
fine dry wisps of a curious organism.
Half fungus, half plant - it's lichen.
How have monkeys,
Normally associated with lowland jungle,
come to live such a remote mountain existence?
This is not the only remarkable animal found within these isolated high peaks.
A Chinese red panda.
Solitary and quiet,
it spends much of its time in the tree tops.
Despite its name,
the red panda is only a very distant
relative of the giant panda.
It's actually more closely related to a skunk.
But it does share the giant panda's taste for bamboo. Southwest China's red pandas
are known for their very strong facial markings
which distinguish them from red pandas
found anywhere else in the Himalayas.
Like the monkeys, they were isolated in these high forests when the mountains quite literally rose beneath them
in the greatest mountain-building
event in recent geological history.
Over the last 30 million years,
the Indian subcontinent
has been pushing northwards into Eurasia.
On the border between India and Tibet
the rocks have been raised
eight kilometres above sea level,
creating the world's highest mountain range,
the Himalayas.
But to the east, the rocks
have buckled into a series of steep north-south ridges, cutting down through the heart of Yunnan,
the parallel mountains of the Hengduan Shan.
These natural barriers
serve to isolate Yunnan's plants and animals
in each adjacent valley. While the huge temperature range between the snowy peaks and the warmer slopes below
provides a vast array of conditions for life to thrive. Through spring, the Hengduan slopes
stage one of China's greatest natural spectacles.
The forests here
are among the most diverse botanical areas in the world. Over 18,000 plant species grow here,
of which 3,000 are found nowhere else.
Until little more than a century ago,
this place was unknown outside China.
But then news reached the West
of a mysterious, hidden world of the orient.
Hidden among the mountains, a lost Shangri-la paradise. Western high society, in the gripe of a gardening craze,
was eager for exotic species from faraway places.
This gave rise to a new breed of celebrity adventurers, intrepid botanist-explorers
known as "the Plant Hunters".
Yunnan became their Holy Grail.
The most famous was Joseph Rock, a real-life Indiana Jones. Remarkable film footage
captured his entourage on a series of expeditions,
as they pushed into the deepest corners of Yunnan.
In glorious colour he recorded the plant life he found
on special photographic glass plates.
Sending thousands of specimens back to the West,
the Plant Hunters changed the gardens of the world forever. Rock's success was born of a massive effort.
For, to find his Shangri-la,
not only had he to traverse endless mountain ranges,
but some of the deepest gorges in the world.
The Nujiang is called The Angry River.
This 300-kilometre stretch of raging rapids
is as much a barrier to life as are the mountains above.
But the plant hunters weren't the first people to travel here. Along the Nujiang, less than 30 rope crossings
allow locals' passage across the torrents.
Tiny hamlets cling to the slopes.
This morning, it's market day,
drawing people from up and down the valley.
Hanging from simple rope slings,
people have been using the crossings
for many hundreds of years.
In such narrow, precipitous gorges
it's by far the easiest way to get around.
Once across, the steep sides mean it's still a hike.
Many trek for hours by foot before they get to the market. The immense valley is home to over a dozen ethnic groups.
Some, like the Nu people, are found only here.
The markets bring the mountain tribes together.
To continue his expeditions,
Rock had to get his entire entourage
across the giant Yunnan rivers.
He commissioned especially thick ropes
made from forest rattan
and filmed the entire event.
With yak butter to smooth the ride,
40 men and 15 mules made the journey.
Not all made it across.
On the far side of the great Nujiang gorge,
the Plant Hunters made a remarkable discovery.
Far from the tropics,
they seemed to be entering a steamy,
vibrant tropical jungle,
the forest of Gaoligongshan.
The flora here is unlike anywhere else in the world. Next to subtropical species,
alpine plants grow in giant form.
Crowning the canopy, rhododendrons,
up to 30 metres high.
In April and May, their flowers turn the forests ruby red, attracting bird species found only here.
Constant moisture in the air means that
the branches are laden with flowering epiphytes, fiercely guarded by tiny sunbirds, unique to these valleys. Nectar feeders,
these are the humming birds of the Old World tropics. The forests of Gaoligongshan
are home to some of China's rarest wildlife.
This is a female Temminck's Tragopan.
She has a colourful male admirer.
He's hoping to woo her
with his peculiar peekaboo display
but she's not about to be rushed.
His colourful skin wattle
reflects more light than feathers do.
To her, this is like a neon sign.
Seeing his chance,
the male makes his move.
Constant moisture in the Gaoligongshan forests
means that throughout the year
there are always fruits on the trees.
Such abundance of food encourages
a high diversity of fruit eaters
more commonly found in the tropics.
The black giant squirrel
is found only in undisturbed rainforest. At close to a metre in length,
it's one of the world's largest squirrels.
The mystery is that
these forests are growing well outside the tropics.
By rights, none of this jungle, or its animals, should be here. These are bear macaques.
They're found only in tropical and sub-tropical jungle.
With a tiny home range of just a few square kilometres,
they depend on the abundant fruit
that only true rainforests can provide all year round.
To the European plant hunters,
these northern rainforests must have seemed
a fantastic and mysterious lost world.
Yet, when they came here, they would have found beautifully constructed ancient stone pathways
on which the forest could be explored.
Winding westwards into the hills,
these were once some of the most important highways in Asia, the southwestern tea and silk road.
Built thousands of years ago,
the southwestern tea and silk road gave access to the world beyond China's borders,
carrying tradesmen and travelers from as far away as Rome. Wars were fought over access to this tiny path,
the only sure route in or out of China,
that was guaranteed to be clear of snow all year round.
