All language subtitles for BBC Frozen Planet E08 The Epic Journey

The polar regions are the coldest,
most extreme places on our planet.

Winds reach 200 miles an hour

and temperatures drop as low as
minus 70 degrees centigrade.

Only the toughest can survive here.

Over the course of a year,
polar animals must overcome

not just the cold, but the most
extreme seasonal changes on Earth.

In the High Arctic, winter is one
long night that lasts for months.

On lee-side slopes, beneath
the snow, new lives are beginning.

The cubs are born blind and tiny.

An early birth is easier on
the mother, who is barely awake.

Despite her sleepiness, her instinct

to nurse is overwhelming.

CUBS SQUEAK

The cubs' clucking calls

stimulate her to produce milk.

And what milk!

It's nine times richer than our own,

and enables her to double

their weight every few weeks.

The sun is returning after
an absence of nearly four months.

And its warmth starts to transform
this magical ice world.

Spring has arrived.

The greatest seasonal change
on our planet is now under way.

Antarctica is still locked in ice,

and surrounded by a frozen ocean.

Nonetheless,
there are signs of spring.

Adelie penguins are arriving.
Just the males.

They've spent five months at sea,

where it's warmer than it is
on land,

and now they're in a hurry,

for spring will be short.

They have travelled 6,000 miles
across the ocean

since leaving their colony last year
and now, they're returning to breed.

They cannot lay their eggs on ice
for they would freeze.

So they have to come here,
where there is bare rock.

Over the coming months,

the few parts of Antarctica
that are ice-free will be the stage

on which five million Adelies will
build their nests.

To construct one, they need pebbles.

And without a good-looking nest,

a male will be unable to
attract a female.

When they at last arrive.

An impressive property demonstrates
your worth as a mate.

It takes stones of all shapes
and sizes to build a decent nest

and finding ones that are
just right is not easy.

So, some penguins turn
to a life of crime.

The one who has been robbed
seems unaware

that the thief is just over his
shoulder and looking for more.

The thief's nest is coming along
nicely, probably because

he keeps a particularly
sharp lookout for robbers.

After all, it takes one to know one.

By fair means or foul, the males
must finish their nests quickly

if they're to raise a family
over the short Antarctic summer.

In the north of our planet,

the weak sunshine is a welcome
relief after the months of darkness.

Finally, it's time for polar bear
families to emerge from their dens.

This is not the easiest place

to take your first steps.

And the little ones will need plenty

of encouragement from their mother.

If she can raise all three
to independence,

it will be a rare achievement.

During the months underground,
all they've known is their mother.

Now, the big, wide world holds
all sorts of challenges

for these brave, young explorers.

The mother leads her new family out
over the frozen sea

to hunt for seals.

But the spring melt
is already under way.

All across the Arctic, the sun's
warming effect is increasing.

Sea ice is showing
the first signs of weakening.

Inland, the northern rivers are
still locked in ice.

The frozen waterfalls are like dams,
holding back billions of tonnes

of fresh water that has not moved
for almost six months.

CREAKING

The vast watershed lies motionless.

But as spring advances,

it begins to stir.

The frozen waterfalls start
to weaken.

Above them,
the pressure is mounting.

Now, from high above, whole sections
can be seen to be on the move.

The waterfalls are straining
to hold back the force

that is building up above them.

The dam bursts...

..and the river is unleashed.

These vast floods accelerate
the breakup.

Soon, an area of sea ice
the size of Australia

will vanish from the Arctic Ocean.

The spring melt breaks the ice
for visitors.

Narwhals.

The unicorns of the North are on
a mission to reach

the new fishing grounds in the bays
that have been frozen up all winter,

but are now opening up.

To get to them,
the narwhals must travel down leads,

temporary cracks in the ice.

But these new roads could close
at any time,

cutting off the air
that they need to breathe.

The road narrows, until there's
barely room for one-way traffic.

Then, a surprise. Narwhals
coming from the other direction.

It's a stand-off. Each team faces
an armoury of sharp tusks.

Finally, one side concedes.

And everyone continues
in the same direction.

The melting sea ice reveals
open ocean.

And the changes on land are
no less dramatic.

Beneath the snow,
life is already stirring.

The Arctic tundra is unveiled.

Water that has been locked in ice
all winter

once again flows freely.

A landscape that was only white
now bursts with colour.

