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The polar winter.

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This is the planet at its most hostile.

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

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The high Arctic in late autumn,

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empty and abandoned to ice and snow.

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Most animals migrated south weeks ago.

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The few that stay
will face violent winds,

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plunging temperatures
and months of darkness.

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A female polar bear
searches for shelter.

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Other bears are out on
the frozen ocean looking for food

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but she won't feed again
until next spring.

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

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The snow here is easy to work.

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It's soft and light,

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a sure sign that soon plenty more
will accumulate on this slope,

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as winter advances.

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And that is what she needs.

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

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Once the snow here is deep enough,

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she will dig down to make a den.

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She'll then lie, waiting for her cubs
to be born as winter sets in.

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

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

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are now locked out.

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But there are windows in this
white desert,

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gateways to the rich ocean below.

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Most birds have migrated south,
but in the frozen Bering Sea,

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ducks of one particular species

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are gathering together
in a single, immense flock.

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Spectacled eiders,
hundreds of thousands of them.

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With the seas that fed them
throughout the summer all but frozen,

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this is the eider's last refuge.

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Such patches of open water,
kept free of ice by strong currents,

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are given a Russian name, polynyas.

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If this polynya stays open all winter,

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the ducks will have avoided
an exhausting migration.

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It's a gamble and a tremendous risk,
especially for the spectacled eider,

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for this polynya
holds the world's entire population.

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Surrounded by ice,

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these spectacled eiders' survival
depends on this single, vulnerable oasis

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and conditions here can change
very fast.

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A smaller pool.

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Here, common eider ducks
are learning a bitter lesson.

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An early winter storm has caught
them out and the ice is closing in.

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The pool is shrinking and
the ducks are freezing to death.

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These gamblers have lost.

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

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the cold pushes south
into Arctic lands.

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Winter brings
a devastatingly destructive force,

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frost.

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Ice crystals form
as moisture in the air freezes.

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

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and their sap.

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With these first frosts,
most plants die,

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their insides ripped apart
by ice crystals.

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Coniferous trees, however,
like fir and pine,

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can withstand very low temperatures.

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

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This is the Taiga.

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

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As winter deepens,

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frigid air from the Arctic meets
warm, moist air from the south,

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producing particularly heavy snows.

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For the big animals of the forest,

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there's no way of hiding
from the winter.

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But size, for the bison of Northern
Canada, is in fact their salvation.

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Big bodies lose
less heat and can carry more insulation.

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

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And only a large predator
can tackle them.

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Wolves hunt better in packs,

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but there are only two of them here
and the prey they pursue are giants.

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A vast Arctic wilderness
stretches all around.

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In it, somewhere, there are bison.

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These deep tracks in the snow
are easy to follow

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but which way were the bison going?

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They have detected a scent,
the hunt is on.

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Running in the bison's tracks is easy.

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The snow here is compressed and firm.

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At this rate, the wolves will
soon catch up.

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They attempt a shortcut.

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The giant bison can plough on
through virgin snow,

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but for the wolves,
deep snow is a hindrance

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and now they're losing ground.

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

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The bison are the only prey
here in winter,

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the wolves have no option,
they must tackle them.

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But bison are 10 times their size!

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

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that for a wolf, even a small
injury could be fatal.

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It's crucial they select
the right target.

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This one is very big.

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Good decision!

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This is smaller, a yearling.

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Even though it's young, it's nonetheless
heavier than both wolves combined

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and it is extremely powerful.

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

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But the female is the more determined,
or more desperate.

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

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This a battle of life and death
for them both.

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The bison has no strength left,

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the battle is over.

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Winter deepens,

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the snow continues to accumulate,
smothering the forest.

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Some trees are loaded
with three tons of snow.

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It shuts out what little light
there is at these latitudes,

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and that shortens
the growing season still further

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and limits how far north
trees are able to grow.

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So snow influences
both the shapes of the trees

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and the extent of this forest.

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And it affects the animals, too.

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It helps to have friends if you want to
find food at this time of the year.

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Wolverines and ravens,
a match made in the Taiga.

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It's the hardest time
of the year to find food.

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But the wolverine knows that a raven's
call is as good as a dinner bell.

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

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The moose carcass is frozen solid,

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but the wolverine has
immensely powerful jaws,

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well able to deal with "frozen food".

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The raven's bill is more suited
to leftovers.

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The raven has to be patient.

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A wolverine's appetite is legendary.

