[MOO] NARRATOR: IN SOME NATURAL WONDERS, WILDLIFE... [HISS] HOLDS THE KEY TO SURVIVAL FOR THE PEOPLE WHO LIVE THERE.

[MAN YELLS] IN THE WETLANDS OF NORTHERN AUSTRALIA, A RANGER RISKS HIS LIFE TO COLLECT SALTWATER CROCODILE EGGS.

ACROSS THE VAST EXPANSE OF SIBERIA, A MAN AND HIS REINDEER... [SPEAKS NATIVE LANGUAGE] MUST MAKE A BRUTAL 500-MILE MIGRATION... [MAN WHISTLING] WHILE IN THE TEA PLANTATIONS OF ASSAM, IT FALLS TO A MAHOUT AND HIS ELEPHANT TO PROTECT A VILLAGE FROM A RAMPAGING HERD.

[MAN SHOUTS IN NATIVE LANGUAGE] IN THESE WONDERS, IT IS ANIMALS THAT MAKE THE DIFFERENCE BETWEEN LIFE AND DEATH.

EARTH'S NATURAL WONDERS ENCOMPASS A HUGE VARIETY OF LANDSCAPES... LUSH TROPICAL FORESTS...

SPECTACULAR ISLANDS...

SOARING MOUNTAIN RANGES... OR FROZEN POLAR WORLDS.

AND FOR THE PEOPLE WHO CALL THESE EXTRAORDINARY PLACES HOME, SURVIVAL REQUIRES SKILL...

INGENUITY... AND BRAVERY.

THIS PROGRAM WAS MADE POSSIBLE IN PART BY CONTRIBUTIONS TO YOUR PBS STATION FROM VIEWERS LIKE YOU.

THANK YOU.

NARRATOR: SIBERIA.

A VAST EMPTY WILDERNESS THAT MAKES UP AROUND 1/12 OF THE EARTH'S ENTIRE LAND SURFACE... AND ONE OF ITS GREAT NATURAL WONDERS IS THE YAMAL PENINSULA, STRETCHING OVER 400 MILES INTO THE ARCTIC CIRCLE.

IT'S KNOWN TO LOCAL NOMADIC PEOPLES AS THE EDGE OF THE WORLD.

THE CLIMATE IS EXTREME.

TEMPERATURES CAN FALL BELOW MINUS 50 DEGREES FAHRENHEIT IN WINTER.

YET THIS HARSH AND UNFORGIVING PLACE IS WHERE THE NENETS PEOPLE HAVE MADE THEIR HOME... AND THEY'D HAVE NO WAY TO SURVIVE HERE WITHOUT REINDEER.

[PEOPLE SPEAKING NATIVE LANGUAGE] NARRATOR: MEDKO SEROTETTO AND HIS FAMILY OWN A HERD OF 5,000 REINDEER.

IT'S SPRING, AND THEY'RE IN THE MIDDLE OF A GRUELING 500-MILE MIGRATION FROM WINTER TO SUMMER PASTURES.

[MEN SHOUTING, DOGS BARKING] IN RECENT YEARS, THE ERRATIC CLIMATE HAS MADE THE MIGRATION HARDER AND HARDER.

MEDKO'S BEEN MAKING THIS JOURNEY FOR OVER 40 YEARS, AND CONDITIONS THIS SEASON ARE AMONG THE WORST HE CAN REMEMBER.

NARRATOR: TO STAY ALIVE, A REINDEER NEEDS TO EAT 3 1/2 POUNDS OF LICHEN, A TYPE OF FUNGI, EVERY DAY.

NARRATOR: ON THE FROZEN SIBERIAN TUNDRA, THE HERD QUICKLY STRIPPED LICHEN PATCHES BARE.

NARRATOR: IT'S NOW 7 WEEKS SINCE THEY LEFT THEIR WINTER PASTURES.

NARRATOR: SO FAR, THEY'VE COVERED 250 MILES, 250 MORE STILL TO GO.

NARRATOR: THEY SHOULD BE COVERING 12 MILES A DAY, BUT THE WEATHER'S DETERIORATING, AND THEY'RE STRUGGLING TO MAKE HEADWAY.

IT'S IMPERATIVE THEY PICK UP THE PACE.

WHILE THE WOMEN AND CHILDREN PACK AWAY THEIR HOMES, THE MEN ROUND UP THE ANIMALS.

[MEN SHOUTING AND WHOOPING] [DOGS BARKING, BELLS CLANGING] IT'S TAKEN SEVERAL HOURS...

