0:00:05 > 0:00:07There are some places on Earth...
0:00:10 > 0:00:12..that simply take your breath away.
0:00:16 > 0:00:18Lush tropical forests.
0:00:20 > 0:00:22Spectacular islands.
0:00:26 > 0:00:28Soaring mountain ranges.
0:00:31 > 0:00:33Or frozen polar worlds.
0:00:38 > 0:00:42And for the people who call these extraordinary places home...
0:00:43 > 0:00:45..survival requires skill...
0:00:47 > 0:00:48..ingenuity....
0:00:50 > 0:00:52- Look there.- ..and bravery.
0:00:55 > 0:01:01Some natural wonders are simply the most extreme places on the planet
0:01:01 > 0:01:02to live.
0:01:04 > 0:01:07In the greatest mountain range in the world,
0:01:07 > 0:01:11a herder must guide his yaks down a treacherous gorge to get to their
0:01:11 > 0:01:12summer pastures.
0:01:17 > 0:01:22Deep in the Amazon Rainforest an indigenous tribe must learn how
0:01:22 > 0:01:25to save their beautiful home from the threat of fire.
0:01:29 > 0:01:31While in the Arctic,
0:01:31 > 0:01:34a grandmother must slip below the sea ice
0:01:34 > 0:01:36to collect food for her family.
0:01:39 > 0:01:41This is the story of these wonders...
0:01:43 > 0:01:44..and of the people...
0:01:47 > 0:01:48..fighting to survive...
0:01:51 > 0:01:52..and even thrive...
0:01:55 > 0:01:57..in these astonishing places.
0:02:12 > 0:02:17The Himalayas, perhaps the most iconic natural wonder of them all.
0:02:19 > 0:02:22It's the greatest mountain range on earth,
0:02:22 > 0:02:25home to the world's highest peak, Mount Everest.
0:02:31 > 0:02:33Formed around 50 million years ago,
0:02:33 > 0:02:36this is one of the youngest ranges on the planet.
0:02:40 > 0:02:43And it's still growing by around 1cm every year.
0:02:48 > 0:02:52The District of Mustang sits high in the Nepalese Himalayas.
0:02:57 > 0:03:01The thin air and extreme terrain make this a harsh place to live.
0:03:04 > 0:03:08And for the herders who call these mountains home,
0:03:08 > 0:03:11yaks are the key to survival.
0:03:31 > 0:03:3549-year-old Thokmay looks after a herd of 200 yaks.
0:03:38 > 0:03:41He is halfway through the spring migration,
0:03:41 > 0:03:44moving the herd from winter to summer pastures.
0:03:47 > 0:03:50Tomorrow, they face the most dangerous part of the journey...
0:03:53 > 0:03:57..getting the herd down a treacherous 700m near-vertical pass.
0:04:04 > 0:04:08Along with his sister-in-law and a small group of fellow herders,
0:04:08 > 0:04:11Thokmay spends all winter high in the mountains
0:04:11 > 0:04:13in sheltered grazing grounds.
0:04:18 > 0:04:22But now it's spring, and with many of the female yaks pregnant
0:04:22 > 0:04:26and food supplies running low, they need to reach fresh pastures
0:04:26 > 0:04:27as quickly as possible.
0:04:32 > 0:04:37That means a gruelling 27 mile trek down 1,500 metres of some of
0:04:37 > 0:04:40the Himalaya's most extreme mountain terrain.
0:04:46 > 0:04:48They are halfway through this year's migration.
0:05:04 > 0:05:08Everyone is exhausted and supplies are running dangerously low.
0:05:12 > 0:05:14And now there's another problem.
0:05:16 > 0:05:18The unpredictable weather meant the
0:05:18 > 0:05:20yaks mated later than usual this year.
0:05:22 > 0:05:25Now they're calving halfway through the migration.
0:05:31 > 0:05:34Thokmay can hardly remember this ever happening before.
0:05:36 > 0:05:38Now calves, some just a day old,
0:05:38 > 0:05:41are having to brave this gruelling journey.
0:05:46 > 0:05:49And tomorrow, they face the biggest challenge of all...
0:05:53 > 0:05:54..the pass.
0:05:56 > 0:05:59The only alternative is a lengthy detour...
0:06:01 > 0:06:02..that could kill half the herd.
0:06:35 > 0:06:39Tomorrow, Thokmay is putting everything he's got on the line.
0:06:52 > 0:06:53Early morning.
0:06:55 > 0:06:58The herders are preparing for their big descent.
0:07:04 > 0:07:08But before they set off, there's some important business to take care of.
0:07:08 > 0:07:09HE CHANTS
0:07:12 > 0:07:13The puja.
