0:00:10 > 0:00:14Looking down from two miles above the surface of the Earth
0:00:14 > 0:00:17it's impossible not to be impressed
0:00:17 > 0:00:20by the sheer grandeur and splendour
0:00:20 > 0:00:23and power of the natural world.
0:00:26 > 0:00:30Ten years ago, in a television series called Planet Earth,
0:00:30 > 0:00:35we revealed many of those wonders, but today, much has changed.
0:00:37 > 0:00:41We can now show life on our planet in entirely new ways.
0:00:44 > 0:00:47Bring you closer to animals than ever before.
0:00:50 > 0:00:55And reveal new wildlife dramas for the very first time.
0:00:59 > 0:01:00But that's not all.
0:01:01 > 0:01:04Our planet has changed too.
0:01:04 > 0:01:08Never have those wildernesses been as fragile and as precious
0:01:08 > 0:01:10as they are today.
0:01:13 > 0:01:16At this crucial time for the natural world,
0:01:16 > 0:01:19we will journey to every corner of the globe...
0:01:21 > 0:01:24..to explore the greatest treasures of our living planet...
0:01:31 > 0:01:35..and reveal the extreme lengths animals go to
0:01:35 > 0:01:36to survive.
0:01:51 > 0:01:55Finally, we will explore our cities
0:01:55 > 0:01:57to see how life is adapting
0:01:57 > 0:02:00to the newest habitat on Earth.
0:02:02 > 0:02:05This is Planet Earth II.
0:02:45 > 0:02:49There are hundreds of thousands of islands,
0:02:49 > 0:02:53each one a world in miniature,
0:02:53 > 0:02:56a microcosm of our living planet.
0:02:57 > 0:03:01The struggles to survive on these remote lands
0:03:01 > 0:03:05reflect the challenges faced by all life on Earth.
0:03:15 > 0:03:20The tiny island of Escudo off the coast of Panama.
0:03:22 > 0:03:26Home to the pygmy three-toed sloth.
0:03:29 > 0:03:32This is a male and life here suits him well.
0:03:36 > 0:03:39Mangroves provide all the leaves he can eat
0:03:39 > 0:03:43and there are no predators to worry him.
0:03:45 > 0:03:50Island life may seem idyllic but it comes at a price.
0:03:51 > 0:03:55There are only a few hundred pygmy sloths in existence.
0:03:56 > 0:03:59And he needs a mate.
0:04:00 > 0:04:03SCREECHING
0:04:03 > 0:04:05That's an enticing call...
0:04:07 > 0:04:08..from a female.
0:04:11 > 0:04:13Somewhere out there.
0:04:16 > 0:04:21And this, for a sloth, is a quick reaction.
0:04:41 > 0:04:43FEMALE SCREECHES AGAIN
0:04:43 > 0:04:47The problem is, there's deep water between them.
0:04:49 > 0:04:52So what should any red-blooded sloth do?
0:04:57 > 0:04:59Swim, of course.
0:05:29 > 0:05:31Could this be her?
0:05:38 > 0:05:42He does his best to put on a turn of speed.
0:05:52 > 0:05:54But she's not the one.
0:05:54 > 0:05:59She already has a baby and she won't mate again until it leaves her
0:05:59 > 0:06:01in about six months' time.
0:06:08 > 0:06:13Even life on a paradise island can have its limitations.
0:06:16 > 0:06:17MORE SCREECHING
0:06:18 > 0:06:21But at least she can't be far away.
0:06:26 > 0:06:32The world's entire population of pygmy sloths is isolated
0:06:32 > 0:06:35on a speck of land no bigger than New York's Central Park.
0:06:38 > 0:06:43The size of an island has a huge influence on the fate
0:06:43 > 0:06:45of those cast away there.
0:06:49 > 0:06:53The island of Komodo in Indonesia.
0:07:04 > 0:07:06Home to dragons.
0:07:23 > 0:07:28Ten feet long and weighing an impressive 150 lbs,
0:07:28 > 0:07:33these are the largest living lizards on the planet.
0:07:44 > 0:07:47It's unusual to find large predators on islands.
0:07:51 > 0:07:56Yet, for four million years, the Komodo dragon has dominated here.
0:08:06 > 0:08:09It might seem there wouldn't be enough food
0:08:09 > 0:08:12to support such giants on this relatively small island.