Migrants begin arriving
from the south

and, suddenly, the tundra is alive
with new families.

These Arctic wolf cubs are
just over a month old

and always looking out
for their next meal.

Their parents have been hunting.

Their offerings are devoured
instantly.

Arctic hare is a mainstay
of the tundra diet

and one the cubs seem
particularly keen on.

Uneaten food is usually hidden
for leaner times,

but there will be no leftovers
today.

The cubs are growing fast
and are always hungry.

The good times are certainly back,
but these white wolves remind us

of the Arctic's less welcoming side.

Their coats are pale to conceal them

during the long, snowy winter.

It's easy to forget
that one month ago,

this land was
a barren, white desert.

But finding a decent meal here
is never easy.

The parents travel up to 80 miles
in a day in search of

more substantial prey
for their growing family.

Musk oxen are immensely powerful.

And their sharp horns can kill.

But a calf is more vulnerable.

The two wolves work together
to split the herd

and isolate their victim.

It seems that the wolf cubs will,
at last, eat well.

But the herd regroups.

The cattle ride to the rescue.

The wolves cannot penetrate
the wall of horns.

The herd are protecting their calf.

For the musk oxen, it's all for one

and one for all.

It's a struggle for all polar
animals to feed themselves

and their families
in the brief Arctic summer.

But there is one tiny creature
of the tundra that has found

an astounding solution
to the shortness of the season.

The woolly bear caterpillar.

It's always the first insect
to appear after the snow's retreat.

The caterpillar then eats as fast as
it can and, indeed it must,

for this far north,
summer only lasts a few weeks.

The days shorten only too soon,
but the caterpillar has not yet

got enough reserves
to transform itself into a moth.

It can't leave the Arctic,
for it can't fly.

So, it settles down beneath a rock.

The sun's warmth rapidly dwindles.

Beneath the rock,
the caterpillar is out of the wind,

but the cold penetrates
deep into the ground.

Soon, its heart stops beating.

It ceases to breathe
and its body starts to freeze.

First, its gut. Then, its blood.

After four months of darkness,

the Arctic begins to thaw.

And the caterpillar rises
from the dead.

By the time the first shoots of
willow appear in the early spring,

the woolly bear is already eating.

But no matter how fast
the woolly bear eats,

it will not have time to gather
enough food this year either,

and the cold closes in once again.

Year after year, the caterpillar
slows down in the autumn

and then freezes solid.

But, eventually,
a very special summer arrives.

This one will be its last.

It's now 14 years old.

The world's oldest caterpillar.

Its remaining days
now become frantic.

It starts to weave a silk cocoon.

Inside, its body is changing

into one that can fly and search.

Abilities that will be crucial
in the days ahead.

All across the Arctic,
moths are emerging.

After completing
their 14-year preparation,

they now have just a few days
to find a partner and mate.

No life illustrates more vividly
the struggle to survive

in this most seasonal of places.

In a matter of weeks, the north
will be frozen over once again.

At the southern end of our planet,

Antarctica is still surrounded
by sea ice.

The Antarctic spring arrives first
at the outer islands.

Although the beaches
of South Georgia are now ice-free,

the King Penguins face
a new challenge.

Their peaceful waterfront has turned
into an obstacle course of blubber.

The elephant seals have arrived.

The beachmaster's authority is
being challenged.

This rival means business.

The beachmaster owns the females
here and must to fight keep them.

The beachmaster himself weighs four
tonnes, but this rival is his equal.

The beachmaster has won
the first battle,

but he may have to defend his harem
every hour for the next month.

If he can stay master of his beach
for this period,

many of the young born here
next year will be his.

In summer,
the Southern Ocean bursts with life.

No bird is more at home in water,
and they are masterful surfers.

Penguins are found only
in the Southern Hemisphere.

They can't fly, but they don't need
to. There are no polar bears here.

These are Gentoo Penguins.

Each spring, they come ashore to lay
their eggs and rear their young.

Their hungry chicks demand

so much seafood that
both parents have to go fishing.

And fishing can be dangerous.

A southern sea lion.

It uses the speed of a breaking wave
to catch up with the Gentoos.

Sea lions normally eat fish,

so he's used to catching
streamline swimmers.

But the Gentoos seem more
than his match out at sea.

He must change tactics.

Perhaps it would be easier
in the shallows.

But, no, it seems
penguins are uncatchable in water.

How about on land?

