Original subtitles

The Polar Winter

This is the planet at its most hostile.

Those that stay here at this time must face the harshest conditions on Earth.

The High Arctic in late autumn, empty and abandoned to ice and snow.

Most animals migrated south weeks ago. The few that stay

will face violent winds, plunging temperatures and months of

darkness.

A female polar bear searches for shelter.

Other bears are out on the frozen ocean looking for

food, but she won't feed again until next spring.

Using as little energy as possible, she starts to dig a shallow nest.

The snow here is easy to work. It's soft and light, a sure

sign that soon plenty more will accumulate on this slope as

winter advances.

And that is what she needs.

If she has chosen well, the Arctic wind will do much of her work for her.

Once the snow here is deep enough, she will dig down to make

a den. She'll then lie waiting for her cubs to be born as

winter sets in.

The sea ice already covers twice the area it did in summer.

Those animals that a few weeks ago came down here to feed in

the sea are now locked out.

But there are windows in this white desert, gateways to the rich ocean below.

Most birds have migrated south, but in the frozen Bering

Sea, ducks of one particular species are gathering together

in a single immense flock.

Spectacled ideas, hundreds of thousands of them.

With the seas that fed them throughout the summer,

all but frozen, this is the Ida's last refuge.

Such patches of open water, kept free of ice by

strong currents, are given a Russian name, Polinyas.

If this Polinia stays open all winter, the ducks will

have avoided an exhausting migration. It's a gamble and a

tremendous risk, especially for the spectacled Ida,

for this Polinia holds the world's entire population.

Surrounded by ice, the spectacled Ida's survival depends on

this single vulnerable oasis, and conditions here can change

very fast.

A smaller pool. Here, common Ida ducks are learning a bitter

lesson. An early winter storm has caught them out and the

ice is closing in. But the pool is shrinking

and the ducks are freezing to death.

These gamblers have lost.

As the sun's influence continues to dwindle here in

the north, the cold pushes south into arctic lands.

Winter brings a devastatingly destructive force, frost.

Ice crystals form as moisture in the air freezes. Inside

plants, the same thing is happening to the water in their

cells and their sap.

With these first frosts, most plants die, their insides ripped apart by ice crystals.

Coniferous trees, however, like fir and pine, can withstand very low temperatures.

It's these trees that create the greatest forest on our planet. This is the taiga.

It encircles the globe and contains one third of all the trees on earth.

As winter deepens, frigid air from the arctic meets warm

moist air from the south, producing particularly heavy

snows.

For the big animals of the forest, there's no way of hiding from the winter.

But size for the bison of northern Canada is in fact their

salvation. Big bodies lose less heat and can carry more

insulation. That may be why these bison are the largest land animals in North America.

And only a large predator can tackle them.

Wolves hunt better in packs, but there are only two

of them here and the prey they pursue are giants.

A vast arctic wilderness stretches all around. In it, somewhere, there are bison.

These deep tracks in the snow are easy to follow, but which way were the bison going?

They have detected a scent. The hunt is on.

Running in the bison's tracks is easy. The snow here is

compressed and firm. At this rate, the wolves will soon

catch up.

They attempt a shortcut. The giant bison can plow on through

virgin snow. But for the wolves, deep snow is a hindrance

and now they're losing ground.

The hunters rejoin the bison's tracks and the contest is on again.

The bison are the only prey here in winter. The wolves have

no option. They must tackle them. But bison are ten times

their size.

In winter, the line between life and death is so narrow that

for a wolf, even a small injury could be fatal. It's crucial

they select the right target. This one is very big. Good decision.

This is smaller, a yearling. Even though it's young, it's

nonetheless heavier than both wolves combined and it is

extremely powerful.

The male wolf backs off. Perhaps he's frightened of injury,

but the female is more determined or more desperate.

Having given so much already, she must make the kill.

This is a battle of life and death for them both.

The bison has no strength left. The battle is over.

Winter deepens. The snow continues to accumulate, smothering the forest.

Some trees are loaded with three tons of snow. It shuts

out what little light there is at these latitudes and that

shortens the growing season still further and

limits how far north trees are able to grow.

