BBC Life in the Freezer 02 The Ice Retreats
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00:40It's September, early spring in the Southern Hemisphere.
00:47The Antarctic continent is encircled by sea ice
00:50that extends for hundreds of miles northwards around its coasts
00:54and encloses all but a few islands.
01:00But these ice-free islands, like South Georgia, are very precious,
01:04for here the sea never freezes,
01:06and any sea animal that needs to can always get ashore.
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01:45First to return each spring are the boar elephant seals.
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01:59They are about to land on a breeding beach,
02:02and each one knows that when he does, he will have to face rivals.
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02:10A full-grown male weighs over three tons.
02:16Half the world's population will come to this one island,
02:198,000 to this beach alone.
02:24This immense gathering of elephant seals
02:27extends for some two miles up this beach.
02:30At first sight, it might seem to be totally disorganized,
02:33but in fact, there's a pattern to it.
02:36All these are females.
02:39They came ashore about a month ago to pup,
02:43and now they're ready to breed again,
02:46and they all belong to this one male.
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02:56This is a beach master,
02:59and there are a dozen or so like him spaced out along this beach.
03:04Each one of them has his own harem,
03:07and I estimate that this one has about 100 females in his,
03:12and his sole object in life at the moment
03:15is to make quite sure that he and he alone
03:18mates with every single one of them.
03:20And to that, he must fight.
03:43He's one, but he'll have to battle many times every day
03:47if he is to keep control.
03:51The females gave birth soon after they arrived.
03:55They now have three weeks in which to feed their pups
03:58before they themselves have to go back to sea to feed.
04:05In that short time, they have to transform
04:08a near-empty bag of skin into a full bag of blubber.
04:16As they come to the end of suckling,
04:19the females become sexually receptive again.
04:22That is the moment that the beach master has been waiting for.
04:32But while he is busy,
04:34a rival is also busy on the edge of the harem.
04:39And that can't be tolerated.
04:50A roar is enough.
04:52The interloper retreats.
04:58But many conflicts will only be settled by violence.
05:02Males get ripped, and those that get in the way of the fighters
05:06are likely to get crushed.
05:10The fight is over.
05:12The fight is over.
05:14The fight is over.
05:16But the fighters are likely to get crushed.
05:27Every now and then, the beach master proclaims his dominance with a roar.
05:32The bigger the bull, the louder and deeper his voice.
05:35A rival can judge from it
05:37whether or not he has a chance in a straight battle.
05:47If he's going to persevere with his challenge,
05:50he must now fight.
05:56The pair rear up to over eight feet.
05:59Their only weapons are their teeth,
06:01but they can do a lot of damage with them.
06:17The fight is over.
06:33The hide on the neck is particularly thick and prevents serious injury.
06:38A bout can go on for a quarter of an hour.
06:41Eventually, the battle is brought to an end
06:44by exhaustion as much as anything else.
06:56On the grassy slopes above the battleground,
06:59the scene is more peaceful.
07:02Black-browed albatross are returning from the sea.
07:15MUSIC
07:30Grey-headed albatross are here too,
07:33hanging on the updrafts caused when the ever-continuing wind
07:37is deflected upwards by the cliff face.
07:45MUSIC
07:52Throughout the past winter,
07:54these birds have been flying alone over the vast ocean,
07:57searching for food.
07:59But now they're returning to breed
08:01and are assembling in colonies several thousand strong.
08:06BIRD CALLS
08:10Breeding pairs from previous seasons are reunited,
08:14and each uses exactly the same nest mound as they used before.
08:19But it does need a bit of renovation.
08:28Mutual grooming renews the bond between them.
08:36BIRD CALLS
08:39Both grey-headed and black-browed albatross are faithful for life,
08:4320 years or so,
08:45and long-established pairs only need a brief repetition
08:48of their courtship ritual before they mate.
08:51BIRD CALLS
09:06Two weeks later, the female lays a single egg,
09:10and for the next 70 days, the two take turns to incubate it.
09:25While one keeps the egg warm, the other flies off to feed
09:30and may have to travel thousands of miles before it gets what it needs.
09:36BIRD CALLS
09:38Most kinds of albatross nest in colonies.
09:41One special one, however, prefers a more solitary life.
09:49Light-mantled sooty albatross are the last to return to the island.
09:54The males come first.
10:01BIRD CALLS
10:03One that is still unpaired settles on a ledge and calls to passing females.
10:09BIRD CALLS
10:18BIRD CALLS
10:21BIRD CALLS
10:27Having listened to many, she eventually selects one.
