0:00:02 > 0:00:05The sun rises on Japan.
0:00:07 > 0:00:10More than 6,000 islands on the edge of the Pacific.
0:00:16 > 0:00:20Life here is at the mercy of Earth's most powerful elemental forces.
0:00:27 > 0:00:30From the wilds of the frozen north...
0:00:32 > 0:00:33BIRDS SQUAWK
0:00:33 > 0:00:36..to the subtropical warmth of the south.
0:00:39 > 0:00:42Animals along this chain of islands have had to adapt
0:00:42 > 0:00:44in unique and sometimes bizarre ways.
0:00:52 > 0:00:53Throughout this land,
0:00:53 > 0:00:56people have developed an extraordinary relationship
0:00:56 > 0:00:58with the natural world.
0:00:58 > 0:01:01BEAR GROWLS
0:01:07 > 0:01:09Trying to capture its fleeting beauty...
0:01:13 > 0:01:15..and tame its spirit.
0:01:16 > 0:01:20But these islands remain wild, mysterious and magical.
0:01:22 > 0:01:25This is Japan.
0:01:25 > 0:01:28BIRDS SQUAWK
0:01:32 > 0:01:36In Japan's far south, there's a chain of tiny islands
0:01:36 > 0:01:39stretching for 750 miles towards the tropics.
0:01:42 > 0:01:46Isolated in the vast Pacific Ocean,
0:01:46 > 0:01:48these islands are ruled by the sea.
0:01:57 > 0:02:00Here, you have to live life with a different spirit.
0:02:03 > 0:02:05And the further south you go...
0:02:05 > 0:02:07the stranger life seems to become.
0:02:10 > 0:02:13SHE SPEAKS JAPANESE
0:02:25 > 0:02:29At the top of the chain lies the island of Yakushima.
0:02:36 > 0:02:40A narrow channel is all that separates it from the mainland.
0:02:42 > 0:02:44It's like a lost world.
0:02:53 > 0:02:57Its steep slopes are mostly covered in forest
0:02:57 > 0:03:00and some of the trees are thousands of years old.
0:03:11 > 0:03:13A family of Japanese macaques.
0:03:15 > 0:03:18They share this island with another animal...
0:03:19 > 0:03:20..sika deer.
0:03:31 > 0:03:33Deer and macaques live all over Japan...
0:03:35 > 0:03:40..but here on Yakushima, the two species live side-by-side.
0:03:44 > 0:03:48And the rowdier young monkeys do something very unusual.
0:03:55 > 0:03:58They ride on the deers' backs.
0:04:01 > 0:04:03MACAQUE SQUEAKS
0:04:13 > 0:04:17Why they do it, and why the deer put up with it, is not entirely clear...
0:04:21 > 0:04:23..but it only happens here on Yakushima.
0:04:30 > 0:04:33There comes a point when the deer have had enough.
0:04:35 > 0:04:37MACAQUE SQUEAKS
0:04:43 > 0:04:46But there are advantages to hanging out with monkeys.
0:04:55 > 0:04:58Every day, the macaques forage up in the trees.
0:04:59 > 0:05:05The deer listen for their feeding calls and follow them around,
0:05:05 > 0:05:06picking up what they drop.
0:05:08 > 0:05:10It's food they could never reach themselves.
0:05:21 > 0:05:23It's an easy-going relationship.
0:05:24 > 0:05:28But even the best of friends can fall out over something trivial,
0:05:28 > 0:05:30like a stolen leaf.
0:05:30 > 0:05:31MACAQUE SQUEALS
0:05:37 > 0:05:38MACAQUE SQUEALS
0:05:43 > 0:05:48No-one really knows why these two animals have such a close bond...
0:05:51 > 0:05:52..but strange things can happen
0:05:52 > 0:05:55when you are cast away on isolated islands.
0:06:04 > 0:06:07Enormous volcanic forces created Yakushima
0:06:07 > 0:06:09and many of the islands beyond it.
0:06:18 > 0:06:22The sea level rose and Yakushima was cut off from the rest of Japan.
0:06:29 > 0:06:31The deer and the macaques were marooned together
0:06:31 > 0:06:33in this odd little world,
0:06:33 > 0:06:35where life could follow different rules.
0:06:47 > 0:06:51This part of Japan lies along a great rift in the Earth's crust.
