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The power of the sun

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drives the seasons,
transforming our planet.

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Vast movements of ocean and air currents

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bring dramatic change
throughout the year.

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And in a few special places,
these seasonal changes

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create some of the greatest
wildlife spectacles on Earth.

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Here in the Arctic each summer,
the sun begins to melt the winter ice.

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Nearly three million square miles of ice
will disappear,

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opening up a narrow window of
opportunity for millions of animals.

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For many, it's their best chance
to feed and breed.

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But for polar bears,
it's the hardest time of the year.

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They have to survive the greatest
seasonal change on the planet.

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Winter in the Arctic.

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The northern lights
flicker across the sky.

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It's a land of continuous night

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where temperatures plummet to minus 40.

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Polar bears are in their element,

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hunting for seals on the frozen sea.

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But the long night is coming to an end.

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In February the sun rises

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for the first time in four months.

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In the coming weeks
the strength of the sun

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will power an enormous change.

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But for now its rays offer
only a little warmth.

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Despite the sun's return, six million
square miles of the planet's far north

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is still cloaked in ice.

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Deep snow covers the mountains.

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Even the sea is frozen solid,
many metres deep.

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Groups of ringed seals
haul out through holes in the ice

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to bask in the weak sunlight.

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But they are vulnerable
and have to keep a lookout.

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With the sea still frozen,
it's easier for predators to get close,

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and the seal's greatest enemy
is the polar bear.

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A mother bear and her four-month-old cub
are hunting.

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Seals make up most of the bear's diet,

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and to find them she must lead
her youngster out onto the ice

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for the first time.

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Scientists, looking at how
a changing climate is affecting bears,

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have fitted the female
with a radio collar.

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The ice here is thinner,

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and she must spread her weight
to avoid breaking through.

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For her cub, it's all just a game.

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By sticking close to Mum,
he'll learn how she hunts for seals,

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a critical lesson
for his future survival.

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At this time of year
the frozen Arctic is empty of life

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and only a few hardy residents
can survive.

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For a female arctic fox,
the winter has been a time of hunger.

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Food is scarce and she's had
to wander far and wide,

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scavenging from the remains
of bear kills.

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But her fortunes are changing.

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A dead reindeer is a lucky find.

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If no other scavengers come along,

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this could sustain her
for the rest of the winter.

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With the sea frozen,
polar bears are busy hunting.

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This bear has caught a seal.

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He waited for it to surface
through a hole in the ice

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and his patience has been rewarded.

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He must catch a seal about once a week,
and this is the best hunting season.

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As long as there is sea ice
the bears won't go hungry,

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as walking on the ice is the easiest way
for a bear to get close to a seal.

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But the ice will soon start to break up
and hunting will get harder.

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The calories the bear takes in now

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will have to see him
through hard times ahead.

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For polar bears
it's the survival of the fattest.

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At this time of year there are still
only five hours of daylight.

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But as the sun rises higher,
each day lasts 40 minutes longer.

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It's March, and with increasing sunlight

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the first in a huge wave of migrants
are arriving.

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Millions of seabirds are travelling
north to reach the frozen coast.

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Huge flocks of little auks
and guillemots

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fly across many miles of ice
from the nearest open water.

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Their destination is
the still-frozen sea cliffs.

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It's an inhospitable place,

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but in a few weeks
everything here will change.

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It pays to be early, even though
the snow has yet to melt.

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The first arrivals get the best
nesting ledges and a head start.

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They have just 50 days from
laying their eggs to raise their chicks.

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The Arctic's silent wilderness
is coming to life.

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It's three months since the sun's return
and its power is growing daily.

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The air temperature rises slowly

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and once above zero,
at long last, the melt begins.

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Melting snow feeds freshwater streams
which pour off the land.

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In just a few short days,
the melt unveils a whole new landscape.

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The coastal cliffs
now teem with nesting seabirds,

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and it's not long before
they attract unwelcome attention.

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The fox's white winter coat
has disappeared with the snow.

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Her new camouflage will allow her
to change from scavenger to hunter.

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The short summer will be
her best chance to raise a family.

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The snow may be
disappearing from the land,

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but the sea ice has yet to melt.

