All language subtitles for PBS.Nature.Snowbound.Animals.of.Winter.720p.HDTV.x264.AAC.MVGroup.org.eng

♪♪

BUCHANAN: I'm Gordon Buchanan,
a wildlife cameraman.

I've filmed in some
of the planet's

most extreme
and bitterly cold places.

Despite being so harsh,

these frozen wonderlands
are full of life,

with creatures that
somehow manage to survive

against all the odds.

I'll be meeting some
of these fearless animals,

from sociable wolves

to the enigmatic lynx

and cunning Arctic foxes.

That is the most sumptuous
animal I've ever seen.

These are creatures
that are specially adapted

and have evolved to live
in the snowiest,

coldest places on Earth.

How they're able to survive

the big freeze is extraordinary.

♪♪

♪♪

[ Wolves howling ]

BUCHANAN: I'm in the Arctic.

It is incredibly beautiful,

but it is also incredibly cold.

Winter temperatures here
can drop to

as low as minus-50 degrees.

Yet for some creatures,

like these magnificent wolves,

they call this place home.

They live on top of the world

in one of
the earth's freezers...

the Arctic Circle.

I'm in Polar Park in Norway,

the most northerly wildlife park
in the world.

The wolves here have grown up
with humans around,

so they're used to people.

But I still need
to gain their trust

and have to remain
quiet and calm.

Despite the cold, I've had
to take hat and gloves off

or these guys
would be too tempted

to snatch them off.

Hello.

[ Wolf whines ]

This magnificent beast
is treating me

like another wolf
and saying hello.

That's how they
greet each other --

with their mouths.

Wolves often nibble
on each other's faces.

It might look aggressive,

but it's a sign of affection.

The size of the paws.

You are a beaut!

Just stroking this wolf,

you can lose hand in its coat.

And when I part the hair,
you can see the underneath,

these fine, very soft hairs
that gives insulation,

and these longer, outer hairs

repel the snow and water.

His coat is perfect
for these conditions.

But like the domestic dog,

the foot pads, the toe pads
of the wolf

are completely naked.

And they spend
most of their lives

with those naked toe pads
and foot pads

in contact with the snow and ice
certainly in the winter.

So how do the wolves stop
that cold temperature

coming from the ground
up through their naked feet

into the rest of their body?

Well, they've got a very, very
clever solution to that.

Hot blood never
reaches a wolf's paws.

As it flows down the leg,
it's cooled down --

almost like entering a fridge.

Only cold blood
is kept within the paws

so that all the warm blood
can remain within the body.

This clever adaptation
means that any heat loss

is kept to an absolute minimum.

On a thermal camera,
which shows body heat,

the upper part of
the wolf's legs are red,

showing them to be warmer
than its feet.

The wolf's coat looks blue.

That's because
his stunning thick fur

is preventing
heat loss from his body.

So no matter what physical
characteristics you have,

a clever hunting strategy
is essential.

And in these bitterly cold
conditions,

it helps to have friends.

A wolf's ability to hunt
as a team, as a pack --

that's really what helps
guarantee its survival.

Being part of
a strongly bonded pack

is invaluable in the coldest
part of winter.

[ Wolf howling ]

In North America,
this pack have been

waiting until their prey
is at their most vulnerable.

[ Elk bugles ]

The elk here are
weak with hunger

and in such deep snow,
they struggle to run very fast.

[ Elk bugles ]

The wolves follow
a well-practiced formula.

They target a straggler
of the group.

Three members of the pack work
together to bring the elk down.

It's a brutal but impressive
hunting strategy.

Impeccable teamwork, along
with remarkable adaptations,

make wolves stand out
as supreme snow animals.

Not all snow animals live
in social groups like wolves.

In fact, one of the most
successful snow animals

is solitary

and lives most of his life
alone.

They can be found
in the very far

north of the Arctic --

the polar bear.

This male,
like every polar bear,

is almost completely
covered in fur.

But his secret to staying warm
in this frozen land

is actually inside
his large body.