0:08:14 > 0:08:17But reptiles, being cold-blooded,
0:08:17 > 0:08:21need only about a tenth of the food a carnivorous mammal would.
0:08:25 > 0:08:28A single meal will last a dragon a month.
0:08:32 > 0:08:36There are so successful that their only serious competition comes from
0:08:36 > 0:08:38others of their own kind.
0:08:39 > 0:08:42And there are some 2,000 of them here.
0:09:05 > 0:09:11This giant, however, isn't looking for food - he's looking for a mate.
0:09:15 > 0:09:18Female dragons come into season only once a year.
0:09:29 > 0:09:30She's receptive.
0:09:38 > 0:09:40So far, so good.
0:09:45 > 0:09:47But he's strayed into someone else's patch.
0:09:53 > 0:09:58Another huge male thinks he is the king here.
0:10:03 > 0:10:05Space being limited on islands,
0:10:05 > 0:10:10dragon territories overlap and that creates continual conflict.
0:10:18 > 0:10:21In dragon society, size is everything.
0:10:36 > 0:10:41But if rivals are closely matched, the outcome can be uncertain.
0:10:48 > 0:10:52Muscular tails strike with the power of sledgehammers.
0:11:02 > 0:11:06And their serrated teeth are as sharp as steak knives.
0:11:18 > 0:11:20Each tries to topple his opponent.
0:11:41 > 0:11:43Defeated.
0:11:44 > 0:11:47Only the most powerful dragons
0:11:47 > 0:11:48win the right to mate.
0:11:57 > 0:12:01The limited food and space on small islands
0:12:01 > 0:12:03can often lead to intense competition.
0:12:04 > 0:12:07But some islands are immense.
0:12:08 > 0:12:10More like miniature continents.
0:12:11 > 0:12:17And these provide opportunities for life to experiment and evolve.
0:12:21 > 0:12:27Madagascar is one of the biggest islands and also one of the oldest,
0:12:27 > 0:12:32having split away from Africa over 120 million years ago.
0:12:43 > 0:12:45With time and isolation,
0:12:45 > 0:12:50its animals have adapted to take advantage of every available niche.
0:12:56 > 0:13:01The island now has some 250,000 different species,
0:13:01 > 0:13:04most found nowhere else on Earth.
0:13:16 > 0:13:19These are not monkeys, but lemurs.
0:13:25 > 0:13:29From a single ancestor, about 100 different types have evolved.
0:13:34 > 0:13:38The largest, the indri, seldom comes down from the branches.
0:13:46 > 0:13:50The much smaller ringtails wander in troops across the forest floor
0:13:50 > 0:13:51searching for food.
0:13:53 > 0:13:57And tiny bamboo lemurs eat nothing except bamboo.
0:14:05 > 0:14:09With few competitors, lemurs have been free to colonise
0:14:09 > 0:14:12almost every environment on the island.
0:14:14 > 0:14:17Even the most extreme.
0:14:24 > 0:14:28This baby sifaka has a hard life ahead of it.
0:14:33 > 0:14:36He's been born in the most arid and hostile corner
0:14:36 > 0:14:39of Madagascar's vast landscape.
0:14:41 > 0:14:45If he is to survive here, he has much to learn.
0:14:52 > 0:14:54The spiny forest is like a desert.
0:14:56 > 0:15:01It rarely rains, so water and food is very hard to find.
0:15:09 > 0:15:12Moving from tree to tree is a perilous business.
0:15:14 > 0:15:18Here, nearly all the plants are covered with ferocious spines.
0:15:20 > 0:15:24His mother searches the tree tops for the youngest leaves.
0:15:26 > 0:15:30They provide the only food and water to sustain the family.
0:15:36 > 0:15:40At three months old, the youngster is starting to explore.
0:15:46 > 0:15:49All too soon he will have to fend for himself up here.
0:15:55 > 0:15:59But it's altogether easier to stay on mother's back.
0:16:07 > 0:16:10If he can master the strange ways of this forest...
0:16:11 > 0:16:14..he will have a little corner of Madagascar to himself.
0:16:21 > 0:16:24Island life encourages animals to do things differently.
0:16:26 > 0:16:29And on some islands that is essential.
0:16:44 > 0:16:46There are islands still forming today...
0:16:47 > 0:16:49..built by volcanoes.
0:16:53 > 0:16:55Some erupt explosively.
0:17:02 > 0:17:04Others pour out rivers of molten rock.