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According to folklore,
it can eat more at one sitting

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than any other creature in the forest,
hence its other name, the glutton.

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What the wolverine can't eat now,
it stores in the deep freeze.

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It will bury these food parcels
across the forest,

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planning ahead for leaner times.

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For a few, the snow is an ally.

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Voles stay active throughout the winter
beneath the snow,

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despite the freezing temperatures above.

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Travelling along tiny corridors,

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they move from pocket to pocket
of perfectly refrigerated food.

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Snow is a great insulator,

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so down here the temperature never falls
more than a degree or so below zero

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and that's warm enough for
a vole to thrive,

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even if it lacks the stature of a bison.

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In some years vole numbers boom,

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and then they are forced break cover
to search for more food.

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The great grey owl is
silent and very skillful hunter,

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but deep snow can be beyond its reach.

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But such snow is no barrier
to one predator.

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The least weasel.

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A tiny hunter and the vole's nemesis.

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Its body is exactly
the same width as a vole's,

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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,

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but the worst possible shape
for staying warm.

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So they need a special
way of doing that.

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

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

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under which to sleep in her den
below the snow.

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Midwinter in the northern forests.

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The sun is so low
that it's twilight at midday.

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Further north in the high Arctic,

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the sun has been below
the horizon for months

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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.

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Few creatures can
endure these conditions.

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

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possibly that of
a fox or another polar bear.

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But otherwise, he must
live on his reserves.

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This is the time to scrape by, to wait.

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

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The cubs are born blind and tiny,

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

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Despite her sleepiness,
her instinct to nurse is overwhelming.

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The cubs' clucking calls stimulate her
to produce milk.

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And what milk!

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It's nine times richer than our own

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and enables her to double their weight
every few weeks.

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It's over two months since
the autumn snows first arrived.

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In two more months, polar bear families
will emerge onto the snowy slopes

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all around the Arctic.

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

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

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After travelling millions of miles
across space,

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solar winds, attracted by
the magnetic pull of the poles,

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collide with the Earth's atmosphere.

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Trillions of charged particles
dance across the sky.

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Above the Arctic, the Aurora Borealis,
the Northern Lights.

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In the south, it's the Aurora Australis,
the Southern Lights,

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that bring light to
Antarctica's long winter.

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These spectacular light shows
are only a tease.

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Solar energy maybe, but no warmth
that will help the emperor penguins.

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The Arctic winter is brutally cold,

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but in Antarctica,
the darkest months are even more savage.

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The male penguins have not eaten
for months

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and have only each other
for protection from the gales.

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Each has been entrusted
with a single precious egg,

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balanced on top of its feet.

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If the egg were to drop onto the ice,

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even for a moment,
the chick inside would die

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and all this would count for nothing.

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00:28:56,080 --> 00:28:58,880
The emperors are not entirely alone.

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The Weddell seal,

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the only mammal to remain here
throughout the winter.

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00:29:15,640 --> 00:29:17,720
They must have breathing holes,

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00:29:17,840 --> 00:29:21,880
and so have to constantly scrape away
the ice that threatens to close them,

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

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00:29:31,800 --> 00:29:36,320
Beneath the ice, they are beyond
the reach of the bitter winter winds.

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00:29:40,400 --> 00:29:43,520
The sea is -2 degrees centigrade,

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a warm bath compared to
the conditions overhead.

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00:29:59,400 --> 00:30:04,480
The roof of ice insulates this world
from the wild fluctuations above.

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00:30:06,400 --> 00:30:11,640
The temperature down here has
barely changed for 25 million years.

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Of course, animals must still be hardy.

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00:30:23,720 --> 00:30:27,880
These Borchgrevinki fish
have anti-freeze in their blood,

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00:30:28,000 --> 00:30:31,320
so they are untroubled swimming
among the ice crystals.

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00:30:36,960 --> 00:30:40,040
Many animals here
are remarkably long-lived,

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perhaps because
the conditions are so stable.

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00:30:43,800 --> 00:30:46,720
Some sponges could be
a thousand years old

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and large enough for a human to hide in.

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There could hardly be a greater contrast

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00:30:53,640 --> 00:30:57,200
to the bleak, windswept
world just above.

213
00:31:30,480 --> 00:31:33,600
But there is a constant danger here.

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00:31:39,480 --> 00:31:43,120
Swirling patterns in the water
reveal its presence.

215
00:31:44,760 --> 00:31:49,160
They are made by brine,
super-concentrated salt water.