0:07:22 > 0:07:26Thokmay carefully unrolls a prayer flag...
0:07:28 > 0:07:31..and stretches it out across the entrance to the gorge
0:07:31 > 0:07:33they're about to enter.
0:07:42 > 0:07:47By marking the gorge with these flags, and offering up prayers,
0:07:47 > 0:07:51he hopes to be blessed with strength and ultimately a safe passage.
0:07:51 > 0:07:52HE CHANTS
0:08:03 > 0:08:05Prayers over,
0:08:05 > 0:08:07time for a leap of faith.
0:08:13 > 0:08:16The first yaks begin to head down the top of the pass.
0:08:22 > 0:08:24It's narrow and very steep...
0:08:27 > 0:08:30..and the ground is incredibly unstable.
0:08:41 > 0:08:44Some of the yaks are reluctant to make the dissent.
0:08:46 > 0:08:50With a little persuasion, Uttam gets them moving down.
0:09:04 > 0:09:08But now a bank of dense fog is closing in.
0:09:22 > 0:09:27Finally, after two hours, all the yaks are through the most dangerous
0:09:27 > 0:09:28part of the gorge.
0:09:32 > 0:09:35But it's taken its toll on some of the herd.
0:09:38 > 0:09:41One of the calves is badly injured.
0:09:52 > 0:09:56But yaks are so valuable, leaving it to die is unthinkable.
0:10:07 > 0:10:10It will have to be carried for the remainder of the journey.
0:10:13 > 0:10:17And they still have to negotiate their way across several miles
0:10:17 > 0:10:19of rough terrain.
0:10:22 > 0:10:24It takes a further three days...
0:10:26 > 0:10:28..of hard trekking.
0:10:32 > 0:10:35But, finally, home is in sight.
0:11:03 > 0:11:07The long migration is over for this year.
0:11:11 > 0:11:13For Uttam,
0:11:13 > 0:11:17it's an emotional reunion after six months away from her young son.
0:11:25 > 0:11:27While the herd enjoy the summer grazing...
0:11:30 > 0:11:35.. Thokmay enjoys some home comforts with his wife and daughter.
0:12:01 > 0:12:06It might be slow, but change is coming to these mountains.
0:12:10 > 0:12:13Thokmay will have to deal with new challenges
0:12:13 > 0:12:16on these gruelling migrations
0:12:16 > 0:12:19if he and his family are to continue living here.
0:12:24 > 0:12:28But in some natural wonders, it's not new challenges,
0:12:28 > 0:12:31but ancient skills that are helping people to survive.
0:12:38 > 0:12:40The Canadian Arctic.
0:12:41 > 0:12:46An extraordinary natural wonder that makes up almost 40%
0:12:46 > 0:12:48of Canada's entire landmass.
0:12:53 > 0:12:59This coastal landscape is frozen solid for over half the year.
0:13:01 > 0:13:06In winter, temperatures average -20 degrees Celsius.
0:13:13 > 0:13:16But, unbelievably, people live here.
0:13:39 > 0:13:4463-year-old Minnie has lived in the remote village of Kangiqsujuaq
0:13:44 > 0:13:46all her life.
0:13:48 > 0:13:53Survival for this community of 700 still means getting most
0:13:53 > 0:13:54of their food from the land.
0:13:57 > 0:14:01And in winter, Minnie knows exactly where to look for it.
0:14:04 > 0:14:09Tomorrow, she's going to show her granddaughter Eva how to find
0:14:09 > 0:14:13a delicacy that is only available for a few days a year.
0:14:14 > 0:14:15But it's very dangerous.
0:14:32 > 0:14:337am.
0:14:34 > 0:14:37Minnie and her sister Siassie are up early...
0:14:40 > 0:14:42..and heading out onto the sea ice with Eva.
0:14:52 > 0:14:55This is something the women of Kangiqsujuaq
0:14:55 > 0:14:57have done for generations.
0:15:00 > 0:15:03And now, Eva is joining them.
0:15:25 > 0:15:28They are now ten miles out on the frozen sea.
0:15:31 > 0:15:36It might look like there's nothing here, but Minnie knows otherwise.
0:15:42 > 0:15:46It's March, and the spring tides are at their most extreme.
0:15:51 > 0:15:55High and low tides can be up to 60% greater than normal.
0:15:59 > 0:16:02For Minnie, it's the extreme low tide
0:16:02 > 0:16:04that will provide her opportunity.
0:16:06 > 0:16:11As the tide goes out, the frozen sea ice drops by over 15m...
0:16:13 > 0:16:16..and underneath, the sea bed is now fully exposed.
0:16:20 > 0:16:23It's here that Minnie will find her secret larder.
0:16:25 > 0:16:27But it's a race against time.