10:33BIRD CALLS
10:37The next stage in courtship involves a certain amount of nodding and dancing.
10:49And then there follows a most beautiful, perfectly synchronised display flight.
11:03BIRD CALLS
11:34BIRD CALLS
11:48During the day, the skies belong to the albatross,
11:52but as darkness comes, other more nervous and more numerous birds come to the island.
12:00BIRD CALLS
12:04BIRD CALLS
12:06Thousands of small petrels and prions fly agitatedly around the cliffs in the darkness.
12:15Twenty-two million nest among the tussock grass on the island of South Georgia alone.
12:24Being so small, the prions are vulnerable to attack by skewers,
12:28and for the safety of the defenceless chicks during the day, they make their nest in burrows.
12:35Outside, the white-chinned petrels assemble.
12:45Dueting pairs defend the territories around their burrows that can extend two metres beneath the tussock grass.
12:58The chick stays safely inside the burrow for two months.
13:02Every other day, one of the adults comes to feed it with a mixture of squid and krill.
13:12Before dawn and danger, all the adults will have disappeared from the island and returned to the open ocean.
13:19MUSIC
13:26This hillside is jam-packed with macaroni penguins and virtually nothing else.
13:32There are some 80,000 of them here,
13:35but even this vast assemblage is only a tiny proportion of the total population of South Georgia,
13:42which is estimated to be more than 10 million.
13:46It's an astonishing demonstration of the fact that although the Antarctic is virtually lifeless over vast areas,
13:53there are one or two small oases that teem with life.
14:07After spending the winter wandering around the northern fringes of the Southern Ocean,
14:11the macaronis return with remarkable punctuality.
14:15In just ten days, the terraces of this empty stadium become packed tight.
14:21The males come first, the females a week later.
14:29The macaroni is very much the penguin of the northern rim of the Antarctic.
14:35Very few of them venture farther south than these sub-Antarctic islands,
14:40but here they constitute over 50% of all the seabirds.
14:46At the moment, at the beginning of the breeding season,
14:49they're squabbling noisily as each pair fights to hold its own tiny nest site.
14:58Each new arrival has to make its way through a barrage of pecks from outraged nest owners.
15:05Macaronis must be the noisiest and most bad-tempered of all penguins,
15:10and sometimes the fights can be really vicious.
15:34Eventually, a female finds her male and is rewarded with a greeting display...
15:44...and a comforting preen.
15:51The macaroni is the first of its kind,
15:54and it's the only one of its kind in the world.
15:58...and a comforting preen.
16:10Ten days later, she's produced two eggs,
16:14but remarkably, one of them, the darker, smaller one, is nearly always abandoned.
16:19Why is not certain.
16:21It may perhaps be an insurance against the loss of the bigger one.
16:26But the colony is not littered with abandoned eggs.
16:29It has its own squad of refuse collectors, sheathbills.
16:41During the summer, they normally eat penguin droppings.
16:45An abandoned, if addled, egg must make a nice change.
16:51Sheathbills are one of the few birds here that do not rely on the ocean for food,
16:55at least directly.
16:57They are totally land-based.
17:01All the wildlife here in South Georgia,
17:04the macaroni penguins, the albatrosses, the elephant seals,
17:08even the tussock grass, is virtually restricted to the outer rim of Antarctica.
17:13Farther south, it's a harsher world.
17:16There, ice dominates.
17:19But with the arrival of spring, that world is warming just slightly.
17:23The sea ice is retreating, and animals are returning,
17:26animals that are specially adapted to life in the frozen south.
17:35Most of Antarctica is still locked in by sea ice.
17:39But as the days lengthen, so that slowly retreats.
17:43First to be freed is the Antarctic Peninsula,
17:47a long arm of the continent that reaches up northwards.
17:54For a few months, it's possible to reach its coast by sea.
17:59Antarctica is nowhere lovelier.
18:04But even at the height of the summer,
18:06only 2% of the continent is free from ice,
18:09and most of that is here.
18:24But no sea animals will reach those distant rock slopes
18:28until the sea ice breaks up.
18:46Gentoo penguins are among the first to make it.
18:51They need bare rock for their nests,
18:54but even now, it's so scarce, they may have a hard climb to reach it.
19:04These are on their way to relieve their mates,
19:07who, for the past three days, have been looking after the eggs.
19:12Their eggs were laid in November,
19:14almost a month after the gentoos up in south Georgia.