0:17:06 > 0:17:07Lava.
0:17:13 > 0:17:14In the last 50 years,
0:17:14 > 0:17:17ten new volcanic islands have been formed.
0:17:45 > 0:17:50Newly created and often remote, they're hard for colonists to reach.
0:17:53 > 0:17:57Even those that do find these are tough places to survive.
0:18:03 > 0:18:08This is Fernandina, one of the Galapagos Islands in the Pacific.
0:18:10 > 0:18:15Young and still volcanically active, it's a desolate place.
0:18:29 > 0:18:33The surrounding sea, however, is particularly rich with life.
0:18:38 > 0:18:42And the frontier between these two very different worlds is the home of
0:18:42 > 0:18:44one of the strangest of reptiles.
0:18:49 > 0:18:51Seagoing iguanas.
0:18:54 > 0:18:55They are vegetarians,
0:18:55 > 0:18:58but since there's little food for them on the land,
0:18:58 > 0:19:01marine iguanas graze on the sea floor.
0:19:06 > 0:19:09A big male like this one can dive to 30 metres
0:19:09 > 0:19:11and hold his breath for half an hour.
0:19:37 > 0:19:42There are more than 7,000 individuals on Fernandina alone.
0:19:50 > 0:19:53And by bringing nutrients from the sea to the land,
0:19:53 > 0:19:56the iguanas help other animals to survive here, too.
0:20:00 > 0:20:03Crabs feed on dead skin on the iguana's back
0:20:03 > 0:20:07and, in turn, provide a welcome exfoliation service.
0:20:15 > 0:20:19While smaller lizards prey on the flies that pester the colony.
0:20:42 > 0:20:46But not all the relationships on this island are so harmonious.
0:20:53 > 0:20:55Marine iguanas lay their eggs in sand.
0:20:58 > 0:21:02In June, when the hatchlings emerge, they are vulnerable.
0:21:06 > 0:21:09They must join the adults at the edge of the sea.
0:21:09 > 0:21:12But the journey will be a dangerous one.
0:21:37 > 0:21:38Racer snakes.
0:22:08 > 0:22:10The snakes miss their chance.
0:22:18 > 0:22:21But more babies are hatching.
0:22:26 > 0:22:29And now the snakes are on the alert.
0:22:30 > 0:22:34This is the best feeding opportunity they will get all year.
0:22:50 > 0:22:55On flat ground, a baby iguana can outrun a racer snake.
0:22:56 > 0:22:58But others are waiting in ambush.
0:23:26 > 0:23:30Another hatchling has its first glimpse of a dangerous world.
0:24:28 > 0:24:33A snake's eyes aren't very good,
0:24:33 > 0:24:34but they can detect movement.
0:24:35 > 0:24:40So if the hatchling keeps its nerve, it may just avoid detection.
0:26:12 > 0:26:14A near miraculous escape.
0:26:21 > 0:26:25The lucky survivors can begin learning the unique way of life
0:26:25 > 0:26:27demanded by this hostile island.
0:26:36 > 0:26:39Although marine iguanas are expert swimmers,
0:26:39 > 0:26:41they can't cross open oceans.
0:26:50 > 0:26:55But even the stormiest waters are no barrier for birds.
0:27:05 > 0:27:10Gale force winds and cold temperatures make the sub-Antarctic
0:27:10 > 0:27:13islands off New Zealand particularly unwelcoming in winter.
0:27:26 > 0:27:32But, when the brief summer comes, temperatures rise and winds slacken.
0:27:48 > 0:27:51It's now that visitors arrive.
0:27:53 > 0:27:57All here to breed before winter returns.
0:27:59 > 0:28:01There's the Snares penguins.
0:28:10 > 0:28:12Shearwaters come, too.
0:28:14 > 0:28:18This is an excellent place for them to dig their nesting burrows,
0:28:18 > 0:28:21for no predators have managed to get here.
0:28:27 > 0:28:30Soon the island is crowded with birds.
0:28:32 > 0:28:36Every one of them eager to make the most of the short breeding season.
0:28:40 > 0:28:43But not everyone has a partner.
0:28:49 > 0:28:52A male Buller's albatross waits for his mate.
0:28:56 > 0:29:00Each year they spend six months apart, travelling the ocean.
0:29:05 > 0:29:08They reunite here to breed.
0:29:11 > 0:29:13But this year, she's late.
0:29:17 > 0:29:19No, that's not her.