0:06:52 > 0:06:56It's one of the most geologically unstable places in the world.
0:07:01 > 0:07:04It has 18 active volcanoes.
0:07:10 > 0:07:12VOLCANO RUMBLES
0:07:19 > 0:07:21Some of the largest in the world.
0:07:29 > 0:07:31VOLCANO RUMBLES
0:07:41 > 0:07:44Sakurajima is Japan's most active volcano.
0:07:44 > 0:07:46VOLCANO RUMBLES
0:07:47 > 0:07:51It has been erupting nonstop for the last 60 years.
0:08:00 > 0:08:04Even so, over half a million people live next to this smoking giant,
0:08:04 > 0:08:08never quite sure when it might get really violent.
0:08:08 > 0:08:09BIRD CAWS
0:08:13 > 0:08:15VOLCANO RUMBLES
0:08:21 > 0:08:25Every few weeks, it belches out thousands of tonnes of ash,
0:08:25 > 0:08:26covering the city.
0:08:44 > 0:08:47It might not seem like the ideal place to live...
0:08:48 > 0:08:53..but with a few simple precautions, life can be almost normal.
0:09:00 > 0:09:03Rocks the size of tennis balls can rain down at any time.
0:09:05 > 0:09:07It gives the school run an element of peril...
0:09:09 > 0:09:11..but these children are used to it.
0:09:26 > 0:09:28JAPANESE SPOKEN OVER TANNOY
0:09:35 > 0:09:37The school day always begins
0:09:37 > 0:09:40with a sweep-up of last night's shower of ash.
0:09:45 > 0:09:49Despite the risks, people have been living in the shadow of Sakurajima
0:09:49 > 0:09:51for thousands of years...
0:09:51 > 0:09:53but there are advantages.
0:09:56 > 0:10:00The volcanic soil is fertile and farms crowd the lower slopes...
0:10:02 > 0:10:05..but the volcanic warmth brings unexpected benefits.
0:10:08 > 0:10:11On this local beach, nobody goes swimming.
0:10:12 > 0:10:14The water could kill you.
0:10:17 > 0:10:18It's hot enough to brew tea.
0:10:24 > 0:10:28There's not much life in the sea around here,
0:10:28 > 0:10:31but the resourceful people of this island have found a way
0:10:31 > 0:10:33to create a paradise.
0:10:42 > 0:10:44A steaming sand bath.
0:10:53 > 0:10:55People travel from all over Japan
0:10:55 > 0:10:58to be buried up to their necks in hot sand.
0:11:00 > 0:11:02They've been doing it for hundreds of years.
0:11:09 > 0:11:13They say it improves circulation, and restores health and vitality.
0:11:18 > 0:11:21If nothing else, it's a nice lie down.
0:11:32 > 0:11:34When you live next to a volcano,
0:11:34 > 0:11:37you might have to deal with its dangers,
0:11:37 > 0:11:39but you can still relish its delights.
0:11:45 > 0:11:47Heading south along Japan's island chain,
0:11:47 > 0:11:51life becomes more and more influenced by the sea.
0:11:56 > 0:11:58It brings something to these islands
0:11:58 > 0:12:00that affects everything that lives here.
0:12:07 > 0:12:09The Kuroshio Current -
0:12:09 > 0:12:13one of the most powerful ocean currents in the world.
0:12:14 > 0:12:16Japan's own Gulf Stream.
0:12:18 > 0:12:20It surges up from the equator
0:12:20 > 0:12:24and delivers 50 million tonnes of warm water every second...
0:12:28 > 0:12:31..and brings a touch of tropical magic...
0:12:44 > 0:12:47..creating the perfect conditions for coral reefs.
0:12:58 > 0:13:01It's only the warmth of the Kuroshio Current
0:13:01 > 0:13:05that allows coral to grow this far north in the Pacific Ocean.
0:13:16 > 0:13:19The current also brings nutrients from the deep.
0:13:37 > 0:13:42There's one very small resident who never strays far from the reef.
0:13:42 > 0:13:45He's a bluestreak cleaner wrasse...
0:13:45 > 0:13:47and he leads a very busy life.
0:13:55 > 0:13:59He eats parasites and dead skin from other fish...
0:14:00 > 0:14:03..but he has to wait for them to come his way.
0:14:07 > 0:14:09And right now, no-one is stopping long enough
0:14:09 > 0:14:11to give him as much as a nibble.
