{1}{1}25.000
{1195}{1251}I am at the very centre
{1253}{1310}of the great white continent,
{1312}{1352}Antarctica.
{1354}{1435}The South Pole is about half a mile away.
{1439}{1517}For a thousand miles in all directions
{1519}{1571}there is nothing but ice.
{1585}{1643}And, in the whole of this continent,
{1645}{1764}which is one and a half times|the size of the United States
{1766}{1816}and larger than Europe,
{1818}{1878}there is a year-round population
{1880}{1951}of no more than 800 people.
{1976}{2092}This is the loneliest|and the coldest place on Earth,
{2094}{2185}the place that is most hostile to life.
{2210}{2268}Yet, in one or two places,
{2270}{2328}it is astonishingly rich.
{2355}{2406}(H0WLING WIND)
{2661}{2724}Penguins come here by the million
{2726}{2773}and endure temperatures
{2778}{2907}of minus 70 degrees centigrade|and winds of 120 miles an hour.
{3165}{3254}0ther birds fly right|to the heart of the continent,
{3256}{3362}even though they have to dig away snow|in order to find a place to nest.
{3366}{3489}And here is the nursery|for over half the world's seals.
{3584}{3669}Antarctica is remote|from all other continents,
{3671}{3735}surrounded by the vast southern ocean
{3737}{3801}and smothered by a blanket of ice
{3803}{3932}so immense that it contains|over 75% of the world's fresh water.
{3944}{3993}All life in the Antarctic
{3995}{4049}is dominated by the ice.
{4051}{4155}All but 2% of the continent is covered by it.
{4157}{4206}Its very whiteness
{4208}{4317}reflects back what little heat|there is in the sun's feeble rays,
{4319}{4398}and snow, when it falls,|remains permanently frozen,
{4400}{4504}so that now, after accumulating|for millions of years,
{4506}{4575}it has formed this gigantic ice cap
{4577}{4663}and the ice beneath my feet|is three miles thick.
{4706}{4817}Submerged beneath it|are mountain ranges as high as the Alps.
{4832}{4892}0nly their summits project through it.
{5090}{5206}Rivers of ice spill down|from the ice cap as great glaciers
{5210}{5282}and creep slowly|towards the edge of the continent
{5284}{5332}and the sea.
{5417}{5518}When you get beneath the snout|of one of these huge glaciers,
{5520}{5571}you begin to appreciate
{5573}{5692}the immense power and size|of the Antarctic ice machine.
{5694}{5784}The ice here towers 100 feet above me
{5786}{5897}and the front of the glacier|is about two miles across.
{5899}{5954}But this is a small glacier.
{5956}{6034}The largest glacier|in Antarctica and in the world
{6036}{6147}is the Lambert glacier,|and that's 25 miles across.
{6149}{6231}This certainly is not a place to linger.
{6233}{6281}The glacier moves forward
{6283}{6350}at a rate of about two-thirds of a mile a year,
{6352}{6464}and the front end continually|breaks away to form icebergs.
{6466}{6513}If one came down now,
{6515}{6601}the surge could easily overturn a small boat.
{7762}{7866}These icefalls disintegrate into brash ice,
{7868}{7984}but when a large chunk of a glacier|or ice sheet breaks away,
{7986}{8038}it floats off as an iceberg.
{8091}{8165}At first, these bergs are slab-like,
{8167}{8292}but winds and waves above water|and currents below slowly carve them
{8296}{8355}into the loveliest of shapes.
{8646}{8736}A large berg can survive for up to ten years
{8738}{8823}before it ultimately breaks up and melts.
{8915}{9035}0nly one fifth of an iceberg|is above the surface.
{9037}{9091}The rest is hidden beneath the water.
{9448}{9558}Streams of minute air bubbles,|released from the melting berg,
{9560}{9641}carve grooves in its submerged flanks.
{9693}{9746}Huge though bergs may be,
{9748}{9822}they are nonetheless usually on the move.
{10171}{10205}But come the winter,
{10207}{10258}sea ice forms around them
{10260}{10309}and locks them solid.
{10517}{10635}As winter progresses,|so more and more of the sea freezes,
{10637}{10742}spreading out from the margins|of the land like an immense skirt
{10744}{10842}so that, in effect,|the continent doubles in size.