0:29:23 > 0:29:25The other birds come and go.
0:29:36 > 0:29:37The clock is ticking.
0:29:38 > 0:29:40If she doesn't appear soon,
0:29:40 > 0:29:43it could be too late for them to breed successfully.
0:29:46 > 0:29:50Every morning the shearwaters fly off to collect food for their young.
0:30:08 > 0:30:11Everybody else seems to be getting on with it.
0:30:24 > 0:30:28The shearwaters' return marks another lost day.
0:30:30 > 0:30:35There are three million birds on the island, but only one matters to him.
0:30:43 > 0:30:44Could this be her?
0:30:51 > 0:30:52At last.
0:31:07 > 0:31:09At first, he's a little coy.
0:31:23 > 0:31:24But not for long.
0:31:32 > 0:31:35They greet each other with the special dance
0:31:35 > 0:31:37they've perfected over many years.
0:31:48 > 0:31:54There is much to do if they're to raise a chick before winter returns.
0:31:58 > 0:32:03But when you have been apart for six months, some things can't be rushed.
0:32:22 > 0:32:28Islands in warm tropical waters don't experience seasonal extremes.
0:32:31 > 0:32:35The Seychelles, lying off the coast of East Africa,
0:32:35 > 0:32:37provide a sanctuary for sea birds all the year round.
0:32:54 > 0:32:57Fairy terns are permanent residents.
0:32:59 > 0:33:03They take a fairly relaxed view about what constitutes a nest.
0:33:05 > 0:33:07A bare branch is quite enough.
0:33:16 > 0:33:20Climbing onto it to incubate has to be done with care.
0:33:29 > 0:33:32Once a year, the noddies arrive.
0:33:33 > 0:33:35They do make nests,
0:33:35 > 0:33:38and pisonia trees provide their young
0:33:38 > 0:33:41with a rather less precarious start in life.
0:33:47 > 0:33:50Nesting on this island looks idyllic.
0:33:51 > 0:33:55But behind the beauty, there's a sinister side.
0:34:00 > 0:34:05The Seychelles fody makes quick work of an unattended egg.
0:34:20 > 0:34:23She knows something's not quite right,
0:34:23 > 0:34:25but her drive to incubate is strong.
0:34:40 > 0:34:42The noddies too have a problem.
0:34:46 > 0:34:48As their chicks grow,
0:34:48 > 0:34:52so the pisonia trees develop seeds that are sticky
0:34:52 > 0:34:54and equipped with hooks.
0:34:59 > 0:35:01By the time the young noddies leave,
0:35:01 > 0:35:05they carry these hitchhiking seeds away to other islands.
0:35:12 > 0:35:16But sometimes the pisonia trees are too successful.
0:35:22 > 0:35:26If a fledgling, testing out its wings, drops to the ground,
0:35:26 > 0:35:28it can get covered with the seeds.
0:35:37 > 0:35:42Entangled and weighed down, if it can't free itself,
0:35:42 > 0:35:43the youngster will starve.
0:35:57 > 0:36:01The pisonia may have failed to disperse these seeds...
0:36:02 > 0:36:06..but it will soon have fertiliser for its roots.
0:36:12 > 0:36:18This is why some people call the pisonia the "bird catcher tree".
0:36:51 > 0:36:54The fairy tern laid another egg,
0:36:54 > 0:36:57and now she has a tiny chick to feed.
0:37:04 > 0:37:05This chick is lucky.
0:37:08 > 0:37:12By the time it fledges, the pisonia seeds will have dispersed,
0:37:12 > 0:37:14and the danger they brought will be gone.
0:37:26 > 0:37:30Even the most idyllic-looking of islands presents challenges
0:37:30 > 0:37:31for the animals living there.
0:37:33 > 0:37:37But the greatest threat they face is change.
0:37:53 > 0:37:55Christmas Island in the Indian Ocean.
0:37:57 > 0:37:59For millions of years,
0:37:59 > 0:38:03this remote speck of land has been ruled by crabs.
0:38:09 > 0:38:12Their ancestors came from the sea,
0:38:12 > 0:38:16but most have now adopted a land-based existence.
0:38:25 > 0:38:30Given there are so many of them, they get on relatively harmoniously.
0:38:32 > 0:38:38They're the gardeners and caretakers of a tiny crab utopia.