0:16:29 > 0:16:33The women have just 45 minutes to dig a hole through six feet
0:16:33 > 0:16:35of solid ice...
0:16:38 > 0:16:42..and head under before the tide turns and re-floods the sea bed.
0:16:47 > 0:16:49They're through.
0:16:50 > 0:16:54But with tonnes of constantly shifting ice down there,
0:16:54 > 0:16:57they need to make sure it's safe before they go in.
0:17:11 > 0:17:13They need to look elsewhere.
0:17:15 > 0:17:17But the clock is ticking.
0:17:37 > 0:17:38This one is good.
0:17:41 > 0:17:44But the tide will be back in less than half an hour.
0:17:44 > 0:17:46They need to move fast.
0:18:10 > 0:18:12There are few places on Earth
0:18:12 > 0:18:15where you can walk under the sea like this.
0:18:19 > 0:18:21But this is a perilous place to be.
0:18:30 > 0:18:34The ice above them is no longer supported by sea water...
0:18:37 > 0:18:39..and is extremely unstable.
0:18:41 > 0:18:44The risk of it collapsing at any moment is high.
0:18:46 > 0:18:48But for Minnie, it's worth it.
0:18:50 > 0:18:53She has found the prize she's after.
0:18:56 > 0:18:58Mussels.
0:19:00 > 0:19:01Thousands of them.
0:19:25 > 0:19:28It's a seafood bonanza,
0:19:28 > 0:19:30but Minnie knows how dangerous it is.
0:19:41 > 0:19:44They've been under for 20 minutes,
0:19:44 > 0:19:47and these sea caves will start to re-flood any minute now.
0:20:16 > 0:20:18It's time to go.
0:20:19 > 0:20:22But this is the most dangerous moment for the women.
0:20:24 > 0:20:27As the tide begins to refill these caves with water,
0:20:27 > 0:20:31its movement shifts the huge ice blocks sitting above their heads.
0:20:34 > 0:20:41The risk is that the hole they've entered by closes as the ice moves,
0:20:41 > 0:20:42leaving them trapped underneath.
0:20:57 > 0:20:59They've made it. Just.
0:21:00 > 0:21:03The sea reclaims its secret larder.
0:21:09 > 0:21:12For these mussel gatherers, this dangerous hunt is worth it...
0:21:14 > 0:21:16..and Eva has learned some important skills
0:21:16 > 0:21:18that will last her a lifetime.
0:21:39 > 0:21:44Gathering food like this is a centuries-old tradition
0:21:44 > 0:21:48that provides remote communities like Minnie's with free food.
0:21:53 > 0:21:57But the climate is changing in this natural wonder.
0:22:23 > 0:22:25Change is coming for the Inuit people.
0:22:27 > 0:22:32But, for the time being at least, ancient skills help them to survive.
0:22:36 > 0:22:40But some natural wonders have already changed so much...
0:22:41 > 0:22:46..it's having a devastating impact on the people who live there,
0:22:46 > 0:22:48and the very wonder itself.
0:22:53 > 0:22:55The Amazon basin,
0:22:55 > 0:22:59home to the largest rainforest on Earth.
0:23:08 > 0:23:11Over 380 billion trees...
0:23:12 > 0:23:17..covering around a third of South America's entire landmass.
0:23:20 > 0:23:23A unique natural wonder,
0:23:23 > 0:23:28home to a dizzying array of plants, animals, and insects.
0:23:30 > 0:23:33And where new species are still being discovered.
0:23:35 > 0:23:40But now, large areas of this rainforest are being destroyed...
0:23:42 > 0:23:43..by fire.
0:23:46 > 0:23:50It is the height of the fire season and hundreds are burning
0:23:50 > 0:23:51across the Amazon.
0:24:21 > 0:24:26Edimar Dos Santos Abreu is the chief of the Alianca fire brigade.
0:24:30 > 0:24:34He and a team of just eight firefighters are responsible
0:24:34 > 0:24:39for protecting a part of Brazil's Mato Grosso region.
0:24:39 > 0:24:42It's a huge area, the size of England and Wales.
0:25:01 > 0:25:05Most the of fires they deal with are set by farmers clearing land.
0:25:07 > 0:25:10These fires often rage out of control.
0:25:16 > 0:25:19The fires are now endangering the Xingu National Park.
0:25:22 > 0:25:25Much of this region is made up of virgin rainforest.
0:25:31 > 0:25:35Today, Edimar and his team are flying into the Xingu.
0:25:38 > 0:25:42They're working with a tribe whose very existence is now threatened
0:25:42 > 0:25:44by the fires.
0:25:51 > 0:25:55The Kamaiura are one of 14 indigenous groups who live here.
