Original subtitles

The most powerful predators to walk the Earth.

But it takes more than brute force…

…to reach the top.

With remarkable brain power,

and by making the most of any opportunity,

bears rule some of the planet's most hostile lands.

But cubs aren't born with the skills to survive.

They need to be taught.

So a mother bear has her work cut out

preparing her cubs

to face the world.

Locked in winter's icy grip,

northern forests

are still.

Silent.

No clues to suggest

that hidden beneath the snow,

a giant lies asleep.

Breathing slow.

Heart beating just eight times a minute.

Nothing to eat since fall.

For three months,

this American black bear has been in suspended animation.

Even more miraculous…

three weeks ago,

she woke just long enough to give birth

to three cubs.

Each just the weight of a can of soup.

Though she's surviving on nothing but fat reserves,

her babies won't go hungry.

Her milk so rich,

they've already doubled in size.

This same story is unfolding across North America.

Over half a million hibernating black bears.

Underground.

Or tucked under fallen trees.

Some, incredibly, right out in the open.

Cubs snuggle close, kept alive by their mother's warmth.

But this mom

picked the coziest of dens.

When the spring finally arrives,

her hard work will begin.

A bear's upbringing

shapes the whole of its life.

There are just eight species of bear.

Found from the jungles of Asia

to the ice sheets of the Arctic.

Some are surprisingly small,

just the size of a dog.

Others weigh in at nearly a ton.

Though all are classified as carnivores,

most eat whatever they can get their paws on.

But how to find the right food at the right time

can only be taught by a devoted mother.

Each bear's home comes with its own challenges.

So learning to use brains

as well as brawn

is crucial to survival.

The Arctic winter.

Hostile.

Lifeless.

Well,

not entirely.

Even at 40 below,

a polar bear is well insulated,

with a double layer of fur

and a blanket of fat as thick as a man's arm.

Polar bears never have to hibernate.

Winter is their hunting season.

Seals are their favorite prey,

and polar bears use their astounding sense of smell

to detect them many miles away.

This male has picked up a scent,

but it's not prey.

It's other bears.

Male bears are known to kill cubs that are not their own.

This mom's young, near fully grown, are not so vulnerable.

Still, best to keep their distance.

Before they can strike out alone,

they need to perfect their hunting skills.

And this may be a chance

for Mom to show how it's done.

Approach from downwind.

Use camouflage.

Sneak into striking range.

With each successful hunt,

Mom helps her cubs grow stronger and wiser.

Once they leave her, these lessons will make the difference

between life and death.

Bears start learning from Mom the day they leave the den.

Spring has finally arrived for the black bear family,

and the great outdoors is calling.

Mama bear has lost over 100 pounds of fat since fall,

nearly half her body weight,

so she's ready to get going.

But happily full of milk,

her cubs seem in less of a hurry.

It's a whole new world.

Climbing comes naturally.

Even so, it's a bit of an obstacle course.

Right from the first hurdle…

Mom's got their back.

She alone is provider, teacher, and protector.

It's a huge responsibility.

Around a third of cubs don't survive their first year.

One of the greatest dangers they'll face

is other bears.

Brown bears, sometimes known as grizzlies,

have come down from winter dens in the mountains.

They gather in coastal meadows to feed on sedge grass.

Bears don't defend a territory like cats or dogs,

but they still know who's boss.

This old dominant male

has laid claim to this grazing spot for years.

He needs to pile on the pounds

so he can take on anyone who dares challenge him

when breeding season arrives.

This grass is surprisingly high in muscle-building protein.

But if you're smarter than the average bear,

there's even more nutritious food to be found.

This mom is taking her cub

on an exclusive dining experience.

A muddy beach might look unpromising…

…but a little digging can unearth some treasure.

Once you've found a clam,

it needs shucking.

A surprisingly delicate operation.

Not all bears here can do this.

She picked it up from her mother.

And now she's passing it on.

