BBC Life in the Freezer 04 The Door Closes
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01:10The pounding surf of the Great Southern Ocean,
01:13beating on the rocks of South Georgia.
01:16Few creatures you might think could survive it,
01:19but Macaroni penguins are desperate to get ashore.
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01:34Their flippers are a little help out of water.
01:37All they have to give them a grip on these slippery rocks
01:41are the small claws on their feet.
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02:01Now, at the end of summer,
02:03life is becoming increasingly difficult
02:06for these Macaroni penguins,
02:08who are struggling to feed their chicks
02:10when they are almost fully grown and have massive appetites.
02:14With the approach of autumn, the weather will worsen.
02:18Massive depressions rush around the fringes
02:21of the Antarctic continent, creating huge gales
02:24that gust to over 100 miles an hour
02:27and lash the sea into a frenzy.
02:30Before long, the temperatures will drop to below freezing,
02:33and then all the wildlife of Antarctica
02:36will be engaged in a desperate race
02:38to complete breeding before the ice closes everything down.
02:47In the deep south, the sea has stayed frozen all summer.
02:51The penguins here face an even greater challenge,
02:55for this is where the door closes first.
02:58Here at Cape Roids, I'm 1,400 miles closer to the pole,
03:03and this, a daily colony,
03:05is the most southerly nesting group of any penguins anywhere.
03:09The summer here is very short indeed,
03:12and these penguins have to breed very swiftly
03:15if they're to be successful.
03:17They're well ahead of the Macaronis up in the north,
03:20and the chicks are already losing their down.
03:25Beneath the woolly coat lies the waterproof layer of feathers
03:29that will protect them in the icy southern seas.
03:33The season is so short that things have to move fast.
03:38Over a mere two weeks, the jam-packed colony virtually empties
03:43as the newly feathered young follow their parents down to the sea
03:47to make their first encounter with water.
03:51And their first swim will not be easy.
03:54The bay is filled with surging, sharp-edged brash ice.
04:00Even getting down to the water,
04:02the penguins have a hard time getting to the bottom of the water.
04:06It's not easy.
04:08It's not easy.
04:10It's not easy.
04:12It's not easy.
04:14It's not easy.
04:16It's not easy.
04:18Even getting down to the water poses problems.
04:26Soon, the edge of the sea is thronged by apprehensive youngsters
04:30nervously waiting for someone to take the plunge.
04:38The brash is so thick and extensive that on its seaward side,
04:42adults returning with food for their chicks can't get through.
04:48They turn back.
04:58The hungry youngsters now have little alternative.
05:01They have to get to sea to feed them.
05:05In fact, it's easier for them to cross the brash than for their parents.
05:09Being significantly lighter and more buoyant,
05:12they can skitter across the surface of the broken ice.
05:20The penguins have to get to the bottom of the water
05:23to make their first encounter with water.
05:26It's not easy.
05:28It's not easy.
05:30It's not easy.
05:33It's not easy.
05:43But moving so slowly and so clumsily puts them in real danger.
05:49Ah!
05:58A leopard seal.
06:11The majority of the chicks make it to open water,
06:15where they're a little safer.
06:17The leopard seal stays with its victim.
06:47Ah!
06:49Ah!
06:52Ah!
07:15This game of cat and mouse goes on for 20 minutes.
07:19Like so many other large predators on land and on sea,
07:23the leopard seal seems to feel no urgency to complete its kill.
07:32At last, the penguin is dead.
07:37Now the process of stripping off its flesh begins.
07:49Ah!
08:12The carcass drifts down to the sea floor,
08:16but it won't be wasted.
08:19Ah!
08:36A nematine worm, a metre long.
08:39It has detected the taste of penguin flesh
08:42drifting through the cold water.
08:50Ah!
08:54Another scavenger arrives, a giant isopod, ten centimetres long,
08:59the equivalent of crabs in warmer waters.
09:11The isopod strips off the meat with its hooked legs and strong jaws.
09:16The worm just turns its stomach inside out and envelops the food.
09:23Within hours, the carcass is covered by a writhing tangle of worms.
09:32Within days, there is nothing left but bare bones.
09:40The first snows of winter have fallen.
09:44The last chicks to hatch are doomed.
09:47Their parents have to abandon them before they're fully grown.