0:25:59 > 0:26:02They rely on the forest for everything...
0:26:04 > 0:26:08..from the material they use to build their houses
0:26:08 > 0:26:09to the food they eat.
0:26:11 > 0:26:14But now the fires are putting their livelihood at risk...
0:26:17 > 0:26:19..and they don't know how to control them.
0:26:24 > 0:26:26As Edimar flies over the area,
0:26:26 > 0:26:29the sheer scale of the problem is all too clear.
0:26:33 > 0:26:36Deforestation has become so widespread,
0:26:36 > 0:26:38it's upset the delicate microclimate.
0:26:41 > 0:26:44Without the dense canopy of trees,
0:26:44 > 0:26:47humidity across the region has dropped dramatically
0:26:47 > 0:26:49and the ground is now tinderbox dry.
0:26:53 > 0:26:56The Kamaiura have always used fire
0:26:56 > 0:27:00to clear small patches of forest for their crops.
0:27:00 > 0:27:02But now, they spiral out of control.
0:27:07 > 0:27:09Edimar has come to help them.
0:28:01 > 0:28:06Edimar and his team are training the Kamaiura to be firefighters.
0:28:08 > 0:28:12And it's not long before they are all called into action.
0:28:15 > 0:28:19A fire is sweeping through the forest just a few miles away.
0:28:27 > 0:28:31If the wind changes direction, it could threaten the village.
0:28:35 > 0:28:39With the ground this dry, the fire will spread rapidly.
0:29:02 > 0:29:06They create a fire break, clearing a line of land of any
0:29:06 > 0:29:07combustible material.
0:29:10 > 0:29:12This barrier is a simple,
0:29:12 > 0:29:16but effective way of stopping a fire in its tracks.
0:29:21 > 0:29:23It takes several hours...
0:29:27 > 0:29:31..but they eventually manage to get the blaze under control.
0:29:37 > 0:29:40The Kamaiura need to pick up these important firefighting
0:29:40 > 0:29:42skills, and quickly.
0:29:46 > 0:29:49Mato Grosso's fires are getting steadily worse
0:29:49 > 0:29:50with each passing year.
0:29:53 > 0:29:55And as Edimar leaves the Kamaiura,
0:29:55 > 0:29:59a call comes in that another fire has taken hold,
0:29:59 > 0:30:00200 miles away...
0:30:03 > 0:30:04..and it's massive.
0:30:06 > 0:30:10Ten square miles of rainforest is ablaze.
0:30:16 > 0:30:20By the time Edimar and his team are on site,
0:30:20 > 0:30:22it's been burning for 12 hours.
0:30:27 > 0:30:32The sheer scale of the task facing this small team is daunting.
0:31:01 > 0:31:04They can't hope to put a fire this big out,
0:31:04 > 0:31:07but they might be able to stop it from spreading any further.
0:31:09 > 0:31:14They must create a fire break, only this time on a much bigger scale.
0:31:29 > 0:31:33By daybreak, one section of the fire is finally under control.
0:31:37 > 0:31:40The team have managed to stop it spreading any further.
0:31:45 > 0:31:48They have now been working for 14 hours straight.
0:31:50 > 0:31:55But during the height of the fire season, this is a normal shift.
0:32:24 > 0:32:28The rate of change in the forests of the Amazon is sobering...
0:32:30 > 0:32:34..and traditional communities will have to learn new skills if they are
0:32:34 > 0:32:36to continue to live here.
0:32:39 > 0:32:43In one natural wonder, people have done just that...
0:32:45 > 0:32:49..by using technology and learning new skills to survive
0:32:49 > 0:32:53in an area that once supported little life.
0:32:57 > 0:33:01Australia, and in Queensland,
0:33:01 > 0:33:04a natural wonder five times the size of Britain.
0:33:08 > 0:33:14Part of the outback, a huge, unbroken expanse of wilderness.
0:33:16 > 0:33:19One of the planet's great semiarid landscapes.
0:33:22 > 0:33:26Scorched by temperatures in excess of 40 degrees Celsius.
0:33:29 > 0:33:33Only the hardiest species can survive in this searing heat.
0:33:39 > 0:33:42But, in recent years, thanks to technology,
0:33:42 > 0:33:46a new use has been found for this harsh landscape.
0:33:48 > 0:33:50Supersized cattle farms.
0:33:54 > 0:33:57Around 10 million beef cattle roam the outback here.
0:34:00 > 0:34:03But to survive in this hostile terrain,
0:34:03 > 0:34:06the cattle need a huge area to graze across.
0:34:08 > 0:34:13Vegetation is sparse and they must cover enormous distances
0:34:13 > 0:34:14in search of food and water.
0:34:17 > 0:34:19As a result, the cattle farms are vast.
