Original subtitles

(THEME MUSIC PLAYING)

DAVID ATTENBOROUGH: There are only fourteen peaks in the world

that rise to over 8,000 metres.

All of them are here in the Himalayas.

Lethally cold, scarred by gales and blizzards,

these mountains are among the most hostile places on Earth.

Yet, a few special animals manage to live here.

Snow leopards.

Like all creatures of the high mountains,

they have had to adapt both their body and their behaviour,

in order to survive.

Life at extreme altitude has shaped

some of the toughest animals on the planet.

(GRUNTS)

The sun-baked mountains of the Arabian Peninsula.

They may only be a fraction of the height of the Himalayas,

but they are still so dizzyingly steep

that in many places it's almost impossible to get a foothold.

Yet, Nubian ibex have made this their home.

(BIRD SQUAWKING)

The ibex choose the steepest cliffs to raise their young

in safety, beyond the reach of predators.

But living this sanctuary comes with a cost.

These nursery slopes are so steep,

there is almost no standing water up here.

So, to drink, an ibex family must descend into the valley,

three hundred metres below.

The mothers pick out the safest way down.

With soft cloven hooves that grip better than any climbing shoe,

they are the most accomplished mountaineers.

But the newborn kids are still having to find their feet.

This is their first descent.

One mistake could make it their last.

(BLEATING)

Following the adults, the kids finally reach the valley.

But once on level ground, they're vulnerable.

Red foxes lie in wait.

At the first sign of danger,

the young ibex instinctively run back to steeper ground.

(BLEATS)

But heading for this particular rocky outcrop

could be a mistake.

It's a ten-metre drop.

The fox has them trapped, or so it seems.

This is what ibex were born to do.

Scattering makes it hard for the fox to pick a target.

And it certainly can't follow them up here.

All it can do is wait for one to slip and fall.

But these youngsters are fast learners

and they're now almost as sure-footed as their parents.

The fox will have to find its meal elsewhere.

(BIRD SQUAWKING)

It's just not been a good day.

Now, at last, the young ibex can drink.

But they'll soon need to return to the safety of the sheer cliffs.

Mastering precipitous terrain is always challenging,

but there are more fundamental problems for life in the mountains.

The Alps, Europe's highest peaks.

It's winter, and food is desperately short.

The golden eagle has to spend every daylight hour

scanning the slopes for something, somewhere, to eat.

Her two-metre wingspan allows her to glide effortlessly

for over 100 kilometres in a single day.

Her extraordinary eyes enable her to spot prey

from over three kilometres away.

But she is not the only one who's looking for food.

When she spots a chance, she must move fast.

She can dive at over 300 kilometres an hour,

only a peregrine is faster.

(SQUAWKING)

During winter, even eagles rely almost entirely on carrion.

It's a dead fox, and it could sustain her for days.

Other scavengers must defer.

The hungry crows soon regain their courage.

They'll try any trick to steal a morsel.

And they are annoyingly persistent.

But this mob are the least of her worries.

A bigger eagle takes control.

But this kill is too important to give up,

so she must fight.

For the moment, she's won the carcass back.

But a kill like this will attract every eagle for miles around.

As ever, the strongest wins the lion's share.

Unable to defend the carcass any longer,

the first eagle must now continue its search.

It may be many days before she feeds again.

Only the most competitive

will survive the perils of the mountain winter.

(THUDDING)

(RUMBLING)

An avalanche, nine million tonnes of snow

travelling at 120 kilometres an hour,

capable of smashing everything in its path.

The mountains of North America

are hit by thousands of avalanches every year.

Yet, one animal spends the whole winter

slumbering within the snow on these avalanche-prone slopes.

And when spring comes, they emerge.

All across these mountains,

grizzly bears make their winter dens up to 3,000 metres high

in the deep snow of leeward slopes.

And while they were half asleep in the depths of winter,

their young were born.

Now, these cubs are taking their first steps into the outside world.

This mother is leading her three youngsters

to a place where they can find food.

(RUMBLING)

They need to descend as quickly as possible.

The debris from an avalanche is clear evidence

that this slope is still dangerously unstable.

This is not a place to dawdle.

And they have another reason to keep moving.

After five months in the den, these bears are very hungry.

Bears that have hibernated throughout these peaks

now all descend to the valleys,

where spring comes earliest.

