Original subtitles

Bear: These emperor penguins are about to undertake

One of the greatest feats of endurance on the planet.

A single egg.

It's taken almost all this mother's energy to create.

Time to entrust it to her mate.

While she leaves to feed at sea.

Now it's up to dad.

He must carry the egg through the world's worst winter.

(wind howling).

Risk his own life to keep the chick growing inside alive.

Just one of the many remarkable stories of how

Life triumphs at the ends of the earth.

(theme music plays).

When winter hits the polar regions,

The temperature can drop as low as

Minus 120 degrees fahrenheit.

Almost nothing grows.

Winds build into some of the strongest on earth.

You've got land and sea locked in ice.

And weeks of perpetual darkness.

Only a few remarkable animals have what it takes

To survive here, and every day is a struggle

Against the elements and each other.

(growling).

Now the poles are changing faster than

Anywhere else on the planet.

(crashing).

And getting through the coldest days,

That's just the beginning of the battle.

Late fall.

Polar bears are grounded.

Once the sea has frozen over

They can head out and begin hunting.

But since the 1970s that's taking longer.

Hunger claws for an extra three weeks.

And this young male must face other challenges.

An older rival.

(growling).

(growling).

(growling).

The largest of all land predators.

Male polar bears lead a life of violence.

But today punches are being pulled.

Sparring partners test strength and skill.

Preparing for tougher times.

When the battle for food and mates will be real.

(growling).

But first, patience.

Wait for winter.

The magic number.

28.8 fahrenheit.

Sea water begins to freeze.

An ice kingdom is born.

Almost limitless hunting grounds.

The harshest season is when polar bears thrive.

The arctic plunges into 24 hours of night.

Around the poles the planet's magnetic field puts on an

Unearthly display.

In the north the aurora borealis.

And in the south the aurora australis.

Winter here looks heavenly.

But for these emperor penguins it's hell on earth.

All of them are male.

And if the eggs they're carrying are to survive,

All of them must stand strong.

(wind howling).

Each one takes their turn in the full force of the wind.

All the time balancing their eggs on their toes.

Just beyond the ices deadly reach.

(wind howling).

(penguin call).

75 days of sacrifice finally over.

(penguin calls).

It was worth it.

(penguin calls).

Just 6 ounces, he's got a lot of growing to do.

Soon the ice on which they stand will all be gone.

This is canada's last land before the arctic pack ice.

Somehow an eight-strong pack of arctic wolves

Survives here.

(yipping).

During the brutal winter

Finding food is a daily struggle.

But after almost three months of darkness a ray of hope.

(barking).

Arctic hares are one of the few other creatures

That survive here.

Gathering in huge groups offers protection.

And now the sun has returned,

The element of surprise is gone.

♪ ♪

A lot of effort for no return.

There are bigger opportunities here,

But they come with greater risks.

Musk oxen.

One of the arctic's true survivors.

Bear: In their search for food the arctic wolf pack

Can cover 50 miles in a day.

These musk oxen have spent all winter

In this frozen waste land.

They're built to survive.

But just one adult would feed the entire pack.

To witness wolves hunt musk oxen in winter is so rare

It's never been captured on camera, until now.

(rumbling).

This herd has a youngster.

(rumbling).

(whining).

But it's protected behind a united front.

Armed with slashing horns,

Adults weight up to 700 pounds.

(rumbling).

(bellow, whining).

The wolves search for weakness in their defense.

Try to get them on the run.

(snorting).

(growling, barking).

The mother won't leave her calf,

But her instincts work against her.

(growling, barking).

(grunting).

(growling, barking).

(rumbling).

In such a brutal landscape, one animal's survival often

Depends on another's fate.

In the south, the sun's power is increasing.

(chattering, calling).

It's been 12 weeks since he hatched.

In fewer than four months, all this will have melted.

By then chicks must be ready to swim.

(chattering, calling).

His life depends on how quickly he grows.

(chirping).

In just 150 days his body weight must increase 70 times.

(chirping, calling).

Strengthening sun promises easier times.

But down here promises are easily broken.

Antarctica's freezing winds have become more ferocious.

(howling wind).

A hole in the planet's ozone layer is disrupting

The atmosphere, altering the weather.

(howling wind).

Even though dad hasn't returned from fishing,

The chick now needs so much food,

Mum must go too.

His instincts are to follow.

But it's a mistake.

He's walking away from safety.

(calling).

(calling).

Unless he makes it back to the colony,

He will die.

(penguin calls).