0:14:23 > 0:14:26But then he spots something worth chasing...
0:14:30 > 0:14:31..a batfish.
0:14:38 > 0:14:42Like a customer at a spa, the batfish lies back
0:14:42 > 0:14:43and waits for attention.
0:14:46 > 0:14:47It opens its gills
0:14:47 > 0:14:51and the cleaner wrasse bustles in to begin the treatment.
0:14:56 > 0:15:00The batfish even changes colour...
0:15:00 > 0:15:03probably to make parasites more visible.
0:15:08 > 0:15:11Someone else has arrived at the reef.
0:15:12 > 0:15:14The batfish is abandoned.
0:15:19 > 0:15:21There's a visitor from the open ocean
0:15:21 > 0:15:24that's worth dropping everything for.
0:15:32 > 0:15:36A manta ray, two metres long,
0:15:36 > 0:15:39has come back to a favourite stretch of reef.
0:15:52 > 0:15:55He signals to the manta by flicking his tail...
0:15:59 > 0:16:03..and the giant responds by unfurling itself for cleaning.
0:16:09 > 0:16:13The manta keeps its feeding lobes rolled up while it swims...
0:16:18 > 0:16:21..but a thorough clean keeps them parasite-free.
0:16:40 > 0:16:43This enormous fish would never visit Japan
0:16:43 > 0:16:48if it wasn't for the warmth that bathes the island chain...
0:16:48 > 0:16:51and the helpful services of this resourceful little wrasse.
0:16:57 > 0:17:01The Kuroshio Current brings more dangerous animals to the islands.
0:17:17 > 0:17:18Sea snakes.
0:17:20 > 0:17:24At one time, these snakes' ancestors lived on dry land.
0:17:25 > 0:17:27They must still visit the surface to breathe.
0:17:33 > 0:17:36But they are beautifully adapted to life at sea,
0:17:36 > 0:17:39hunting for fish around the island reefs.
0:17:45 > 0:17:48They have some of the most toxic venom of any animal,
0:17:48 > 0:17:50so they don't have many predators.
0:17:54 > 0:17:57But as they forage off the coast of one small island,
0:17:57 > 0:18:00their greatest nemesis is approaching.
0:18:14 > 0:18:19Yoko and Setsuko are hunters and they have a fearsome reputation.
0:18:24 > 0:18:28These two 70-year-olds are on a shopping trip like no other.
0:18:37 > 0:18:40Yoko and Setsuko live on the tiny island of Kudaka.
0:18:43 > 0:18:47It's only three miles across and, with limited space on land,
0:18:47 > 0:18:50the locals look to the sea to provide.
0:19:05 > 0:19:08As the sun sets, the ladies' prey is approaching.
0:19:18 > 0:19:20On certain summer nights,
0:19:20 > 0:19:23venomous sea snakes move towards the island
0:19:23 > 0:19:25and gather in coastal caves...
0:19:27 > 0:19:30..looking for shelter and fresh water to drink.
0:19:39 > 0:19:43But coming ashore on this island is extremely risky.
0:20:06 > 0:20:10It takes some nerve to wade in with no protective clothing.
0:20:12 > 0:20:16Sea snake venom can be ten times more powerful than a rattlesnake's.
0:20:37 > 0:20:40Yoko has been hunting snakes for 40 years.
0:20:40 > 0:20:43It's a skill that's been passed down
0:20:43 > 0:20:46the generations here for at least five centuries.
0:21:23 > 0:21:26The snakes will be dried in this smokehouse
0:21:26 > 0:21:29using a secret process known only by the hunters.
0:21:37 > 0:21:39Then they go into a special soup.
0:21:45 > 0:21:49The catching and eating of sea snakes is a very old tradition
0:21:49 > 0:21:53on the island of Kudaka, where the sea provides more than the land.
0:21:55 > 0:21:56THEY SPEAK JAPANESE
0:22:00 > 0:22:05It's part of a rich island culture that goes back many centuries.
0:22:11 > 0:22:16Kudaka is just off the bigger island of Okinawa,
0:22:16 > 0:22:18right in the centre of the island chain.
0:22:26 > 0:22:30The seas are warm and bountiful, and the climate is perfect.
0:22:39 > 0:22:42In the Okinawan village of Ogimi,
0:22:42 > 0:22:44you are still considered young at 80.