0:34:21 > 0:34:26Rounding up all the animals for market is a massive task,
0:34:26 > 0:34:29and it takes a very special kind of cowboy.
0:34:34 > 0:34:36One that can fly a helicopter.
0:34:38 > 0:34:39But it's dangerous work.
0:34:42 > 0:34:46A lot of unfortunate accidents happen where the pilots
0:34:46 > 0:34:48don't go home to their families,
0:34:48 > 0:34:51and, yeah, we do see a lot of them every season.
0:34:55 > 0:35:0024-year-old Chris is an outback rancher born and bred.
0:35:05 > 0:35:09He has worked as a cowboy since he was 15 years old.
0:35:11 > 0:35:16I've always loved the bush and just the way of life that's out here.
0:35:16 > 0:35:19Still the last frontier in some areas that isn't so developed
0:35:19 > 0:35:23and your job's not your nine to five, it's your life.
0:35:25 > 0:35:28But last year, Chris switched from horses...
0:35:29 > 0:35:30..to a helicopter.
0:35:32 > 0:35:35And today he's facing his biggest test yet...
0:35:37 > 0:35:40..rounding up over 300 head of cattle
0:35:40 > 0:35:44and driving them across the bush to their holding pens ready for market.
0:35:46 > 0:35:50As a rookie, he's mentored by senior heli-musterer Les Payne.
0:35:50 > 0:35:53When we get out there, just follow me around for a while,
0:35:53 > 0:35:55and I'll show you from the air the areas we're going to work.
0:35:55 > 0:35:57Yeah, no worries. Sounds good.
0:35:59 > 0:36:04But in the heli-mustering business, there's little room for error.
0:36:04 > 0:36:06- Good to go?- Yeah, go on.
0:36:12 > 0:36:15I think it's dangerous in a lot of ways.
0:36:15 > 0:36:19You know, if someone makes a mistake, it comes up pretty quickly.
0:36:19 > 0:36:21There's not much margin for error.
0:36:23 > 0:36:25Do you see where we've got to go up there?
0:36:25 > 0:36:26Yeah, I think I see the dust.
0:36:28 > 0:36:30The first challenge is finding the cattle.
0:36:34 > 0:36:38I've got a view up on this range here.
0:36:38 > 0:36:39Good to go.
0:36:39 > 0:36:42Chris needs to drive the cattle out from under the trees
0:36:42 > 0:36:45and into the open,
0:36:45 > 0:36:49so he performs a manoeuvre most pilots would never normally attempt...
0:36:51 > 0:36:56..dropping from 600m to around 10m in a matter of seconds.
0:37:00 > 0:37:05He's aiming to spook the cattle and flush them out from among the trees.
0:37:07 > 0:37:10- How you doing, mate? - Yeah, going all right.
0:37:10 > 0:37:12By flying this low and slow,
0:37:12 > 0:37:17heli-musterers put themselves in what they call the dead man's curve.
0:37:17 > 0:37:19It's a risky place to be.
0:37:19 > 0:37:23Being at that height, you've got a lot less time to react to obstacles.
0:37:23 > 0:37:25If something goes wrong, you could be on the ground in just
0:37:25 > 0:37:27a matter of seconds.
0:37:34 > 0:37:35Within a couple of hours,
0:37:35 > 0:37:38they've forced a big herd into the open bush.
0:37:42 > 0:37:43But the day is wearing on.
0:37:45 > 0:37:47There's still five miles to cover
0:37:47 > 0:37:50if they're to reach the holding pen before nightfall.
0:37:54 > 0:37:57They are now joined by a ground support team.
0:37:59 > 0:38:02But as a key part of the muster, Chris and Les must make sure
0:38:02 > 0:38:05the herd are held together and guided home.
0:38:08 > 0:38:10You've got to be a good stop man and understand what's happening.
0:38:10 > 0:38:14The cattle, the landscape - you've got to be able to read that.
0:38:16 > 0:38:18They are making good progress,
0:38:18 > 0:38:23but standing between them and the holding pen is a final obstacle,
0:38:23 > 0:38:26one feared by every heli-musterer.
0:38:27 > 0:38:28Water.
0:38:30 > 0:38:34- Do you see where we got to go up there?- Yeah, I think I see that water.
0:38:34 > 0:38:36Water is a real hazard.
0:38:39 > 0:38:43At this height, spray is whipped up by the rotary blades
0:38:43 > 0:38:46and could easily be sucked into the fuel intake.
0:38:49 > 0:38:51That would bring Chris's helicopter down instantly.
0:38:56 > 0:38:59When you're above water, and the fact that the water is moving,
0:38:59 > 0:39:01it can disorient pilots.