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The coastline is still locked in ice.

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The islands of the Arctic

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are surrounded by thousands of miles
of white frozen ocean.

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Because the sea ice is so thick,
it won't begin to break up

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until the temperature stays above zero
for a number of days.

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Until then, few creatures can penetrate
this icy barrier.

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The sun reflects from
the white frozen sea,

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creating a desert of icy mirage.

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The bear can still walk on the ice
to hunt for seals,

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but not for much longer.

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It's getting warmer by the day.

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The bear's world is about to melt away.

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It's now June and the sun beats down
24 hours a day.

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The temperature remains constant
above zero degrees.

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The frozen sea begins to melt.

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Pools form across the surface,
absorbing more of the sun's heat,

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speeding the thaw.

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Sunlight penetrates the frozen surface,

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illuminating a strange world
beneath the ice.

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The frozen barrier has split.

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Mysterious voices echo
against the icy ceiling.

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Giant cracks, or leads,
form at weak points,

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creating a pathway for new arrivals.

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Narwhal.

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Known as the arctic unicorn
because of their strange spiral tusks,

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narwhal are some of
the most secretive and elusive animals

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in the world's oceans.

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The leads provide passage for thousands
of these mysterious whales.

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Each summer they travel 600 miles north,

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navigating through the ice
to reach rich fishing grounds.

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More whales travel along the edge
of the ice where it meets the open sea,

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to search for the openings of leads.

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It's a hazardous journey.
As mammals, they need air to breath

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and if the ice closes above them
they could suffocate.

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They're looking for holes in the ice
where they can surface.

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A single breath
will last them for 15 minutes.

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The further they travel, the harder it
becomes to find holes in the ice.

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They snatch a breath and then travel on.

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But ahead, the ice forms
an impenetrable barrier.

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The narwhal use their heads
and their long tusks

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to break the ice
and enlarge the breathing holes.

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For now they've reached a dead end
and must wait.

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The ice will need to melt further
if they are to continue.

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All across the Arctic
the sea ice is beginning to retreat.

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The leads widen,
forming tracts of open water.

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Wind and ocean currents
shift the loosening ice, breaking it up.

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As the ice melts, thousands of miles
of open ocean become accessible,

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providing a bonanza
for millions of seabirds.

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In just four weeks
a colony of guillemots

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can devour one and a half
million tonnes of arctic fish.

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As the ice melts, their journey to
their feeding grounds in the open sea

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shortens by the day.

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They gather at the edge
of the retreating ice

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and dive to hunt
for arctic cod and capelin.

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The shoals are found 80 metres down
in the murky depths,

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and the guillemots must hold
their breath for nearly two minutes.

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With their crops stuffed with fish,
they return to the colony

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to feed their hungry youngsters.

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With 24 hours of daylight,
they go on fishing around the clock.

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Warmed by the sun
and driven by winds and currents,

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the sea ice is now fragmenting.

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That is a big problem
if you need the ice to hunt from.

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A polar bear can smell a seal
from over a mile away.

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But the prey he depends on
is hard to find

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in this constantly moving landscape.

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He must take to the water to navigate
through the drifting maze of ice.

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Bears are excellent swimmers,
but he's no match for a seal.

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As the ice melts,
finding seals gets harder

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and with more open water,
it's easier for a seal to escape.

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The melt has caused a shift in power.

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Now it's "advantage seal".

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The bear's chance has slipped away,
and his hunger grows.

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The ice barrier broken,

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strange marine visitors begin to arrive.

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They've swum 600 miles to get here,
and with the ice gone

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they can make their way into
the shallows of freshwater estuaries.

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Beluga whales.

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As more and more belugas arrive,

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a strange annual ritual begins.

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For belugas, this is
a very special event.

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The violent thrashing against the
river bed loosens their year-old skin

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and rids them of unwelcome parasites

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they may have picked up
on their journey.

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In freshwater,
warmed by the strengthening sun

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and with the smooth
pebbles in the shallows to rub against,

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the whales whistle with pleasure.

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But the ice-free summer will be short.

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The whales can only enjoy
their arctic spa for two weeks.

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Soon the belugas must leave the shallows

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and make the most of
what's left of the summer

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to hunt the shoals of arctic fish.

