Life in the Freezer (1993) s01e01 Episode Script

I am at the very centre
of the great white continent,
Antarctica.
The South Pole is about half a mile away.
For a thousand miles in all directions
there is nothing but ice.
And, in the whole of this continent,
which is one and a half times
the size of the United States
and larger than Europe,
there is a year-round population
of no more than 800 people.
This is the loneliest
and the coldest place on Earth,
the place that is most hostile to life.
Yet, in one or two places,
it is astonishingly rich.
(HOWLING WIND)
Penguins come here by the million
and endure temperatures
of minus 70 degrees centigrade
and winds of 120 miles an hour.
Other birds fly right
to the heart of the continent,
even though they have to dig away snow
in order to find a place to nest.
And here is the nursery
for over half the world's seals.
Antarctica is remote
from all other continents,
surrounded by the vast southern ocean
and smothered by a blanket of ice
so immense that it contains
over 75% of the world's fresh water.
All life in the Antarctic
is dominated by the ice.
All but 2% of the continent is covered by it.
Its very whiteness
reflects back what little heat
there is in the sun's feeble rays,
and snow, when it falls,
remains permanently frozen,
so that now, after accumulating
for millions of years,
it has formed this gigantic ice cap
and the ice beneath my feet
is three miles thick.
Submerged beneath it
are mountain ranges as high as the Alps.
Only their summits project through it.
Rivers of ice spill down
from the ice cap as great glaciers
and creep slowly
towards the edge of the continent
and the sea.
When you get beneath the snout
of one of these huge glaciers,
you begin to appreciate
the immense power and size
of the Antarctic ice machine.
The ice here towers 100 feet above me
and the front of the glacier
is about two miles across.
But this is a small glacier.
The largest glacier
in Antarctica and in the world
is the Lambert glacier,
and that's 25 miles across.
This certainly is not a place to linger.
The glacier moves forward
at a rate of about two-thirds of a mile a year,
and the front end continually
breaks away to form icebergs.
If one came down now,
the surge could easily overturn a small boat.
These icefalls disintegrate into brash ice,
but when a large chunk of a glacier
or ice sheet breaks away,
it floats off as an iceberg.
At first, these bergs are slab-like,
but winds and waves above water
and currents below slowly carve them
into the loveliest of shapes.
A large berg can survive for up to ten years
before it ultimately breaks up and melts.
Only one fifth of an iceberg
is above the surface.
The rest is hidden beneath the water.
Streams of minute air bubbles,
released from the melting berg,
carve grooves in its submerged flanks.
Huge though bergs may be,
they are nonetheless usually on the move.
But come the winter,
sea ice forms around them
and locks them solid.
As winter progresses,
so more and more of the sea freezes,
spreading out from the margins
of the land like an immense skirt
so that, in effect,
the continent doubles in size.
When the ice reaches its farthest extent,
you have to travel hundreds of miles
from the edge of the continent
before you reach open water.
The annual formation of the sea ice
is the greatest seasonal change
that takes place on this planet,
and completely dominates
the lives of Antarctic animals.
Practically all of them depend
on the sea for their food,
so year-round access to it
is essential for their survival.
In the summer, when the sea ice melts,
they can reach the islands
that were trapped in the ice
and eventually the continent itself.
But when the ice re-forms,
they have to retreat north.
So now, in winter,
with the sea ice at its fullest extent,
it's in the sea that we must look for life.
The southern ocean is extremely rich in food.
Millions of penguins and seals
and thousands of whales feed here.
The majority of them rely
on just one source of food -
krill.
Krill are small, shrimp-like creatures
about six centimetres long.
In winter, they are dispersed widely,
mostly under the ice,
but in summer
they assemble in vast swarms,
some of which may contain
a billion individuals.
They are the most numerous animals on Earth.
Their total weight far exceeds
that of the total human population.
Humpback whales.
During the brief summer,
they gorge themselves on krill.
When the krill swarms are near the surface,
the humpbacks collect them by lunging.
They simply open their cavernous mouths
and scoop it up.
Often the whales co-operate,
working together as fishing boats do.
When the krill is more dispersed,
the whales have to dive deeper.
After a while,
lines of bubbles appear on the surface.
The bubbles gradually
form a pattern that spirals inwards.
Then suddenly, in its centre,
the whales appear.
Time and again, the pair dive.
When they reach the bottom of the dive,
they start releasing bubbles
and continue to do so as they swim upwards,
spiralling around one another.
These curtains of bubbles rise through the water,
creating a ring on the surface.
Underwater, the curtains drive
the krill into the centre of the spiral
and the humpbacks
then surge up through the middle,
jaws agape.
The humpbacks that visit Antarctica
only feed during the brief southern summer,
building their reserves
for a winter that will be spent
in less productive northern waters.
And so, for hour after hour
throughout the long Antarctic day,
these 40-tonne creatures
perform a splendidly synchronised
and very productive underwater ballet.
Other creatures benefit
from the whales' industry.
Sea birds forage in their wake.
As the whales drive the krill
closer to the surface,
it comes within reach of birds
that are not particularly skilled in diving.
Cape petrels, about the size of pigeons,
can only duck-dive a few feet down.
But that's enough to give them a share.
360 million sea birds constantly scour
the southern ocean for food.
They only go to land to breed.
Most of their lives are spent on the wing,
far out to sea.
This ocean is rich in nutrients
and very rough.
Howling gales whip it into huge waves.