He has a huge layer
of insulating fat --

about four inches thick.

It traps heat, keeping him
warm from the inside.

To maintain this fat, he relies
on his good hunting skills.

His prey is hidden
under the thick ice.

Luckily he has a secret
weapon to help him hunt --

an extraordinary sense of smell,

a hundred times
stronger than ours.

♪♪

He can detect a seal carcass

from around 20 miles away,

and under three foot of snow.

Success.

He will eat all the fat
of a seal first,

often leaving the actual meat.

This extreme fatty diet
would kill us,

but for the polar bear,
it's essential.

Indeed, they are one of
the fattest mammals on Earth.

Their incredible insulation
and intense sensnse e e of l

make the polar bear
a master in the snow.

They're also built
to move around

effortlessly in this
snowy environment,

unlike me.

I am a perfect example
of an animal

that is not adapted
for walking about

a snowy environment like this.

I'm 12 stone,
12 and a half stone,

and all of my weight
is distributed

onto my feet -- size 12 --
big feet for a human,

but not big enough to stop me

from sinking down into the snow.

What I need to do is increase
that surface area --

put on some snowshoes.

I suppose the secret to
moving around in deep snow

is to do it efficiently.

Here we go --

adapted for walking
in the snow.

That is so much better.

It's easy.
I can walk through the forest.

I'm not sinking down in
to my waist.

I can go fast.

I can almost go silently.

Like I belong here.

Polar bears have built-in
snowshoes.

Their paws are wide, measuring
up to 12 inches across.

This helps them to distribute

their weight evenly on thin ice.

Underneath their large paws
are small, soft bumps

to give them extra grip
on the ice.

As well as being superbly
adapted to the snow,

some bears have another strategy
to get through winter --

by sleeping through it.

This is the recently vacated den
of a brown bear.

The den would have been dug
back in the autumn,

'round about October time.

In the hardest of winters,

a brown bear will spend up
to seven months in its den,

not eating, not drinking,

just drifting in
and out of sleep,

waiting for the thaw.

A bear will make a den

which is just slightly bigger
than itself --

a snug fit.

Some dens are built in
rock crevices or hollow trees.

For others,
like this polar bear,

it can be simply a case
of digging a small hole

and then
waiting for the snow to fall,

providing an excellent,
insulating roof.

♪♪

This female polar bear,
filmed in captivity,

is in hibernation.

During this time, her heart rate
drops dramatically

and she doesn't eat,
drink, or urinate.

Amazingly,
she's able to recycle waste

into new protein

to maintain her muscles.

Although she survives
purely on fat reserves,

she can, remarkably,
give birth in hibernation.

Her body heat
keeps her babies warm.

They grow rapidly thanks
to her extremely fatty milk,

which is nearly 10 times
richer than human milk.

♪♪

I've spent much time
filming polar bears

and been lucky enough
to see tiny twin cubs emerge

from their winter den --

a truly wonderful sight.

Aww.

Aww, very, very cute.

They were very eager

to explore the big, wide world.

After being born in hibernation,

the family venture out when
the babies are strong enough

to survive outside

and ready to make the trek
to the spring sea ice.

Oh, wow.

Look at that.

It's a sight
I will never forget.

Many smaller mammals
also hibernate

to avoid the bitter winter,

but there is one which does so
with a unique twist --

the Arctic ground squirrel.

When the harsh weather begins,

the ground squirrel
escapes to an underground burrow

to hibernate.

Amazingly,
the squirrel's body temperature

drops to below freezing --

the lowest of any mammal.

His major organs shut down,

and he looks dead to the world.

Despite this, he's able
to stop himself

from actually freezing to death.

Every few weeks,
the squirrel begins to shake.

This shivering is enough
to raise his body temperature

back to up normal
for a few hours.

After this session of shivering,

he can safely cool back down,

ready for another cycle
of deep sleep.

For animals that
don't hibernate,

being well-insulated to

withstand severe weather
is essential.