{10844}{10904}When the ice reaches its farthest extent,
{10906}{11000}you have to travel hundreds of miles|from the edge of the continent
{11002}{11054}before you reach open water.
{11084}{11161}The annual formation of the sea ice
{11163}{11264}is the greatest seasonal change|that takes place on this planet,
{11266}{11357}and completely dominates|the lives of Antarctic animals.
{11361}{11463}Practically all of them depend|on the sea for their food,
{11465}{11571}so year-round access to it|is essential for their survival.
{11573}{11639}In the summer, when the sea ice melts,
{11641}{11717}they can reach the islands|that were trapped in the ice
{11719}{11760}and eventually the continent itself.
{11769}{11873}But when the ice re-forms,|they have to retreat north.
{11877}{11931}So now, in winter,
{11933}{12003}with the sea ice at its fullest extent,
{12005}{12094}it's in the sea that we must look for life.
{12467}{12551}The southern ocean is extremely rich in food.
{12553}{12614}Millions of penguins and seals
{12616}{12703}and thousands of whales feed here.
{13063}{13177}The majority of them rely|on just one source of food -
{13179}{13223}krill.
{13391}{13506}Krill are small, shrimp-like creatures|about six centimetres long.
{13509}{13601}In winter, they are dispersed widely,|mostly under the ice,
{13605}{13688}but in summer|they assemble in vast swarms,
{13690}{13769}some of which may contain|a billion individuals.
{13828}{13920}They are the most numerous animals on Earth.
{13922}{14055}Their total weight far exceeds|that of the total human population.
{14288}{14338}Humpback whales.
{14340}{14447}During the brief summer,|they gorge themselves on krill.
{14743}{14813}When the krill swarms are near the surface,
{14815}{14896}the humpbacks collect them by lunging.
{15098}{15173}They simply open their cavernous mouths
{15177}{15225}and scoop it up.
{15350}{15405}0ften the whales co-operate,
{15407}{15482}working together as fishing boats do.
{15991}{16054}When the krill is more dispersed,
{16056}{16110}the whales have to dive deeper.
{16180}{16297}After a while,|lines of bubbles appear on the surface.
{16373}{16470}The bubbles gradually|form a pattern that spirals inwards.
{16611}{16671}Then suddenly, in its centre,
{16673}{16721}the whales appear.
{16970}{17027}Time and again, the pair dive.
{17041}{17098}When they reach the bottom of the dive,
{17102}{17136}they start releasing bubbles
{17138}{17197}and continue to do so as they swim upwards,
{17199}{17254}spiralling around one another.
{17282}{17423}These curtains of bubbles rise through the water,|creating a ring on the surface.
{17546}{17652}Underwater, the curtains drive|the krill into the centre of the spiral
{17654}{17725}and the humpbacks|then surge up through the middle,
{17729}{17774}jaws agape.
{18239}{18301}The humpbacks that visit Antarctica
{18303}{18377}only feed during the brief southern summer,
{18379}{18419}building their reserves
{18421}{18508}for a winter that will be spent|in less productive northern waters.
{18510}{18558}And so, for hour after hour
{18560}{18626}throughout the long Antarctic day,
{18628}{18678}these 40-tonne creatures
{18680}{18808}perform a splendidly synchronised|and very productive underwater ballet.
{18987}{19070}0ther creatures benefit|from the whales' industry.
{19074}{19133}Sea birds forage in their wake.
{19318}{19411}As the whales drive the krill|closer to the surface,
{19413}{19521}it comes within reach of birds|that are not particularly skilled in diving.
{19609}{19677}Cape petrels, about the size of pigeons,
{19681}{19751}can only duck-dive a few feet down.
{19818}{19884}But that's enough to give them a share.
{20485}{20630}360 million sea birds constantly scour|the southern ocean for food.
{20637}{20698}They only go to land to breed.
{20700}{20766}Most of their lives are spent on the wing,
{20768}{20815}far out to sea.
{20942}{20996}This ocean is rich in nutrients
{20998}{21041}and very rough.
{21043}{21111}Howling gales whip it into huge waves.