Bear: In antarctica a storm has hit the

Emperor penguin colony.

It's taken a heavy toll.

(calling).

But most have survived, keeping each other alive.

Separated chicks must now find their parents.

(calling).

Somewhere amongst 17,000 penguins,

Is his father.

(calling).

His call is unique.

Reunited and safe.

These chicks have learned an important life lesson.

The colony only survives by standing together.

Spring races across the arctic.

The change brings new challenges.

A young female.

She depends on seals for food.

The only prey with enough calories to sustain her.

As the ice melts, escape routes are now everywhere.

Her chances plummet.

(sniffing).

Bears have an acute sense of smell.

(sniffing).

They can detect seals from nearly 2 miles.

This one's closer.

(sniffing).

♪ ♪

(cawing).

News of her kill carries on the wind.

A huge male, he needs food too,

And he doesn't care how he gets it.

(grunting).

(cawing).

(roaring).

Just bones.

She's taken her fill.

Now she must leave.

A hungry male polar bear can turn cannibal.

Summer in the poles has always been a time of transformation.

But now the arctic is changing faster than

At any rate in recorded history.

The climate is warming.

Polar bears face immediate survival choices.

Head deeper in to the ice or swim for land.

Either way four lean months lie ahead.

Climate change at the poles will bring challenges for

Many, but for some it's opportunity.

Over 50 years the average temperature here has risen

By around 5 degrees fahrenheit.

Gentoo penguins like it warmer than their

Ice loving emperor cousins.

It exposes the bare rock they need for nesting.

The waters here are so rich successfully raising

Two chicks is far more likely.

(chirping, calling).

Who'll feed first is decided by a chase.

(chirping, calling).

Chicks are at all stages.

The oldest are ready for the sea.

But they're first taste of the ocean may also be their last.

Bear: A changing climate around antarctica is helping

Gentoo penguin populations.

But even in summer conditions can deteriorate rapidly.

Storms blow brash ice into shore.

The route back to the colony is blocked.

Fledglings must negotiate a maze of floating ice.

It's all too easy to get left behind.

(chirping, calling).

And that's not the only danger.

Pushing through brash ice is hard work.

But this is not a safe place to rest.

♪ ♪

Panic drives them on.

(chirping, calling).

A leopard seal.

A 12 foot long penguin predator.

Attention turns to the straggler.

The more he struggles, the easier he is to find.

♪ ♪

Leopard seals like to toy with their victims.

With so much prey about, there's no rush.

(calling).

♪ ♪

(calling, growling).

A last act of defiance.

(chirping, calling).

The one that got away.

Still, there's plenty of other penguins to play with.

Summer intensifies.

Ice continues to retreat.

Polar bears are stranded.

Their toughest time.

Surviving on fat built up last winter.

Reserves are running low.

There's almost nothing to eat.

Almost.

(sniffing).

At this time of year beluga whales arrive

In canada's shallows.

A sanctuary for newborns.

These waters can be 18 degrees warmer than the open sea.

(clicking, whistling).

This could be his life line.

They're tantalizingly close.

(squeaking, clicking).

One of the few whales with flexible necks.

The belugas easily see him coming.

With each dive, he wastes precious energy,

And his chances of surviving summer get slimmer.

Ar: On the shores of hudson bay a hungry polar bear is

Desperately trying to hunt beluga whales.

Catching them in open water has proved almost impossible.

(squeaking, clicking).

But he can't let this opportunity slip away.

A change in tactic.

From the rock prey is easier to spot.

If only they would come in range.

Built for the cold, suffering in the sun.

♪ ♪

Finally.

A calf.

Not fat like an adult but perhaps just enough

To keep starvation at bay.

Hunting beluga whales might make the difference between

Life and death for these bears.

But if the ice-free season gets longer.

Even this may not be enough.

Polar animals have evolved to survive the coldest,

Harshest conditions on earth.

But now the polar regions are warming more rapidly

Than anywhere else.

This means new opportunities for some,

But for the most cold adapted,

There are seriously challenging days ahead.

The question is, can they find new ways to adapt

To a fast changing world.

The emperor penguin parents are on the home stretch.

Together they have traveled thousands of miles

Keeping their chicks fed.

(calling).

He hatched out at under a pound,

Now he's over 20, almost as big as his parents.

(calling).

Soon they'll stop returning with food,

Chicks will be catching their own.

(chirping).

(chattering, calling).

This family have done everything they can,

In the hope that their chick will one day return.

And the incredible story of life at the poles

Will continue.

Captioned by cotter captioning services.