For human beings in the cold,
we have to layer up.

I've got five layers on.
I've got gloves on.

We generate heat,
and we want to retain

that heat in
sub-zero temperatures.

And if I remove my glove,
it goes without saying

my hands start losing heat,

my hands start feeling cold,

and you can see the comparison

very clearly
on the thermal camera

between my cold hand
and my warm hand.

The fingers on my cold hand
are blue,

showing how much heat
they've already lost.

Animals are far more efficient
than us at retaining heat.

And there is one animal
which tops the lot.

The Arctic fox is superbly
kitted out for the winter.

To prepare for it,

he undergoes
a spectacular transformation.

His thin brown summer coat

changes into one
which is 200% thicker.

It's white,
and it's very, very fluffy.

Hello, you handsome,
handsome boy.

My word.

That is the most sumptuous coat

I have ever seen on any animal.

In fact, Arctic foxes

have the warmest coat
of all Arctic mammals.

And it's not just that fabulous

fur the fox has got.

They have incredible senses --

particularly the hearing.

And despite having
these fairly small ears,

this fox will be able
to detect his prey

with pinpoint accuracy

even when it's hidden
underneath the snow.

In the depths of
the Canadian winter,

a young Arctic fox
is searching for food.

He's still a hunting novice.

It's not easy when
you can't see your prey.

With his acute senses,

he can hear a faint sound
under the snow.

[ Chirping ]

Lemmings.

To catch one,

he uses a special pouncing
technique

known as mousing.

He has to judge
its exact distance

as well as the depth
of the snow.

To help them find
the right spot,

foxes actually
align their pounce

to the Earth's
magnetic field --

an extraordinary skill.

[ High-pitched chirping ]

But mousing isn't always easy,

especially for a beginner.

♪♪

Super senses are
crucial for animals

that live in such white
and snowy landscapes.

And I'm about to meet one
whose eyesight is legendary.

This exquisite-looking cat
is a lynx.

It's a cat that is especially
adapted to the snow.

Look at those eyes.

Lynx have incredible vision.

It was once believed that lynx
can see through walls.

And actually looking
into those eyes,

I find that quite easy
to believe.

Maybe that's stretching it
a bit,

but a lynx can spot a mouse
from 80 yards away.

And their night vision
is truly remarkable,

far better than ours.

At this time of year,

when the landscape
is dominated in snow,

you can see how easily the lynx
just disappears in it --

matches these birch trees.

It's almost invisible.

That's all the lynx needs

is a little bit of something
to break up its outline.

In the wild, lynx are
incredibly difficult to glimpse.

They roam the remote forests

for hundreds of miles
in search of prey

and may never visit
the same patch twice.

With so few prey animals here,

life for this silent hunter

is particularly hard.

And in this harsh wilderness,

they're not the only hunters.

The great gray owl
waits and listens.

He's watching for prey.

He has excellent,
super-sensitive hearing.

He can even hear the scuttling
of voles or mice

beneath two foot of snow.

He glides silently, like
a king of acoustic stealth.

His wings absorb
any noise of flapping

so he can take his prey
by complete surprise.

[ Mouse squeaks ]

To survive in a snowy landscape,

it helps to have
a secret advantage,

a trump card up your sleeve.

My next snow animal has
quite a surprising one.

Reindeer traditionally
pull sleighs

and have a popular reputation
for red, glowing noses.

But behind this folklore,

there is
some surprising truth --

an ingenious adaptation

which helps them
survive the extremes.

Their noses are full
of blood vessels.

These cool warm air down
as it leaves the body

and warms cold air up
as it comes in,

keeping the reindeer's brain
constantly warm and active.

So, as the thermal
camera proves,

reindeers' noses
are actually red.

It's not just the nose
of the reindeer

which is extraordinary.

How they view
their winter surroundings,

through those large,
characterful eyes,

is truly astonishing.

When it's bright and sunny
like this,

my eyes struggle to cope with
the amount of UV light

that's coming from the sun

and is bouncing
back up off the snow.