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It's early July,

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and at the bird cliff
the fox has caught a nesting fulmar.

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She has a family now,
eight tiny mouths to feed,

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and one bird is not enough to go round.

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The cubs bicker over their dinner.

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They're only three weeks old
and in just another two weeks

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they'll have to be ready
to fend for themselves.

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The winter ahead will be so harsh that
only two of these eight cubs

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are likely to gain enough weight
to survive.

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Their lives depend on every mouthful.

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When food is scarce
the most dominant cub will feed.

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And the smallest will go hungry.

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The seabirds have been working
round the clock to keep their chicks fed

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and to prepare them for
the first big challenge of their lives.

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If they are to escape the winter,

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they'll have to leave the cliffs
right away, and get far out to sea.

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But it's only been 20 days
since they hatched

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and their wings are
still too weak for them to fly.

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So far their feet
have never left the ground

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and there is only one way down
to the safety of the sea,

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300 metres below.

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Reluctantly, the chicks take
a few nervous steps towards the edge.

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Encouraged by a gentle nudge,

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he leaps into the unknown.

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Dad follows right behind him,
reassuringly calling to his chick.

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Made it.

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The landings may not be stylish,
but at least they're on target.

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It's easy to misjudge the distance
and some fall short of the water.

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But even now, Dad sticks close by.

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He encourages his chick
to take the last few steps

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towards the safety of the waves.

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But some chicks
land a long way from the water.

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They're sturdy enough
to survive the fall,

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but this is no place to be left alone.

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For the mother fox it's easy pickings.

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With so many free meals
falling from the sky,

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she runs from one kill to the next.

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The chicks will be jumping
for only three days,

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so she must make the most
of this bonanza.

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The survival of her own family
depends on it.

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With more chicks
than she can possibly carry,

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the mother fox has to be clever.

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What her family can't eat now,
she buries.

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For the days ahead
she'll have a well-stocked larder,

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enough for all eight of her cubs.

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Their bellies now full at last,
the cubs can relax in the sun.

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For the guillemot chicks that survive,
the ordeal has only just begun.

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They must retreat south 600 miles,
beyond the reach of winter.

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But the youngsters can't fly yet,
their wings aren't strong enough.

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So, led by their parents,
they'll have to swim.

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At the height of summer
even the permanent ice caps

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are touched by the power of the sun.

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Melt-water, channelled down
from high on these ice caps,

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pours over a precipice
where the ice meets the ocean.

237
00:31:34,935 --> 00:31:37,495
Along this 200-mile wall of ice,

238
00:31:37,575 --> 00:31:41,773
a thousand freshwater cascades
plummet into the sea.

239
00:31:59,975 --> 00:32:04,730
As July draws on,
the great melt reaches its peak.

240
00:32:11,215 --> 00:32:15,925
The greatest seasonal change
on the planet has taken place.

241
00:32:29,495 --> 00:32:33,408
The sea ice that once extended
all the way to the horizon

242
00:32:33,495 --> 00:32:35,645
is now open ocean.

243
00:32:38,535 --> 00:32:43,689
In just three months, the sun has won
its battle with the ice.

244
00:32:46,415 --> 00:32:50,806
Over two and a half million square miles
of ice has melted away,

245
00:32:50,895 --> 00:32:55,571
uncovering thousands of islands
surrounded by open ocean.

246
00:32:55,655 --> 00:33:00,012
But in recent years, the scale
of this melt has been growing.

247
00:33:02,095 --> 00:33:05,974
And for one animal
this is a critical issue.

248
00:33:22,455 --> 00:33:25,492
A mother bear and her adolescent cub

249
00:33:25,575 --> 00:33:28,453
rest on a fragment of sea ice.

250
00:33:29,135 --> 00:33:32,889
With the melt, they're forced
to swim ever-greater distances

251
00:33:32,975 --> 00:33:34,931
to hunt for seals.

252
00:33:38,855 --> 00:33:43,451
Their arctic home is increasingly
vulnerable to a changing climate,

253
00:33:43,535 --> 00:33:47,164
and this year there has been
even less ice than normal.