So, what causes
Gaoligongshan's strange and remarkable climate?
In late May, gusts of wind arrive,
bringing with them the key to Gaoligongshan's mystery.
The winds are hot and saturated with water.
They come all the way from the Indian Ocean.
Channelled by Yunnan's unique geography,
they bring with them the moisture of the tropical monsoon. The giant river valleys, created millions of years ago,
act like immense funnels.
The gorges are so deep and narrow, that the moist warm air
is driven right up into the north of Yunnan.
The result is rain, in torrents!
Four months of daily rainstorms sustain luxuriant vegetation. The arrival of the monsoon
awakens one of the forest's most extraordinary
moisture-loving inhabitants.
The crocodile newt is one of the most unusual
of the many amphibian species found here.
As the rains arrive, they emerge to mate.
The newts are said to leave an odour trail
that potential mates can follow.
The crocodile newt gets its name
from the bumps along its back.
These are its defence.
If grabbed by a potential predator,
the tips of its ribs
squeeze a deadly poison from the bumps.
The deluge wakes another forest inhabitant.
This one is particularly astounding in its vigour! It can grow up to a metre a day,
fast overtaking the other plants around it.
The taller it grows, the faster its growth rate,
so that in a matter of days
it towers above the undergrowth,
and continues reaching for the sky.
Not bad for what is essentially a grass.
It's bamboo.
Given the chance,
bamboo will create immense forests, dominating entire areas.
Bamboo forests occur across southwest China,
all the way to Shanghai.
But probably the highest diversity
of bamboos in the world
is found on the hills and valleys of Yunnan. Though incredibly strong,
bamboos have hollow stems,
a perfect shelter
for any creatures which can find a way in.
This entrance hole was made by a beetle
but it's being used by a ery different animal.
A bamboo bat.
The size of a bumblebee,
it's one of the tiniest mammals in the world.
The entire colony, up to 25 bats,
fits into a single section
of bamboo stem, smaller than a tea cup.
It's quite a squeeze!
Half the colony are babies.
Though barely a week old,
they are already almost as big as their moms. Feeding such a fast-growing brood is hard work. The mums leave to hunt just after dusk each night. Back in the roost,
the young are left on their own.
Special pads on their wings help them
to grip on the bamboo walls - most of the time. The young bats use the extra space
to prepare for a life on the wing
by preening and stretching.
Packed in like sardines, they would make an easy target for a snake.
But the snake has no chance of getting in.
The entrance is thinner than the width of a pencil.
When the mothers return,
they can push through the narrow entrance
only because of their unusually flattened skulls.
But it's still a squeeze.
Bamboos are exploited in a very different way
by another forest dweller.
Fresh bamboo shoots are an important forest crop.
Ai Lao Xiang is of the Hani tribe,
from the mountain village of Mengsong.
Roasted, the tender shoots he gathers will make a tasty dish. The Hani have many uses for the different bamboos
they grow and find in the forest around.
Though flexible enough to be woven,
bamboo has a higher tensile strength than steel.
Succulent when young,
in maturity it's tough and durable,
ideal for making a table
and strong enough for a pipe to last a lifetime.
The people of southwest China
have found an extraordinary number of ways
to exploit this most versatile of plants.
Part of bamboo's phenomenal success
is that it's so tough that few animals can tackle it.
Yet, bamboo does come under attack.
A bamboo rat.
Feeding almost exclusively on bamboo,
they live their entire lives in tunnels beneath the forest.
The thinner species of bamboo
are easy to attack and pull below.
She has a fantastic sense of smell
and can sniff out the fresh growth through the soil. Bamboo spreads along underground stems.
By following these, new shoots are found.
Once a shoot is detected,
she snips it free and drags it down into her burrow.
This female has a family.
At just a few weeks old,
the youngsters can already tackle the hardest bamboo stems and are eager to try.
Bamboo's tough reputation is such,
that another bamboo specialist was known by the Chinese as, "The Iron Eating Animal".
The giant panda is famous for its exclusive diet.
Giant pandas are thought to have originated
in southwest China, millions of years ago,
but they are no longer found in Yunnan.
Recently, their specialized diet
has had dire consequences.
Bamboo has a bizarre life cycle,
flowering infrequently,
sometimes only once every hundred years or so.
But when flowering does occur,
it's on a massive scale,
and it's followed by the death of all of the plants. Sometimes an entire bamboo forest may die.
In undisturbed habitat,
pandas simply move to another area
where a different bamboo species grows.
But as human activity has fragmented their forest home, pandas find it increasingly hard to find large enough areas in which to survive.
Wild pandas are now found
only in the forests of Central China, far to the east.
But in the hidden pockets of lowland jungle
in Yunnan's tropical south,
live one of China's best-kept wildlife secrets.
The wild Asian elephant.
Elephants once roamed across China
as far north as Beijing.
But it's only in the hidden valleys of Yunnan
that they have survived.
Elephants are the architects of the forest.
Bamboos and grasses are their favourite food
but saplings, tree leaves and twisted lianas are all taken, with little care.
As they move through the forest,
the elephants open up clearings,
bringing light to the forest floor.
This has a major impact on their home.
The richest forests are now known to be those
which from time to time experience change.
The Jinuo people are incredibly
knowledgeable about their forests
and claim to have uses for most of
the plants that they find there.
They have names for them all,
those good for eating and some which
even have strong medicinal qualities.