0:22:46 > 0:22:48Many people here live well beyond 100.
0:23:03 > 0:23:07Okinawa is famous as a place where people live longer,
0:23:07 > 0:23:10an achievement worth celebrating.
0:23:30 > 0:23:3396-year-old Sumiko reckons it's all about staying active.
0:23:35 > 0:23:37She cycles to her vegetable garden every day.
0:23:41 > 0:23:44Others have their own theories.
0:23:50 > 0:23:52THEY LAUGH
0:23:52 > 0:23:57But the biggest influence of all, they say, is the Okinawan diet.
0:23:57 > 0:23:59Maybe this is what keeps them young.
0:24:10 > 0:24:13But there's one ingredient in their diet that can't be grown on land.
0:24:15 > 0:24:18It's another gift from the bountiful sea.
0:24:24 > 0:24:27Around Okinawa, the warm Kuroshio Current supports
0:24:27 > 0:24:30one of the strangest ways of farming in the world.
0:24:38 > 0:24:42The Tsuhako family have made their living from the sea for generations.
0:25:06 > 0:25:08It's harvest time on the family farm.
0:25:08 > 0:25:10ENGINE RUMBLES
0:25:32 > 0:25:34This is a field of mozuku.
0:25:36 > 0:25:38It's just humble seaweed,
0:25:38 > 0:25:41but it has a reputation as a miracle super food.
0:25:48 > 0:25:49It grows naturally,
0:25:49 > 0:25:53but Okinawan farmers have set out an ingenious system of nets
0:25:53 > 0:25:55to help it take root...
0:25:56 > 0:25:59..and they have a very practical way of harvesting it.
0:26:12 > 0:26:16Mozuku seaweed is one of the most sought-after dishes in all Japan...
0:26:18 > 0:26:20..so every strand is precious.
0:26:31 > 0:26:34This farming still relies on traditional Japanese wisdom.
0:26:36 > 0:26:39It's what they call satoumi.
0:26:40 > 0:26:42If you work harmoniously with nature,
0:26:42 > 0:26:44the sea will always provide.
0:26:49 > 0:26:52This is a man-made environment...
0:26:52 > 0:26:55but strange creatures roam the mozuku beds.
0:26:59 > 0:27:03Sea slugs. Some crawl...
0:27:04 > 0:27:06..while others fly.
0:27:19 > 0:27:24This harmonious way of farming only works if the conditions are perfect.
0:27:26 > 0:27:31Warm water, plenty of nutrients...
0:27:31 > 0:27:33and a wide, shallow sea.
0:27:42 > 0:27:47It's only here in Okinawa that they can grow mozuku
0:27:47 > 0:27:49on such a massive scale.
0:28:05 > 0:28:07On these central islands,
0:28:07 > 0:28:11the bountiful sea provides a charmed way of life.
0:28:17 > 0:28:20But further south, life takes a different turn.
0:28:25 > 0:28:29Islands become further apart in the vastness of the ocean.
0:28:36 > 0:28:38With fewer human inhabitants,
0:28:38 > 0:28:43these are some of Japan's most remote island outposts.
0:28:48 > 0:28:51Increasing isolation brings a whole new set of challenges...
0:28:54 > 0:28:57..and life has found ever more inventive ways to get by.
0:29:10 > 0:29:12One-and-a-half million years ago,
0:29:12 > 0:29:15the island of Iriomote was joined to the mainland.
0:29:20 > 0:29:25When sea levels rose and cut it off, one animal was left stranded here.
0:29:34 > 0:29:36Its descendants have been scratching a living in the island's
0:29:36 > 0:29:39dense forests ever since.
0:29:49 > 0:29:51A Ryukyu wild boar.
0:29:53 > 0:29:56It spends its day grubbing through the forest soils,
0:29:56 > 0:29:58digging up worms and roots,
0:29:58 > 0:30:00just like wild boar the world over.
0:30:04 > 0:30:07But life on this island is not always easy.
0:30:09 > 0:30:11It might look like paradise,
0:30:11 > 0:30:14but sometimes it's a struggle to find enough to eat.
0:30:26 > 0:30:28In the face of hardship,
0:30:28 > 0:30:31something remarkable happened to the Ryukyu wild boar.
0:30:33 > 0:30:35Over the generations, it has shrunk
0:30:35 > 0:30:37to half the size of its mainland cousins.