254
00:33:53,175 --> 00:33:56,372
If future melts
are as extreme as this one,

255
00:33:56,455 --> 00:34:01,449
bears like these
may starve or drown, lost at sea.

256
00:34:08,655 --> 00:34:13,888
This is one of the last pieces of ice
now adrift in the open ocean.

257
00:34:14,575 --> 00:34:18,773
The polar bear's icy world
has melted away.

258
00:34:29,375 --> 00:34:34,495
For many others the open water
provides the greatest feast of the year.

259
00:34:35,575 --> 00:34:38,009
The narwhal have
made it through the ice.

260
00:34:38,095 --> 00:34:42,486
They gather in bays where they can hunt
for arctic cod and squid.

261
00:34:56,055 --> 00:34:59,411
Here they are joined
by other ocean migrants.

262
00:35:03,455 --> 00:35:05,411
Bowhead whales.

263
00:35:06,655 --> 00:35:11,604
These 100-tonne giants
feed on millions of tiny plankton

264
00:35:11,695 --> 00:35:14,334
that flourish in the sunlit waters.

265
00:35:25,375 --> 00:35:28,094
Belugas have come for the rich fishing

266
00:35:28,175 --> 00:35:31,292
and rest on the surface between dives.

267
00:35:39,455 --> 00:35:43,050
Even on the sea bed
there is plenty on the menu.

268
00:35:53,455 --> 00:35:56,731
Two tonnes of pulsating blubber

269
00:35:56,815 --> 00:35:59,648
forages for clams in the sediment.

270
00:35:59,735 --> 00:36:02,647
Walrus are year-round residents
of the Arctic,

271
00:36:02,735 --> 00:36:05,374
following the ebb and flow of the ice.

272
00:36:06,735 --> 00:36:11,126
In the open summer waters they
can reach huge areas of the ocean floor,

273
00:36:11,215 --> 00:36:14,491
rich feeding grounds
for these giant seals.

274
00:36:16,895 --> 00:36:20,444
They hoover up clams
with their rubbery lips.

275
00:36:20,535 --> 00:36:25,848
A single walrus can eat up to
4,000 clams in one 10-minute dive.

276
00:36:34,335 --> 00:36:37,247
Bellies full, they come up for air.

277
00:36:51,775 --> 00:36:56,565
With the sea ice gone,
the walrus haul out on dry land to rest.

278
00:37:00,015 --> 00:37:02,848
They're used to huddling together
to keep warm,

279
00:37:02,935 --> 00:37:06,484
and even now that
it's 12 degrees above freezing,

280
00:37:06,575 --> 00:37:09,373
they prefer to stick close together.

281
00:37:09,455 --> 00:37:13,448
In the warmth of the sun, the walrus
begin to shed their old skin,

282
00:37:13,535 --> 00:37:15,924
and they spend hours scratching.

283
00:37:19,055 --> 00:37:22,491
Some places are
harder to reach than others.

284
00:37:26,855 --> 00:37:31,804
These irritations make them bad-tempered
and arguments often break out.

285
00:37:44,935 --> 00:37:49,406
Spitting, stabbing and bellowing
iron out any disagreements.

286
00:37:55,095 --> 00:38:00,044
All disputes settled,
a peace of sorts returns once more.

287
00:38:06,655 --> 00:38:11,046
Digesting a belly full of clams
generates a lot of wind,

288
00:38:11,135 --> 00:38:15,731
making walrus colonies
very fragrant places.

289
00:38:34,895 --> 00:38:38,092
Fed by the abundant supply
of guillemot chicks,

290
00:38:38,175 --> 00:38:42,646
all eight fox cubs seem to have
boundless energy.

291
00:38:42,735 --> 00:38:46,648
Soon they will be ready to face
the world without their mother.

292
00:38:56,895 --> 00:38:59,887
In just five weeks
she's raised her cubs,

293
00:38:59,975 --> 00:39:02,614
making the most of the short summer.

294
00:39:09,015 --> 00:39:12,894
The mother fox has won
her race against time.

295
00:39:17,855 --> 00:39:22,975
Between June and July, the Arctic
is the land of the midnight sun.

296
00:39:23,255 --> 00:39:26,645
An empty wilderness
has been transformed.