In the Rockies, seasonal change is swift and dramatic.

In just a few days, the slopes turn from white to green.

(SNIFFING)

Meadows that only a few weeks ago were buried beneath the snow

are now full of life.

(BEE BUZZING)

But in these mountains, the good times will not last long.

So the bears must feed as fast as they can.

During the summer months,

an adult can put on 180 kilos, gorging on plants.

And if they can catch them...

(SHRIEKING)

...a marmot or two.

But, just now, the bears have something else on their minds.

It's becoming warmer,

and the bears are keen to shed their thick winter coats.

Mothers show the cubs what to do about this.

They'll soon catch on.

Some trees, it seems, are particularly suitable for rubbing.

Bears have their favourites,

and will travel long distances to visit them.

Some itches just have to be scratched.

There are now around 30 bears in this one valley.

As they rub, each leaves an individual and recognisable scent.

So the tree soon carries a list of who's around.

Which might help individuals to avoid a fight.

To best spread their scent.

They really have to put their back into it.

(GRUNTING)

But the summer is short.

Itches satisfactorily scratched,

it's time to eat.

In a couple of months,

they will have to return to their dens to hibernate.

So now they must put on as much weight as they can.

Winter in the mountains returns fast and hits hard.

(WHOOSHING)

Temperature in the Rockies will drop to -65 degrees.

So cold, that moisture in the air freezes into tiny crystals

called diamond dust.

This bobcat

is one of the few hunters to remain active in winter.

Most of his prey is now hidden beneath the snow

that covers his entire territory.

He hunts by listening for the faintest sound of movement.

And to prevent crunching footsteps from revealing his presence,

he uses boulders as stepping stones.

A mouse.

But one is not enough.

The deeper the snow, the harder it is to detect prey,

and the rewards for the effort can be disappointing.

To say the least.

By mid-winter, the snow is so deep,

the bobcats are forced to leave their territories

to try and find easier hunting.

And this bobcat may be in luck,

for this particular valley is blessed.

A river here never freezes.

It's fed by a volcanic hot spring that heats these waters

to 50 degrees warmer than the surrounding air.

Hungry animals of all kinds come here to feed.

Throughout the winter, the river is full of food

for those who know how to catch it.

Here, even the coyotes have become fishermen.

But hunting is hard for a cat that's not used in getting its feet wet.

So he must choose his target with care.

Goldeneye ducks.

But can he get close enough to pounce?

(DUCKS QUACKING)

Perhaps he'll have more luck on the other side.

Here, steam from the river warms the surrounding trees.

So, up in the branches, there could be prey.

(SQUIRREL SQUEAKING)

If only he could get to it.

It's six metres up.

At last, a squirrel.

Not much, but enough to keep him going.

To survive a winter in these mountains takes tenacity,

and bobcats have that in abundance.

Snow on the equator.

Unlike the Rockies,

in these mountains there are no marked seasons.

This is Africa's Mount Kenya.

It's over 5,000 metres high, which makes its summit

some 30 degrees colder than the surrounding savannah.

Giant heathers, lobelias and groundsel grow on its upper slopes.

They all thrive in the tropical sun.

After all, every day is summer.

But once the sun sets, every night becomes as bitterly cold as winter.

The temperature drops to five degrees below freezing...

...turning the mountainside into a garden of ice.

(CRACKLING)

Everything freezes.

But the cabbage groundsels have a way of protecting themselves.

They close up their leathery leaves to form an insulating blanket

that shields their vulnerable central bud.

Night comes to an end...

...and the sunshine returns.

The groundsels spread their leaves wide to bask in the sunshine once again.

Dawn, in the high Andes...

Here too, the rising sun brings rapid relief

to animals living amongst these volcanic peaks.

Mountain viscacha are up early to claim the best places

to catch the sun's first rays.

For others up here, the sunrise is even more welcome.

At over 4,000 metres,

this is the highest flamingo colony in the world.

At night, it gets so cold that even this salty water freezes over.

And now the flamingos are trapped in the ice.

Eventually, the sun thins the ice.

But it's still a struggle for the flamingos to break free.

Walking on thin ice is always risky.

And it's hard to retain one's dignity,

especially when you're wearing stilts.

At these altitudes,

the sun's power can quickly turn from salvation to threat.