So snow influences both the shapes of the trees and the extent of this forest.

And it affects the animals too.

It helps to have friends if you want to find food for this

time of the year. Wolverines and ravens, a match made in the

tiger.

It's the hardest time of the year to find food, but the

Wolverine knows that a raven's call is as good as a dinner

bell.

And the raven has just recruited the best can opener in the forest.

The moose carcass is frozen solid, but the Wolverine has

immensely powerful jaws, well able to deal with frozen food.

The raven's bill is more suited to leftovers.

The raven has to be patient.

A Wolverine's appetite is legendary. According to folklore,

it can eat more at one sitting than any other creature in

the forest, hence its other name, the glutton.

What the Wolverine can't eat now, it stores in the deep

freeze. It will bury these food parcels across the forest,

planning ahead for leaner times.

For a few, the snow is an ally.

Voles stay active throughout the winter beneath

the snow, despite the freezing temperatures above.

Traveling along tiny corridors, they move from pocket

to pocket of perfectly refrigerated food. Snow is

a great insulator, so down here the temperature never falls

more than a degree or so below zero, and that's warm enough

for a vole to thrive, even if it lacks the stature of a bison.

In some years, vole numbers boom, and then they're

forced to break cover to search for more food.

Music It's a silent and very skillful hunter,

but deep snow can be beyond its reach.

But such snow is no barrier to one predator.

The least weasel, 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 the weasel can't follow.

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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.

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

And now she puts it all together to make a cozy

blanket under which to sleep in her den below the snow.

Midwinter in the northern forests. The sun

is so low that it's twilight at midday. Music

Farther north in the high Arctic, the sun has been below

the horizon for months, and it'll be several more before it

appears again.

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The male polar bear spends winter out on the frozen ocean.

Few creatures can endure these conditions.

If he's lucky, he will find a carcass that could provide a

little food, possibly that of a fox or another polar bear.

But otherwise, he must live on his reserves.

This is a time to scrape by, to wait.

But on these side slopes, beneath the snow, new lives are beginning.

The cubs are born blind and tiny, and early

birth is easy on the mother, who is barely awake.

Despite her sleepiness, her instinct to nurse is overwhelming.

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The cubs' clucking calls stimulate her to produce milk. And

what milk? It's nine times richer than her own, and enables

her to double their weight every few weeks.

Music But for now, they lie protected within their icy cocoons.

Music

A hundred miles above the earth, the aurora lights up the sky.

After traveling 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 borearis, 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

may be, but no warmth that will help the emperor penguins.

The Arctic winter is brutally cold, but in

Antarctica, the darkest months are even more savage.

The male penguins have not eaten for months, and

have only each other for protection from the gales.

Each has been entrusted with a single precious egg, balanced

on the top of its feet. If the egg were to drop onto the

ice, even for a moment, the chicken side would

die, and all this would count for nothing.

The emperors are not entirely alone.

The Weddell Sea, the only mammal to remain here throughout the winter.

They must have breathing holes, and so have to constantly

scrape away the ice that threatens to close them, rasping

away fresh build-ups with special wide-gaped jaws.

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.

Of course, animals must still be hardy. These Borgravinke

fish have antifreeze in their blood, so they're untroubled

swimming among the ice crystals.

Many animals here are remarkably long-lived, perhaps because

the conditions are so stable. Some sponges could be a

thousand years old and large enough for a human to hide

in. There could hardly be a greater contrast to the bleak,

windswept world just above. The Borgravinke

fish live in the Borgravinke Basin, in the Borgravinke

Basin. But there is a constant danger here.

Swirling patterns in the water reveal its presence. They're

made by brine, super concentrated saltwater. It's a warning.

New sea ice forming above leaves behind brine

that is so extremely salty it sinks rapidly.

As it descends, the seawater around it freezes instantly

and forms a sheath of ice, a brineicle that grows downwards

towards the seafloor.

Winter is reaching down from the cold world above.

As it touches the seafloor, it kills whatever living

thing it contacts by encasing it in a tomb of ice.