0:38:42 > 0:38:45Once a year, they must all return to the sea to breed,
0:38:45 > 0:38:47and the march of the red crabs
0:38:47 > 0:38:51is one of the greatest natural spectacles on earth.
0:39:03 > 0:39:05There are 50 million of them.
0:39:12 > 0:39:16It's an event that has brought the island worldwide fame.
0:39:27 > 0:39:29But in recent years,
0:39:29 > 0:39:33millions of red crabs haven't managed to reach the sea.
0:39:39 > 0:39:42An invader has occupied this island.
0:39:45 > 0:39:47Yellow crazy ants.
0:39:48 > 0:39:52They escaped from visiting ships and with no predators to control them,
0:39:52 > 0:39:57they have now created vast super colonies in the forest.
0:40:02 > 0:40:07When migrating red crabs march into their territory, the ants attack.
0:40:09 > 0:40:12Squirting acid into the crabs' eyes and mouths.
0:40:22 > 0:40:25The crabs have no defence.
0:40:28 > 0:40:30Blinded and confused...
0:40:31 > 0:40:32..they're doomed.
0:40:44 > 0:40:47Humans brought these ant invaders here,
0:40:47 > 0:40:50and now humans are having to control them.
0:40:54 > 0:40:59Isolated communities may evolve from millions of years in relative peace.
0:41:01 > 0:41:05But, when new challenges arrive, they can struggle to cope.
0:41:08 > 0:41:12Of all the species that have become extinct in recent years,
0:41:12 > 0:41:15around 80% have been islanders.
0:41:18 > 0:41:23Our impact on the Earth is greater today than ever before.
0:41:25 > 0:41:27Yet some islands are so remote
0:41:27 > 0:41:30that few humans have even set foot on them.
0:41:34 > 0:41:36Zavodovski Island is one.
0:41:40 > 0:41:43It lies in the great Southern Ocean.
0:41:43 > 0:41:46It's not only surrounded by the stormiest of seas,
0:41:46 > 0:41:49it is itself an active volcano.
0:41:52 > 0:41:55It's the last place on Earth you would choose to live.
0:42:04 > 0:42:07Unless you're a chinstrap penguin.
0:42:10 > 0:42:13There is plenty of food in these waters, but to exploit it,
0:42:13 > 0:42:15the penguins have to risk their lives.
0:43:04 > 0:43:08Life here is dangerous in the extreme.
0:43:22 > 0:43:24PENGUINS CHATTER
0:43:25 > 0:43:29But there are some benefits from living on a volcano.
0:43:31 > 0:43:35Its warmth melts the snow early in the year.
0:43:35 > 0:43:39And, by January, the Antarctic's mid-summer,
0:43:39 > 0:43:41the island is covered in chicks.
0:43:46 > 0:43:48Parents take turns at guarding them
0:43:48 > 0:43:51until they're large enough to be left alone.
0:43:56 > 0:44:01This mother's chicks are hungry, but she has no food left to give them.
0:44:03 > 0:44:07Their survival depends on their father returning with the next meal.
0:44:11 > 0:44:13But some don't make it.
0:44:27 > 0:44:31Skuas harass the colony, hoping to snatch a chick.
0:44:39 > 0:44:41She can't risk leaving them.
0:44:46 > 0:44:50Everything will be fine, as long as their father comes back soon.
0:45:19 > 0:45:24He's been fishing 50 miles offshore, but now he's not far away.
0:45:27 > 0:45:30For him, however, and for all the other parents here,
0:45:30 > 0:45:33the worst of the journey is still to come.
0:46:05 > 0:46:09Tiny claws help him to get whatever grip he can on the rough lava.
0:46:37 > 0:46:40For these commuters, it's rush hour.
0:46:42 > 0:46:44Some have had a really bad day.
0:46:49 > 0:46:53The father now has a two-mile walk to the nest,
0:46:53 > 0:46:55and a stomach loaded with food doesn't help.
0:47:02 > 0:47:06This is the largest penguin colony in the world.
0:47:13 > 0:47:16But as he makes the same journey every other day,
0:47:16 > 0:47:19he should be able to do it with his eyes closed.
0:47:28 > 0:47:31It's true that there can be safety in numbers,
0:47:31 > 0:47:34but numbers can also be something of a problem
0:47:34 > 0:47:36when you're trying to find your own nest.
0:47:43 > 0:47:45The mother is still waiting.
0:47:47 > 0:47:49Her chicks are now desperate.