216
00:31:50,480 --> 00:31:51,440
It's a warning.

217
00:31:56,400 --> 00:31:58,240
New sea-ice forming above

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00:31:58,360 --> 00:32:02,920
leaves behind brine that is so
extremely salty it sinks rapidly.

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00:32:08,920 --> 00:32:12,840
As it descends, the sea water around it
freezes instantly

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and forms a sheath of ice,

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00:32:15,280 --> 00:32:19,160
a brinicle that grows downwards
towards the sea floor.

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Winter is reaching down
from the cold world above.

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

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by encasing it in a tomb of ice.

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00:33:21,320 --> 00:33:23,920
Even in the relative warmth
of the water,

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00:33:24,040 --> 00:33:28,280
the lethal cold of
winter threatens life on the sea floor.

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00:33:38,680 --> 00:33:42,760
Another more constant
attack rises from below.

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00:33:43,880 --> 00:33:46,120
Pressure in the depths
keeps water liquid

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even though its temperature
is far from freezing.

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00:33:52,240 --> 00:33:56,200
Currents bring up this colder water
and it turns to ice,

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00:33:56,320 --> 00:33:59,440
covering everything that
can't move away from it.

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00:34:21,600 --> 00:34:26,480
And then the ice, being lighter
than water, begins to float,

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00:34:27,160 --> 00:34:29,520
lifting away anything attached.

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00:34:50,080 --> 00:34:53,280
Even some of the faster-moving animals
are caught.

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00:35:09,160 --> 00:35:12,400
So the ice cleanses the sea floor

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00:35:12,520 --> 00:35:16,960
and strews the ceiling above
with remnants of life from below.

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00:35:28,160 --> 00:35:31,480
A sign that winter is nearly over.

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00:35:34,080 --> 00:35:39,120
The songs of male Weddell seals,
challenging their rivals to battle.

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00:35:45,880 --> 00:35:49,680
The male seal's calls
can heard over 15 miles away.

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00:36:01,480 --> 00:36:04,520
He aims to control
the best breathing holes,

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00:36:04,640 --> 00:36:07,720
for they will determine
his mating rights in spring.

242
00:36:15,480 --> 00:36:19,120
His calls create powerful shockwaves
in the water.

243
00:36:19,960 --> 00:36:21,240
They are threats.

244
00:36:32,440 --> 00:36:34,680
This hole has already been claimed

245
00:36:34,800 --> 00:36:37,400
and the owner will not
surrender it willingly.

246
00:36:47,760 --> 00:36:49,640
No change this time.

247
00:36:50,360 --> 00:36:53,960
The challenger will need to
find a hole with a weaker owner.

248
00:37:02,160 --> 00:37:05,840
The battles continue
until the females arrive,

249
00:37:05,960 --> 00:37:08,800
and that time is now close.

250
00:37:35,400 --> 00:37:38,200
The sun returns to Antarctica.

251
00:37:41,120 --> 00:37:46,120
The longest night on earth has ended
and winter begins to give way to spring.

252
00:38:16,840 --> 00:38:18,880
Female emperor penguins.

253
00:38:19,000 --> 00:38:23,720
After four months feeding at sea,
they are returning sleek and fat.

254
00:38:55,000 --> 00:38:58,480
Penguins, it seems, can fly after all.

255
00:39:01,000 --> 00:39:04,360
But a winter at sea
has left them a little out of practice.

256
00:39:57,160 --> 00:40:01,840
There is no time to waste.
Far away, the males are waiting.

257
00:40:12,640 --> 00:40:15,920
While the females were gone,
the sea-ice grew

258
00:40:16,080 --> 00:40:19,640
and it's now twice the distance
from its edge back to their colony.

259
00:40:27,400 --> 00:40:31,880
Seventy miles away, the males are
in desperate need of help.

260
00:40:34,800 --> 00:40:37,800
Despite doing all they can
to conserve their energy,

261
00:40:37,920 --> 00:40:41,080
many are close to dying from starvation.

262
00:41:32,440 --> 00:41:35,680
Reunited after three months apart.

263
00:41:46,680 --> 00:41:50,920
The reward for her return,
a first glimpse of her chick.

264
00:41:57,280 --> 00:42:00,680
The reunion made,
it's time for the hand-over.

265
00:42:05,800 --> 00:42:09,160
The father finds it hard to let go.

266
00:42:12,160 --> 00:42:14,800
Some gentle persuasion is needed.