Even in the relative warmth of the water, the lethal

cold of winter threatens life on the seafloor.

Another, more constant attack rises from below. Pressure in

the depths keeps water liquid even though its temperature is

far from freezing.

Currents bring up this colder water and it turns to

ice, covering everything that can't move away from it.

And then the ice, being lighter than water,

begins to float, lifting away anything attached.

Even some of the faster moving animals are caught.

So the ice cleanses the seafloor and screws the

ceiling above with remnants of life from below.

A sign that winter is nearly over.

The songs of male weddle seals challenging their rivals to battle.

The male seal's calls can be heard over 15 miles away.

He aims to control the best breathing holes, for

they will determine his mating rights in spring.

His calls create powerful shockwaves in the water. They're threats.

This hole has already been claimed and the owner will not surrender it willingly.

No change this time. The challenger will need to find a hole with a weaker owner.

The battles continue until the females arrive and that time is now close.

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. Far away, the males are waiting.

While the females were gone, the sea ice grew and it's

now twice the distance from its edge back to their colony.

Seventy miles away, the males are in desperate need of help.

Despite doing all they can to conserve their

energy, many are close to dying from starvation.

Reunited after three months apart.

The reward for her return, a first glimpse of her chick.

The reunion made, it's time for the handover.

The father finds it hard to let go.

Some gentle persuasion is needed. He has endured the most

appalling conditions on Earth to ensure the survival of his

chick and the bond is strong. The exchange must be quick

as the tiny chick, unprotected, could freeze to death in

seconds.

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. Her mission is complete.

But for other mothers, the journey ends in disappointment.

Their chicks have not survived.

The females need to nurture remain strong. Any chick that

strays from its parent is at grave risk of being kidnapped.

The chick's mother, the chick's mother, the chick's mother, the chick's mother,

the chick's mother, the chick's mother, the chick's mother,

the chick's mother, the chick's mother, the chick's mother,

the chick's mother, the chick's mother, the chick's

mother, the chick's mother, the chick's mother,

The chaos may be a consequence of frustrated

parental urge, but the outcome can be tragic.

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

remain to raise their young. And now it is they who

will benefit most from the rich southern spring.

Another arrival is the certain confirmation that spring

is here. The Adalys, having spent winter at sea, have come

back, but they have not even mated yet, let alone laid their eggs.

Now, at last, the male emperors can return to where they are most at home.

One season ends and another begins. The penguins will soon

be joined by migrants and the far south will bustle with

life for a few frantic months.

But there are only a special few, north and south, who

can survive winter at the farthest ends of our planet.

More than any other season in the poles, winter was to pose

the greatest challenge to the frozen planet crew. The team

endured winds of over 100 miles an hour and temperatures as

low as minus 50 degrees centigrade. Their boats were trapped

in sea ice for days, while bears trapped others indoors.

Some of the coldest conditions experienced were near the

Arctic Circle in northern Canada. In winter, temperatures

dropped to minus 40 degrees and stayed there. On the edge

of the vast tiger forest, the team hoped to film one of the

most remarkable predator-prey relationships on the planet.

What they experienced was a struggle against the elements.

What they witnessed was a more profound struggle for life and death.

Wood Buffalo National Park covers 28,000 square miles, the

size of Denmark. One of the few cameramen to have filmed

wolves and bison here is Jeff Turner. I first tried to film

bison and wolves in this national park 15 years ago. And

getting around on the ground is incredibly difficult at any

time of the year, but in the winter, it's tough. We quickly

realized that the only way we were going to get anything

here was we had to get up in the air. The Frozen Planet team

had never attempted aerial filming in such low temperatures.

The first challenge for director Chattin Hunter was

protecting the sensitive aerial camera at minus 40

electrical cables short-circuit like fireworks.

Aerial cameraman Michael Kellam comes from sunny

California and has never experienced temperatures so low.

Operating delicate controls while wearing gloves is not

easy. A computer and joystick are needed to control the

aerial camera attached to the outside of the helicopter.

Michael would have to choose between dexterity or warmth.