By working here,
the Jinou play a similar role to the elephants,
opening up the forest, bringing space, light and diversity. Green, fast growing species are encouraged.
Insects are in high abundance here,
together with the animals that feed on them. Knowledge of the forest enables the Jinou to find not just plants,
but other tasty forest food too.
Forest crabs are common here,
feeding on the abundant leaf litter.
This will be a tasty addition to the evening meal. Flowing through Yunnan's southern valleys,
the once angry rivers are now swollen,
their waters slow and warm.
These fertile lowland valleys are the home of the Dai. The "People of the Water" live along streams
which originate in the surrounding hills.
Each family keeps a kitchen garden
modelled on the multi-layered structure
of the surrounding forests,
which the Dai hold sacred.
The gardens are made more productive
by inter-planting different crops.
Tall, sun-loving species give shelter
to plants which thrive in the shade.
As companions, the plants grow better.
Yunnan's forests are home
to more than a dozen wild banana species
and banana crops grow well in most Dai gardens.
The huge banana flowers are rich in nectar
for only two hours a day,
but it's enough to attract a range of forest insects, including hornets.
With their razor sharp mandibles,
they find it easy to rob the flowers of their nectar.
But hornets are predators too.
They hunt other insects and carry them back to their nest. An ideal target,
but this grasshopper is no easy meal.
There may be a price to pay.
The Dai men, Po and Xue Ming,
Take advantage of a hunter's instincts.
A hornet sting is agony.
But for now it's distracted,
intent on cutting away a piece of grasshopper
small enough to carry back home.
Success!
The white feather hardly slows the hornet,
and, more importantly,
it can be seen.
Now the hunter is the hunted.
So long as Po and Xue Ming can keep up!
Back at the nest,
the other hornets immediately begin to cut the feather free. But it's too late.
The nest's location has been betrayed.
The relationship between the forest animals
and the people who live here
was never one of harmony.
Yet the fact that the Dai and other ethnic groups considered these forests to be sacred,
has ensured their survival
and now many have been given extra protection
as nature reserves.
Ingenuity and hard work pays off at last.
The fattened larvae are considered a delicacy by the Dai. Although these forests
have experienced a great deal of change,
they are still host
to some ancient and incredible relationships.
Almost 60 centimetres high,
this is the immense flower of the Elephant yam.
Locals call it the "Witch of the Forest".
As the stars rise,
the witch begins to cast her spell.
The forest temperature drops,
but the flower starts to heat up.
A heat sensitive camera reveals
the flower's temperature rising
by an incredible ten degrees Celsius.
At the same time, a noxious stench of rotting flesh
fills the forest air.
As the flower's heat increases,
a cloud of odour rises up.
The foul perfume carries far and wide.
It doesn't go unnoticed.
Carrion beetles arrive on the scene.
The beetles come in search of
a feast of warm decaying flesh,
but they've been tricked.
Slippery sides ensure they tumble straight
into the centre of the monster flower.
There's not enough room to spread their wings
and the waxy walls ensure that there's no escape.
But there's nothing sinister in the flower's agenda.
The beetles will be its unwitting helpers.
Dawn arrives,
but the flower remains unchanged,
holding its captives through the day.
As the second night falls,
the witch stirs again.
In a matter of minutes,
the flower's precious golden pollen
squeezes from the stamens and begins to fall,
showering onto the captive beetles below.
Now, at last, the prisoners are free to go.
The flower's wall changes texture,
becoming rough to provide the ideal escape ladder.
Loaded with their pollen parcels,
they can now climb to freedom,
just as other forest witches are beginning to open.
Seduced by the irresistible perfume,
the beetles are sure to pay a visit,
so ensuring pollination,
and another generation of incredibly big, smelly flowers.
As dawn arrives,
forest birds claim their territories in the canopy.
But there's one call which stands out among the rest - virtuoso of the forest symphony.
It's a gibbon.
Living on a remote mountain range in south central Yunnan is one of the few remaining wild gibbon populations in China. The black-crested gibbons of Wuliangshan.
They are confined to these forest mountains,
so remote and steep that few hunters ever come here.
The Wuliangshan gibbons are unusual
for their social structure.
Most gibbons live in small family groups
consisting of a mating pair and their offspring.
But these gibbons exist in troops.
One male can have two or sometimes three females
and all of these can have young.
Often even the juveniles stay in the community.
Rarely glimpsed,
this baby may be only a day old.
If it survives infancy,
then it has a promising future in these few valleys
with its close-knit family.
Gibbon song once inspired the ancient poets of China,
their glorious calls echoing far across the hills.
But now, new, strangely quiet forests have come to Yunnan. These trees are here
to produce an important and valuable crop.
When the tree bark is scored, it yields copious sticky sap,
so bitter and tacky that nothing can feed on it.
It's the tree's natural defence against attack.
It's collected daily, bowl by bowl.
It will be boiled and processed
Into one of the most important materials
to a fast developing nation - rubber.
The expansion of the rubber forests
began in the '50s when China,
under a world rubber embargo,
had to become self-sufficient in this vital product. Beijing turned to the only place where rubber could grow, the tropical south of Yunnan.
With efficiency and speed,
some of the world's richest forests were torn up
and burned.
Replaced with mile upon mile of rubber plantation.
But there was a problem for the rubber growers.
While Yunnan's unique natural forests can survive
on the valley slopes which stretch to the north...
just one severe frost will kill off
these delicate rubber trees.
So Y unnan's terrain puts a limit
On how far the plantations can spread,
halting at least their northwards advance.