0:30:40 > 0:30:43When you're small, you need less energy to survive.
0:30:49 > 0:30:53They're now just knee-high - the tiniest wild boar in the world.
0:30:58 > 0:31:01But it still has a phenomenal sense of smell.
0:31:04 > 0:31:05BOAR SNIFFS
0:31:11 > 0:31:13It's alerted this little pig to a valuable bounty.
0:31:28 > 0:31:31A female green turtle has come back to the very beach
0:31:31 > 0:31:33where she was born.
0:31:36 > 0:31:37She's here to lay her eggs.
0:31:51 > 0:31:53Then she's off, back to the sea.
0:32:10 > 0:32:12A heavily pregnant and very hungry sow
0:32:12 > 0:32:15has come to the beach looking for eggs.
0:32:21 > 0:32:23But she's not the only one.
0:32:25 > 0:32:27A male is already rifling the nest.
0:32:37 > 0:32:40He certainly won't let her share.
0:32:40 > 0:32:42She can only eat when he's had his fill.
0:32:50 > 0:32:51BIRD CAWS
0:32:57 > 0:33:00But each nest can contain more than 100 eggs...
0:33:01 > 0:33:03..so there's enough to go around.
0:33:14 > 0:33:16Cast away on these remote islands,
0:33:16 > 0:33:19you have to be extra resourceful to survive.
0:33:28 > 0:33:32On the tiniest islands, the challenges get more extreme.
0:33:34 > 0:33:37These are places where even pint-sized pigs can't survive.
0:33:39 > 0:33:41Islands like Tarama have been overrun
0:33:41 > 0:33:43by very different life forms...
0:33:45 > 0:33:46..creatures of the sea.
0:33:54 > 0:33:57Blueberry hermit crabs,
0:33:57 > 0:34:01tropical crabs that have settled on these little islands.
0:34:11 > 0:34:13These crabs don't grow shells of their own.
0:34:13 > 0:34:17They make do with cast-offs from other sea creatures
0:34:17 > 0:34:20and they can only grow as big as their borrowed shell will allow.
0:34:23 > 0:34:26Deep in the forest, there's a very different crab...
0:34:29 > 0:34:31..one that only comes out at night.
0:34:43 > 0:34:45A robber crab...
0:34:45 > 0:34:48the largest land crab in the world.
0:34:51 > 0:34:54On these islands, before people arrived,
0:34:54 > 0:34:58there were no big mammals and a humble crab could become king.
0:35:03 > 0:35:05They've become giants.
0:35:14 > 0:35:19Some can live for 60 years and grow to nearly a metre across.
0:35:23 > 0:35:25This female is only about 12 years old...
0:35:27 > 0:35:29..so she still has a way to go
0:35:29 > 0:35:32before she's a true colossus of the crab world.
0:35:34 > 0:35:37But right now, she has a more pressing challenge.
0:35:39 > 0:35:41For several weeks, she's been nurturing
0:35:41 > 0:35:43thousands of eggs under her tail.
0:35:49 > 0:35:53But her babies need to start their lives in the ocean...
0:35:56 > 0:35:57..so this young mum needs to make
0:35:57 > 0:36:00the most important journey of her life...
0:36:02 > 0:36:05..and there are some very modern obstacles in her way.
0:36:09 > 0:36:12CAR RUMBLES
0:36:12 > 0:36:14DOG BARKS
0:36:14 > 0:36:17There's a small village between her forest home and the ocean.
0:36:23 > 0:36:25She must get to the sea in time
0:36:25 > 0:36:27for one of the highest tides of the year.
0:36:43 > 0:36:47But when she reaches the shore, she faces a dangerous situation.
0:36:55 > 0:36:58Robber crabs have become so big and heavy they can't swim.
0:37:07 > 0:37:09She needs to summon her nerve
0:37:09 > 0:37:12and wade out far enough to release her precious eggs.
0:37:14 > 0:37:17If she gets swept away, she'll drown.
0:37:28 > 0:37:30She's done it.
0:37:30 > 0:37:33She can get back to the safety of dry land...
0:37:35 > 0:37:37..leaving her eggs to hatch in the warmth of the sea.
0:37:46 > 0:37:48But all this warmth comes at a price.