09:52The adults must go to sea to build up their strength
09:55before returning to the colony for one last ordeal
09:58before winter sets in, the molt.
10:02All penguins need a new coat of feathers for the winter
10:05and that means shedding the old one.
10:07And colonies right around the continent fill with shed feathers.
10:14On Deception Island, chinstrap penguins stand silent and motionless.
10:27Only a month ago, these steep slopes of volcanic ash
10:31were noisy with the squawks of 80,000 pairs of them
10:35coming and going and caring for their chicks.
10:38Now, the penguins have little energy to spare.
10:41They can't go to sea with their coats in this condition, so they can't feed.
10:53For three weeks, they stand fasting, losing half their body weight.
10:57But at the end, they will have warm, watertight coats
11:01and be ready for the icy blasts of winter.
11:05By the end of March, most of them have left
11:08and the remainder are on the move,
11:10making their way across the emptying slopes back to the sea.
11:15By the end of March, most of them have left
11:18and the remainder are on the move,
11:20making their way across the emptying slopes back to the sea.
11:45Escape to the north to open sea is the driving force
11:50to move where the food should be.
11:53But the obstacles are formidable.
12:15At minus 1.9 degrees centigrade, the sea begins to freeze.
12:20At minus 1.9 degrees centigrade, the sea begins to freeze.
12:23A slight swell on the surface produces pancake ice.
12:35In the frigid air, the ice above water grows into crystals.
12:40The early explorers called these fantastic shapes ice flowers.
12:54As it gets colder and colder, the ice thickens.
12:58On the coast, it freezes fast to the margins of the land.
13:02Farther out, the pancake ice consolidates into sea ice.
13:09The belt of ice surrounding the continent widens,
13:12advancing northwards two miles a day and driving life before it.
13:20But the ice front has not yet reached all the islands
13:23and there are still some that remain.
13:27But the ice front has not yet reached all the islands
13:30and there are still some that can provide a refuge for wildlife well into autumn.
13:44Here on South Georgia, we're on the northern edge of Antarctica.
13:49You can be fairly sure that the sea here won't freeze over.
13:53Only once or twice in a century does it do so.
13:56This floating ice has all fallen from the glacier behind me.
14:01But although at 54 degrees south,
14:04we are as far away from the South Pole as Britain is from the north,
14:08the immense ice cap of Antarctica still dominates the climate.
14:15Glaciers cover over half the island.
14:18They blanket many of the peaks, the tallest of which are 2,700 metres high.
14:24And in some places, they run right down into the sea.
14:28During the winter, the temperature falls to minus 10 degrees at the coast.
14:33So the need for animals to complete their breeding in the short summer season
14:37is still very intense.
14:43Two million fur seals come here to breed
14:46and at the end of summer, the beaches are thronged with young pups and their mothers.
14:54The pups suckle for four months until late March.
14:58That's longer than the fur seals that live in warmer waters farther north.
15:02It's a measure of how strong young animals have to be if they're to survive down here.
15:08A pup, if it is to get all the milk that is its due,
15:12has to recognise its mother's call when she returns from feeding at sea
15:16and is ready to provide a feed.
15:38Three months earlier, this shore was a battlefield
15:41as the bulls fought for the right to dominate a stretch of beach
15:45and all the females on it.
15:47Now the mating is finished and the bulls have gone to sea,
15:50only the pups are left, testing their strength with mock fights.
16:38BIRDS CHIRP
16:51Many of the youngsters playing here will not survive their first year.
16:56The weaker ones will not get enough food.
16:58There will be accidents, there will be orphans.
17:02By the end of the breeding season, corpses lie scattered over the beach,
17:06food for the skewers and the giant petrels.
17:09BIRDS CHIRP
17:40The petrels, with their great hooked beaks,
17:43are usually the first to rip open a carcass.
17:48They are the Antarctic's equivalent of Africa's vultures.
17:52Their huge wings are two metres across,
17:55but unlike vultures, they don't just scavenge.
17:58They will tackle young penguins and small seabirds while they're still alive.
18:10WHALE SOUNDS
18:34The whalers in the old days used to call them gluttons.
18:38It's easy to see why,
18:40and their dirtiness gave them another name, too, stinkers.