With their camera mounted on the nose, the aerial team could

now fly hundreds of miles in search of the animals. Jeff,

meanwhile, is still on foot scouting the other side of the

national park. I wonder what Jeff's getting on the ground.

Oh, man, it's cold. With the wind today, it's about minus

37, so we've got to keep these heaters in here, keep the

camera running at these temperatures. From 3,000 feet up,

Chattin catches a glimpse of the elusive wolf pack. I can

see wolves, I can see wolves near Buffalo. 10, 15, that's a

big pack. We've got a big pack of wolves here. The wolf pack

turns out to number an extraordinary 25 individuals, one of

the largest ever filmed. There's two more walking in from

the left. And it looks like they're already on the hunt. The

helicopter allows the team to shadow the wolf pack without

disturbing them. Let's go back into that nice, slow circle.

I'll be around them. They look pretty determined. The pack

are moving in on their prey, and the aerial team are perfectly placed.

They're making their move. That's Buffalo on the move. The

chase is on. Extreme concentration is now needed, both from

the pilot and the cameraman, to keep the shot smooth.

There's more coming in now. Nice and tight, a little pack

challenging them. We've got a nice shot of the pack, the

wolves coming up in the pack. OK, have they still? Yeah, I

got them here. I'm just going to bring it up a little bit.

OK, OK, OK, I'm going to tighten up just a hair. OK. I just

want to get a true shot of the wolves in the back of the

pack. The wolf pack have picked out a young bison. Oh, holy

****. As Michael struggles to hold the shot steady, no one

is prepared for what came next. Oh, the other guy just

knocked him down pretty much. A one-ton bull charges

through, taking out both the wolves and the young bison.

I've never seen anything like that in a while. It's

unbelievable. The team have filmed extraordinary new

behaviour from the air, but Geoff was nowhere nearby. To

complete the sequence, they will need to work together. Only

by using the helicopter to position Geoff will they be able

to get both air and ground coverage.

This pack will now feast for days, so the crew must move on.

Geoff takes the team deeper into the wilderness in search of

a new wolf pack. With everyone on board, there are more

eyes for spotting. Bison on the run can only mean one thing,

wolves, but this time only a pair. Geoff must anticipate the

animal's every move and direct the helicopter to where he

needs to be dropped off.

Had to figure out exactly where the buffalo were going to

run and try to get there ahead of them. If I got dropped off

in the wrong position, we would blow it. There wasn't going to be a second chance.

That moment when you get out of the helicopter and it leaves

you behind, you feel an incredible sense of isolation.

They're coming in now. When I saw the herd coming around the

corner, I knew we'd picked the right spot. I was right in

front of them. When the buffalo are running right

towards you, it definitely does get your heart pounded.

The bison have poor eyesight and can't see Geoff. It's now a

test of nerves. Weighing one ton and running at 40 miles an

hour, one wrong step and the bison could kill Geoff. At the

last second, they spot him and three peel away to the other

side.

At the back of the herd, the wolves have closed in. Look

at Adam. They're trying to separate that little one.

Got it, got it? Both wolves are on him.

What followed was one of the most emotional and powerful

scenes the Frozen Planet team were ever to film. Geoff has

picked his position perfectly. He is now only 50 meters

from the animals and able to film a truly epic battle. I had

never been so close to a wolf and bison battle. I could hear

them breathing. The power of the buffalo, the way he just

threw this wolf around like it was a rag doll. I

couldn't believe the beating this wolf was taking.

The struggles that we'd had with the winter and the cold and

the snow just felt so insignificant compared to these two

animals that were struggling for their very lives.

For over an hour, I watched this wolf and bison battle

each other to a standstill. They were both unbelievably

exhausted.

Watching these two animals engaged in this massive life and

death struggle was one of the most powerful things I'd ever

witnessed in the wild.

As a filmmaker, you're definitely torn watching something

like this. You know you need to keep filming and you know

this is a natural event, but it's also incredibly sad to

know that one of these two magnificent animals isn't going

to make it.

The bison is fatally wounded. The battle is over.

The team have managed to capture a remarkable hunt from both

ground and air. All of them have been humbled by witnessing

an extraordinary winter struggle for survival.

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