267
00:42:17,280 --> 00:42:20,560
He has endured the most appalling
conditions on Earth

268
00:42:20,640 --> 00:42:24,800
to ensure the survival of his chick
and the bond is strong.

269
00:42:27,400 --> 00:42:28,960
The exchange must be quick,

270
00:42:29,080 --> 00:42:33,560
as the tiny chick, unprotected,
could freeze to death in seconds.

271
00:42:45,040 --> 00:42:48,920
A task that began in autumn
has been completed.

272
00:42:49,040 --> 00:42:51,200
Despite the huge odds against it,

273
00:42:51,320 --> 00:42:53,840
the precious chick has survived
the winter

274
00:42:53,960 --> 00:42:57,600
and is now with its mother,
and she has food.

275
00:43:08,000 --> 00:43:10,160
The chick's first fresh meal.

276
00:43:12,400 --> 00:43:14,120
Her mission is complete.

277
00:43:18,160 --> 00:43:22,760
But for other mothers,
the journey ends in disappointment.

278
00:43:25,640 --> 00:43:28,120
Their chicks have not survived.

279
00:43:32,520 --> 00:43:35,840
The female's need to nurture
remains strong.

280
00:43:35,960 --> 00:43:40,600
Any chick that strays from its parent
is at grave risk of being kidnapped.

281
00:44:17,960 --> 00:44:21,760
The chaos may be a consequence
of frustrated parental urge,

282
00:44:21,920 --> 00:44:24,000
but the outcome can be tragic.

283
00:44:41,600 --> 00:44:46,960
For those emperor penguins that survive,
the worst is over for this year.

284
00:44:52,400 --> 00:44:55,440
There will soon be abundant food
for everyone.

285
00:45:05,080 --> 00:45:08,680
The emperors have taken on
the polar winter and won.

286
00:45:09,640 --> 00:45:11,560
The gamble has paid off.

287
00:45:13,120 --> 00:45:15,040
All other animals escaped,

288
00:45:15,160 --> 00:45:17,680
only they remained to raise their young,

289
00:45:18,520 --> 00:45:23,600
and now it is they who will benefit most
from the rich southern spring.

290
00:45:32,520 --> 00:45:36,440
Another arrival is the certain
confirmation that spring is here.

291
00:45:37,360 --> 00:45:38,520
The Adélies,

292
00:45:38,640 --> 00:45:41,760
having spent winter at sea,
have come back,

293
00:45:41,880 --> 00:45:45,880
but they have not even
mated yet, let alone laid their eggs.

294
00:45:54,120 --> 00:45:56,600
Now at last, the male emperors

295
00:45:56,720 --> 00:45:59,080
can return to
where they are most at home.

296
00:46:15,360 --> 00:46:18,680
One season ends and another begins.

297
00:46:20,080 --> 00:46:23,240
The penguins will soon be joined
by migrants

298
00:46:23,360 --> 00:46:27,840
and the far south will bustle with life
for a few frantic months.

299
00:46:38,200 --> 00:46:42,560
But there are only a special few,
north and south,

300
00:46:42,680 --> 00:46:47,280
who can survive winter
at the farthest ends of our planet.

301
00:47:29,600 --> 00:47:31,840
More than any other season in the poles,

302
00:47:31,960 --> 00:47:35,680
winter was to pose the greatest
challenge to the Frozen Planet crew.

303
00:47:37,080 --> 00:47:39,880
The team endured winds of
over 100 miles an hour

304
00:47:40,000 --> 00:47:43,400
and temperatures as
low as -50 degrees centigrade.

305
00:47:44,560 --> 00:47:47,160
Their boats were trapped in
sea-ice for days,

306
00:47:47,280 --> 00:47:50,000
while bears trapped others indoors.

307
00:47:55,000 --> 00:47:57,080
Some of the coldest
conditions experienced

308
00:47:57,200 --> 00:47:59,880
were near the Arctic circle
in Northern Canada.

309
00:48:01,200 --> 00:48:05,040
In winter, temperatures dropped to
-40 degrees and stayed there.

310
00:48:07,320 --> 00:48:09,800
On the edge of the vast Taiga forest,

311
00:48:09,920 --> 00:48:12,200
the team hoped to film one
the most remarkable

312
00:48:12,320 --> 00:48:14,640
predator-prey relationships
on the planet.