0:37:52 > 0:37:55Every summer, these Japanese islands
0:37:55 > 0:37:58are swept by violent tropical storms.
0:38:01 > 0:38:06They're born far out to sea and some grow into typhoons.
0:38:08 > 0:38:09The hurricanes of the Pacific.
0:38:15 > 0:38:17They draw energy from the warmth of the tropical sea
0:38:17 > 0:38:20and their power is enormous.
0:38:23 > 0:38:26If you're going to survive, you have to be fully prepared.
0:38:32 > 0:38:36Over thousands of years, people have built up defences.
0:38:37 > 0:38:40They've designed homes with high walls and sturdy roofs.
0:38:47 > 0:38:50Houses are decorated with Shisa lion dogs,
0:38:50 > 0:38:54ready to ward off evil spirits and impending disaster.
0:38:58 > 0:38:59All along the southwest islands,
0:38:59 > 0:39:04people and animals batten down the hatches as the storms build.
0:39:15 > 0:39:18In the forests, the macaques run for cover
0:39:18 > 0:39:19and huddle together for safety.
0:39:32 > 0:39:35But at the most south-westerly point of the island chain,
0:39:35 > 0:39:39one animal has come up with a more ingenious survival strategy.
0:39:44 > 0:39:48Yonaguni, 750 miles from the mainland,
0:39:48 > 0:39:52and often the first island to feel the full force of a typhoon.
0:40:04 > 0:40:09This far-flung speck of land is home to a very resourceful caterpillar.
0:40:27 > 0:40:28THUNDER RUMBLES
0:40:36 > 0:40:39It has built a typhoon-resistant shelter...
0:40:40 > 0:40:44..an ingenious design of leaves and silk,
0:40:44 > 0:40:47woven together into a perfect defence against wind and rain.
0:40:55 > 0:41:00When they hit land, typhoon winds can reach 150mph.
0:42:14 > 0:42:16The giant cocoon has withstood the elements.
0:42:50 > 0:42:52The caterpillar has been transformed
0:42:52 > 0:42:55into one of the most striking animals on earth...
0:43:01 > 0:43:02..an Atlas moth.
0:43:09 > 0:43:12She has a wingspan the size of a dinner plate.
0:43:14 > 0:43:16The largest moth in the world.
0:43:20 > 0:43:22Now that the typhoons have passed,
0:43:22 > 0:43:27she's come out for one purpose only - to attract a mate.
0:43:28 > 0:43:31She gives off pheromones from her tail.
0:43:36 > 0:43:38A male has picked up her scent.
0:43:49 > 0:43:51He'll fly three miles to find her.
0:44:03 > 0:44:06Once they've mated, their job is done.
0:44:08 > 0:44:11They don't even have mouths, so they will never eat.
0:44:22 > 0:44:24They only have a few days to live...
0:44:26 > 0:44:29..but they have defeated the typhoon.
0:44:39 > 0:44:42This is a place of extreme survival,
0:44:42 > 0:44:46where the ocean, in all its moods, drives everything.
0:44:59 > 0:45:04Nowhere is that more evident than at the very furthest extent of Japan.
0:45:15 > 0:45:18Just below the surface lies a great mystery.
0:45:24 > 0:45:28The waters around Yonaguni are so remote,
0:45:28 > 0:45:31they've only been explored in the last few decades.
0:45:56 > 0:46:01In 1986, a local diver discovered something totally unexpected.
0:46:06 > 0:46:09He noticed strange features in the rock.
0:46:15 > 0:46:19He saw straight lines and flat surfaces.
0:46:30 > 0:46:34Here was what looked like a colossal underwater monument.
0:46:38 > 0:46:45A terraced sandstone pyramid, 270 metres long and 25 metres high.
0:46:53 > 0:46:56But who or what could have made it?
0:47:05 > 0:47:08Were those steps created for people to walk on?
0:47:15 > 0:47:18Some now believe these lines and surfaces
0:47:18 > 0:47:20were formed by nature alone.
0:47:26 > 0:47:28The simple shearing of rock
0:47:28 > 0:47:31in an area known for tremors and earthquakes.
0:47:34 > 0:47:37But others are convinced that this is a monument
0:47:37 > 0:47:39built by a lost civilisation...
0:47:42 > 0:47:45..10,000 years ago, when sea levels were lower.
0:47:47 > 0:47:50If it is, this Atlantis of the Pacific
0:47:50 > 0:47:53would rewrite the history of these islands.