At low tide,

a talented clammer might get a hundred of these juicy treats.

A much better protein hit

than from the same time spent grazing.

Teaching her daughter will give her a head start in a competitive world.

A stranger.

Time to back off.

Another important lesson.

Avoid confrontation if you can.

An angry bear is a force of nature.

Even when the opponent is bigger,

never bet against a bear.

Or its claws.

Up to four inches long, they're fearsome weapons.

But they're also multi-purpose tools.

Climbing spikes.

Shovels.

Ice hooks.

Even silverware.

And when it's time for a good old scratch…

…there's nothing better.

Some of the longest claws

belong to the smallest of bears.

Just one-tenth the size of a grizzly,

a sun bear is a jungle survival specialist.

Finding food in the tangle of vegetation

isn't easy.

But with an almost unrivaled sense of smell…

he follows his nose.

He's narrowed down the source of the sweet aroma.

Just one problem.

It's all the way up there.

Four stories high.

But sun bears

love honey.

Good thing they're also champion climbers.

Those long, curved claws give excellent grip,

and a dog-sized frame keeps him light and agile.

But

he's barking up the wrong tree.

And now

he's got competition.

Or has he?

Sun bears also love feasting on grubs inside rotten logs.

While the other bear's distracted,

a chance to switch trees.

The bees are angry,

but thankfully stingless.

At last…

he's struck gold.

Those claws also make a handy honey scoop.

And a ten-inch tongue does the rest.

When it comes to finding food in the jungle,

sun bears have it licked.

But as the forests they rely on are cleared for agriculture…

it's leaving sun bears homeless.

And more exposed to poaching for traditional remedies.

They're now the rarest bear on Earth.

Rarer even

than the most enigmatic bear of all.

The giant panda spends most of its life

eating just one thing.

Bamboo.

She can lounge around for 12 hours

gorging on the stuff.

It makes up 99% of her diet.

She's the only bear

with a bony pad on her paw, kind of like a thumb.

Perfect for making a bamboo hot dog.

This veggie diet seems a bizarre choice.

Pandas evolved to eat meat.

But because bamboo's plentiful

and grows year round,

over millions of years, they switched to the easier option.

Trouble is,

their gut hasn't fully adapted to digest it.

So she only survives by doing a lot of eating.

And very little else.

But when humans cut down swathes of Asia's bamboo forests,

pandas had nothing left to eat

and were forced to the brink of extinction.

Such a specialized diet is the exception.

Most bears have more adventurous tastes.

The forests on the Canadian border

are home to tens of thousands of black bears.

It's midsummer, and this mother is leading her cubs

on a feeding foray.

She keeps them on track with soft grunts.

At six months, they're curious.

But still naive.

Mom must be their eyes and ears.

Her low moan tells them

something's not right.

A male.

He could kill her cubs

and force her back into heat.

When Mom growls, it's time to hide.

She's warning the male,

but he's not getting the message.

That cough means "climb."

Now Mom must keep her nerve and stand her ground.

Until he understands

she's not to be messed with.

Ever since leaving the den,

Mom's encouraged her cubs to climb.

It's paid off.

Till she's sure the coast is clear,

they'll stay off the ground.

A chance for some more climbing practice,

while Mom grabs a bit of well-earned shut-eye.

But not too much.

Fall is coming,

and the whole family needs to feed up.

In more hostile lands,

finding food and water

is a year-round struggle.

These peaks may look uninhabitable…

but for a few spectacled bears,

it's home.

The only species of bear in South America.

The real-life Paddington.

But no need for a duffle coat and rain hat here.

The tallest mountains block clouds…

…creating a high-altitude desert.

It can go eight months without rain.

This is the only natural spring for miles.

A lush oasis.

He could chill out here all day.

When a male hogs the bath,

others must be more resourceful.

This mother is showing her cub

how even a tree trunk

can be a survival aid.

With the strongest jaws for her size of any bear,

she easily tears it apart to reach the moisture inside.