18:46Surprisingly, there are ducks at this feast, too.
18:50These are the South Georgia pintails.
18:52Alone among ducks, they've acquired a regular taste for meat.
18:57WHALE SOUNDS
19:09DUCKS QUACK
19:35An elephant seal wallow.
19:38This is an all-female gathering.
19:40They clearly like one another's company,
19:42for they congregate in great assemblies.
19:44But that doesn't mean that they don't, on occasion,
19:47get irritated with one another.
20:00Like the penguins, they went to sea after rearing their young,
20:04fed intensively to put on the weight they lost during breeding,
20:07and now they've come back in order to molt.
20:15Large chunks of skin and hair peel off their bodies,
20:19and it seems to make them very tetchy.
20:24It takes a month for them to grow new coats.
20:27Then, as the temperature falls still lower and winter closes in,
20:31they will return to the place where they're most at home, the sea.
20:38WHALE SOUNDS
20:41Grey-headed albatross also nest on South Georgia,
20:45but they stay a little longer.
20:51The waters are still ice-free,
20:53so they can catch food for their young well into autumn.
21:01WHALE SOUNDS
21:08CHICKEN SQUAWKS
21:17An adult bird caring for its chick may travel 600 miles or more to find food,
21:23which it brings back in its crop.
21:37That was a squid, and very nice too.
21:44Above the greyheads, another kind of albatross,
21:47the largest seabird in the world with a three-metre wingspan,
21:51the wandering albatross.
21:55It nests a little further inland
21:57on South Georgia's meadows and ridges of tussock grass.
22:08In marked contrast to the other birds that have almost finished their breeding
22:12and are preparing to leave,
22:14this wandering albatross has come to start a courtship
22:17that may take two or three years.
22:21WHALE SOUNDS
22:33These young birds have spent the first three years of their adult life at sea.
22:38Now they've returned to the colony where they were reared
22:41and are starting to look for a partner,
22:43and the way they do this is by taking part in dancing parties.
22:50WHALE SOUNDS
22:54WHALE SOUNDS
23:06WHALE SOUNDS
23:16Young unmated birds court like this for several years
23:20before they decide who their partner shall be
23:23and together start work on a nest mound.
23:40But as the winter sets in and its icy door closes,
23:44the young albatross too have to return to sea.
23:50WHALE SOUNDS
24:20The sea won't freeze here around South Georgia,
24:23but as the sun moves north and the days darken,
24:27the temperature of the ocean falls lower still
24:30and life in the water becomes increasingly scarce.
24:34The huge shoals of krill disperse and for the seabirds,
24:38food becomes more and more difficult to find.
24:41WHALE SOUNDS
24:51By April, winter storms are beginning to sweep across the Antarctic.
24:56WHALE SOUNDS
25:21The winds rise to above 100 miles an hour.
25:25The temperature falls to 70 degrees below zero.
25:34And then the sea freezes.
25:37The door has shut.
25:42Throughout the winter, the ice continues to advance northwards.
25:46The area it covers increases at the rate of 40,000 square miles every day.
25:52Before the winter is over,
25:54it will have almost doubled the size of the continent.
26:16WHALE SOUNDS
26:31Now, at the end of autumn,
26:33practically all the wildlife has escaped to the north.
26:37The whales have gone to find warmer waters in which to breed.
26:41The seals, the albatrosses and most of the penguins
26:44have also gone out to sea,
26:46though no-one as yet is sure exactly where.
26:49But there is one truly remarkable creature
26:52that seems to turn all these rules upside down.
26:55The emperor penguin.
26:59Largest of all the penguins, the emperor stands over a metre high
27:04and weighs, on average, 33 kilos.
27:07Most creatures are forced by the worsening weather
27:10to retreat north to warmer latitudes,
27:12but the emperors are gathering at the ice edge
27:15to start travelling into the deep south,
27:18where they will mate and rear their young.
27:42WHALE SOUNDS
28:05Now the emperors start their long march,
28:08maybe tens of miles,
28:10to reach their traditional nesting site on the sea ice.
28:14In the next programme, we'll follow them
28:17and see, with temperatures dropping to minus 70 degrees centigrade,
28:22how life in the freezer faces the ultimate challenge,
28:27the Antarctic winter.
28:38BELLS CHIMING