0:39:01 > 0:39:05And unfortunately, some people can end up diving into the water or
0:39:05 > 0:39:06striking a bit of the water.
0:39:08 > 0:39:11- All good?- Yeah, no worries here.
0:39:11 > 0:39:15Chris needs to stay this low to keep the herd moving.
0:39:19 > 0:39:21But it's working.
0:39:23 > 0:39:25Bit slow to get going with all that water spreading,
0:39:25 > 0:39:27they're all over the show.
0:39:30 > 0:39:33Finally, they get all the herd safely across the water.
0:39:38 > 0:39:45After hours of flying in gruelling 40 degree heat,
0:39:45 > 0:39:48Chris and Les have made it to the holding pens.
0:39:58 > 0:40:04With heli-muster pilots dying every season in the Australian outback,
0:40:04 > 0:40:08Chris knows that he's chosen a very dangerous way to make a living.
0:40:10 > 0:40:15But, in a landscape this big, it's simply the only way to farm.
0:40:17 > 0:40:20The risks do stack up against you. It makes it quite dangerous.
0:40:22 > 0:40:25You can be quite vulnerable at times,
0:40:25 > 0:40:30but, at the end of the day, a 500 cow is not worth a 250,000 machine.
0:40:37 > 0:40:41Whether or not you have modern technology at your fingertips,
0:40:41 > 0:40:45surviving in some of Earth's natural wonders means adapting
0:40:45 > 0:40:47to rapidly changing environments.
0:40:51 > 0:40:56And that includes spotting a new opportunity in one of the most
0:40:56 > 0:40:58unlikely places.
0:41:02 > 0:41:05The Siberian tundra,
0:41:05 > 0:41:11a natural wonder shaped by the winds and glaciers of the last Ice Age.
0:41:11 > 0:41:16It stretches over a million square miles across northern Russia.
0:41:22 > 0:41:26And Yakutia, in the eastern corner of this region,
0:41:26 > 0:41:29is one of its most remote parts.
0:41:32 > 0:41:36In winter, it's a permanently frozen wilderness...
0:41:38 > 0:41:42..blasted by Arctic winds where almost nothing survives.
0:41:45 > 0:41:49But, in summer, this landscape is completely transformed.
0:41:55 > 0:42:00The frozen tundra becomes a vast, colourful heathland...
0:42:09 > 0:42:12..and the landscape is peppered with a magnificent tapestry
0:42:12 > 0:42:14of lakes and pools.
0:42:22 > 0:42:25Anton lives in Moscow...
0:42:27 > 0:42:30..but he was born and raised in this wilderness.
0:42:46 > 0:42:50Every summer, he returns and reunites with old friends...
0:42:52 > 0:42:54..to search for buried treasure.
0:42:57 > 0:42:58Mammoth tusks.
0:43:03 > 0:43:06But finding them is like looking for a needle in a haystack.
0:43:24 > 0:43:27Anton and the team have been here for a week,
0:43:27 > 0:43:30living almost entirely off the land.
0:43:35 > 0:43:38They've been scouring vast areas of this tundra
0:43:38 > 0:43:40looking for mammoth tusks.
0:43:42 > 0:43:44But the season is now coming to an end
0:43:44 > 0:43:47as the Siberian winter approaches.
0:43:50 > 0:43:54The key to their search is a layer of frozen subsoil
0:43:54 > 0:43:56known as permafrost.
0:43:58 > 0:44:01Stretching up to 1,500 metres down,
0:44:01 > 0:44:04it has existed for thousands of years.
0:44:07 > 0:44:09But, in recent times,
0:44:09 > 0:44:13rising temperatures have meant that more and more of it is thawing
0:44:13 > 0:44:14in the summer months.
0:44:18 > 0:44:22And the remains of mammoths that have been buried deep
0:44:22 > 0:44:27in the permafrost for thousands of years are now being exposed,
0:44:27 > 0:44:28including their tusks.
0:44:41 > 0:44:44With the sale of ivory banned across much of the world,
0:44:44 > 0:44:48mammoth-tusk hunting is controversial.
0:44:48 > 0:44:51Many believe it encourages the global trade in ivory.
0:44:57 > 0:45:01But the reality is, Anton's search is legal.
0:45:02 > 0:45:05There's a lot of ivory out there...
0:45:05 > 0:45:06..somewhere.
0:45:18 > 0:45:19Early morning...
0:45:22 > 0:45:24..and after a quick breakfast,
0:45:24 > 0:45:27the mammoth hunters begin their search.
0:45:32 > 0:45:35They start by looking along the banks of the river,
0:45:35 > 0:45:37beneath the permafrost layers.
