0:00:02 > 0:00:04Midwinter in Antarctica,
0:00:04 > 0:00:07and one of nature's most extraordinary stories
0:00:07 > 0:00:09is about to begin.
0:00:10 > 0:00:15Through two months of biting winds, blizzards and unimaginable cold,
0:00:15 > 0:00:20these male emperor penguins have each nurtured a single precious egg.
0:00:21 > 0:00:25One by one, they welcome their tiny chicks into the world.
0:00:39 > 0:00:44But not all eggs will hatch, and one father is still waiting.
0:00:50 > 0:00:53A neighbour shows off his own new youngster.
0:00:59 > 0:01:03His calls will encourage the chick to emerge.
0:01:12 > 0:01:16Finally, the youngest member of the colony is born.
0:01:18 > 0:01:20But growing up in the world's most extreme nursery
0:01:20 > 0:01:23will be a huge challenge,
0:01:23 > 0:01:27for in just six months he must have learned enough to fend for himself
0:01:27 > 0:01:30in the great Antarctic Ocean.
0:01:30 > 0:01:35This is the dramatised story of one extraordinary little bird.
0:01:44 > 0:01:46Far from their chicks,
0:01:46 > 0:01:47the mothers have spent
0:01:47 > 0:01:48the last two months
0:01:48 > 0:01:50catching fish and fattening up
0:01:50 > 0:01:52while the fathers were left alone
0:01:52 > 0:01:53to hatch their eggs.
0:01:55 > 0:01:58Now the race is on to get back and feed their young.
0:02:01 > 0:02:05Among the excited crowd is Snow Chick's mother.
0:02:12 > 0:02:16She's got a belly full of fish for her newborn,
0:02:16 > 0:02:21but between them is a gruelling 60-mile trek across the frozen sea.
0:02:23 > 0:02:28Waddling at less than 2mph, it will take many days to get home.
0:02:40 > 0:02:43Instinct drives them on -
0:02:43 > 0:02:46their babies' lives depend on them arriving in time.
0:02:50 > 0:02:54Back at the colony, the father is getting to know his chick.
0:02:56 > 0:02:59He gives him some high-calorie baby milk
0:02:59 > 0:03:01produced from a gland in his throat.
0:03:02 > 0:03:06But these supplies will only last a few days.
0:03:09 > 0:03:12It's just as well his mother is on her way.
0:03:19 > 0:03:24Following her maternal instinct, she and all the other females
0:03:24 > 0:03:27are making steady progress on their journey home.
0:03:28 > 0:03:31But in places the ice is wafer-thin.
0:03:35 > 0:03:40Below, a predator tracks their every move.
0:03:43 > 0:03:46A leopard seal, the penguins' greatest enemy.
0:04:00 > 0:04:03The chick's mother senses danger.
0:04:07 > 0:04:09PENGUINS CALL
0:04:21 > 0:04:23She was right to be cautious.
0:04:37 > 0:04:39Broken ice is a deathtrap.
0:04:55 > 0:04:58For the rest, their chick is their only concern.
0:04:59 > 0:05:03But the seal needs just one victim.
0:05:18 > 0:05:20A near miss,
0:05:20 > 0:05:23and she still has 40 treacherous miles ahead of her.
0:05:35 > 0:05:38While the chick waits for her return,
0:05:38 > 0:05:41outside temperatures are at -30.
0:05:42 > 0:05:45But the pouch covers him like a tea cosy
0:05:45 > 0:05:48and keeps him at a comfy +37 degrees.
0:06:00 > 0:06:02For a new father,
0:06:02 > 0:06:06walking with a chick on your feet is a tricky balancing act.
0:06:33 > 0:06:35He'll get the hang of it soon.
0:06:38 > 0:06:41The mothers are also struggling with the icy conditions
0:06:41 > 0:06:44and they are crossing some of the toughest terrain on earth.
0:06:48 > 0:06:51Their sharp claws grip the ice,
0:06:51 > 0:06:53while scales on their feet
0:06:53 > 0:06:54act like treads.