{21113}{21208}These, with so few islands|to interrupt and break them,
{21210}{21317}grow and grow into some|of the most mountainous seas
{21319}{21383}to be found in any ocean.
{21781}{21854}Birds, dispersed over its vast surface,
{21858}{21920}face a huge problem in finding food,
{21922}{22022}for it is by no means|uniformly spread throughout the ocean.
{22024}{22071}The nutrients occur in patches,
{22073}{22153}and so the krill, which is|sustained by those nutrients,
{22155}{22200}is patchy too.
{22229}{22342}But once the birds find a swarm,|there is a frenzy of feeding.
{22556}{22653}Krill typically spends the day in deep water,
{22655}{22714}rising nearer to the surface at night.
{22716}{22789}But sometimes a swarm rises during the day
{22793}{22855}and then the birds get their chance.
{22900}{22946}But getting to the krill
{22948}{23030}is still a major problem|to all birds except penguins.
{23035}{23148}Albatrosses such as the black-browed,|whose diet is about 40% krill,
{23150}{23239}can only dive down|a couple of metres at the most.
{23663}{23748}Fur seals also feed out in the open ocean,
{23750}{23847}but they are able to dive|to 100 metres or more.
{24997}{25040}The patchiness of the krill
{25042}{25142}requires those that live on it|to spend a great deal of time searching,
{25144}{25245}and an albatross will fly hundreds,|sometimes thousands of miles,
{25247}{25300}on a single foraging trip.
{25332}{25401}0ut here, birds can't afford to be fussy,
{25403}{25472}and must take whatever food they can find.
{25474}{25559}Almost all of them scavenge to some extent.
{25598}{25688}These birds have found|the remains of a small whale.
{25757}{25866}They are the crumbs left behind|after a catch by killer whales.
{26376}{26462}Giant petrels -|the vultures of the Antarctic -
{26464}{26514}soon dominate the feast.
{26635}{26695}(SCREECHING)
{26950}{27007}The biggest of all these scavengers
{27009}{27066}is the wandering albatross.
{27068}{27121}With a wing-span of over three metres,
{27123}{27214}this bird can range over greater|distances than any other.
{27252}{27359}It needs the updraught|created by waves in order to fly,
{27361}{27478}and only these stormy southern waters|provide that in such abundance.
{27548}{27655}Throughout the winter, the wandering|albatross remain in the south,
{27657}{27723}for although the continent is trapped in ice,
{27725}{27834}there are a few outer islands|that always remain beyond its grasp,
{27836}{27932}and these provide the albatross|with their nesting sites.
{28066}{28171}3,000 pairs of wandering albatross|nest on one of them,
{28173}{28225}here in South Georgia.
{28642}{28726}An adult wanderer may travel 5,000 miles -
{28728}{28782}sometimes to Brazil and back -
{28784}{28851}in order to collect squid for its young.
{29844}{29952}This enormous chick weighs ten kilos,
{29954}{30018}as much as a full-grown swan.
{30020}{30105}It's the biggest of any sea bird chick.
{30107}{30221}Although it's a couple of months|before it has to face its first flight,
{30223}{30278}it's now at its maximum weight.
{30280}{30341}In fact, it's heavier even...
{30343}{30381}(HE LAUGHS)
{30415}{30471}...heavier than the adult.
{30473}{30555}The spring snows are now beginning to melt,
{30557}{30649}but the chick has already faced|the worst of the winter weather.
{30653}{30699}Hatched last March,
{30701}{30760}it has sat here on its nest mound
{30762}{30840}unprotected and unshielded for eight months
{30844}{30926}while the temperatures may have|fallen to minus 10 degrees
{30928}{30992}and terrible storms raged.
{30996}{31120}It's so big that it can't possibly|grow to this very huge size
{31122}{31175}in the short summer season.
{31177}{31263}So the parents have to come to feed it
{31265}{31353}every three or four days for 10 months.
{31355}{31472}In order to do that,|they have to be able to reach the open sea.
{32166}{32276}0nly one other animal breeds|throughout the year on the outer islands -
{32278}{32318}King penguins.
{32320}{32396}They also need continuous access to the ocean
{32398}{32450}to collect food for their chicks.