Food and water are so scarce,

she must save energy.

Rest often.

It's a lot cooler off the ground,

but spindly trees don't offer much support.

So she does something no other bears do.

She makes her own bed.

It's this ingenuity

that helps see her through till the rains finally return.

Naturally air-conditioned.

Nice and comfy.

The perfect spot for a siesta.

In the far north,

life is less peaceful.

The dominant grizzly.

Since spring,

he's packed on two pounds a day.

He needs the extra weight.

It's being bigger and badder that makes him the boss,

controlling the best feeding spots

and mating with the local females.

But after a decade in charge,

he seems to be losing his charm.

And a bigger problem is coming his way.

A younger male has sensed weakness.

The boss needs to prove himself to the females

and show junior who's in charge around here.

The cowboy swagger.

It's meant to look imposing.

The only thing is,

the youngster is enormous.

But with females watching on…

…no backing out now.

The old boss is down for the count.

The meadow's getting a change in management.

Effective immediately.

The old boss's reign is over.

The female made the smart choice,

holding out for a stronger, fitter bear to father her cubs.

He spends the long, warm days

reaping the rewards.

But even further north,

just getting through the summer

is a serious struggle.

Each year, as the Arctic warms,

the sea ice retreats north.

Polar bears become stranded on land, where there's little to eat.

And now that climate change is making the ice melt earlier,

polar bears go hungry for longer.

A mom must do what it takes

to keep her family alive.

Even if it means leading them towards danger.

On the north Alaskan coast,

subsistence whale hunters leave piles of bones.

Driven by hunger,

bears come together to scavenge.

They tolerate each other… to a point.

Mom knows her cubs are vulnerable among bad-tempered adults.

But the threat of starvation is even worse.

The cubs will have to learn to cope with uncomfortable situations like this

if they're to survive longer, hotter summers ahead.

Even so, polar bear numbers are predicted to fall by a third

over the next few decades.

They're not the only ones under threat.

Six of the eight bear species are vulnerable to extinction.

Their biggest threat

is habitat loss.

Many also face persecution.

But it's not too late to save them,

to protect the wilderness they need to thrive…

and help bears by rescuing,

rehabilitating,

and releasing them.

It's been shown to work.

Breeding projects and forest protection

have almost doubled the number of wild pandas.

If we make room for bears,

their adaptable nature will do the rest.

As long as they have someone to show them the way.

As fall colors sweep across North America…

black bear mothers have one last push to get cubs ready for winter.

They target foods high in calories.

In a good year, the acorn harvest provides plenty of carbs and fat.

But when there's not enough food in the wild,

bears get their dinner to go…

heading downtown

to make the most of the food we throw away.

In the urban jungle

or out in the wild,

bears rely on their resourceful nature to feed up through fall.

And the bigger the bear, the more epic the feast.

Brown bears,

the most widespread of all bears,

found across North America, Europe, and Asia.

The largest live where there's plenty of food.

And there are around 10,000 on this volcanic peninsula.

But this land will soon be snowbound for six months.

To survive a hibernation that long, they'll need to double their weight.

And there's only one way to do it.

Go fishing.

Every year,

millions of breeding salmon provide a bonanza of prey.

A big male can gorge on a staggering 100,000 calories a day.

That's 300 cheeseburgers.

It's called hyperphagia.

They can eat

and eat

and eat

without ever feeling full.

Taking a seasonal feast and storing it as fat,

fuel for the long winter ahead.

Each bear lives life a little differently.

But there's something they all have in common.

The time mothers spend

passing skills down generations…

…and leading their cubs through the seasons

is the real secret to a bear's success…

whether enduring harsh deserts

or heading out once again to face the Arctic winter.

The black bear cubs have made it to the end of their year.

Back in the den,

batteries fully charged…

…they've gone into standby mode.

Safe and warm,

they'll sleep tight till spring returns.

Snuggled up to Mom.