0:06:55 > 0:06:58But where the snow melts and re-thaws,
0:06:58 > 0:07:02it creates slippery conditions that even a penguin finds challenging.
0:07:47 > 0:07:51Back at the colony, it's been a week since the chick was born.
0:07:51 > 0:07:55At these temperatures, survival depends on getting enough to eat.
0:07:59 > 0:08:02His father tries, but there's nothing left to give.
0:08:09 > 0:08:11The mothers battle on.
0:08:13 > 0:08:17Sadly, some years they simply don't make it in time.
0:08:21 > 0:08:24The chick is getting weaker by the hour.
0:08:45 > 0:08:48Then, at last, some weary figures appear.
0:09:07 > 0:09:09Utterly exhausted by the walk,
0:09:09 > 0:09:11the mother still has one final challenge
0:09:11 > 0:09:14before she can meet her chick.
0:09:17 > 0:09:19Finding him.
0:09:20 > 0:09:24There are over 3,000 fathers with chicks here
0:09:24 > 0:09:27and, even to penguins, they all look the same.
0:09:32 > 0:09:35For the chick, time is running out.
0:09:37 > 0:09:39But the penguins have a solution.
0:09:39 > 0:09:44The fathers get in line and dad and his chick join them.
0:09:49 > 0:09:52They form an identity parade.
0:09:55 > 0:10:00All she has to do is simply work her way along the line.
0:10:04 > 0:10:06Sounds simple enough,
0:10:06 > 0:10:09but among all the penguin lookalikes,
0:10:09 > 0:10:12her partner is still tricky to recognise.
0:10:14 > 0:10:17So, every so often, she stops and calls.
0:10:17 > 0:10:19PENGUIN CALLS
0:10:23 > 0:10:28Her cry is unique and the father responds with a call of his own.
0:10:28 > 0:10:31PENGUIN CALLS
0:10:31 > 0:10:34PENGUIN CHICK CHEEPS
0:10:34 > 0:10:37It's what she was hoping to hear.
0:10:40 > 0:10:46After two months at sea and a 60-mile trek across the ice,
0:10:46 > 0:10:48she's made it back in the nick of time.
0:11:02 > 0:11:05In a miracle of natural timing,
0:11:05 > 0:11:09he gets a morsel that will save his life.
0:11:20 > 0:11:23It's now his mother's turn to take over the childcare...
0:11:25 > 0:11:26..but they must be careful -
0:11:26 > 0:11:30a few seconds too long on the ice and their chick will die.
0:11:51 > 0:11:55Finally, they unite as a family.
0:11:56 > 0:12:01The bond they share is one of the most remarkable in nature.
0:12:10 > 0:12:13For over the next five months,
0:12:13 > 0:12:16they'll take it in turns to trek to the sea to bring back food
0:12:16 > 0:12:19for their ever-growing baby.
0:12:30 > 0:12:33PENGUIN CHICK CHEEPS
0:12:35 > 0:12:39His father endured so much to get the tiny chick this far.
0:12:40 > 0:12:42Saying goodbye is hard.
0:12:47 > 0:12:49This time, there's no looking back.
0:12:51 > 0:12:55In four weeks, he will return with fresh supplies.
0:12:58 > 0:13:04But first, there's the little matter of a 120-mile round-trip to the sea.
0:13:09 > 0:13:10Now it's Mum's turn to feed him.
0:13:11 > 0:13:13A natural preservative
0:13:13 > 0:13:16has kept the fish as fresh as the day it was caught.
0:13:21 > 0:13:26The chick may be satisfied, but his father hasn't eaten for four months.
0:13:26 > 0:13:29He and the rest of the hungry fathers
0:13:29 > 0:13:32are now two days into their long walk to the sea.
0:13:36 > 0:13:39But sometimes the ice offers a short-cut.
0:13:41 > 0:13:42An ice hole,
0:13:42 > 0:13:46a portal to the sea which could cut their journey by days.
0:13:48 > 0:13:52And when you're famished, it's got to be worth investigating.