297
00:39:52,215 --> 00:39:56,333
The once-frozen ocean
is now bursting with life,

298
00:39:56,415 --> 00:39:59,373
as all the animals
enjoy the summer feast.

299
00:40:30,175 --> 00:40:33,929
But polar bears aren't so fortunate.

300
00:40:36,135 --> 00:40:41,050
With no sea ice to hunt on,
they're now trapped on dry land.

301
00:40:43,775 --> 00:40:47,973
A hungry bear will eat any food
it can get its paws on,

302
00:40:48,055 --> 00:40:52,890
but for a meat-eater
a few scraps of dry lichen won't go far.

303
00:40:58,175 --> 00:41:02,168
It may have been four months
since his last kill

304
00:41:02,255 --> 00:41:04,689
and he won't find any seals here.

305
00:41:07,455 --> 00:41:11,243
If the yearly increase
in the scale of the melt continues,

306
00:41:11,335 --> 00:41:13,769
more bears will starve.

307
00:41:13,855 --> 00:41:19,009
Two thirds of the world's polar bears
could vanish by 2050.

308
00:41:22,055 --> 00:41:25,206
The great melt has always
been difficult for bears,

309
00:41:25,295 --> 00:41:29,447
but soon surviving the summer
may become impossible.

310
00:41:32,615 --> 00:41:36,893
The scale of the summer melt has changed
over the last 30 years.

311
00:41:36,975 --> 00:41:41,366
2007's melt broke all records.

312
00:41:42,335 --> 00:41:46,453
400,000 extra square miles of ice
disappeared,

313
00:41:46,535 --> 00:41:49,925
the greatest melt ever recorded.

314
00:41:50,015 --> 00:41:55,328
The latest predictions suggest that
the Arctic may be entirely ice-free

315
00:41:55,415 --> 00:41:58,487
in summertime within 20 to 40 years.

316
00:42:03,975 --> 00:42:07,331
By September, the sun's power
begins to ebb.

317
00:42:07,415 --> 00:42:11,727
The summer comes to an end
and the Arctic empties of life.

318
00:42:12,895 --> 00:42:15,728
The last seabirds
begin their long journey south,

319
00:42:15,815 --> 00:42:19,205
leaving only a few
hardy residents behind.

320
00:42:23,855 --> 00:42:28,451
The fox cubs now face
the changing season alone.

321
00:42:34,855 --> 00:42:38,211
Already, the first snow
is beginning to fall.

322
00:42:38,295 --> 00:42:42,573
The full Arctic winter
is just six weeks away.

323
00:42:54,175 --> 00:42:58,885
For hungry bears,
six weeks may be too long to wait.

324
00:43:00,855 --> 00:43:05,326
The sea ice will not freeze properly
till it reaches minus 2 degrees.

325
00:43:05,415 --> 00:43:08,054
For now, it's still too warm.

326
00:43:10,135 --> 00:43:15,289
This ice is no use to the bears.
They can't walk on it to hunt.

327
00:43:24,895 --> 00:43:28,285
The normally unsocial bears
gather in groups,

328
00:43:28,375 --> 00:43:30,730
trapped on the shoreline.

329
00:43:34,775 --> 00:43:39,166
This is the time of year
the male bears spar.

330
00:43:42,335 --> 00:43:46,123
Only the biggest bears have
the energy reserves to fight.

331
00:43:46,215 --> 00:43:50,766
After a summer without food,
the bear's systems are in low gear.

332
00:43:50,855 --> 00:43:53,289
These aerobics help warm them up,

333
00:43:53,375 --> 00:43:56,173
in readiness for
the winter hunting ahead.

334
00:44:45,975 --> 00:44:50,890
It's late October,
but still the sea hasn't frozen.

335
00:44:50,975 --> 00:44:53,967
For every degree rise
in the average temperature,

336
00:44:54,055 --> 00:44:57,650
the summer melt is extended
by a whole week.

337
00:44:57,735 --> 00:45:00,568
That's more bad news for polar bears.

338
00:45:09,935 --> 00:45:14,725
Smaller, younger bears don't have
the energy of the big males.