19:17There's no soil here with which to make a nest,
19:20and precious little vegetation, just a few small stones.
19:31The gentoo penguins have been looking for their mates
19:34for the past three days.
19:38And even the stones are in short supply
19:41and may have to be borrowed from a neighbour.
20:08Nobody likes to see their nests disappearing from beneath their feet.
20:15But when thieves come from all sides,
20:18there's not much you can do about it.
20:27After five weeks of incubation, the chicks start to hatch.
20:38Unlike the macaronis, both the gentoo's eggs hatch.
20:42For three weeks, the adults care for the chicks,
20:45protecting them from the cold.
20:47They take turns to bring meals of small fish and krill.
20:54But the labour of doing so is enormous,
20:57for there's that snow slope to be traversed every time,
21:01and penguins were not designed for skiing.
21:07MUSIC
21:38MUSIC
21:43As spring advances, more and more of the peninsula becomes ice-free,
21:47and humpback whales appear along the coast seeking krill.
22:02The sea ice, as it disintegrates,
22:04forms a sort of soup of loose blocks.
22:07This is the pack ice.
22:09The whales will go no further.
22:25At its outer edges, the pack is easy to get through,
22:28but as you go further south,
22:30the flows become bigger and more closely packed.
22:34MUSIC
22:47Only the most powerful ice-breaking ships can force a passage
22:51through the vast band of broken ice that rings the continent.
22:54In places, it's 200 miles across.
22:57This, however, surprisingly,
22:59is home of the most numerous large mammal in the world,
23:02apart from man.
23:06Crab-eater seals.
23:08Up to 30 million live around the continent
23:10in this in-between world of ice and water.
23:13Here they rest and here they pup.
23:15They never come to land.
23:19Despite their name, they live on krill.
23:22They sieve seawater through their interlocking teeth
23:25and consume 20 kilos of it every day.
23:29MUSIC
23:50Even farther south, beyond the pack ice,
23:53there still remains mile after mile of winter ice
23:57that has not yet broken up.
24:00Very few creatures can get across this to the land beyond,
24:04but one does.
24:11The Adelie penguin.
24:13They breed farther south than any other penguin.
24:17They can't wait for the ice to break and have to walk.
24:21In some years, they will march for over 60 miles
24:24to reach their traditional breeding grounds.
24:28The Antarctic summer is short indeed.
24:31They must hurry.
24:33MUSIC
24:58MUSIC
25:03Their journey is remarkable enough,
25:06but incredibly, one creature makes an even longer one.
25:12Snow petrels are smaller than pigeons,
25:15yet they fly across ice that never melts
25:18and climb to altitudes of 3,000 meters
25:22right up and onto the vast Antarctic ice cap.
25:28Here, over an area larger than Australia,
25:32the ice is several miles thick.
25:34It blankets whole mountain ranges.
25:37Only the summits of the tallest project through it as nonatacs.
25:46These few tiny patches of rock, isolated in the sea of ice,
25:51are as precious as an oasis in a desert.
25:54Only 2% of the continent is ice-free
25:57and nearly all of that is near the coast.
26:00But snow petrels, like nearly all Antarctic birds,
26:03can't lay their eggs on ice
26:05and they're prepared to fly a very long way to find bare rock.
26:09One of their nests was found on a nonatac like this,
26:12144 miles from the coast.
26:16Snow petrels bring life to this,
26:19the most lifeless part of our planet.
26:30They breed farther south than any other bird.
26:33They have to wait for their nesting ledges to be cleared from the thick snow.
26:37Even at the height of summer,
26:39temperatures don't rise above minus 30 degrees.
26:42There is no unfrozen water
26:44and to keep themselves clean, they have to bathe in snow.
27:43As soon as the winds have swept the bulk of the snow
27:46from the higher rock slopes,
27:48the snow petrels take possession of them.
27:51But even then, there is much to do.
27:53They may have to excavate a metre of snow
27:56to get into a crevice and find a nest site that suits them.
28:00In the coming season, they will have to make the journey
28:03of over 200 miles back to open water
28:06again and again to collect food for their chicks.
28:13But with their arrival, spring has at last come.
28:17The snow petrels are ready to go back to their nests.
28:21They have to wait for the winter to come
28:24before they can go back to their nests.
28:27With their arrival, spring has at last come to the deep south.
28:34Next week, with the ice retreating to its minimum extent,
28:38we will watch the race to breed
28:40as the wildlife takes advantage of the brief Antarctic summer.
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