0:13:58 > 0:14:01But such holes don't appear by themselves.
0:14:06 > 0:14:08There had to be a catch.
0:14:11 > 0:14:15They can either stay and hope the leopard seal goes away
0:14:15 > 0:14:18or continue their long, risky trek to the sea.
0:14:19 > 0:14:23Time to regroup, this must be a joint decision.
0:14:26 > 0:14:29Emperors rely on each other for their very survival,
0:14:29 > 0:14:32so learning social skills starts early.
0:14:37 > 0:14:40Penguins are naturally argumentative,
0:14:40 > 0:14:43so his first lesson is sticking up for himself.
0:15:00 > 0:15:05His mother only intervenes when things go too far.
0:15:07 > 0:15:10But no kid likes being told off.
0:15:17 > 0:15:20At the ice hole, the standoff continues.
0:15:29 > 0:15:31No-one is keen to be first.
0:15:34 > 0:15:37But they egg each other on, as penguins like to do.
0:15:51 > 0:15:52The coast is clear.
0:15:52 > 0:15:54Their gamble paid off.
0:16:07 > 0:16:10At the colony, two weeks have passed.
0:16:10 > 0:16:13The chicks are testing their independence
0:16:13 > 0:16:15and spending time away from their mothers.
0:16:17 > 0:16:21All, that is, except one.
0:16:26 > 0:16:30As the last to hatch, he's way behind in development.
0:16:32 > 0:16:35While the older chicks are boisterous and confident,
0:16:35 > 0:16:39he still feels most comfortable in his mother's pouch.
0:16:42 > 0:16:44But penguins are sociable birds,
0:16:44 > 0:16:49and to survive, he must learn to play his part in the colony.
0:16:52 > 0:16:54It's a daunting prospect...
0:16:56 > 0:16:59..but the little chick finds some courage.
0:17:26 > 0:17:31SNOW CHICK CHEEPS
0:17:31 > 0:17:33It's a shaky start,
0:17:33 > 0:17:36but he mustn't lose his nerve.
0:17:36 > 0:17:38Time for a bit of tough love.
0:17:45 > 0:17:48With every step, he gains more confidence.
0:17:54 > 0:17:58It's just as well - he has so many friends to make.
0:18:08 > 0:18:10But when you're the smallest,
0:18:10 > 0:18:12it's tough to join the gang.
0:18:29 > 0:18:32PENGUIN CALLS
0:18:32 > 0:18:35For now, there's always Mum.
0:18:40 > 0:18:42Out in the open ocean,
0:18:42 > 0:18:46the fathers are revelling in being back in the water.
0:18:50 > 0:18:53They haven't eaten for four whole months
0:18:53 > 0:18:55and have lost half their body weight.
0:19:01 > 0:19:03To stock up on fish and squid,
0:19:03 > 0:19:06they hold their breath for up to 20 minutes
0:19:06 > 0:19:09and dive to nearly 2,000 feet,
0:19:09 > 0:19:11deeper than any other bird.
0:19:22 > 0:19:25At the colony, three weeks have passed
0:19:25 > 0:19:29and the chick is confidently following his mother
0:19:29 > 0:19:30wherever she goes.
0:19:31 > 0:19:34He's still learning how things should be done...
0:19:35 > 0:19:37..and how they shouldn't.
0:19:45 > 0:19:47He soon thinks there's nothing left to learn...
0:19:52 > 0:19:57..so nervous toddler turns cocky explorer.
0:19:57 > 0:20:00But at this age, she mustn't let him out of her sight.
0:20:17 > 0:20:19PENGUIN CALLS
0:20:32 > 0:20:34She's lost him
0:20:34 > 0:20:36and heads off in the wrong direction.
0:21:03 > 0:21:07Confused, he does the only sensible thing
0:21:07 > 0:21:09and heads towards the colony.
0:21:32 > 0:21:34He feels safer now.
0:21:34 > 0:21:36His mother must be here somewhere.