339
00:45:14,815 --> 00:45:19,605
Each day they are without food,
they lose nearly a kilo.

340
00:45:19,695 --> 00:45:22,448
Some have lost
half of their body weight.

341
00:45:24,735 --> 00:45:29,763
These hungry bears must now rest
in the snow and conserve energy.

342
00:45:30,455 --> 00:45:32,491
All they can do is wait.

343
00:45:44,775 --> 00:45:47,653
At last the wind changes,

344
00:45:47,735 --> 00:45:51,045
blowing from the cold north
across the sea.

345
00:45:51,135 --> 00:45:54,844
The air temperature
plummets to 20 degrees below.

346
00:45:55,975 --> 00:46:00,014
It's now cold enough
for ice crystals to form in the ocean.

347
00:46:00,095 --> 00:46:04,805
They knit together
forming a greasy layer of surface ice.

348
00:46:06,255 --> 00:46:08,086
This thickens into plates

349
00:46:08,175 --> 00:46:12,566
which bump and collide in the swell,
forming pancake ice.

350
00:46:18,615 --> 00:46:23,245
These pancakes lock together
to form a continuous surface.

351
00:46:29,455 --> 00:46:32,765
At long last the sea has frozen.

352
00:46:37,215 --> 00:46:42,687
Only now can the bears head out
onto the sea ice to hunt for seals.

353
00:46:43,895 --> 00:46:46,853
But the new ice has a surprise in store.

354
00:47:03,455 --> 00:47:07,164
This season,
for the first time ever recorded,

355
00:47:07,255 --> 00:47:09,894
even the winter ice is thinner.

356
00:47:15,175 --> 00:47:18,451
The ice here is too thin to climb out on

357
00:47:18,735 --> 00:47:21,124
and he struggles to free himself.

358
00:48:03,215 --> 00:48:06,252
At last, safely on the firmer ice,

359
00:48:06,335 --> 00:48:09,407
he rolls in the snow to dry his fur.

360
00:48:23,335 --> 00:48:28,045
In November, the sun sets
over the frozen north.

361
00:48:28,135 --> 00:48:31,286
It will not appear again
for four months.

362
00:48:36,375 --> 00:48:40,607
The summer melt provides opportunities
for millions of animals,

363
00:48:40,695 --> 00:48:45,086
but has now become a threat
to the polar bear's very survival.

364
00:48:47,735 --> 00:48:52,684
This season, the bear has survived
the greatest melt yet recorded

365
00:48:53,175 --> 00:48:56,611
and made it through
to the Arctic winter.

366
00:49:19,575 --> 00:49:24,285
The frozen Arctic sea is one of
the most demanding of all environments,

367
00:49:24,375 --> 00:49:27,447
and the location
for a rarely seen spectacle.

368
00:49:28,815 --> 00:49:31,204
<i>The Nature's Great Events team</i>

369
00:49:31,295 --> 00:49:36,210
wanted to film the annual migration
of the elusive arctic narwhal.

370
00:49:37,215 --> 00:49:42,369
To do so, they would have to live on,
dive beneath and fly over the ice

371
00:49:42,655 --> 00:49:45,613
during the climax of the great melt.

372
00:49:55,215 --> 00:49:59,527
The quest for the narwhal started
at the height of the melt, in July,

373
00:49:59,615 --> 00:50:02,527
when the sea ice
was at its most dangerous.

374
00:50:02,615 --> 00:50:06,893
This made the task of first finding
the whales a tough prospect.

375
00:50:11,855 --> 00:50:16,451
This is rough ice. And we're stuck.

376
00:50:18,175 --> 00:50:19,449
Narwhal are so elusive

377
00:50:19,535 --> 00:50:22,095
and the conditions working
on the ice so difficult,

378
00:50:22,175 --> 00:50:26,612
that the crew allowed a month
to track them down.

379
00:50:26,695 --> 00:50:29,334
The plan was to get to
the edge of the ice

380
00:50:29,415 --> 00:50:33,727
in the hope of finding the whales
at the beginning of their migration.

381
00:50:37,735 --> 00:50:42,251
The melt was in full swing and
the team were in the thick of it.

