Life in the Freezer (1993) s01e02 Episode Script

The Ice Retreats

It's September - early spring
in the southern hemisphere.
The Antarctic continent
is encircled by sea ice
that extends for hundreds
of miles northwards around its coasts
and encloses all but a few islands.
But these ice-free islands,
like South Georgia, are very precious,
for here the sea never freezes
and any sea animal that needs to
can always get ashore.
First to return each spring
are the bull elephant seals.
They are about to land on a breeding beach,
and each one knows that when he does
he will have to face rivals.
A full-grown male weighs over three tonnes.
Half the world's population
will come to this one island,
8,000 to this beach alone.
(LOUD BELLOWING)
This immense gathering of elephant seals
extends for some two miles up this beach.
It might seem to be totally disorganised,
but there is a pattern to it.
All these are females.
They came ashore about a month ago to pup
and now are ready to breed again.
And they all belong to this one male.
(THROATY BARKING)
This is a beachmaster
and there are a dozen or so like him
spaced out along this beach.
Each one of them has his own harem.
I estimate this one
has about a hundred females.
His sole object in life at the moment
is to make quite sure that he and he alone
mates with every one of them.
And for that he must fight
(AGGRESSIVE ROARING)
He's won,
but he'll have to battle many times
every day if he is to keep control.
The females gave birth
soon after they arrived.
They now have three weeks
in which to feed their pups
before they themselves
have to go back to sea to feed.
In that short time,
they have to transform a near empty bag of skin
into a full bag of blubber.
As they come to the end of suckling,
the females become sexually receptive again.
That is the moment the beachmaster
has been waiting for.
But while he is busy,
a rival is also busy
on the edge of the harem.
That can't be tolerated.
(ANGRY ROARING)
(DEEP ROAR)
A roar is enough -
the interloper retreats.
But many conflicts
will only be settled by violence.
Males get ripped -
and those in the way
of the fighters may get crushed.
(YELPING)
Every now and then, the beachmaster
proclaims his dominance with a roar.
The bigger the bull,
the louder and deeper his voice.
A rival can judge from it
whether or not he has a chance
in a straight battle.
(THROATY ROAR)
If he is going to persevere
with his challenge, he must now fight.
The pair rear up to over eight feet.
Their only weapons are their teeth,
but they can do a lot of damage with them.
The hide on the neck is particularly thick
and prevents serious injury.
A bout can go on for a quarter of an hour.
Eventually the battle is brought to an end
by exhaustion as much as anything else.
On the grassy slopes above the battleground,
the scene is more peaceful.
Black-browed albatross
are returning from the sea.
Grey-headed albatross are here too,
hanging on the updraughts
caused when the ever-continuing wind
is deflected upwards by the cliff face.
Throughout the past winter,
these birds have been flying alone
over the vast ocean,
searching for food.
Now they are returning to breed
and are assembling in colonies
several thousand strong.
(CAWING)
Breeding pairs from previous seasons
are reunited -
and each uses exactly
the same nest mound they used before.
But it does need a little renovation.
Mutual grooming renews
the bond between them.
Both grey-headed
and black-browed albatross
are faithful for life, twenty years or so,
and long-established pairs
only need a brief repetition of their
courtship ritual before they mate.
Two weeks later, the female lays a single egg,
and for the next seventy days,
the two take turns to incubate it.
While one keeps the egg warm,
the other flies off to feed
and may have to travel thousands of miles
before it gets what it needs.
Most kinds of albatross nest in colonies.
One special one, however,
prefers a more solitary life.
Light-mantled sooty albatross
are the last to return to the island.
The males come first.
One that is still unpaired settles on a ledge
and calls to passing females.
Having listened to many,
she eventually selects one.
The next stage in courtship
involves a certain amount
of nodding and dancing.
And then there follows a most beautiful
perfectly synchronised display flight.
During the day,
the skies belong to the albatross,
but as darkness comes,
other more nervous and more numerous birds
come to the island.
Thousands of small petrels and prions
fly agitatedly around the cliffs
in the darkness.
22 million nest amongst the tussac grass
on South Georgia alone.
Being so small, the prions are
vulnerable to attack by skuas,
and for the safety of their defenceless
chicks during the day,
they make their nests in burrows.
Outside, the white-chinned
petrels assemble.
(CONSTANT CHIRPING)
Duetting pairs defend the territories
around their burrows,
that can extend two metres
beneath the tussac grass.
The chick stays safely
inside the burrow for two months.
Every other day,
one of the adults comes to feed it
with a mixture of squid and krill.
Before dawn, and danger,
all the adults will have
disappeared from the island
and returned to the open ocean.
This hillside is jam-packed
with Macaroni penguins
and virtually nothing else.
There are some 80,000 of them here,
but even this vast assemblage
is only a tiny proportion
of the total population of South Georgia,
which is estimated
to be more than 10,000,000.
It's an astonishing
demonstration of the fact
that although the Antarctic
is virtually lifeless over vast areas,
there are one or two small oases
that teem with life.
After spending the winter
wandering around the northern fringes
of the southern ocean,
the Macaronis return
with remarkable punctuality.
In just ten days, the terraces of this
empty stadium become packed tight.
The males come first,
the females a week later.
The Macaroni is very much THE penguin
of the northern rim of the Antarctic.
Very few of them venture farther south
than the sub-Antarctic islands.
But here they constitute over fifty per cent
of all sea birds.
At the moment, at the beginning
of the breeding season,
they are squabbling noisily,
as each pair fights to hold
its own tiny nest site.