The atmosphere is so thin,

there is very little protection from ultraviolet radiation.

By mid-morning, it's risky to linger out in the open.

The viscacha are forced to head for the shade.

Out on the lake, there is nowhere to hide.

The white crust of the Soda Lake reflects the sun's glare

and increases the impact of its ultraviolet rays.

By mid-day, uncovered human skin will burn in four minutes.

But this doesn't seem to bother the flamingos.

In fact, they are on parade.

(SQUAWKING)

During the breeding season,

the flamingos perform these peculiar courtship dances

even through the hottest time of the day.

They're so eager, they don't even pause to feed.

The rules are something of a mystery, but after a month of dancing

all the birds will have paired off and will be getting ready to mate.

Up here, there are few other creatures to bother the flamingos.

But then, few other creatures could even tolerate these conditions.

So, for animals that have the endurance,

mountains can be sanctuaries.

But rocky peaks, which to us, perhaps, seem a symbol of permanence,

are more fragile than they appear.

Today, in the Alps,

human encroachment is changing even the highest summits.

In the Rockies, rising temperatures are shortening winter hibernation

and stifling the growth of valuable food plants.

And in the Andes, some glaciers have shrunk

by 50% in just 30 years.

Even the Himalayas are now vulnerable.

With most of the world's tallest peaks

and covering a million square kilometres,

this is the greatest mountain range of all.

And here, temperatures are now rising faster than the global average.

As the snow line retreats further and further up these peaks,

there is less and less space for wildlife.

And that is a challenge

for one of the most majestic of all mountain creatures.

(WHOOSHING)

The snow leopard.

Seldom seen.

The detail of their lives has long been a mystery.

But now at last, helped by the latest remote camera technology,

we're getting closer to them than ever before.

They're very rare.

Only about four of them in a hundred square kilometres.

There is simply not enough prey to sustain more.

(SNIFFING)

They live solitary lives.

Nonetheless, they are well aware

of the presence and the movements of their neighbours

because they leave messages in a few special places.

They rub particular rocks with their cheeks.

And they spray them with urine.

The two perfumes create a unique signature.

Any other leopard can know which of its neighbours passed this way,

without ever making direct contact.

But there are times when snow leopards must come together

and the event is often violent.

An adult female and her daughter.

She has devoted the last two years to raising her cub,

and very soon, it will be weaned.

For now, the cub is still entirely dependent on its mother.

But staying together as long as this could cause problems.

The female is now in heat again,

and any male that smells her signature will know that.

From this moment on, her cub's life is at risk.

Males kill cubs that are not their own.

But the mother is now driven by an urge that she cannot control.

She lets the males know exactly where she is.

(GROWLS)

From up here, she can be heard from miles around.

(GROWLS)

A young male emerges from the wilderness, eager to find her.

Snow leopards meet so infrequently that there is uncertainty and tension.

(GROWLING)

And it's about to get worse.

(LOW GROWLING)

Another bigger male has arrived.

The mother and cub are trapped between the rivals.

The cub is now in danger. Mother must act fast.

To divert the males' attention from her cub,

she rolls over submissively.

With the males fixed on the female, the cub has a chance to escape.

The males close in on the mother from both sides,

keen to claim her for their own.

A fight is inevitable.

(GRUNTING)

The female moves to escape and protect her cub.

But the big male follows her.

He will not let her leave until he has mated with her.

With the males gone, the female is at last reunited with her cub.

But she has been injured.

The cub, however, is alive, thanks to its mother.

Until her injury heals, she won't be able to hunt.

Mountain animals survive on the very edge of existence.

Mother and cub were not seen again.

Until, over a month later,

high on a ridge, a remote camera was triggered.

The female cat.

She's no longer limping but she's now alone.

Then an hour after the female has left, the camera is triggered again.

It's her cub, taking her first steps towards adulthood and independence.

She is unlikely to see her mother again.

But every now and then, they will be reunited

through the messages they leave on the marking rocks.

Her mother has succeeded in raising her,

but life ahead will be challenging,

and she will spend nearly all of it alone.

Only the toughest can survive

among the savage beauty of the world's highest mountains.

Next time, we explore the world's jungles.

Places of surprise and invention unrivalled on Earth...

where the battle for survival is at its most intense.

(THEME MUSIC PLAYING)