0:21:44 > 0:21:47And then, security at last.
0:21:48 > 0:21:50But he's got it wrong,
0:21:50 > 0:21:53it's not his mother.
0:22:00 > 0:22:03This must be her, surely?
0:22:06 > 0:22:07Wrong again.
0:22:20 > 0:22:25He tests each penguin in turn, but nobody wants him.
0:22:28 > 0:22:33In a colony this size, he may never find his mother again.
0:22:39 > 0:22:41These are desperate times.
0:22:41 > 0:22:45In this frozen world, lost chicks don't survive for long.
0:22:47 > 0:22:51His father is among the many rushing back with fresh supplies,
0:22:51 > 0:22:53but he must be careful.
0:22:58 > 0:23:01A pod of killer whales are on their tail.
0:23:21 > 0:23:24They look for any penguin that makes a mistake.
0:23:35 > 0:23:38Just a tiny error, but now he's in deep trouble.
0:23:50 > 0:23:52He torpedoes to safety...
0:23:59 > 0:24:03..but killer whales are intelligent and persistent predators
0:24:03 > 0:24:07and the spring melt has turned the ice edge
0:24:07 > 0:24:10into a maze of gullies and openings,
0:24:10 > 0:24:13perfect for a surprise attack.
0:24:35 > 0:24:38To keep him in their sights, they spy-hop.
0:24:41 > 0:24:45He must find a safe passage out by staying on solid ice.
0:24:48 > 0:24:51He sees a route and heads for safety.
0:25:01 > 0:25:04A reprieve of sorts,
0:25:04 > 0:25:07but the other fathers left without him.
0:25:13 > 0:25:15And with a storm brewing, he's totally exposed.
0:25:31 > 0:25:33Already, the blizzard has reached the colony.
0:25:36 > 0:25:39The chick's only protection is his overcoat of down
0:25:39 > 0:25:44and at -40, it's simply not enough.
0:25:54 > 0:25:59And unfortunately, the other mothers care only for their own.
0:26:00 > 0:26:03SNOW CHICK CHEEPS
0:26:06 > 0:26:09The chick's mother calls one last time...
0:26:11 > 0:26:13..but her cries are lost on the wind.
0:26:13 > 0:26:17PENGUIN CALLS, WIND HOWLS
0:26:38 > 0:26:39At last, he's found...
0:26:42 > 0:26:44..and not a moment too soon.
0:26:58 > 0:27:00But out on the ice,
0:27:00 > 0:27:04the lone father is still paying the price for his mistake.
0:27:27 > 0:27:32Within a few hours, the full force of the storm engulfs the colony.
0:27:35 > 0:27:36The chick may be safe,
0:27:36 > 0:27:39but as temperatures drop to -60,
0:27:39 > 0:27:41his mother's warmth is not enough.
0:27:42 > 0:27:45To protect him, she needs to find refuge
0:27:45 > 0:27:48in the shared warmth of the other penguins.
0:27:57 > 0:28:02As 70mph winds lash the colony, the penguins huddle together.
0:28:14 > 0:28:17Sheltered from the storm, they're snug at last.
0:28:24 > 0:28:28Out in the open, the father's chances are slim.
0:28:28 > 0:28:32His only hope is to reach the safety of the colony in time.
0:28:39 > 0:28:41In the comfort of the huddle,
0:28:41 > 0:28:45the penguins have all the shelter they need.
0:28:45 > 0:28:50In the centre, temperatures can even reach a toasty 37 degrees.
0:28:50 > 0:28:53To cool down, they shuffle to the outside,
0:28:53 > 0:28:55letting others take their place.
0:28:57 > 0:29:01By sharing body heat, they weather any storm.
0:29:03 > 0:29:06Desperate for the warmth of the family,
0:29:06 > 0:29:08the lone father struggles on.
0:29:08 > 0:29:12For the sake of his chick, he simply has to make it back.
0:29:19 > 0:29:21PENGUIN CALLS
0:29:24 > 0:29:27Then, through the blizzard, salvation.