{33613}{33657}Throughout the winter,
{33659}{33743}adults come and go from their|traditional breeding colonies.
{33747}{33823}(DIN 0F SQUAWKING)
{33842}{33946}Antarctica is home to two million Kings.
{33948}{34060}In this one colony alone,|there are 600,000 of them.
{34135}{34230}These engaging chicks are so inquisitive
{34232}{34319}that you only have|to sit down to their own level
{34321}{34372}for them all to gather round you
{34374}{34453}and try and discover|what sort of creature you are.
{34455}{34510}They were hatched last summer
{34514}{34566}and, like the albatross chicks,
{34568}{34659}they're coming to the end|of their first winter.
{34663}{34766}During that period, their parents|were out to sea catching food for them,
{34768}{34868}but each chick was only fed|about once every three weeks.
{34873}{34955}Left to themselves for so long,
{34957}{35064}they've all gathered together|to form immense crèches.
{35066}{35155}This one contains about 50,000 chicks.
{35157}{35293}You might think that this huge congregation|would make it almost impossible
{35295}{35392}for a parent returning with food|to find its own chick.
{35394}{35559}Not so - the fact is that parent and chick|can recognise one another's voice.
{35599}{35699}(DIN 0F CALLS AND WHISTLES)
{35726}{35868}A returning adult may spend hours|looking for its chick among such a crowd,
{35870}{35929}for the young are inclined to wander.
{36007}{36091}The chick will respond to its parent's call
{36095}{36161}and the parent to the chick's whistle.
{36246}{36320}Eventually they meet...
{36322}{36411}(CHICK WHISTLES VERY L0UDLY)
{36415}{36482}...but instead of feeding|the chick straight away,
{36484}{36545}the adult leads it through the rookery,
{36547}{36617}as if to test the bond between them.
{36676}{36773}At last, in response|to its chick's plaintive entreaties,
{36777}{36862}the parent regurgitates a meal of squid.
{37229}{37332}A King penguin chick|takes more than 12 months to rear,
{37334}{37411}so the adults can't breed annually.
{37414}{37495}At best, they raise two chicks|every three years.
{37499}{37579}Because of this,|the breeding cycle of any one pair
{37581}{37665}slides out of phase with the seasons.
{37669}{37716}So now, late in winter,
{37718}{37769}there are chicks both young and old
{37771}{37849}and adults at different stages in their cycle.
{37853}{37951}Some of the adults are going|through their pre-breeding moult
{37953}{38044}before going to sea|to fatten up for courtship.
{38048}{38119}0thers are already courting,
{38123}{38222}parading back and forth|with a special ritualised walk.
{38832}{38898}The male usually leads.
{38968}{39044}If the female is sufficiently impressed,
{39046}{39140}the pair seal their relationship|with a vocal duet.
{39142}{39259}(MALE AND FEMALE|TAKE IT IN TURNS T0 CALL)
{39579}{39683}King penguin rookeries are very busy places.
{39685}{39736}Every morning at about six o'clock,
{39740}{39792}the adults leave their chicks,
{39794}{39846}cross the glacier stream
{39850}{39902}and march down to the sea.
{40046}{40121}They like to take an early morning bath,
{40123}{40233}getting rid of the smelly mud|and grime of the crowded colony.
{41047}{41104}For an hour or so,
{41106}{41157}they wash in the surf.
{41635}{41730}These penguins seem to have|a fairly easy time of it,
{41732}{41795}surrounded by an ocean laden with food
{41797}{41872}and with year-round access|to their breeding beaches.
{41874}{41949}But they are one of the few|of Antarctica's inhabitants
{41951}{42045}to achieve independence from the factor|that governs almost everything else -
{42049}{42131}the advance and retreat of the sea ice.
{42160}{42282}King penguin and albatross live only|on the frontier of the Antarctic.
{42284}{42384}They never go closer to the pole|than the edge of the sea ice.
{42386}{42439}Next week, we will.
{42441}{42491}As spring really takes hold,
{42493}{42577}we will follow the retreating sea ice|to the shores of the continent
{42579}{42677}and go up to the great ice cap,|to the very heart of the Antarctic,
{42679}{42785}where life in the freezer|faces its greatest challenge.