313
00:48:16,480 --> 00:48:20,160
What they experienced was the
struggle against the elements,

314
00:48:20,320 --> 00:48:24,760
what they witnessed was a more profound
struggle for life and death.

315
00:48:35,640 --> 00:48:39,960
Wood Buffalo National Park
covers 28,000 square miles,

316
00:48:40,080 --> 00:48:41,440
the size of Denmark.

317
00:48:42,400 --> 00:48:47,000
One of the few cameramen to have filmed
wolves and bison here is Jeff Turner.

318
00:48:47,640 --> 00:48:49,720
I first tried to film
bison and wolves

319
00:48:49,840 --> 00:48:54,760
in this national park 15 years ago
and getting around on the ground

320
00:48:54,880 --> 00:48:58,840
is incredibly difficult at any time of
the year, but in the winter it's tough.

321
00:48:58,960 --> 00:49:02,040
We quickly realized that the only way
we were going to get anything here

322
00:49:02,200 --> 00:49:04,160
was we had to get up in the air.

323
00:49:04,280 --> 00:49:05,600
The Frozen Planet team

324
00:49:05,720 --> 00:49:08,800
had never attempted aerial filming
in such low temperatures.

325
00:49:11,480 --> 00:49:13,880
The first challenge
for director Chadden Hunter

326
00:49:14,000 --> 00:49:16,320
was protecting the sensitive
aerial camera,

327
00:49:16,440 --> 00:49:20,920
at -40, electrical cables
short-circuit like fireworks.

328
00:49:22,440 --> 00:49:23,720
- Oh!
- Ooh.

329
00:49:24,360 --> 00:49:27,920
- How cold can you fly this chopper?
- Minus-40.

330
00:49:28,160 --> 00:49:32,000
Aerial cameraman Michael
Kelem comes from sunny California

331
00:49:32,120 --> 00:49:34,600
and has never experienced
temperatures so low.

332
00:49:34,720 --> 00:49:37,480
What kind of temperatures
can you operate down to?

333
00:49:37,600 --> 00:49:41,200
Me, usually about 70 degrees
Fahrenheit. LA kind of weather,

334
00:49:41,320 --> 00:49:43,440
- Yeah.
- I'm only rated for Santa Monica.

335
00:49:44,920 --> 00:49:47,920
Operating delicate
controls while wearing gloves

336
00:49:48,040 --> 00:49:51,360
is not easy.
A computer and joystick are needed

337
00:49:51,480 --> 00:49:55,040
to control the aerial camera attached
to the outside of the helicopter.

338
00:49:55,160 --> 00:49:56,920
It's actually warmed up to -30.

339
00:49:57,040 --> 00:50:01,160
Michael would have to
choose between dexterity or warmth.

340
00:50:03,680 --> 00:50:05,360
With their camera mounted on the nose,

341
00:50:05,480 --> 00:50:09,440
the aerial team could now fly hundreds
of miles in search of the animals.

342
00:50:11,200 --> 00:50:12,960
Jeff, meanwhile, is still on foot,

343
00:50:13,080 --> 00:50:15,520
scouting the other side
of the national park.

344
00:50:16,160 --> 00:50:17,920
I wonder what Jeff’s getting
on the ground?

345
00:50:18,040 --> 00:50:19,840
Oh, man, it's cold.

346
00:50:20,320 --> 00:50:23,240
With the wind today it's about -37

347
00:50:23,360 --> 00:50:25,520
so you got to keep
these heaters in here,

348
00:50:25,640 --> 00:50:27,680
to keep the camera running
at these temperatures.

349
00:50:28,760 --> 00:50:30,280
From 3,000 feet up,

350
00:50:30,400 --> 00:50:33,360
Chadden catches a glimpse
of the elusive wolf pack.

351
00:50:34,520 --> 00:50:37,320
I can see wolves,
I can see wolves near buffalo.

352
00:50:37,440 --> 00:50:39,880
- 10, 15, there's a big pack.
- Wow.

353
00:50:40,040 --> 00:50:42,240
We've got a big pack of wolves here.

354
00:50:42,400 --> 00:50:47,080
The wolf pack turns out to
number an extraordinary 25 individuals,

355
00:50:47,200 --> 00:50:48,880
one of the largest ever filmed.

356
00:50:49,000 --> 00:50:51,120
There's two more walking in
from the left.

357
00:50:51,240 --> 00:50:54,040
And it looks like
they're already on the hunt.