The jungles of Y unnan
are increasingly under pressure.
New roads crisscross the tiny remnant forests,
the infrastructure needed for trade, industry and, increasingly, tourism.
It's a meeting of two very different worlds.
That elephants still exist in China is remarkable considering the immense pressures
in the world's most highly populated country.
The 250 or so wild elephants which still live here
are now strictly protected.
And each year young are born to the small herds.
If elephants were to survive anywhere in China,
it could only have been here, in Yunnan.
The same mountains
which guide the monsoon rains north
and which made Joseph Rock's journeys so treacherous, also guarded Yunnan's forests
and its wildlife.
For the moment,
the mountains are still carpeted in a rich green, deceptive in its simplicity.
Below the canopy
lies perhaps China's richest natural treasure.
Delicate and unique,
a complex world of intricate relationships
between animals, plants and people,
beneath the clouds.
The Tibetan plateau is a quarter of China.
Much of it is extremely remote and inhospitable.
Its southern border
runs through the world's highest mountain range,
the formidable Himalayas.
Its central part is a windswept and freezing wilderness
the size of Western Europe.
But this challenging place is home to incredible wildlife. There are more large creatures here
than anywhere else in China.
Tibet has been a province of China for more than 50 years, yet it has a unique character,
shaped by over 1,000 years of Tibetan Buddhism.
This obscure and archaic-looking religion
has produced one of the most enlightened cultures on Earth. Here,people have a long tradition of co-existing peacefully with the creatures and landscape around them,
a relationship which has helped to protect
their fragile environment.
In this programme we will discover
why this harsh land with its ancient culture
is vitally important for much of our planet.
It's the beginning of winter,
high up on the Tibetan plateau.
The temperature will soon drop to minus 40 Celsius.
Out here,life is reduced to a single imperative - survival. For the argali, the world's largest sheep,
it means searching for a few tufts of grass.
Descending from the hilltops to lower altitudes,
the argali band together for safety.
Hopefully,down here, they'll be able to find enough food
to last them through the rest of the winter.
Although this winter landscape looks barren and forbidding, Tibet's remote grasslands
support a surprising variety of creatures.
Though at this time of year, they can be hard to track down. By comparison,Tibet's capital, Lhasa,is a hive of activity. Lhasa is a focus for large numbers of pilgrims
who congregate at the city's temples each day.
Tibet is home to over 2.5 million people,
most of whom are deeply religious.
Though Tibetan Buddhist worship centres
on elaborate temples, statues and images,
its beliefs are intimately linked
with the wild landscapes of Tibet.
The starting point for that relationship is the mountain range that runs along Tibet's southern border.
Over 3,000 kilometres long,
the Himalayas are China's real Great Wall.
With hundreds of peaks over 7,000 metres
and 13 peaks higher than 8,000 metres,
they are the highest mountains on Earth.
The Tibetan region contains over 35,000 glaciers
that cover over 100,000 square kilometres.
They comprise the largest area of ice
outside the polar regions,
and nearly a sixth of the world's total.
These glaciers are the source
of most of the water in the region.
And the Tibetan plateau is studded with glacial lakes.
At over 4,500 metres up,
Lake Manasarovar in the far west of Tibet,
is the highest freshwater lake in the world.
In late spring,
the chilly lake waters are a magnet for breeding birds. The crested grebe woos his mate
with offerings of weed for her nest.
Finally the honeymoon suite is ready for action.
The grebes are joined
by the highest flying birds in the world.
Having spent the winter south of the Himalayas,
bar-headed geese
make the hazardous mountain crossing each spring
to breed on the plateau's lakes.
The geese nest together for safety.
But so many chicks hatching at the same time means that it can be tricky finding your parents.
Fortunately, once down at the water's edge,
there's enough food for all of them.
Fed by the mountain glaciers,
the Tibetan plateau even has its own inland sea.
This is Qinghai Lake, China's largest.
Millions of years of evaporation
have concentrated the minerals in the lake,
turning the water salty.
Rich in fish, its waters attract thousands of cormorants. But it's not just wildlife that values Tibet's lakes and seas. Their life-giving waters are also important to people. Tibetan religion is a unique mix of Buddhism
and much older Shamanic beliefs
that were once widespread throughout the region.
This hybrid religion forms the basis
of an extraordinary relationship with nature.
In Shamanic belief,
the land is imbued with magical properties
which aid communication with the spirit world. Here animal skulls are decorated,
and rocks are carved with sacred mantras,
groups of syllables that are considered to have spiritual power. The reciting of the mantras
is believed to create a magical sound
that reverberates through the universe.
The landscape is decorated with multi-coloured flags
which represent the five elements -
fire, wood, earth, water & iron.
The flags are printed with prayers
to purify the air and pacify the gods,
and the wind blows the prayers to heaven.
The poles on which the prayer flags are mounted
are regularly replenished with fresh flags.
The old flags are treasured.
Those nearest the top of the pole are the most auspicious,
so competition for these can get fierce!
The golden dome,
which is mounted right at the top of the prayer pole,
is the most sacred object of all.
Or it will be, once it's retrieved.
The old Shamanic beliefs of Tibet
ascribed magical powers to the landscape...
but there's a far more tangible source of power here
which owes nothing at all to magic.
Strewn across the plateau are boiling thermal springs,
the evidence of mighty natural forces
which have been at work over millions of years.
Deep below the surface,
the vast continental plates of Asia and India
are crashing into each other.