These, with so few islands
to interrupt and break them,
grow and grow into some
of the most mountainous seas
to be found in any ocean.
Birds, dispersed over its vast surface,
face a huge problem in finding food,
for it is by no means
uniformly spread throughout the ocean.
The nutrients occur in patches,
and so the krill, which is
sustained by those nutrients,
is patchy too.
But once the birds find a swarm,
there is a frenzy of feeding.
Krill typically spends the day in deep water,
rising nearer to the surface at night.
But sometimes a swarm rises during the day
and then the birds get their chance.
But getting to the krill
is still a major problem
to all birds except penguins.
Albatrosses such as the black-browed,
whose diet is about 40% krill,
can only dive down
a couple of metres at the most.
Fur seals also feed out in the open ocean,
but they are able to dive
to 100 metres or more.
The patchiness of the krill
requires those that live on it
to spend a great deal of time searching,
and an albatross will fly hundreds,
sometimes thousands of miles,
on a single foraging trip.
Out here, birds can't afford to be fussy,
and must take whatever food they can find.
Almost all of them scavenge to some extent.
These birds have found
the remains of a small whale.
They are the crumbs left behind
after a catch by killer whales.
Giant petrels -
the vultures of the Antarctic -
soon dominate the feast.
(SCREECHING)
The biggest of all these scavengers
is the wandering albatross.
With a wing-span of over three metres,
this bird can range over greater
distances than any other.
It needs the updraught
created by waves in order to fly,
and only these stormy southern waters
provide that in such abundance.
Throughout the winter, the wandering
albatross remain in the south,
for although the continent is trapped in ice,
there are a few outer islands
that always remain beyond its grasp,
and these provide the albatross
with their nesting sites.
3,000 pairs of wandering albatross
nest on one of them,
here in South Georgia.
An adult wanderer may travel 5,000 miles -
sometimes to Brazil and back -
in order to collect squid for its young.
This enormous chick weighs ten kilos,
as much as a full-grown swan.
It's the biggest of any sea bird chick.
Although it's a couple of months
before it has to face its first flight,
it's now at its maximum weight.
In fact, it's heavier even
(HE LAUGHS)
heavier than the adult.
The spring snows are now beginning to melt,
but the chick has already faced
the worst of the winter weather.
Hatched last March,
it has sat here on its nest mound
unprotected and unshielded for eight months
while the temperatures may have
fallen to minus 10 degrees
and terrible storms raged.
It's so big that it can't possibly
grow to this very huge size
in the short summer season.
So the parents have to come to feed it
every three or four days for 10 months.
In order to do that,
they have to be able to reach the open sea.
Only one other animal breeds
throughout the year on the outer islands -
King penguins.
They also need continuous access to the ocean
to collect food for their chicks.
Throughout the winter,
adults come and go from their
traditional breeding colonies.
(DIN OF SQUAWKING)
Antarctica is home to two million Kings.
In this one colony alone,
there are 600,000 of them.
These engaging chicks are so inquisitive
that you only have
to sit down to their own level
for them all to gather round you
and try and discover
what sort of creature you are.
They were hatched last summer
and, like the albatross chicks,
they're coming to the end
of their first winter.
During that period, their parents
were out to sea catching food for them,
but each chick was only fed
about once every three weeks.
Left to themselves for so long,
they've all gathered together
This one contains about 50,000 chicks.
You might think that this huge congregation
would make it almost impossible
for a parent returning with food
to find its own chick.
Not so - the fact is that parent and chick
can recognise one another's voice.
(DIN OF CALLS AND WHISTLES)
A returning adult may spend hours
looking for its chick among such a crowd,
for the young are inclined to wander.
The chick will respond to its parent's call
and the parent to the chick's whistle.
Eventually they meet
(CHICK WHISTLES VERY LOUDLY)
but instead of feeding
the chick straight away,
the adult leads it through the rookery,
as if to test the bond between them.
At last, in response
to its chick's plaintive entreaties,
the parent regurgitates a meal of squid.
A King penguin chick
takes more than 12 months to rear,
so the adults can't breed annually.
At best, they raise two chicks
every three years.
Because of this,
the breeding cycle of any one pair
slides out of phase with the seasons.
So now, late in winter,
there are chicks both young and old
and adults at different stages in their cycle.
Some of the adults are going
through their pre-breeding moult
before going to sea
to fatten up for courtship.
Others are already courting,
parading back and forth
with a special ritualised walk.
The male usually leads.
If the female is sufficiently impressed,
the pair seal their relationship
with a vocal duet.
(MALE AND FEMALE
TAKE IT IN TURNS TO CALL)
King penguin rookeries are very busy places.
Every morning at about six o'clock,
the adults leave their chicks,
cross the glacier stream
and march down to the sea.
They like to take an early morning bath,
getting rid of the smelly mud
and grime of the crowded colony.
For an hour or so,
they wash in the surf.
These penguins seem to have
a fairly easy time of it,
surrounded by an ocean laden with food
and with year-round access
to their breeding beaches.
But they are one of the few
of Antarctica's inhabitants
to achieve independence from the factor
that governs almost everything else -
the advance and retreat of the sea ice.
King penguin and albatross live only
on the frontier of the Antarctic.
They never go closer to the pole
than the edge of the sea ice.
Next week, we will.
As spring really takes hold,
we will follow the retreating sea ice
to the shores of the continent
and go up to the great ice cap,
to the very heart of the Antarctic,
where life in the freezer
faces its greatest challenge.