358
00:50:54,160 --> 00:50:58,200
The helicopter allows the team to shadow
the wolf pack without disturbing them.

359
00:50:58,320 --> 00:51:02,600
So, let's go back into
nice, slow circle around them.

360
00:51:03,840 --> 00:51:05,600
They look pretty determined.

361
00:51:05,720 --> 00:51:07,640
The pack are moving in
on their prey

362
00:51:07,760 --> 00:51:10,280
and the aerial team
are perfectly placed.

363
00:51:13,880 --> 00:51:15,480
They're making their...
definitely making their move.

364
00:51:15,600 --> 00:51:18,560
Wow,
there's buffalo on the move.

365
00:51:19,600 --> 00:51:22,640
- The chase is on.
- Extreme concentration is now needed

366
00:51:22,760 --> 00:51:25,840
both from pilot and the cameraman
to keep the shots smooth.

367
00:51:28,640 --> 00:51:30,160
Yeah, there's more coming in now.

368
00:51:30,280 --> 00:51:32,440
There's a nice, tight little pack
challenging them.

369
00:51:32,560 --> 00:51:34,200
We've got a nice shot of the pack,

370
00:51:34,320 --> 00:51:36,920
the wolves coming up at the back.
You got them still?

371
00:51:37,040 --> 00:51:38,880
Yeah, I got them here, I'm just
going to pick it up a little bit.

372
00:51:39,040 --> 00:51:42,200
Okay, okay, tighten up, just a hair.

373
00:51:42,320 --> 00:51:44,920
Just want to get a shot
of the wolves at the back of the pack.

374
00:51:45,080 --> 00:51:47,840
The wolf pack
have picked out a young bison.

375
00:51:49,560 --> 00:51:50,840
Holy.

376
00:51:51,240 --> 00:51:53,560
As Michael struggles
to hold the shot steady,

377
00:51:53,680 --> 00:51:55,840
no one is prepared for what came next.

378
00:51:56,320 --> 00:52:00,200
Oh, hey, look,
they just knocked him down, pretty much.

379
00:52:01,560 --> 00:52:03,200
A one-ton bull charges through,

380
00:52:03,320 --> 00:52:06,440
taking out both the wolves
and the young bison.

381
00:52:08,440 --> 00:52:12,480
I've never seen anything like that
in the wild, that is unbelievable.

382
00:52:13,600 --> 00:52:16,520
The team have filmed
extraordinary new behavior from the air

383
00:52:16,640 --> 00:52:18,840
but Jeff was nowhere nearby.

384
00:52:20,080 --> 00:52:22,800
To complete the sequence,
they will need to work together,

385
00:52:22,920 --> 00:52:25,560
only by using the helicopter
to position Jeff

386
00:52:25,680 --> 00:52:29,200
will they able to get both air
and ground coverage.

387
00:52:38,480 --> 00:52:42,760
This pack will now feast for days,
so the crew must move on.

388
00:52:44,800 --> 00:52:47,080
Jeff takes the team deeper
into the wilderness

389
00:52:47,200 --> 00:52:49,720
in search of a new wolf pack.

390
00:52:49,840 --> 00:52:53,400
With everyone on board,
there are more eyes for spotting.

391
00:52:54,560 --> 00:52:57,920
Bison on the run can only mean
one thing, wolves.

392
00:52:58,360 --> 00:53:01,600
But this time, only a pair.

393
00:53:02,720 --> 00:53:05,440
Jeff must anticipate the animals'
every move

394
00:53:05,560 --> 00:53:09,080
and direct the helicopter to
where he needs to be dropped off.

395
00:53:09,200 --> 00:53:10,640
They're going this way.

396
00:53:12,600 --> 00:53:14,120
I had to figure out exactly

397
00:53:14,240 --> 00:53:16,921
where the buffalo were going to run,
try to get there ahead of them.

398
00:53:18,000 --> 00:53:21,080
If I got dropped off
in the wrong position, we would blow it.

399
00:53:22,440 --> 00:53:24,360
There wasn't going to be
a second chance.

400
00:53:33,920 --> 00:53:36,240
That moment when you get
out of the helicopter

401
00:53:36,360 --> 00:53:40,640
and it leaves you behind, you feel
an incredible sense of isolation.

402
00:53:43,400 --> 00:53:44,840
On the lake, I'll guide you in,

403
00:53:44,960 --> 00:53:48,400
down to the right, down, zoom in.