If I was to spend too long here,

I'd eventually damage my eyes.

I could become snow blind.

But reindeer,

they see things differently.

Not only can they see
in color like I can,

they can also see
in ultraviolet.

For us, it's difficult
to make out detail

when the landscape is so white.

But with UV vision,

a reindeer can see things
in much greater contrast.

They can see shapes
and detail that we can't.

The lichen on the trees
which they eat

or animal urine in the snow
becomes more prominent.

In such a white, snowy world,
it certainly helps

to have that extra insight.

Reindeer even have specially
designed, flexible hooves.

In the winter, their four toes

can spread out wide
to act like snowshoes.

This means they can
walk on bumpy ice

without slipping.

However, on smooth ice
they can sometimes

find their shoes
a little ill-suited.

♪♪

When it comes to surviving
against all the odds,

there is one snow animal

which has to endure one

of the most
extreme places on Earth.

From the top of the world
to the very bottom

is Antarctica,

the coldest, windiest, and
driest continent on the planet.

This desolate freezer is also
the chosen home of the penguin.

[ Penguins calling ]

How do they survive in
minus-90 degrees Fahrenheit?

Well, penguins
are superbly built

to resist the extreme cold.

First of all,

their round, shapely figure
isn't by accident.

It provides them with
enough blubber to keep warm.

But how do penguins
manage to keep

their extremities
like wings and feet warm?

Well, their bodies
are cleverly adapted

so that the muscles needed
to move their feet

and wings are kept inside
their warm, round body.

Only tendons operate
within the actual limbs,

and these are far less
vulnerable to the cold.

But it doesn't stop there.

These ice specialists

have another clever trick
to keep warm.

To reduce the amount of body

touching the frozen ground,

they just lean back
on their heels,

picking their toes off the ice.

It can decrease their
heat loss by 15%.

Penguins may not be able to fly,

but they do have
a lot of feathers.

And it's thought that penguins
have more insulating feathers

than any other bird.

And I've got some here.

Just look at them.

These are from
an emperor penguin,

a species that has to endure

bitterly cold
Antarctic conditions.

And it is a masterpiece.

At the base, it's incredibly
downy and fluffy.

The quill part is stiff.

The end is slick.

This is the waterproof part.

And on the bird,
these feathers interlock.

The outside is waterproof.

It creates a waterproof seal.

Underneath is an air void
full of these downy feathers.

This is an incredibly

sophisticated form
of insulation.

Penguins are understandably
very protective

of their precious feathers.

So much so, that when
the males come together

to form their famous huddle,

they take extra-special care
not to damage them.

In the deepest part
of the Antarctic winter,

the male emperor penguins

are huddling together
to try and keep themselves,

and their eggs, warm.

The center of the huddle
is the hottest part.

It can even get too hot.

So the penguins
constantly move around,

changing their position.

But instead of pressing
into one another,

they are barely touching.

If they were squashed together,

the insulation from
their incredible feathers

would be compromised.

So they leave
almost an inch gap

between each other
to protect their feathers.

This means that
if one penguin moves,

its neighbor has to react
and follow suit.

Just one penguin's step
creates a chain reaction,

sending a ripple of movement
throughout the huddle.

There is only one mammal
which is tough enough

to live this far south

in the Antarctic all year-round,

and that's the Weddell seal.

This incredible snow animal
spends much of its life

under the expanse
of the frozen sea ice.

The Antarctic Ocean can drop
to 28 degrees.

Weddell seals can only survive

about an hour under
the freezing water

before needing air.

They have to find
a natural crack in the ice

to create a breathing hole.

To do this, they have
a unique adaptation.

A sharp tool designed
especially for the job --

large, very strong,
protruding teeth.

With these razor-sharp incisors,

a seal is able
to scrape away fresh ice

and keep the hole open.

♪♪

But these breathing holes
also serve another function.

The males attract females
to them

during the mating season.