0:45:48 > 0:45:53Anton hopes that the melting permafrost may have exposed tusks
0:45:53 > 0:45:56or caused them to collapse into the bank.
0:46:00 > 0:46:04Before long, one of the team spots something on the river bank.
0:46:11 > 0:46:13The team carefully excavate the area.
0:46:22 > 0:46:25It's a mammoth tusk, and a decent-sized one.
0:46:28 > 0:46:29But it's not in good condition.
0:46:32 > 0:46:35Mammoth tusks come in three grades,
0:46:35 > 0:46:38determined by how well-preserved the ivory is.
0:46:39 > 0:46:42This is grade three, the lowest quality.
0:46:44 > 0:46:46It's still worth around 2,000...
0:46:48 > 0:46:50..but to make this trip worthwhile,
0:46:50 > 0:46:54Anton needs to collect at least 30 times this amount.
0:46:55 > 0:46:58And as mammoth remains are often found in groups,
0:46:58 > 0:47:01he's confident they'll find more here.
0:47:03 > 0:47:06He decides to adopt a different approach.
0:47:08 > 0:47:09Diving.
0:47:11 > 0:47:14He wants to check in the deeper parts of the river.
0:47:16 > 0:47:18As the river banks erode,
0:47:18 > 0:47:22Anton knows that tusks are sometimes exposed and fall into the water.
0:47:39 > 0:47:44Diving in fast-flowing water chilled by freezing blocks of permafrost
0:47:44 > 0:47:46is tough work.
0:48:01 > 0:48:05Anton tries to sort through the silt, feeling for a tusk.
0:48:05 > 0:48:10But, with almost zero visibility, conditions today are terrible.
0:48:13 > 0:48:17After three hours in the freezing water, and nothing to show for it,
0:48:17 > 0:48:19they call off the search.
0:48:26 > 0:48:28Back to plan A.
0:48:42 > 0:48:46Just downstream, they spot something poking out of the water.
0:48:57 > 0:49:01This time, it looks like it has freshly fallen from the permafrost.
0:49:06 > 0:49:09The quality looks excellent.
0:49:27 > 0:49:31It's not as big as the tusk they found previously,
0:49:31 > 0:49:34but if it's confirmed to be grade one,
0:49:34 > 0:49:36it'll be worth around 5,000.
0:49:42 > 0:49:46They need to find far more like this to make the trip worthwhile.
0:49:50 > 0:49:53Much of this ivory is carved and sold in China.
0:49:56 > 0:49:59But although the Chinese have recently banned the sale of elephant ivory...
0:50:01 > 0:50:04..the trade in mammoth ivory remains legal.
0:50:12 > 0:50:18Life in many of Earth's natural wonders is changing faster
0:50:18 > 0:50:20than ever before.
0:50:20 > 0:50:23And in order to survive, people are having to adapt.
0:50:26 > 0:50:29For some, it means developing new skills
0:50:29 > 0:50:31to deal with very new problems.
0:50:33 > 0:50:38While for others it means passing on ancient skills
0:50:38 > 0:50:40to put food on the table.
0:50:44 > 0:50:48But as these natural wonders continue to change,
0:50:48 > 0:50:54there is little doubt that people will need as much ingenuity, skill,
0:50:54 > 0:50:56and courage as ever
0:50:56 > 0:51:04if they are to go on living in these extraordinary places they call home.
0:51:20 > 0:51:24The team who headed out to the Canadian Arctic to capture the lives
0:51:24 > 0:51:29of the Inuit mussel hunters, knew they would face a lot of challenges.
0:51:35 > 0:51:38The trip was planned to coincide with the spring tides
0:51:38 > 0:51:40that are the key to the hunt.
0:51:43 > 0:51:45They would be at their most extreme in a few days' time.
0:51:48 > 0:51:52But the first challenge the team faced was adapting to Arctic
0:51:52 > 0:51:53winter conditions.
0:51:57 > 0:52:00Just moving around is an issue here.
0:52:04 > 0:52:05I'm still in one piece!
0:52:09 > 0:52:11HE CHUCKLES
0:52:12 > 0:52:14LAUGHTER
0:52:15 > 0:52:19The weather is unpredictable and progress is painfully slow.
0:52:21 > 0:52:23Visibility is pretty, pretty poor today.
0:52:23 > 0:52:26I want to try and get a reveal shot of the town.
0:52:30 > 0:52:32The team are here for just a few days.
0:52:33 > 0:52:36If conditions remain this bad, they'll have no chance of getting
0:52:36 > 0:52:39out on the sea ice to film the sequence they've come to capture.
0:52:42 > 0:52:45I can't really see any definition at the moment.
0:52:45 > 0:52:48This is a white frame.
0:52:48 > 0:52:50They need to hope for better weather tomorrow.