0:29:39 > 0:29:42Against the odds, he's made it home.
0:30:19 > 0:30:21A few weeks pass
0:30:21 > 0:30:23and the days are lengthening.
0:30:24 > 0:30:25Dad is on parenting duties
0:30:25 > 0:30:28while Mum takes the fishing shift.
0:30:29 > 0:30:31But even in the safety of the colony,
0:30:31 > 0:30:33there are unexpected dangers.
0:30:35 > 0:30:37Penguins who have failed to breed
0:30:37 > 0:30:40practise child-rearing skills on chunks of ice.
0:30:43 > 0:30:46But their mothering instinct is so overwhelming,
0:30:46 > 0:30:49what they really want is a baby of their own.
0:30:53 > 0:30:57And who better than the smallest, most adorable chick in the colony?
0:31:05 > 0:31:08Dad has his work cut out keeping these kid-snatchers at bay.
0:31:11 > 0:31:13And they aren't the only broody penguins...
0:31:18 > 0:31:20Soon, there are so many baby-snatchers,
0:31:20 > 0:31:23they block the father's path at every turn.
0:31:23 > 0:31:25PENGUINS CALL
0:31:27 > 0:31:30As his chick gets smothered by admirers,
0:31:30 > 0:31:32there's nothing he can do.
0:31:38 > 0:31:40For these lone females,
0:31:40 > 0:31:44the urge to nurture a chick of their own is overwhelming.
0:31:44 > 0:31:48In the frenzy, they are in danger of loving him to death.
0:32:02 > 0:32:04CHICK CHEEPS
0:32:10 > 0:32:15When Dad can finally reach him, his little chick is in real peril.
0:32:16 > 0:32:18Then a lucky break -
0:32:18 > 0:32:20he gets his battered baby back.
0:32:27 > 0:32:31Nothing is more important than the safety of your young.
0:32:36 > 0:32:38As the weeks go by, spring turns to summer.
0:32:38 > 0:32:43The sea ice melts and the ocean gets closer.
0:32:51 > 0:32:56It means feeding the chicks is easy, so they are growing up fast.
0:33:04 > 0:33:08They hang out together in small, comforting huddles.
0:33:15 > 0:33:17But Snow Chick isn't ready to cut the ties,
0:33:17 > 0:33:21despite being too big for his father's pouch.
0:33:33 > 0:33:36It's starting to get embarrassing...
0:33:43 > 0:33:45It's long overdue,
0:33:45 > 0:33:49but his father finally persuades him to find his place in the gang.
0:33:59 > 0:34:01But there's an art to joining a huddle
0:34:01 > 0:34:03and he hasn't mastered it.
0:34:05 > 0:34:07But practice makes perfect,
0:34:07 > 0:34:10and the first thing to work out is which way to face.
0:34:18 > 0:34:23You know you've got it right when someone snuggles in behind you.
0:34:23 > 0:34:25Accepted at last.
0:34:26 > 0:34:29This is a huge milestone in his development -
0:34:29 > 0:34:33it means that, for the first time, both parents can go fishing.
0:34:36 > 0:34:39The chick is not so sure he's ready to be left on his own.
0:34:55 > 0:34:58But the colony has invisible walls
0:34:58 > 0:35:00and he instinctively knows
0:35:00 > 0:35:02they mustn't be crossed.
0:35:13 > 0:35:14The adults left behind
0:35:14 > 0:35:17don't have the caring ways of his parents.
0:35:23 > 0:35:28Until they return, he must find one of the colony's childminders.
0:35:28 > 0:35:33A penguin who hasn't bred takes on the role as practice for the future.
0:35:41 > 0:35:42She'll take him under her wing,
0:35:42 > 0:35:45but only if he does as he's told.
0:35:48 > 0:35:50She's a firm believer in discipline.
0:36:01 > 0:36:03With so many chicks in her care,
0:36:03 > 0:36:06stragglers won't be tolerated.
0:36:06 > 0:36:09He will just have to toughen up.