Each new arrival has to make its way
through a barrage of pecks
from outraged nest owners.
Macaronis must be the noisiest
and most bad-tempered of all penguins,
and sometimes the fights
can be really vicious.
(AGGRESSIVE SCREECHING)
Eventually, a female finds her male
and is rewarded with a greeting display
and a comforting preen.
Ten days later, she's produced two eggs.
But, remarkably, one of them -
the darker, smaller one -
is nearly always abandoned.
Why is not certain.
It may be insurance
against the loss of the bigger one.
But the colony is not littered
with abandoned eggs.
It has its own squad
of refuse collectors - sheathbills.
During the summer,
they normally eat penguin droppings.
An abandoned if addled egg
must make a nice change.
Sheathbills are one of the few birds here
that do not rely on the ocean
for food, at least directly.
They are totally land-based.
All the wildlife here in South Georgia -
the Macaroni penguins,
the albatrosses, the elephant seals,
even the tussac grass -
is virtually restricted
to the outer rim of Antarctica.
Farther south, it's a harsher world.
There, ice dominates.
But with the arrival of spring,
that world is warming just slightly.
The sea ice is retreating
and animals are returning -
animals that are specially adapted
to life in the frozen south.
Most of Antarctica
is still locked in by sea ice,
but as the days lengthen,
so that slowly retreats.
First to be freed
is the Antarctic peninsula,
a long arm of the continent
that reaches up northwards.
For a few months, it's possible
to reach its coast by sea.
Antarctica is nowhere lovelier.
But even at the height of the summer,
only 2% of the continent is free from ice,
and most of that is here.
But no sea animal will reach
those distant rock slopes
until the sea ice breaks up.
Gentoo penguins
are among the first to make it.
They need bare rock for their nests,
but even now that's so scarce
they may have a hard climb to reach it.
These are on their way to relieve their mates
who, for the past three days,
have been looking after the eggs.
Their eggs were laid in November,
almost a month after the Gentoos
up in South Georgia.
There's no soil here
with which to make a nest
and precious little vegetation,
just a few small stones.
And even the stones are in short supply
and may have to be
"borrowed" from a neighbour.
(ANNOYED SQUAWKING)
Nobody likes to see their nest
disappearing from beneath their feet.
But when thieves come from all sides,
there's not much you can do.
After five weeks of incubation,
the chicks start to hatch.
(FEEBLE SQUAWK)
Unlike the Macaronis,
both the Gentoos' eggs hatch.
For three weeks,
the adults care for the chicks,
protecting them from the cold.
They take turns to bring meals
of small fish and krill.
But the labour of doing so is enormous,
for there's that snow slope
to be traversed every time
and penguins were not designed for skiing.
As spring advances,
more and more of the peninsula
becomes ice-free,
and humpback whales
appear along the coast, seeking krill.
The sea ice, as it disintegrates,
forms a sort of soup of loose blocks.
This is the pack ice.
The whales will go no further.
(WHO0SH OF EXPELLED AIR)
At its outer edges,
the pack is easy to get through.
But further south, the floes become
bigger and more closely packed.
Only the most powerful ice-breaking
ships can force a passage
through the vast band of broken ice
that rings the continent.
In places, it's 200 miles across.
This, however, surprisingly,
is home of the most numerous large mammal
in the world apart from man -
crabeater seals.
Up to 30 million live around the continent
in this in-between world of ice and water.
Here they rest and pup.
They never come to land.
Despite their name, they live on krill.
They sieve sea water
through their interlocking teeth
and consume 20 kilos of it every day.
Even further south, beyond the pack ice,
there still remains
mile after mile of winter ice
that has not yet broken up.
Very few creatures can get
across this to the land beyond.
But one does
the Adelie penguin.
They breed further south
than any other penguin.
They can't wait for the ice
to break and have to walk.
In some years, they will march
for over 60 miles
to reach their traditional breeding grounds.
The Antarctic summer is short indeed.
They must hurry.
Their journey is remarkable enough
but, incredibly, one creature
makes an even longer one.
Snow petrels are smaller than pigeons,
yet they fly across ice that never melts
and climb to altitudes of 3,000 metres
right up and onto the vast Antarctic ice cap.
Here, over an area larger than Australia,
the ice is several miles thick.
It blankets whole mountain ranges.
Only the summits of the tallest
project through it,
as "nunataks".
These few tiny patches of rock
isolated in a sea of ice
are as precious as an oasis in a desert.
Only 2% of the continent is ice-free,
and nearly all of that is near the coast.
But snow petrels can't lay their eggs on ice
and are prepared to fly
a very long way to find bare rock.
One of their nests was found on a nunatak
like this, 144 miles from the coast.
Snow petrels bring life to this,
the most life-less part of our planet.
They breed further south than any other bird.
They have to wait
for their nesting ledges
to be cleared from the thick snow.
Even at the height of summer,
temperatures don't rise above minus 30.
There is no unfrozen water,
and to keep clean they have to bathe in snow.
As soon as the winds
have swept the bulk of the snow
from the higher rock slopes,
the snow petrels take possession of them.
But there is still much to do.
They may have to excavate a metre of snow
to get into a crevice
and find a nest site that suits them.
In the coming season,
they will have to make the journey
of over 200 miles back to open water
again and again
to collect food for their chicks.
But with their arrival,
spring has, at last, come to the deep south.
Next week, with the ice retreating
to its minimum extent,
we will watch the race to breed
as the wildlife takes advantage
of the brief Antarctic summer.
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