404
00:53:49,480 --> 00:53:52,600
- Are you on the back guy?
- We're on the back guy. On the back.

405
00:53:53,320 --> 00:53:55,680
- Which one is he going for?
- I don't know.

406
00:53:56,080 --> 00:53:57,880
- But there's one broken off.
- Oh!

407
00:53:58,520 --> 00:54:01,480
- Oh, my God.
- They're coming in now.

408
00:54:02,760 --> 00:54:04,280
When I saw the herd
coming around the corner,

409
00:54:04,400 --> 00:54:07,720
I knew we'd picked the right spot,
I was right in front of them.

410
00:54:09,120 --> 00:54:10,840
And the buffalo
running right towards you,

411
00:54:10,960 --> 00:54:12,880
it definitely does get your
heart pounding.

412
00:54:15,320 --> 00:54:16,840
The bison have poor eyesight

413
00:54:16,960 --> 00:54:20,320
and can't see Jeff.
It's now test of nerves.

414
00:54:21,320 --> 00:54:24,000
Weighing one ton
and running at 40 miles an hour,

415
00:54:24,120 --> 00:54:26,840
one wrong step
and the bison could kill Jeff.

416
00:54:27,240 --> 00:54:28,480
At the last second,

417
00:54:28,600 --> 00:54:31,240
they spot him and three peel
away to the other side.

418
00:54:34,680 --> 00:54:37,680
At the back of the herd,
the wolves have closed in.

419
00:54:39,400 --> 00:54:42,520
They're still at him. They're trying to
separate that little one.

420
00:54:45,920 --> 00:54:48,960
- Oh, they got him!
- Both wolves are on him.

421
00:54:49,080 --> 00:54:51,000
- Both clamping down on him.
- Yeah, he got stomped.

422
00:54:51,120 --> 00:54:52,240
He got stomped on there.

423
00:54:52,400 --> 00:54:55,960
What followed was one of
the most emotional and powerful scenes

424
00:54:56,080 --> 00:54:58,480
the Frozen Planet team
were ever to film.

425
00:55:00,320 --> 00:55:03,120
Jeff has picked his position perfectly,

426
00:55:03,240 --> 00:55:05,680
he is now only 50 meters
from the animals

427
00:55:05,800 --> 00:55:08,400
and able film a truly epic battle.

428
00:55:10,080 --> 00:55:12,920
I had never been so close
to a wolf and bison battle,

429
00:55:13,840 --> 00:55:15,960
I could hear them breathing.

430
00:55:16,960 --> 00:55:18,880
And the power of the buffalo,

431
00:55:19,000 --> 00:55:22,320
the way he just threw this wolf around
like it was a rag doll.

432
00:55:23,360 --> 00:55:25,800
I couldn't believe the beating
this wolf was taking.

433
00:55:29,920 --> 00:55:33,640
The struggles that we'd had with
the winter and the cold and the snow

434
00:55:33,760 --> 00:55:37,760
just felt so insignificant
compared to these two animals

435
00:55:37,880 --> 00:55:40,080
that were struggling
for their very lives.

436
00:55:43,280 --> 00:55:46,240
For over an hour,
I watched this wolf and bison

437
00:55:46,360 --> 00:55:48,520
battle each other to a standstill.

438
00:55:50,120 --> 00:55:52,440
They were both unbelievably exhausted.

439
00:56:00,400 --> 00:56:04,240
Watching these two animals engaged
in this massive life and death struggle

440
00:56:04,360 --> 00:56:08,000
was one of the most powerful things
I'd ever witnessed in the wild.

441
00:56:10,560 --> 00:56:14,280
As a filmmaker, you're definitely torn
watching something like this.

442
00:56:14,400 --> 00:56:18,040
You know you need to keep filming
and you know this a natural event,

443
00:56:18,600 --> 00:56:20,760
but it's also incredibly sad
to know that

444
00:56:20,880 --> 00:56:24,160
one of these two magnificent
animals isn't going to make it.

445
00:56:28,560 --> 00:56:33,000
The bison is fatally
wounded, the battle is over.

446
00:56:36,000 --> 00:56:39,160
The team have managed
to capture a remarkable hunt

447
00:56:39,280 --> 00:56:41,840
from both ground and air.

448
00:56:42,520 --> 00:56:44,080
All of them have been humbled

449
00:56:44,200 --> 00:56:48,000
by witnessing an extraordinary
winter struggle for survival.

450
00:56:55,925 --> 00:57:01,125
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