One male can draw
up to 10 females,

so the holes
are hotly contested.

This Weddell seal male
is on the search for one.

It's not easy in the gloom
under the ice,

but it's thought
that seals may use

their acute hearing

and sense of touch through
their whiskers to help them.

His call can be heard

by other seals
nearly two miles away.

[ Seal calling ]

He's found a hole,

but another male
has beaten him to it.

Let battle commence.

The occupant is just
too strong for him.

For now,
he'll just have to move on

and hope his luck
will improve elsewhere.

♪♪

In the far northern
coast waters,

most birds have migrated
for the winter.

But one species of bird
braves the icy seas --

eider ducks.

Hundreds of thousands of them.

This patch of water
is their last refuge.

These open pools
are kept free of ice

by strong currents underneath.

From here, the birds can
dive down into the water,

picking off mussels
from the depths of the sea.

Surrounded by ice,
the eiders' survival

depends on this single,
vulnerable oasis,

and conditions here
can change very fast.

In a smaller pool,

other eider ducks
are learning a bitter lesson.

An early winter storm
has caught them out,

and the ice is closing in.

The pool is shrinking,
and the ducks are perishing.

The larger pool has
a far greater chance

of staying open all winter,
and the ducks

will have avoided
an exhausting migration.

It's always a gamble,
but for these ducks,

one which should pay off.

As the winter progresses,

temperatures plummet

and snow can sometimes fall
for hours at a time.

Snow forms when water vapor

in the atmosphere
freezes into ice crystals.

The ice crystals
become snowflakes

as they fall to the ground,

each one intricate and unique.

Although snow appears white,

it's actually colorless

but reflects the light
from the sun.

Falling snow looks
beautiful to us,

but it can be deadly.

As the snow gets
deeper and deeper,

animals need to be even more
specialized to cope.

When it comes to being prepared

for the coldest part
of the winter,

these musk ox
certainly look ready.

That long, thick, shaggy coat
is so efficient

a musk ox only uses a small
amount of energy to keep warm.

They can even slow
down their metabolism

so that in the wintertime,
they require less food.

And to get to that food,

their front hooves are bigger
than their rear hooves

to dig down through
the deep snow

to get to the food.

And if the snow is
very, very deep,

they can use their big head
and massive neck muscles.

They can excavate the snow
to get right down there

to the vegetation beneath.

Musk ox look like an animal

that has been especially
designed for the cold.

These hairy,
prehistoric-looking creatures

have inhabited the Arctic

for thousands of years.

They roam on the Arctic tundra
in search of roots

and mosses that sustain them.

They live in herds
and can withstand

incredibly harsh Arctic winters.

In the American Rockies,
there's another snow animal

with a very similar
hardy physique -- bison.

Yellowstone is a unique place.

A quirk of geology has created

thousands of thermals
and geysers.

But it's not for the feeble.

For half the year,
Yellowstone is frozen.

Temperatures can reach minus-50,

and the winter snow can be
more than 20 foot deep.

Just as well these bison
are built for the snow.

However, they are struggling

in what is the snowiest
winter here for a decade.

They're able to swing their
massive heads through the snow,

but this year it's so deep

they can't reach
the grass underneath.

A bison's amazing, thick coat

keeps it warm down
to about minus-22.

But the wind chill is now
pushing them to that limit.

They need to move.

That will take more energy.

It's a risk that
they will have to take.

The herd need to find
somewhere warmer to survive.

They follow an ancient route

where hot thermals have
kept the river running.

It should lead to a place
they can eat and rest.

It's a long, hard trek.

The bison have
to keep to moving.

They just can't afford to stop.

In such a tough landscape,
not every bison will survive.

The herd have finally
reached their destination.

It's an oasis.

Thermals have melted the snow,
and grass is abundant.

It's a huge relief.

The bison can fill
their empty stomachs at last.

But not all is rosy in paradise.

Due to the volcanic waters
and geysers,

the grass here
is laced with arsenic

which could, over time,
slowly poison the bison.