The turmoil below erupts in clouds of sulphurous steam.
It seems unlikely
that scalding mineral springs should support life.
But one unlikely creature
thrives here precisely because of them.
The hot spring snake is unique to Tibet and is believed
to have survived the inhospitable conditions up on the plateau principally thanks to this natural central heating.
These cold-blooded snakes hang out in streams and rivers which are fed by the hot springs,
where they enjoy a surprisingly productive lifestyle. Slipping into the warm water, they wait patiently,
bobbing their heads on the lookout for fish.
Thanks to its unlikely relationship with the volcanic forces which built the Himalayas,
the hot spring snake is able to survive
at altitudes up to 4,500 metres,
making it the highest-living snake in the world.
The slow-motion crash between Asia and India
has been going on for 30 million years.
The Himalayas are the crumple-zone
created by these two colliding landmasses,
a bewildering maze of mountains and valleys,
home to elusive wild creatures.
In this rugged and unforgiving terrain,
Iittered with fractured rock and ice cold rivers,
the slightest miscalculation may have fatal consequences. The snow leopard is the world's highest-living big cat. But there's another,
smaller predator that ranges even higher,
almost to the roof of the world.
At a mind-numbing 8,848 metres high,
Everest is one of the most hostile places for life on Earth. Hundreds of people have died trying to conquer it.
But when climbers first reached the ice fields
three quarters of the way up the mountain,
something had already beaten them to it.
This jumping spider
is the highest permanent resident on the planet.
Totally at home amongst the glaciers of Everest,
it scours the slopes
for wind-borne prey such as springtails.
Chinese call this fierce little hunter the "fly tiger". Jumping spiders are found all over the world.
Their eight eyes include an oversized central pair, which act like powerful binoculars
to spot potential victims.
They use hydraulic pressure
to work their legs like pistons,
catapulting up to 30 times their own body length.
The ideal way to get around in rocky terrain.
But like all mountaineers,
they always secure a safety line first.
A springtail grazes on detritus,
unaware that it's being stalked
by such an acrobatic predator.
The Tibetans call Everest "Qomolangma",
meaning "mother of the world".
It's a mark of their affection for the mountain,
however brutal it may appear.
Venture further from the mountains
and out onto the open plateau,
and life doesn't appear to get any easier.
High winds scour the landscape
and temperatures can drop from baking to freezing
in moments.
This is the Chang Tang or Northern Grassland. It's so remote that it's been called the Third Pole.
It's about 5,000 metres above sea level,
way above the point at which altitude sickness
starts to affect humans.
At this height, most people are gasping for breath.
But lack of oxygen hasn't cramped this creature's style. Chiru, or Tibetan antelope, have arrived for the winter rut.
In the energy-sapping thin air,
the males must try to control groups of females
by constantly rounding them up and corralling them.
But the chiru have an advantage.
Their red blood cell count is twice as high as ours,
sufficient to supply their muscles with oxygen
even at this extreme altitude.
Nevertheless, it's hard work keeping his harem in check,
and the male's life is about to get even harder.
Another male is gearing up to steal his females.
With their rapier-like horns,
the males won't risk fighting unless they really have to.
But if neither backs down, conflict is inevitable.
Some of these fights end in death.
While the males fence, the females look on.
Injured and weakened by the battle,
the loser will be an easy target
for the predators and scavengers that patrol the wilderness. Out here there's little room for mistakes.
With a clear view of the endless plateau below,
vultures are quick to spot any opportunity.
A dead yak has drawn a crowd.
Vultures aren't famous for their table manners.
The vultures do well here,
as the vast Tibetan wilderness is home to many large creatures. Living in herds of up to 200
in the remoter corners of the Tibetan plateau,
wild yaks travel large distances, grazing on the alpine tundra. Strong and secure over mountain passes and rivers,
the yak is in its element at altitude.
So much so that it gets sick if it goes below 3,000 metres. Standing two metres tall at the shoulder
and weighing more than 800 kilos,
the wild yak is both formidable and aggressive.
But without this fearsome creature
it's unlikely that humans would have survived up here.
Once domesticated, the yak is an amazing animal,
providing the Tibetans with transport,
food, wool for clothes and tents, and manure for fuel.
It's held in such high regard that
its fur is even used to decorate the sacred prayer flag poles, and yak butter is used as an offering to the gods.
The yak has even led the Tibetans to buried treasure.
In summer, people can be seen scouring the grassland, bent over in deep concentration.
This is the world's weirdest harvest.
Tibetans first investigated this strange root-like organism, known locally as "yartsa gunbu",
when their yaks appeared to have more energy
after grazing on it.
Rumours of its amazing properties gradually spread
and today the yartsa gunbu
is a passport into a shady, underground world.
It's possible to dig up 40 of them in a day,
the proceeds from which
may provide half the collector's annual income.
Yartsa gunbu has been used as a traditional remedy
for thousands of years,
though only by the very wealthy.
It has been bartered for tea and silk,
and is worth more than four times its weight in silver.
So lucrative is this trade,
that sites and information are jealously guarded.
At the nearby market, the yartsa gunbu are cleaned,
and their true nature becomes clear.
The yartsa gunbu translates as
"summer grass, winter worm".
The winter worm is a caterpillar.
It eats roots of grasses
in preparation for its transformation into a moth.
But some winter worms never make it as moths. Instead, a strange growth erupts from their body, appearing above ground in summer.
This is the "summer grass" -
a fungus called Cordyceps,
whose spores have infected the caterpillar,
using its body as their host.