0:36:16 > 0:36:18But there's a reason for the new, strict regime.
0:36:21 > 0:36:22With the warmer days,
0:36:22 > 0:36:24the open sea is closer now
0:36:24 > 0:36:30and new and unwelcome visitors can reach the colony easily.
0:36:38 > 0:36:40CHEEPING
0:36:42 > 0:36:43A giant petrel.
0:36:50 > 0:36:52They always pick on the smallest.
0:36:56 > 0:36:57He's caught!
0:36:58 > 0:37:00But just by his baby fluff.
0:37:07 > 0:37:09The childminder is welcome now.
0:37:21 > 0:37:24It's now a deadly game of hide-and-seek.
0:37:41 > 0:37:44Luckily, the petrel spots an easier meal of scraps...
0:37:51 > 0:37:54..and the chick has learned a valuable lesson.
0:38:02 > 0:38:03As spring continues,
0:38:03 > 0:38:06the melting ice brings another new arrival.
0:38:06 > 0:38:08PENGUIN SQUAWKS
0:38:13 > 0:38:14The Adelie penguin.
0:38:19 > 0:38:23A cocky character, very different to the laid-back emperor.
0:38:31 > 0:38:33Adelies breed in the Antarctic summer.
0:38:33 > 0:38:35He's the first to arrive
0:38:35 > 0:38:38and he's heading straight for his breeding grounds...
0:38:40 > 0:38:44..exactly where the emperors are living.
0:38:46 > 0:38:50These days, the smallest chick is one of the gang
0:38:50 > 0:38:52and the youngsters do everything together.
0:38:52 > 0:38:56But this new-found harmony is about to be rudely interrupted.
0:39:01 > 0:39:04When the Adelie reaches the colony, he's on a mission.
0:39:07 > 0:39:09He's setting up home for the summer
0:39:09 > 0:39:12and he expects to have the place to himself.
0:39:16 > 0:39:19Adelies are only half a metre tall,
0:39:19 > 0:39:22but they're the most pugnacious of all penguins -
0:39:22 > 0:39:26he thinks nothing of taking on the whole colony.
0:39:31 > 0:39:34Chicks that don't give way soon get the message.
0:39:36 > 0:39:40He'll be a thorn in their side until he's seen the back of them.
0:39:53 > 0:39:56In the meantime, he makes himself at home.
0:40:04 > 0:40:07As the melt brings the sea ever closer,
0:40:07 > 0:40:09the parents visit their chicks more frequently.
0:40:17 > 0:40:20The littlest still has some catching up to do,
0:40:20 > 0:40:23but with this continuous relay of food,
0:40:23 > 0:40:26everyone is piling on the pounds.
0:40:26 > 0:40:28When the chick isn't eating,
0:40:28 > 0:40:31he spends his time hungrily waiting for his next meal.
0:40:38 > 0:40:40When his mother does arrive,
0:40:40 > 0:40:45she's plagued by greedy chicks, all trying to blag a free lunch.
0:40:50 > 0:40:52But if she feeds any of these impostors,
0:40:52 > 0:40:54her chick will go hungry.
0:40:58 > 0:41:01He's hidden somewhere in the huddle.
0:41:01 > 0:41:06To find him, she must use her unique and comforting call.
0:41:07 > 0:41:10MOTHER CALLS
0:41:19 > 0:41:22The chicks are so tightly packed,
0:41:22 > 0:41:24he can only reach her by crowd-surfing.
0:41:39 > 0:41:41Even now, he must undergo an identity check
0:41:41 > 0:41:43before he gets a meal.
0:41:56 > 0:42:00Fortunately, he passes the test.
0:42:08 > 0:42:09With the warming weather,
0:42:09 > 0:42:12the snow melts in the day but refreezes at night,
0:42:12 > 0:42:16creating the perfect conditions for sheet ice.
0:42:17 > 0:42:19The adults test out the new ice rink.
0:42:30 > 0:42:35But in a land of ice and snow, it's a skill all must learn.
0:42:40 > 0:42:43For the smallest chick, it's yet another challenge...