382
00:50:44,295 --> 00:50:48,493
With 24-hour sunlight, the leads
along which the narwhal migrate

383
00:50:48,575 --> 00:50:50,850
were getting wider every day.

384
00:50:59,855 --> 00:51:01,607
After three weeks of searching,

385
00:51:01,695 --> 00:51:05,244
the whales were living up
to their secretive reputation.

386
00:51:13,855 --> 00:51:16,130
The crew couldn't see the narwhal,

387
00:51:16,215 --> 00:51:18,775
but there was evidence that
they were not far away.

388
00:51:18,855 --> 00:51:22,643
A sensitive hydrophone enabled
them to eavesdrop on the whales

389
00:51:22,735 --> 00:51:24,214
under the ice.

390
00:51:29,215 --> 00:51:32,969
I am hearing what could be
sedation whistles and clicks.

391
00:51:33,055 --> 00:51:34,886
So it could be narwhal.

392
00:51:38,895 --> 00:51:41,887
It's very distant and sound travels
a long way under water,

393
00:51:41,975 --> 00:51:45,092
so these guys are probably still far
away, but it's a good sign. It's good.

394
00:51:46,375 --> 00:51:48,093
They could hear the whales,

395
00:51:48,175 --> 00:51:50,689
but would they be able to see them?

396
00:51:51,735 --> 00:51:56,525
By now the cracks had opened wide enough
for them to dive to search for them.

397
00:51:59,415 --> 00:52:02,248
Ice diving is dangerous
at the best of times,

398
00:52:02,335 --> 00:52:06,374
but in such a remote location,
days away from the nearest help,

399
00:52:06,455 --> 00:52:08,923
they had to be especially careful.

400
00:52:12,735 --> 00:52:14,726
Even though it was
the height of the summer,

401
00:52:14,815 --> 00:52:19,013
the icy sea water was still
a chilly minus 1.6 degrees.

402
00:52:20,095 --> 00:52:23,326
So the team needed
not only specialist equipment

403
00:52:23,415 --> 00:52:25,610
but specialist attitude.

404
00:52:26,855 --> 00:52:28,334
You're very quiet there, Tom.

405
00:52:28,415 --> 00:52:31,327
Well, I was just thinking
we don't really want the ice to close up

406
00:52:31,415 --> 00:52:33,451
while we're underneath it.

407
00:52:34,615 --> 00:52:36,173
No, closing up would be a bad thing.

408
00:52:36,255 --> 00:52:37,244
-It would be a bummer.
-Yes.

409
00:52:38,055 --> 00:52:42,970
And Tom from Florida
was taking no chances against the cold.

410
00:52:43,815 --> 00:52:47,285
Ah, that feels really good.

411
00:52:50,055 --> 00:52:51,454
Sam, we gotta do this more often.

412
00:52:51,535 --> 00:52:52,854
Wha-hey!

413
00:53:03,935 --> 00:53:07,132
Now they were in the whales' realm.

414
00:53:09,175 --> 00:53:12,053
A vast underworld of frigid water

415
00:53:12,135 --> 00:53:15,013
enclosed beneath a ceiling of ice.

416
00:53:18,455 --> 00:53:21,049
This is a world we rarely see.

417
00:53:21,135 --> 00:53:25,128
Sinister, but at the same time
uniquely beautiful.

418
00:53:31,055 --> 00:53:33,888
As the melting ice runs into
the open cracks,

419
00:53:33,975 --> 00:53:36,205
it creates an underwater mirage

420
00:53:36,295 --> 00:53:41,130
as the layer of freshwater mixes with
the denser saltwater beneath it.

421
00:53:47,455 --> 00:53:51,653
If the ice were to close in on them now
they could get trapped.

422
00:53:53,655 --> 00:53:57,568
As they ventured deeper, the crew
carried a lifeline to the surface

423
00:53:57,655 --> 00:54:00,692
to guide them back
to their opening in the ice.

424
00:54:22,415 --> 00:54:25,487
Sadly, there were no narwhal to be seen,

425
00:54:25,575 --> 00:54:29,204
but it was a unique glimpse
of the whale's world.