0:48:03 > 0:48:05We may never know the truth.
0:48:11 > 0:48:14But whether it was shaped by a lost civilisation
0:48:14 > 0:48:16or immense forces of nature,
0:48:16 > 0:48:20in the end, it was swallowed by the rising sea.
0:48:27 > 0:48:31All along this chain of islands, the sea is ultimately in control.
0:48:37 > 0:48:41But life has adapted to its fickle ways...
0:48:41 > 0:48:44making the most of opportunities while it can.
0:49:03 > 0:49:06We're in a cave by the sea.
0:49:06 > 0:49:09There's a 70-year-old lady down there catching sea snakes...
0:49:12 > 0:49:14..with her bare hands!
0:49:17 > 0:49:19One of the team's more unusual experiences
0:49:19 > 0:49:23was on the island of Kudaka filming sea snake hunting.
0:49:30 > 0:49:34A privileged insight into the lives of two extraordinary women...
0:49:36 > 0:49:38..who maintain an ancient tradition.
0:49:48 > 0:49:50The tiny island of Kudaka is just a short ferry ride
0:49:50 > 0:49:52from the main island of Okinawa.
0:49:54 > 0:49:58Producer David Marks and cameraman Robin Cox are keen to meet
0:49:58 > 0:50:00one of the island's legendary snake hunters...
0:50:02 > 0:50:04..72-year-old Yoko Fukuchi.
0:50:04 > 0:50:05THEY SPEAK JAPANESE
0:50:13 > 0:50:15"You're very cute," that's what she's saying.
0:50:18 > 0:50:20It's a very quiet island.
0:50:20 > 0:50:22Fewer than 200 people live here.
0:50:26 > 0:50:29It's a place with a rich history and culture.
0:50:38 > 0:50:42Rituals like this are performed all year round to appease the gods
0:50:42 > 0:50:43and ward off misfortune.
0:50:43 > 0:50:45THEY SING
0:50:47 > 0:50:51Yoko and her friend Setsuko are not only hunters,
0:50:51 > 0:50:54they were once Kaminchu, priestesses of high status
0:50:54 > 0:50:57with special privileges to hunt snakes.
0:51:00 > 0:51:04They were made Kaminchu on this same patch of ground in 1978.
0:51:08 > 0:51:11The initiation ceremony was called Izaiho
0:51:11 > 0:51:15and this was the last time it was ever performed.
0:51:17 > 0:51:20As Japan has modernised, many traditions were lost.
0:51:22 > 0:51:24After more than five centuries,
0:51:24 > 0:51:28Yoko and Setsuko are now the last in their line
0:51:28 > 0:51:29who know the old ways.
0:51:33 > 0:51:35Sea snakes have been hunted here for centuries.
0:51:37 > 0:51:39It's another tradition that may soon be lost.
0:52:00 > 0:52:04Despite their age, Yoko and Setsuko are the only ones left
0:52:04 > 0:52:06on the island who still hunt.
0:52:15 > 0:52:18The team has been granted special permission to film them,
0:52:18 > 0:52:22but they have to work in the dark so they don't scare off the snakes.
0:52:24 > 0:52:26(I can see about 20 snakes in here.)
0:52:31 > 0:52:33(She gets right to the back of the cave.)
0:52:34 > 0:52:37For Yoko and Setsuko, this ancient way of hunting
0:52:37 > 0:52:39requires intense concentration.
0:52:46 > 0:52:49The nearest hospital is across the water in Okinawa,
0:52:49 > 0:52:52so if the ladies were bitten they probably wouldn't survive.
0:52:58 > 0:53:01As the snakes swim in on the surge of water,
0:53:01 > 0:53:03the ladies pick them out with their torches.
0:53:13 > 0:53:15But years of experience mean
0:53:15 > 0:53:18they can sense the movement of the snakes in the dark.
0:53:23 > 0:53:25Yoko's poised to strike.
0:53:34 > 0:53:37She's got a massive snake in her hands.
0:53:39 > 0:53:43The team want to get shots of Yoko actually catching the snakes,
0:53:43 > 0:53:46but with such a cramped space to work in
0:53:46 > 0:53:48they need some special technology.
0:53:50 > 0:53:52What does it say?
0:53:52 > 0:53:53It's not saying anything.