Modern scientific tests have shown
that substances contained in Cordyceps
lower blood pressure and make it easier to breathe.
So in recent years, harvesting this natural treasure
has grown into a huge and profitable business.
Yartsa gunbu sells for big money
in the top department stores of Lhasa,
and there is a growing market outside of Tibet. Although Tibet is modernising fast,
it retains a deeply spiritual culture.
Even today, Tibetan valleys resound
to distinctive and extraordinary calls to prayer.
The Tibetan horn may be
the world's most unwieldy instrument, but its sound is unique.
Every morning, the nuns assemble for practice.
The air is chilly, but they soon warm up.
Monks and nuns comprise a substantial portion of society, Iargely self-contained and isolated.
Deep within the monastery
is the spiritual engine that drives much of Tibetan culture. Buddhists believe in an endless cycle of rebirth
in which the actions of this life will impact on the next.
The goal of Buddhism is to escape
from this earthly cycle of pain and suffering
by achieving a state of freedom called enlightenment.
The enlightened guides, or spiritual teachers, are called lamas. The possibility of escaping the cycle of life and death
and the promise of enlightenment encourages people
to perform activities that benefit all beings.
This belief assigns as much importance
to the environment and its creatures as it does to humans, since every living creature is believed to have a soul.
In the remote lands of Tibet, for over 1,000 years
this concept has been translated
into practical benefits for wildlife,
and it starts literally on their doorstep.
Buddhist monasteries have sacred sites,
areas where taboos are placed
on the hunting and killing of animals.
Some creatures have become so tame
that the nuns are able to hand-feed them,
Iike these Tibetan-eared pheasants.
Thanks to hand-outs from the nuns,
these rare birds can survive the worst of the winter.
In this extreme place, people with few resources
are prepared to share them with their needy fellow-creatures. The Tibetan example is a model for conservation.
This respect for wildlife extends beyond the monasteries
and into the wider community.
One of Tibet's most sacred creatures is the black-necked crane. In summer they live and breed out on the plateau,
but in winter they congregate on farmland.
70% of the world's population can be found here.
The species was only recently identified by scientists,
but it has been known to Tibetans for hundreds of years.
In the 17th century, Tibet's supreme lama wrote,
"Crane, lend me your wings,
I go no farther than Lithang county.
"And thence, return again. "
Tibetans believed
he was predicting the site of his own reincarnation
and in due course his successor was found,
sure enough, living in Lithang county.
Even today,black-necked cranes
are treated with reverence
and are welcomed by farmers
as they land in the fields around the villages.
Here they perform their elaborate sky pointing rituals. After the dignified business of parading,
they begin to forage for leftover barley...
helped by the pigs which break up the soil.
The farmers are happy to have these sacred birds
on their fields.
Within the village, religion is an integral part of life. Each prayer wheel is inscribed with mantras.
Spinning them has much the same effect
as reciting the prayers.
Perhaps the Buddha would have enjoyed the thought that his teachings could provide so much fun!
Buddhist respect for nature
may find expression in practical ways too.
This bird has a broken wing
and has been nursed back to health by the villagers. Such kind acts are common where people believe that helping other beings, animals or people,
in this life may bring rewards in the next.
The culture of veneration and protection extends
right across Tibet,
helping to preserve a unique yet fragile ecosystem.
Out on the plateau there's a small creature that's
at the root of much of the grasslands' delicate ecology. Despite summer snowstorms,
the pika, a relative of rabbits and hares,
is perpetually eating and gathering grass,
and digging burrows for its family.
The pika's constant excavations aerate the soil,
which helps the plants to grow.
In the short summer,the landscape is carpeted
with hardy grasses and decorated with endemic flowers. In such a frugal environment,
the pika's farming helps to kick-start the food chain.
But the pika itself is a very tasty morsel.
Its presence has enabled
an uneasy relationship to develop
between two of the plateau's most opportunistic predators...
..the fox and the bear.
The Tibetan brown bear, a close relative of the grizzly, tries to dig the pikas out of their burrows.
Even hard-frozen soil presents little obstacle
to a determined bear. Meanwile, the wily Tibetan fox trails the bear
hoping to profit on the confusion.
True to form, the crafty fox claims the prize.
A combination of inaccessibility,
and ancient traditions which forbid hunting,
means that in some parts of the plateau,
wild animals have remained relatively undisturbed, even today. But in those areas which are within reach of motor vehicles, these historical safeguards have been undermined.
This change is illustrated in the fortunes of the chiru.
A century ago, millions migrated across the plateau. Unfortunately for the chiru, its fur, known as "shahtoosh",
or "king of wools", is highly prized.
In recent decades, poachers have been able to venture
deep into the wilderness, killing thousands of chiru. However, the situation is improving.
Anti-poaching laws are now actively enforced
so every summer,
female chiru can head to the birthing grounds in relative safety. Out on the plateau, new-born chiru are vulnerable to predators, so the mothers must try to hide and protect them.
The most recent problem faced by the chiru
is the new Tibet-Qinghai railway,
which cuts right through their traditional migration routes. Running nearly 2,000 kilometres
through some of the highest terrain on Earth,
the railway is an astonishing technical feat.
It's too early to see its effect on the wildlife,
but the engineers have made efforts to incorporate underpasses where wildlife can cross the line in safety.
As the modern world increasingly impacts on Tibet,
its traditions could be in danger of being eroded.
But thanks to the sheer scale of this remote region,
there are still many wild places
that have so far remained largely intact.