The herd know
they can't stay too long.

However for the moment,

it offers them a lifeline
from the unrelenting snow.

♪♪

Food can be incredibly hard to
find in a landscape like this.

The rivers and the lakes
are completely frozen.

The snow underfoot is
incredibly deep.

So animals have to use
every trick in the book,

every ounce of their
intelligence just to stay alive.

A family of otters
is making its way

to a river kept open thanks
to the underwater geysers.

Here, they can happily fish
for a much-needed dinner.

♪♪

However, they are not alone
in this snowy landscape.

They are being spied on
by a clever trickster --

a coyote.

He's been watching and waiting
as the otters dive for fish.

This otter doesn't want
to risk losing his dinner

and plans to hide his catch
under the ice.

Although the coyote
can't see the otter,

he can hear him moving
somewhere underneath him.

The otter emerges
but without the fish.

He's stashed it somewhere
under the ice, but where?

It's turned into a game
of hide-and-seek,

and the coyote fancies
his chances.

♪♪

A huge trout -- what a prize.

In these conditions,
being cunning as well

as a little bit devious
can be the key to survival.

Beneath the blanket of snow

is another game of
hide-and-seek...

...one which is a matter
of life and death.

This little vole is active
throughout the winter.

He travels along tiny corridors,

moving 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 freezing --

warm enough
for the vole to thrive.

But he's not the only one
out here.

A least weasel is also about.

♪♪

He may look cute and friendly,

but he has a devious plan.

His body is exactly
the same width

as the vole's,

so there's nowhere the vole can

go that the weasel can't follow.

The weasel's long, slender shape

is perfect
for hunting in the tunnels,

but the worst possible shape
for staying warm.

So to solve this problem,
he has a solution --

though not a good one
for the vole.

The weasel plucks the fur
from the vole's body

tuft by tuft.

Then, putting it all together,

he cleverly makes
a warm blanket.

A sad end for the vole,

but a warm, underground bed
for the cold-hearted weasel.

It's everyone for themselves
in this climate.

We've seen some
amazing strategies

for surviving the cold.

But there are other creatures
battling to stay alive,

things we don't even see.

Underneath the snow,
they are thousands of insects

having their own battle
with winter.

And bizarrely, for some of them,
their survival strategy

is being frozen alive.

♪♪

One of the most remarkable

is a small Arctic caterpillar

known as a woolly bear.

He spends his winter
curled up under a rock.

As the temperature drops,
he goes into a kind of coma,

his heart stops beating,

and his insides
completely freeze.

He remains frozen like this
for four months.

Then, when the Arctic
spring arrives,

he thaws out,

as if rising from the dead.

This furry little critter eats

as much as he possibly can

before the cold closes in
once again.

♪♪

And so it goes on.

Year after year,
he slows right down

and freezes solid to survive
winter after winter.

The feeding season
in the Arctic is so short,

it can take years
for the caterpillar

to complete its growth.

But eventually that time comes.

The caterpillar
frantically starts to weave

a beautiful silk cocoon.

Meanwhile, inside,
his body starts

to change into one that can fly.

Now, the oldest caterpillar
in the world

is ready to fulfill
his life's purpose.

He has just days to find
a partner and mate

so he can help create
the next generation

of wonderful woolly bears.

He may be tiny and hidden away,
but this little caterpillar

has one of the most
extraordinary ways

to survive the big freeze.

[ Wolves howling ]

We've seen how
some remarkable animals

can adapt to their surroundings.

These are animals
that not only live,

but thrive,
in some of the coldest,

most inhospitable
places on Earth.

Whether it's their super senses,

their extraordinary
physical adaptations.

or whether it's just
clever tactics,

these animals are a thing
of great wonder.

And for me, these animals
are not only the most

impressive creatures
on the planet,

they're some of
the most beautiful.

♪♪

♪♪

♪♪

♪♪

To learn more about what you've
seen on this "Nature" program,

visit pbs.org.

♪♪

♪♪