0:47:49 > 0:47:50THEY CHEEP
0:47:55 > 0:47:57In the midst of all this deafening chorus,
0:47:57 > 0:47:59he can recognise her particular cry.
0:48:19 > 0:48:21At last.
0:48:36 > 0:48:38Both chicks will get a meal.
0:48:45 > 0:48:50With a head bob of acknowledgement, their mother now leaves.
0:48:50 > 0:48:53It's her turn to do the feeding run.
0:48:59 > 0:49:06This formidable commute is the price these penguins pay for sanctuary.
0:49:12 > 0:49:15A strange vision of paradise to us, perhaps,
0:49:15 > 0:49:21but, for one and a half million penguins, this island has it all.
0:49:32 > 0:49:36Islands may seem remote and insignificant,
0:49:36 > 0:49:40but they are home to some of the most precious wildlife on Earth.
0:50:03 > 0:50:06The expedition to film on the island of Zavodovski
0:50:06 > 0:50:09was the most intrepid shoot of the series.
0:50:10 > 0:50:13To ensure its success, the team have called in
0:50:13 > 0:50:16Antarctic expert Jerome Poncet,
0:50:16 > 0:50:19one of the few people to have set foot on the island.
0:50:21 > 0:50:25This whole region of Antarctica is rarely visited.
0:50:29 > 0:50:32And this is the planet's roughest ocean.
0:50:41 > 0:50:43After seven long days and nights at sea,
0:50:43 > 0:50:46they get their first glimpse of the final destination.
0:50:46 > 0:50:49It's actually quite surreal after a whole year,
0:50:49 > 0:50:51trying to put the expedition together.
0:50:51 > 0:50:53And then today we wake up, and there's the volcano.
0:50:53 > 0:50:55That's Zavodovski.
0:50:56 > 0:50:59The explorers who discovered this place
0:50:59 > 0:51:02spoke of the stench of sulphurous gases,
0:51:02 > 0:51:05treacherous waters,
0:51:05 > 0:51:07and astonishing numbers of penguins.
0:51:11 > 0:51:13It seems not much has changed.
0:51:15 > 0:51:17Jerome's been round the whole place,
0:51:17 > 0:51:20and there literally is only one safe area to get on,
0:51:20 > 0:51:21and he's telling us
0:51:21 > 0:51:23it's that rock face over there.
0:51:26 > 0:51:29The team must take everything they need to survive.
0:51:30 > 0:51:31There are the penguins!
0:51:34 > 0:51:35Though the boat'll stay nearby,
0:51:35 > 0:51:37they will need to be self-sufficient.
0:51:38 > 0:51:42But that means taking a tonne of equipment up this cliff.
0:51:42 > 0:51:45Just get to that lot to help.
0:51:45 > 0:51:46Many flippers make light work.
0:51:49 > 0:51:51They work all day getting the gear ashore.
0:51:54 > 0:51:58But the fact there are so many penguins on the island
0:51:58 > 0:51:59doesn't make it easy.
0:52:00 > 0:52:03The hardest thing for us has been finding a pathway through,
0:52:03 > 0:52:06because there's absolutely penguins everywhere you look.
0:52:13 > 0:52:16Finally, it's time to make camp.
0:52:21 > 0:52:24They choose a sheltered place that won't disturb the locals.
0:52:26 > 0:52:30But since most of the penguins won't have seen a human being before,
0:52:30 > 0:52:32they seem keen to pop over and visit.
0:52:33 > 0:52:36- Hello.- Nosy neighbours.
0:52:38 > 0:52:39The team set off
0:52:39 > 0:52:42to start documenting the daily lives of the penguins,
0:52:42 > 0:52:45and what they find is astonishing.
0:52:46 > 0:52:49As soon as you walk over that ridge, you sort of get a tingly feeling,
0:52:49 > 0:52:54because I've never seen that many animals in one spot.
0:52:54 > 0:52:55It's mind-blowing.
0:52:57 > 0:53:00It's like Glastonbury Festival.
0:53:00 > 0:53:01The whole landscape
0:53:01 > 0:53:05is full of little black and white penguins waddling around.
0:53:09 > 0:53:12This is penguin paradise, and that's what we're trying to show.
0:53:17 > 0:53:18A promising start.
0:53:20 > 0:53:23But here, fortunes can change quickly.
0:53:27 > 0:53:29# Summertime... #
0:53:32 > 0:53:35Every season within ten minutes.