The penguin's wings,
so powerful for swimming,

are of no help
when it comes to running.

Now, surely,
the sea lion has a chance?

But on the beach,
both are like fish out of water.

Rarely do hunter and hunted play
their roles with so little skill.

The outcome is anyone's guess.

Every summer,
over 40 million penguins

take to the Southern Ocean to feed.

They're joined
by thousands of whales.

Minkes are the most numerous.

They all come here to harvest
the richest ocean on Earth.

Southern humpbacks have travelled
4,000 miles from the equator

to get here in time
for the Antarctic summer.

Each year, the sea ice
that surrounds Antarctica melts,

effectively halving the size
of the continent

and exposing rich waters
around its coastline.

It's the most spectacular
seasonal change occurring

anywhere on our planet.

The remnants of the sea ice are
occupied by sunbathing seals

that have been here all winter.

But new arrivals are following
the retreating ice edge.

And they have come here to hunt.

Killer whales.
The ocean's top predator.

Killers are like wolves,

for they will hunt animals
far larger than themselves.

But even smaller prey are a problem

if you can't reach them.

The solution is teamwork.

Swimming in perfect formation,
they flick their tails in unison

and create a wave
that cracks the ice.

They regroup and assess the damage.

A more powerful wave is needed.

The ice floe is breaking up.

Now, they are close enough to get
a good look at their target.

The seal is a crabeater,
sharp-toothed and feisty.

Not their favourite.

The wolves of the sea move on

in search of easier quarry.

A Weddell seal, that's better.

These are more docile
and easier to tackle.

The pod stays close together
and travels silently.

This time, they unleash
a far more powerful wave,

and with astonishing accuracy.

These big waves are not intended
to break the ice,

but to knock the prey into
the water,

and they rarely fail.

The seal is now where
the killers wanted.

But the hunt is far from over.

They need to grab their prey
by the tail,

while avoiding its snapping jaws.

Only then will they be able
to pull it down and drown it.

Side swipes create violent,
underwater turbulence, a new tactic.

Blowing bubbles gives cover for
others to lunge at the seal's tail.

Somehow, the seal manages
to reach a tiny ice floe.

The killers could easily grab it,

but now, this seems
to have become a game.

The seal's life hangs
on a roll of the ice.

Yet again, the pod joins forces
to dislodge the seal.

The seal sees a chance to escape.

Exhausted, it no longer has
the energy to pull itself to safety.

And the killers are moving in.

Game over.

As the Antarctic summer draws to an
end, visitors that rely on the brief

flush of food will soon be forced
north by the return of the sea ice.

For the largest land predator, the
sea ice cannot return soon enough.

The end of the Arctic summer and
the sun hasn't set for three months.

It's hard to imagine the bitter cold
will soon return.

Some will welcome the chills
of autumn but, for most,

time is running out before they will
have to retreat to the south.

The shorter days
and colder nights trigger

a dramatic change in the willows
and blueberry bushes.

They stop producing
the green pigment that harnesses

the sun's energy, and red and yellow
pigments build up in their leaves.

The tundra blazes with colour

and the whole landscape is
transformed.

The sound of autumn.

The musk ox rut has begun.

This clash of polar titans could
easily become a fight

to the death, as males battle
over females.

A heavy skull and helmet of horn,
four inches thick,

provide some protection
for the musk ox's brain.

The impact is like a car crash
at 30 miles an hour.

Over the next half hour,

the advantage ebbs and flows,
as each tries to finish the duel.

If one can turn the other

and gore its flank,
the fight will be over.

The stakes rise as the risk of
injury, or even death, increases.

This male is outmanoeuvred.

And the champion returns
to claim his females.

By now,
most animals have migrated south.

But the musk ox,
with their thick coats,

will stay
and face the approaching winter.

The moisture in the air freezes
and hoarfrost decorates the leaves.

Ice crystals grow like shards
of glass on every twig.

As the sun's influence continues
o dwindle here in the north,

the freeze pushes
into the tree line,

spreading over
one fifth of the planet.

The northern forests
lock down for winter.

The last running water freezes
and cathedrals of ice are formed.

The great waterfalls of the north
shut down.

The stage is now set
for a magical event.

The formation of snowflakes.

Cold air meets warm air
from the south

and the moisture it carries
crystallises.

All have a six-fold symmetry,

but no two have ever been found
with exactly the same shape.