0:53:55 > 0:53:59Basically, we're trying to get the camera and my smartphone to
0:53:59 > 0:54:02talk to each other so we can put the camera in the water where the
0:54:02 > 0:54:05sea snakes are, and we can turn it on and off and focus and do all
0:54:05 > 0:54:09the things we need it to do with it, but at the moment it's not working.
0:54:09 > 0:54:11Well, she got another one.
0:54:11 > 0:54:15So while we've got all this ridiculous technological nonsense
0:54:15 > 0:54:18going on, Yoko is just happily plucking the odd snake
0:54:18 > 0:54:20out of the water every five or ten minutes.
0:54:21 > 0:54:27It's working, yay. Look at that. It looks good.
0:54:27 > 0:54:29With the technical problems solved,
0:54:29 > 0:54:31someone has to actually get in the cave.
0:54:33 > 0:54:36David has volunteered, but he'll need some protection.
0:54:36 > 0:54:39Yoko is not wearing any gloves.
0:54:39 > 0:54:40No, Yoko doesn't wear gloves,
0:54:40 > 0:54:43but I'm not putting my hands in water with sea snakes
0:54:43 > 0:54:45crawling everywhere without any gloves on.
0:54:48 > 0:54:50YOKO LAUGHS
0:54:50 > 0:54:52What's so funny?
0:54:52 > 0:54:53Why are you laughing?
0:54:53 > 0:54:55Why are you laughing, Yoko?
0:55:00 > 0:55:02When the night's hunting is over,
0:55:02 > 0:55:06the team discover they only got a few shots of Yoko's legs.
0:55:22 > 0:55:25The next day, the team are invited to Yoko's house.
0:55:25 > 0:55:28She's prepared snake soup for them to eat.
0:55:34 > 0:55:36We're filming...
0:55:36 > 0:55:39snake and now it's time to eat snake.
0:55:41 > 0:55:45I'm resisting the urge to say it tastes like chicken.
0:55:45 > 0:55:47It doesn't taste like chicken.
0:55:47 > 0:55:49It's pretty smoky, isn't it?
0:55:49 > 0:55:50It's a bit snaky.
0:55:56 > 0:55:59For the team, it's an unusual meal, but it's a great honour.
0:55:59 > 0:56:03This dish was once reserved only for the island's kings.
0:56:09 > 0:56:12There is only one night of filming left.
0:56:12 > 0:56:16The team haven't yet got the shots they need of Yoko hunting,
0:56:16 > 0:56:20but they have discovered a second entrance to the cramped cave.
0:56:24 > 0:56:28Unlike the ladies, cameraman Robin is taking all precautions.
0:56:29 > 0:56:30Put the hood on. There you go!
0:56:32 > 0:56:35He's squeezed himself into a tiny
0:56:35 > 0:56:38hole and is now surrounded by venomous sea snakes,
0:56:38 > 0:56:42but he's finally in a position to capture the action.
0:56:57 > 0:57:01OK, she just got a pretty big snake.
0:57:01 > 0:57:04Just saw it just swimming underneath my feet here
0:57:04 > 0:57:08and then it went in a crack in the rock and she came and grabbed it,
0:57:08 > 0:57:10caught it and stuffed it in her bag,
0:57:10 > 0:57:12so I think we've got the shots that we were waiting for
0:57:12 > 0:57:15and I think I can get out of here now, please.
0:57:20 > 0:57:24It's been a successful night for Yoko and Setsuko too.
0:57:27 > 0:57:29- That was astonishing.- Pretty amazing.
0:57:32 > 0:57:34I mean, can you imagine...?
0:57:34 > 0:57:38My mum, most evenings, has a glass of wine or two and watches some telly.
0:57:38 > 0:57:40You can't imagine your mum knee-deep in water,
0:57:40 > 0:57:44writhing with deadly snakes, picking them up and putting them in a bag.
0:58:02 > 0:58:07Next time, we head to Hokkaido - Japan's northern frontier.
0:58:09 > 0:58:12Life is ruled by its extreme seasons.
0:58:15 > 0:58:16Survival means being tough...
0:58:16 > 0:58:18BIRDS SQUAWK
0:58:20 > 0:58:22BIRD SQUAWKS
0:58:22 > 0:58:24..and forging unlikely alliances.
0:58:27 > 0:58:29It's Japan's wildest island.