The least explored area of all is found in Tibet's far south east. Here the Yarlung River, Tibet's longest,
has carved through the Himalayas,
allowing monsoon clouds from India to pass through.
This is Tibet's most secret corner.
According to legend, the Yarlung gorge
was rendered magically invisible in the eighth century
and can only be seen by those who have attained
sufficient spiritual knowledge and wisdom.
At two days' walk from the nearest road,
this hidden region wasn't explored by outsiders until the 1990s. Thanks to the annual monsoon,
the whole landscape is covered in lush forest.
The scale of the gorge is breathtaking.
As the Yarlung River cuts through the mountains,
it's created the world's deepest gorge,
three times deeper than America's Grand Canyon.
This vast and mysterious place provides a vital clue
to Tibet's importance for the rest of the world.
The monsoon which sustains this lush and fertile valley owes its very existence to the Tibetan plateau.
Like a giant hotplate,
the plateau heats up in the spring and summer.
The change in air pressure draws in warm moist air from the Indian Ocean in the south.
Thanks to this, over a billion people from India to Burma benefit from the monsoon rain
that this wind brings with it.
Tibet is the engine that drives the fertility
of a whole subcontinent.
But Tibet has an even greater role
in the ecology of the region.
Clues to this function are found in a legend
that predates even the ancient Tibetan culture
and which still draws pilgrims from all over the world. Several world religions believe in a mythical mountain that's equivalent to the Garden of Eden.
Its peak has four faces,
aligned to the points of the compass,
and from its summit four rivers are said to flow
to the four quarters of the world.
Thanks to its life-giving waters,
this mountain is known as the "axis of the world. "
In one of the remotest areas of Tibet,
there's a place where this legend takes physical form. That place is Mount Kailash.
By an uncanny coincidence,
Mount Kailash perfectly matches the legend
of the mythical axis of the world.
Its four faces are roughly aligned to the compass,
and four major rivers flow from its foothills.
These are some of the most significant rivers in Asia. The Yarlung, which becomes India's Brahmaputra,
the Indus and Sutlej, which flow to Pakistan,
and the Karnali, a major feeder for the Ganges.
Thanks to its connection with the mythical mountain, Kailash is so sacred that it has never been climbed.
It's Tibet's most important pilgrimage site.
For Tibetans,
pilgrimage is a journey from ignorance to enlightenment.
A pilgrimage around the sacred mountain is believed
to wipe out the sins of a lifetime,
increasing the chance of a better rebirth. Most pilgrims time their visit for the most important festival
in the Tibetan calendar.
For over 1,000 years they have gathered at the foot of Kailash for the Saga Dawa festival
to celebrate Buddha's enlightenment.
The festival climaxes
with the raising of the newly dressed altar, a 25-metre flagpole. The full entourage of Tibetan monks
make the most of the occasion,
with music, prayers, and blessings.
Hundreds of fresh prayer flags are prepared
and added to the pole.
The head lama's sacred scarf adds the final touch
to the proceedings.
But the significance of Mount Kailash
isn't confined to Buddhists alone.
Other faiths venture to this remote place,
many from far beyond the Himalayas.
Threatening to upstage the Buddhists, the Hindus arrive, adding their own mix of colour and music.
When suitable respect has been paid,
it's time for the newly dressed prayer pole to be raised.
The pole must end up straight
or it will be a bad omen for Tibet.
At last the pole stands true
and the new prayers can be blown to the heavens.
Around this point, the power of the Tibetan landscape
and the beliefs of many cultures converge.
More prayers, written on pieces of paper called "wind horses", are thrown into the air and flutter
upwards towards the peak of Kailash,
where the gods of the different faiths are believed to reside. Here at the axis of the world, is a rare vision of harmony.
For a few, there is one final but essential task to perform. Buddhists believe in the concept of rebirth, and at Kailash
the journey from one life to the next
is marked with an ancient but outlandish ritual.
Tibetans believe there's no need
to keep or bury the bodies of their dead,
since a departed life will already have
kindled a new one elsewhere.
The word for burial in Tibetan
means "giving offerings to the birds",
an act of generosity
in line with the concept of compassion for all beings.
By doing good deeds, Buddhists believe that
they can contribute to the process of enlightenment.
So a sky burial at Kailash contributes to a brighter future. There may be legends of mythical mountains and rivers
that form the "axis of the world".
But the Tibetan plateau itself,
with its mountains,glaciers,and rivers,
and as the engine that drives the monsoon,
lays fair claim to being the real axis of the world.
Apart from feeding the rivers of India and Pakistan, Tibet's glaciers are the source of even more great rivers. Vietnam's Mekong, Burma's Salween
and the Yangtze and the Yellow,
both of which flow into China.
Each year, enough water flows from the Tibetan plateau to fill the entire Yellow River,
the mother river of Chinese civilisation.
Today in China alone,
300 million people depend on water
from the Tibetan plateau.
With its profound effect
on Asia's weather and water systems,
the Tibetan plateau helps to sustain
almost half the world's population.
For the moment, at least.
Close to the summit of Mount Everest,
a forest of ice once covered much of the area.
But now, thanks to climate change,
much of it has gone.
Within the next 30 years
it's predicted that 80% of the Tibetan glaciers
could disappear.
In many ways,
Tibet's fragile environment is the barometer of our world. What happens to it today,
in time, will affect us all.
The Great Wall of China was built by the Han Chinese
to keep out the nomadic tribes from the north.