Each snowflake is water waiting
to be released in spring.

For this reason, snow is the
life blood of these silent forests

and all that live here depend on it
in one way or another.

Some, like the Great Grey Owl,

appear in spring for the boom times,
then vanish like phantoms.

Stooped, shrouded figures bear
the weight of winter's heavy snows.

The heavy snows make it

hard to get around,

even for the largest and

most powerful wolves in the world.

Today, they are setting out to hunt.

The pack is 25-strong,

a sign that the prey
they are seeking is formidable.

The largest land animal
in North America.

Bison.

The bison form a defensive circle
around their young,

horns pointing outwards.

The wolves need a bison
to break rank.

But the tables are turning
and now the wolves have to retreat.

The pack focus their attention
on the rear of the herd

and the bison begin to panic.

A young bison falls behind.

Even this yearling dwarfs
the wolves.

Running head down,

the herd's only thought is escape.

A stroke of luck for the wolves.

The kill will feed the pack
for several days.

But then,
they will have to resume the chase.

At the frozen ends of our planet,

the struggle for survival
never eases.

For a few, the snow is an ally.

Voles stay active throughout
the winter, moving between pockets

of perfectly refrigerated food
in a network of tunnels.

These tunnels are a sanctuary
from predators.

Except one.

The least weasel is a tiny hunter

and the vole's nemesis.

Its body is exactly

the same width as a vole's,

so there's nowhere a vole can go
that a weasel can't follow.

The weasel's long slender shape is
perfect for hunting in tunnels,

but the worst possible shape
for staying warm.

So, they need a special way
of doing that.

She plucks the fur from its body,
tuft by tuft.

And now, she puts it all together
to make a cosy blanket,

under which to sleep in her den.

100 miles above the Earth,
the aurora lights up the sky.

After travelling millions of miles
across space, solar winds, attracted

by the magnetic pull of the Poles,
collide with the Earth's atmosphere.

Trillions of charged particles
dance across the sky.

Above the Arctic, the aurora
borealis, the northern lights.

In the south,
it's the aurora australis,

the southern lights, that bring
light to Antarctica's long winter.

These spectacular light shows
are only a tease.

Solar energy maybe, but no warmth
that will help the Emperor Penguins.

The male penguins have not eaten
for months and have only each other

for protection
from hurricane-force winds.

They have been deserted
by the females, left to incubate

their eggs throughout
the worst winter on Earth.

The Emperors are not entirely alone.

The Weddell seal.

The only mammal to remain here
throughout the winter.

Beneath the ice, they are beyond the
reach of the bitter winter winds.

The sea is minus two degrees
centigrade.

A warm bath compared
to the conditions overhead.

The roof of ice insulates this world

from the wild fluctuations above.

The temperature down here has barely
changed for 25 million years.

There could hardly be
a greater contrast

to the bleak, windswept world
just above.

But there is a constant danger here.

Swirling patterns in the water
reveal its presence.

They're made by brine,
super-concentrated salt water.

It's a warning.

New sea ice forming above
leaves behind brine

that is so extremely salty,
it sinks rapidly.

As it descends, the sea water
around it freezes instantly

and forms a sheath of ice.

A brinicle that grows downwards
towards the sea floor.

Winter is reaching down
from the cold world above.

As it touches the sea floor,
it kills whatever living thing

it contacts by encasing it
in a tomb of ice.

As calm returns beneath the ice,

a dramatic change is coming
to the world above.

The sun returns to Antarctica.

The longest night on Earth has ended

and winter begins to give way
to spring.

Female Emperor Penguins.

After four months feeding at sea,
they're returning sleek and fat.

Penguins, it seems,
can fly after all.

But a winter at sea has left them
a little out of practice.

There is no time to waste.
Faraway, the males are waiting.

Reunited after three months apart.

The reward for the female's return,

a first glimpse of her chick.

A task that began in autumn
has been completed.

Despite the huge odds against it,

the precious chick has survived the
winter and is now with its mother.

And she has food.

The chick's first fresh meal.

The female's mission is complete.

For those Emperor Penguins
that survive,

the worst is over for this year.

There will soon be abundant food
for everyone.

The Emperors have taken on
the polar winter and won.

The gamble has paid off.

All other animals escaped.

Only they remained with their eggs,

and it's they who will benefit most
from the rich southern spring.

Their epic journey is complete.

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