0:42:48 > 0:42:52..and his feet don't make the greatest ice skates.
0:42:56 > 0:42:59But we all learn from our mistakes.
0:43:18 > 0:43:20Not everyone is struggling with the conditions.
0:43:23 > 0:43:28Nimbler and faster, the Adelie has a skating style all of his own.
0:43:52 > 0:43:56He's still a lone warrior, but he won't be for long.
0:43:56 > 0:43:59Reinforcements are on their way.
0:44:01 > 0:44:02More Adelies...
0:44:08 > 0:44:09Hundreds of them!
0:44:34 > 0:44:38They're ready to breed and nothing will stand in their way.
0:44:43 > 0:44:46They time-share these breeding grounds with the emperors
0:44:46 > 0:44:49and the summer season is their turn.
0:45:08 > 0:45:11If you're small, it's best to keep a low profile
0:45:11 > 0:45:14and hope they'll pick on someone their own size.
0:45:17 > 0:45:20While the bigger chicks are squaring up,
0:45:20 > 0:45:22he makes his exit.
0:45:22 > 0:45:24SQUAWKING
0:45:45 > 0:45:49When the new neighbours aren't picking fights with the chicks,
0:45:49 > 0:45:52they argue amongst themselves.
0:45:52 > 0:45:54LOUD SQUAWKING
0:45:59 > 0:46:01The Adelie invasion
0:46:01 > 0:46:04is also a sign of a bigger and more profound change.
0:46:06 > 0:46:08After five months of nurturing,
0:46:08 > 0:46:13the adults are preparing to leave their chicks for good.
0:46:13 > 0:46:17A conveyer belt of food is now arriving around the clock,
0:46:17 > 0:46:20building them up until they can fend for themselves.
0:46:22 > 0:46:27From the smallest to the largest, the chicks are getting huge meals -
0:46:27 > 0:46:32up to five kilos of fish in a single session.
0:46:43 > 0:46:45But when you're always hungry,
0:46:45 > 0:46:47everyone else seems to be getting more!
0:46:52 > 0:46:55Many adults are leaving the colony for the last time...
0:46:58 > 0:47:03..and the smallest chick here still has some feeding up to do
0:47:03 > 0:47:05and his parents are nowhere to be seen.
0:47:16 > 0:47:18Then, two familiar figures.
0:47:34 > 0:47:36It's double helpings this time.
0:47:46 > 0:47:49He'll need the extra nourishment -
0:47:49 > 0:47:50he doesn't know it yet,
0:47:50 > 0:47:54but this is the last meal he'll ever get from them.
0:48:07 > 0:48:10Without so much as a backward glance,
0:48:10 > 0:48:13Mum and Dad head back to sea.
0:48:13 > 0:48:15Their work is done.
0:48:15 > 0:48:17The chick they spent five months rearing
0:48:17 > 0:48:21must now stand on his own two feet.
0:48:29 > 0:48:31All the chicks have been abandoned,
0:48:31 > 0:48:34just a few baby-sitters remain.
0:48:35 > 0:48:37They exercise their flippers
0:48:37 > 0:48:40as they prepare for the next phase in their lives -
0:48:40 > 0:48:44four years at sea in the Antarctic Ocean.
0:48:45 > 0:48:47It's something even the smallest must do.
0:48:50 > 0:48:53He'll soon be using these flippers in earnest,
0:48:53 > 0:48:57but right now, no-one seems ready to make the long trek to the sea.
0:49:06 > 0:49:10A week goes by and the weather deteriorates.
0:49:15 > 0:49:18All that time, the chicks have been waiting,
0:49:18 > 0:49:22but their parents never returned.
0:49:27 > 0:49:30Even the Adelie seems confused.
0:49:34 > 0:49:37Eventually, driven by hunger and instinct,
0:49:37 > 0:49:41their only choice is to cross the colony's invisible boundary
0:49:41 > 0:49:45and begin the most important journey of their lives.