0:53:38 > 0:53:42As the snow melts, it creates an unforeseen problem.
0:53:44 > 0:53:46We purposely chose this campsite
0:53:46 > 0:53:49because it was a place where the penguins didn't seem to go.
0:53:49 > 0:53:52I think we've realised why the penguins don't nest here.
0:53:52 > 0:53:55It's because of the spray and because of some run-off,
0:53:55 > 0:53:58so we are literally in a bit of a bog.
0:53:59 > 0:54:01And it's not just mud.
0:54:03 > 0:54:07A couple of these guys, as they wander down to do a spot of fishing,
0:54:07 > 0:54:11they tend to use my tent as a little poop spot.
0:54:11 > 0:54:13You kind of get used to it at night,
0:54:13 > 0:54:16just hearing a constant splat on top of the tent.
0:54:16 > 0:54:20But, as you can see, all of the kit,
0:54:20 > 0:54:23I'm afraid that's getting splat on as well.
0:54:23 > 0:54:27And, when the wind changes, it brings a noxious reminder
0:54:27 > 0:54:30that they're camping on an active volcano.
0:54:32 > 0:54:35It's the first time we've smelt sulphur,
0:54:35 > 0:54:38which is welcome relief from smelling penguins.
0:54:38 > 0:54:39It's smoking away.
0:54:41 > 0:54:44I think if they start running for the sea,
0:54:44 > 0:54:47we're going to be calling Jerome pretty quick for the boat.
0:54:49 > 0:54:54Each day filming on Zavodovski seems to present a new challenge.
0:54:58 > 0:55:01Next, a huge storm hits the island.
0:55:04 > 0:55:06Only now do the team realise
0:55:06 > 0:55:09just how tough life can be for the penguins.
0:55:13 > 0:55:16It's hard not to be moved by the effort they go to
0:55:16 > 0:55:18to feed their chicks.
0:55:20 > 0:55:22These huge waves are coming in.
0:55:22 > 0:55:24The penguins are surfing here,
0:55:24 > 0:55:26getting battered on these big boulders.
0:55:26 > 0:55:29Now and then you just get a penguin that gets catapulted
0:55:29 > 0:55:3215 metres in the air - it's totally ludicrous.
0:55:34 > 0:55:38And really, I think there are quite a few penguins getting killed in it.
0:55:43 > 0:55:48The beach in the afternoon was just a scene of death and destruction.
0:55:50 > 0:55:51It was absolute carnage.
0:55:54 > 0:55:55It was heartbreaking.
0:55:55 > 0:55:58I mean, they're trying so hard to get up the beach with broken legs
0:55:58 > 0:56:02and bleeding and very, you know, sobering, really.
0:56:06 > 0:56:10After witnessing the struggles, the penguins must endure,
0:56:10 > 0:56:12the team now face the same problem.
0:56:13 > 0:56:14Getting off the island.
0:56:16 > 0:56:20With another storm coming in, they decide to take their chance.
0:56:22 > 0:56:26Jerome has seconds to get in and out between the waves.
0:56:27 > 0:56:28Or the Zodiac could tip...
0:56:30 > 0:56:31..leaving them all stranded.
0:56:32 > 0:56:35Hurray, that's the first box off the island.
0:56:40 > 0:56:44What took a day to get ashore must be off in minutes.
0:56:44 > 0:56:46And the swell is getting bigger.
0:56:48 > 0:56:50Their window of opportunity is closing.
0:56:52 > 0:56:54Look at this swell now, watch out, watch out!
0:57:00 > 0:57:04The equipment's off, but now the team has to follow.
0:57:09 > 0:57:11She's just leaving us now, is she?
0:57:11 > 0:57:14That's the producer, she's gone! We have to swim now.
0:57:16 > 0:57:17- They're gone.- Yeah.
0:57:19 > 0:57:21Luckily it didn't come to that.
0:57:25 > 0:57:31Safely aboard, they leave with an unforgettable experience
0:57:31 > 0:57:35of how hard life is on an island at the edge of the world.
0:57:40 > 0:57:45Next time, we ascend into the planet's highest peaks
0:57:45 > 0:57:48to discover a spectacular but hostile world,
0:57:48 > 0:57:51where only the toughest animals can endure.
0:57:54 > 0:57:57This is life on the roof of the world.
0:57:57 > 0:57:58Mountains.