0:52:55 > 0:52:56Mussel harvest day...
0:52:56 > 0:52:59Oh, we can go though, it's fine. You guys can go.
0:52:59 > 0:53:01..and the weather is perfect.
0:53:02 > 0:53:06The crew follow the women out into the bay, ahead of low tide.
0:53:10 > 0:53:13It'll be at its lowest in just two hours.
0:53:14 > 0:53:18The team must first find a safe spot to head under the ice.
0:53:22 > 0:53:24Whilst the women dig their hole,
0:53:24 > 0:53:27the crew need a parallel one so they can capture all the action
0:53:27 > 0:53:29from below.
0:53:33 > 0:53:35I hope it's strong.
0:53:35 > 0:53:38Despite the fixer's reassuring words,
0:53:38 > 0:53:41it's very unstable under the ice pack,
0:53:41 > 0:53:45and only two of the crew can go under.
0:53:45 > 0:53:48The series director and cameraman will be on their own.
0:53:52 > 0:53:54The tide is now fully out...
0:53:55 > 0:53:57..and the clock is ticking.
0:54:03 > 0:54:09We've just headed under for about half an hour, 45 minutes maybe,
0:54:09 > 0:54:11to shoot the sequence that we need.
0:54:12 > 0:54:16It's very cramped in here, everybody is kind of stooping down,
0:54:16 > 0:54:18it's not unlike potholing.
0:54:19 > 0:54:22They have a very short window to get all the action
0:54:22 > 0:54:24before the tide returns.
0:54:25 > 0:54:28But as soon as they're in, Will has a problem.
0:54:28 > 0:54:31Just got in, what we're trying to do is to acclimatise the camera.
0:54:31 > 0:54:34So we've been wrapping the cameras in heat warmers so they
0:54:34 > 0:54:38don't steam up, cos outside is -20, in here's four.
0:54:38 > 0:54:41We've got big condensation problems, so we're trying to find a position
0:54:41 > 0:54:45- where we're not dripping, so we've got a nice dry bit here.- 23 minutes.
0:54:49 > 0:54:51They need to start filming.
0:54:51 > 0:54:52I'm coming in here.
0:55:00 > 0:55:02As the women start collecting mussels...
0:55:04 > 0:55:06..the cramped and slippery conditions
0:55:06 > 0:55:08make it hard for everyone.
0:55:09 > 0:55:12- Whoa, you all right? You OK? - Yes.
0:55:14 > 0:55:17How much time do they think we have?
0:55:17 > 0:55:19I'm slightly worried about the time.
0:55:25 > 0:55:29The women head deeper into the caves and Will has to follow them.
0:55:34 > 0:55:36Switch lenses, Will!
0:55:36 > 0:55:40Russell has to shout his directions to him, which creates a problem.
0:55:41 > 0:55:44I have signal again, I'm rolling.
0:55:44 > 0:55:46Minnie was telling me off there for shouting because,
0:55:46 > 0:55:50when you shout, it reverberates against the ice wall and makes
0:55:50 > 0:55:52the ice pack quite unstable.
0:55:52 > 0:55:55Which is obviously bad news, so lesson learned.
0:55:58 > 0:56:01With the water coming in fast, it's time to leave.
0:56:05 > 0:56:07Come on, Will, let's go.
0:56:08 > 0:56:11OK, guys, for safety we're going to come out here. Can you help me out?
0:56:18 > 0:56:20Whoo!
0:56:22 > 0:56:23Will is the last one out.
0:56:24 > 0:56:26That was absolutely mental.
0:56:28 > 0:56:34It's flat-out crawling in water with the ice against your head.
0:56:34 > 0:56:37Eva took me down some mad narrow chambers.
0:56:37 > 0:56:39She is one brave woman.
0:56:39 > 0:56:41Absolutely amazing.
0:56:41 > 0:56:45Everybody is soaking wet, so the plan now is to leg it home
0:56:45 > 0:56:48and get some... Get some dry clothes
0:56:48 > 0:56:50and some hot tea inside us.
0:56:50 > 0:56:51What a great session.
0:56:53 > 0:56:55It's been tough work,
0:56:55 > 0:56:58but the Earth's Natural Wonders team have managed to capture
0:56:58 > 0:57:00a food-harvesting tradition...
0:57:01 > 0:57:05..that is practised in few other places on the planet.
0:57:08 > 0:57:10Next time...
0:57:11 > 0:57:13In many natural wonders...
0:57:14 > 0:57:17..it's animals that can make the difference between life...
0:57:19 > 0:57:20..and death,
0:57:20 > 0:57:24as people struggle to survive in some of the planet's
0:57:24 > 0:57:27most extraordinary places.