426
00:54:29,895 --> 00:54:33,604
Sometimes it's a little bit spooky
to have a ceiling above your head,

427
00:54:33,695 --> 00:54:37,324
and then when the tank starts
breaking through a little bit

428
00:54:37,415 --> 00:54:38,609
once in a while you think,

429
00:54:38,695 --> 00:54:42,005
"Is this really an intelligent thing
to be doing?"

430
00:54:43,615 --> 00:54:46,493
But the shot looked cool,
so I think it was worth it.

431
00:54:48,935 --> 00:54:52,848
They had spent
over a month on and under the sea ice.

432
00:54:52,935 --> 00:54:57,645
But with still no shots of narwhal,
time and ice were running out.

433
00:54:59,655 --> 00:55:03,045
The edge of the ice was now
only 15 centimetres thick,

434
00:55:03,135 --> 00:55:07,765
barely enough to support the weight
of a man, let alone a camera team.

435
00:55:11,055 --> 00:55:15,207
You can feel the swell just coming up
underneath this ice, it's pretty trippy.

436
00:55:15,295 --> 00:55:18,048
It's just a gentle undulation
all around.

437
00:55:19,095 --> 00:55:20,972
This won't be here tomorrow.

438
00:55:25,335 --> 00:55:28,168
But just as
the ice was getting too thin,

439
00:55:28,255 --> 00:55:30,325
their effort was rewarded.

440
00:55:31,175 --> 00:55:34,167
-What do you see, Sam?
-Narwhal.

441
00:55:34,255 --> 00:55:38,134
See where the five guillemots are
out there on the water, six guillemots?

442
00:55:54,055 --> 00:55:56,933
Tom and his team had found the narwhal.

443
00:55:57,015 --> 00:55:59,768
The whales had arrived at long last.

444
00:55:59,855 --> 00:56:03,450
But sadly, the ice was now
too dangerous to film from.

445
00:56:05,495 --> 00:56:09,044
If they were to stand any chance
of continuing to film,

446
00:56:09,135 --> 00:56:12,366
it was time to call for reinforcements.

447
00:56:21,135 --> 00:56:24,366
After being stranded for seven days
due to bad weather,

448
00:56:24,455 --> 00:56:28,448
the helicopter crew
finally arrived, just in time.

449
00:56:31,495 --> 00:56:36,444
There was now one last chance
to film the narwhal, from the air.

450
00:56:37,455 --> 00:56:40,492
Armed with an advanced
aerial camera system,

451
00:56:40,575 --> 00:56:44,170
they could zoom in on the action
from a long distance away.

452
00:56:44,255 --> 00:56:46,564
This would enable them
to find the whales

453
00:56:46,655 --> 00:56:50,011
and even get close-up shots
without disturbing them.

454
00:56:54,935 --> 00:56:59,611
As the ice team headed home,
the helicopter team took over.

455
00:57:03,335 --> 00:57:07,294
The helicopter could only carry
enough fuel for a few hours' flying,

456
00:57:07,375 --> 00:57:11,653
and finding the whales in this
vast landscape was a daunting task.

457
00:57:13,375 --> 00:57:17,527
But at last they caught up
with the magical arctic unicorn.

458
00:57:18,375 --> 00:57:21,208
Yeah, there they are.
They're kind of 10 o'clock from me.

459
00:57:21,295 --> 00:57:22,933
Just coming under us now.

460
00:57:48,575 --> 00:57:51,612
Unaware of
the helicopter flying high above,

461
00:57:51,695 --> 00:57:55,051
the whales carried on
their journey through the ice.

462
00:57:57,455 --> 00:58:01,448
This is the first time the narwhal
migration has been filmed

463
00:58:01,535 --> 00:58:04,413
from this incredible aerial perspective.

464
00:58:12,455 --> 00:58:16,084
The plan had worked.
It had taken over six weeks,

465
00:58:16,175 --> 00:58:20,168
but the team had managed to film
the amazing journey of the narwhal

466
00:58:20,255 --> 00:58:24,043
in this most harsh
and testing of landscapes.

467
00:58:24,135 --> 00:58:26,695
It was a rare and magical insight

468
00:58:26,775 --> 00:58:31,485
into the life of one of our planet's
most mysterious creatures.

469
00:58:32,305 --> 00:58:38,212
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