0:49:48 > 0:49:51The Adelie couldn't be happier to see them go.
0:49:51 > 0:49:54He escorts them off the premises.
0:50:01 > 0:50:04As winds reach 80mph,
0:50:04 > 0:50:06the smallest struggles to keep up.
0:50:10 > 0:50:13But he'll only survive if he stays with the group,
0:50:13 > 0:50:15and it's so easy to lose them in a blizzard.
0:50:34 > 0:50:38In temperatures of -20, they battle on,
0:50:38 > 0:50:41driven by a need to reach the sea.
0:50:46 > 0:50:47After several hours,
0:50:47 > 0:50:50the struggling chick is losing energy.
0:50:53 > 0:50:56CHICK CALLS
0:51:16 > 0:51:20Then, even the other chicks can travel no more.
0:51:22 > 0:51:28Completely exhausted, the chick must make one final effort.
0:51:41 > 0:51:47Together, the plucky little gang wait for the storm to pass.
0:51:57 > 0:52:00A few days later, the weather has changed...
0:52:01 > 0:52:03..and so have the chicks.
0:52:05 > 0:52:07As they prepare for a life in the ocean,
0:52:07 > 0:52:09they preen away their baby fluff
0:52:09 > 0:52:12to reveal their adult plumage underneath.
0:52:14 > 0:52:19As ever, one chick has some catching up to do.
0:52:26 > 0:52:29The Adelie wants them on their way
0:52:29 > 0:52:32and encourages them with a little preening of his own.
0:52:40 > 0:52:42SQUAWKING
0:52:59 > 0:53:01Urged on by their escort,
0:53:01 > 0:53:04the ragtag army reach their destination.
0:53:13 > 0:53:17This is their first sight of the sea -
0:53:17 > 0:53:21the great Antarctic Ocean.
0:53:30 > 0:53:34They're facing the greatest challenge of their young lives
0:53:34 > 0:53:38and they'll only go when all are ready.
0:53:41 > 0:53:44But their ice world is disappearing fast.
0:53:58 > 0:54:01He hesitates. Something's wrong.
0:54:03 > 0:54:05The ice gives way,
0:54:05 > 0:54:06he's tossed into the sea.
0:54:14 > 0:54:19He can't go it alone, he must rejoin the others.
0:54:21 > 0:54:23CHICK CALLS
0:54:25 > 0:54:27Then he starts to settle.
0:54:33 > 0:54:36It feels...strangely natural.
0:54:41 > 0:54:44But as the rest show no sign of joining him,
0:54:44 > 0:54:46his only choice is to clamber back out.
0:54:48 > 0:54:51It's far more difficult than getting in
0:54:51 > 0:54:55and it seems he's not alone in the water.
0:55:28 > 0:55:30The chicks head for a safer spot.
0:55:34 > 0:55:37But despite the danger, the ocean is beckoning
0:55:37 > 0:55:40and the excitement is contagious.
0:55:45 > 0:55:48An old foe is here to see them off.
0:55:53 > 0:55:58The chick may still be the smallest but he seems more confident now.
0:56:00 > 0:56:02He may be facing the great unknown,
0:56:02 > 0:56:05but he's already had a taste of the sea.
0:56:06 > 0:56:08He pushes his way to the front.
0:56:08 > 0:56:14After all he has learned, this is his moment.
0:56:14 > 0:56:16He takes a leap of faith...
0:56:21 > 0:56:24..and this time, there is no turning back.
0:56:30 > 0:56:33The rest follow his cue.
0:56:49 > 0:56:50He might have been the smallest,
0:56:50 > 0:56:54but he was strong enough to survive against the odds...
0:57:00 > 0:57:05..and now he leads the penguin gang into the vast Antarctic Ocean.
0:57:08 > 0:57:11This will be their home for the next four years.
0:57:11 > 0:57:14Then, driven by the same feelings that drove his parents,
0:57:14 > 0:57:19Snow Chick will return here to find a partner of his own...
0:57:20 > 0:57:26..and the whole incredible story will begin all over again.