They called these people barbarians,
and their lands were considered barren and uninhabitable. Northern China is indeed a harsh place
of terrible winters, ferocious summers, parched deserts. But it is far from lifeless.
With colourful places, surprising creatures,
amazing people and strange landscapes.
The further we travel, the more extreme it becomes.
So how do people and wildlife cope
with the hardships and challenges
of life beyond the Wall? The northern limits of Ancient China
were defined by the Great Wall
which meanders for nearly 5,000 kilometres from east to west. The settled Han people of the Chinese heartland
were invaded many times by warlike tribes from the north. The Great Wall was built
to protect the Han Chinese from invasion.
To meet those fearsome northerners
and the wild creatures who share their world,
we must leave the shelter of the Wall
and travel into the unknown.
Northeast China was known historically as Manchuria.
Its upper reaches are on the same latitude as Paris
but in winter it is one of the coldest,
most hostile places on the planet.
Bitter winds from Siberia regularly bring temperatures
of 40 degrees below zero.
Dense forests of evergreen trees cover these lands.
And the rugged terrain is made even more difficult
by impenetrable ravines.
We start our journey on a frozen river
snaking between China's northeasternmost corner and Siberia. The Chinese call it the Black Dragon River.
The people who live here aren't exactly fearsome warriors. They're too busy coping with the harsh winter conditions
and they respond to the challenge in some creative ways.
The Black Dragon River is home
to one of the smallest ethnic groups in China.
The Hezhe People.
It's not just bicycles that seem out of place in this icy world. Fishing boats and nets lie abandoned,
a long way from open water.
Underneath a metre of solid ice swim a huge variety of fish, including 500-pound sturgeon,
enough to feed a family of Hezhe for weeks.
But how can they catch their quarry?
First they must chisel a hole through the ice
to reach the water below.
Then they need to set their fishing net under the ice,
a real challenge.
A second hole is made, 20 metres away from the first
and a weighted string is dropped in.
Then, a long bamboo pole is used to hook the string
and pull the net into position beneath the ice.
After a few days, the nets are checked.
These days, almost nobody catches a rare giant sturgeon.
The Black Dragon River has been overfished
like so many others.
But even these smaller fish are a welcome catch.
Frozen within seconds,
the fish are guaranteed to stay fresh
for the wobbly cycle ride home.
The forests that lie south of the Black Dragon River
are bound up in snow for more than half the year.
It's deathly silent.
Most of the animals here are either hibernating
or have migrated south for the winter.
But there is an exception.
Wild boars roam the forests of the northeast.
Like the Hezhe people,
the boars find it difficult to gather food in winter.
To survive, they follow their noses,
among the keenest in the animal kingdom.
They will eat almost anything they unearth.
But one energy-rich food source is particularly valued. Walnuts.
When a lucky boar finds a walnut,
there's bound to be trouble.
But despite the squabbles,
wild boars are social animals
and gather together in groups.
Staying close together may help them
to keep warm in the extreme cold.
But there is another reason for group living.
More ears to listen out for danger.
Siberian tigers also live in these forests.
But these days, only in captivity.
There may be less than
a dozen wild Siberian tigers left in China.
Though there are many more in breeding centres.
This enclosure at Hengdaohezi
started breeding tigers in 1986
to supply bones and body parts
for the Chinese medicine market.
Trade in tiger parts was banned in China in the 1990s and the breeding centre is now just a tourist attraction. The forests of the northeast stretch to where the Chinese, Russian and Mongolian borders meet.
Here, a surprising herd of animals is on the move.
The reindeer were introduced to China
hundreds of years ago by the nomadic Ewenki people who came here from Siberia.
It's late April,
and the women are calling in their reindeer,
which are semi-wild,
and have spent all winter away in the forest.
This is a very special relationship.
Each reindeer has its own name and many were hand-reared by these women.
Finally reunited after months apart,
they will now remain together until autumn.
The Ewenki women are anxious
to check the condition of their animals
and to see which of the reindeer might be pregnant.
Eighty-one-year-old Maliya Suo
is one of only 30 Ewenki people still living the nomadic life in these cold northern lands.
Almost all her fellow Ewenki have given up the forest life to settle in concrete houses in modern cities.
The reindeer herders are now almost as rare
as wild Siberian tigers.
There's about to be a new addition to the family.
The women act as midwives to the newborn calves, helping to nurture them
through their first precious minutes of life.
But the world around them is changing fast.
This could be the last generation
this ancient partnership will endure.
This is hardly the image of the dangerous tribal people
that the Great Wall was built to keep at bay.
Along China's border with North Korea
is this region's most famous mountain, Changbaishan.
Its name means Ever-White,
and it harbours the world's highest volcanic lake.
Even in mid-May there is still ice everywhere.
But there are signs that the seasons are changing.
Warmer winds arrive from the south,
and within a few short weeks
Changbai Mountain is transformed.
Water begins to flow down the mountainside once more, replenishing the landscape.
It's June, and insects emerge to take advantage
of the abundance of flowers.
The warm weather sees the arrival of migrant birds. Stonechats that have spent the winter in the south of China return here to raise their chicks.
With so many insects around,
the stonechats may have several broods.
Heading west from Changbai Mountain,
the forests give way to rolling grasslands.
The Great Wall stretches off into the distance,
defining the southern limits of the vast Mongolian Steppe. North of the Wall are huge areas of grassland
but one place on our journey is particularly significant.
In the tall grass, a family of red foxes is raising its cubs. Today they have this meadow pretty much to themselves. But it wasn't always the case.