BUT THEY'RE FINALLY ON THE MOVE.

THE HERDS TRAVEL IN REINDEER TRAINS UP TO 3 MILES LONG.

IN WORSENING CONDITIONS, IT'S HEAVY GOING.

THE TEMPERATURE'S FALLEN TO MINUS 4 DEGREES FAHRENHEIT WITH WIND CHILL MAKING IT FEEL FAR COLDER.

THEY'VE COVERED LESS THAN 7 MILES, AND ALREADY, THE REINDEER ARE EXHAUSTED.

MEDKO HAS NO OPTION.

HE HAS TO CALL A HALT FOR THE NIGHT AND LET THE HERD REST.

[MAN SPEAKS NATIVE LANGUAGE] NARRATOR: MANY OF THEM ARE PREGNANT AND ARE DUE TO GIVE BIRTH IN JUST A FEW DAYS' TIME.

THERE'S VERY LITTLE LICHEN IN THIS AREA, AND IF THEY DON'T GET TO BETTER FEEDING GROUNDS BY THEN, THEIR CALVES MAY NOT SURVIVE.

NARRATOR: BY MORNING, THE WEATHER'S IMPROVED ENOUGH TO GET MOVING AGAIN...

BUT MEDKO'S FAMILY IS NOT THE ONLY GROUP MAKING THIS JOURNEY.

OTHER HERDS ARE MIGRATING ALONG THE SAME ROUTE.

THE ATROCIOUS WEATHER HAS DELAYED THE OTHERS, AS WELL, AND MEDKO'S ANIMALS SOON CATCH UP WITH A DIFFERENT GROUP.

WITHIN A MATTER OF MINUTES, THE TWO HERDS BECOME ONE.

THEY'RE LOSING VALUABLE TIME.

MEDKO NEEDS TO ROUND THEM UP AS QUICKLY AS HE CAN AND GET MOVING AGAIN.

INCREDIBLY, HE KNOWS EVERY LAST ONE OF HIS ANIMALS BY SIGHT... [MEN SHOUTING] BUT EXTRACTING THEM FROM THE MELEE ISN'T EASY.

ALL OF THE FAMILY HAVE TO HELP, EVEN THE CHILDREN.

AFTER SEVERAL HOURS' HARD WORK, MEDKO FINALLY HAS HIS HERD BACK TOGETHER, BUT IF THE HERD'S TO AVOID STARVATION, THEY MUST COVER MORE GROUND BEFORE NIGHTFALL.

[GRUNTING] [BOY SPEAKING NATIVE LANGUAGE] OVER THE NEXT 7 WEEKS, MEDKO AND HIS REINDEER CONTINUE THEIR BATTLE AGAINST THE ELEMENTS.

BY THE TIME THEY REACH THE SUMMER PASTURES IN EARLY JULY, OVER 1,000 OF THE HERD HAVE BEEN LOST.

NARRATOR: IN SIBERIA, THE NENETS AND THEIR ANIMALS ARE MORE DEPENDENT ON EACH OTHER THAN EVER IN AN INCREASINGLY UNPREDICTABLE WORLD.

IN OTHER NATURAL WONDERS, THE RELATIONSHIP BETWEEN THE PEOPLE AND THE CREATURES THAT LIVE ALONGSIDE THEM IS FAR SIMPLER.

IT'S ONE OF HUNTER AND HUNTED.

AUSTRALIA.

ON ITS FAR NORTHERN COAST IS ARNHEM LAND, A 35,000-SQUARE-MILE AREA OF UNSPOILED WILDERNESS, AND ALONG ITS RUGGED COASTLINE RUNS A REMARKABLE ECOSYSTEM.

THIS NATURAL WONDER IS A MOSAIC OF SWAMPS AND TIDAL SALT MARSHES.

FED BY THE MONSOONS THAT SWEEP IN FROM THE INDIAN OCEAN... [THUNDER] UP TO 20 INCHES OF RAIN CAN FALL IN A SINGLE DAY.

THIS SPRAWLING NETWORK OF CREEKS AND BILLABONGS IS HOME TO ONE OF THE MOST DANGEROUS OF ALL PREDATORS...

THE SALTWATER CROCODILE, THE MOST AGGRESSIVE CROCODILE SPECIES IN THE WORLD.

THEY'RE NOTORIOUSLY SHORT-TEMPERED AND EASILY PROVOKED.

MEASURING UP TO 6 1/2 YARDS IN LENGTH AND WEIGHING AS MUCH AS A TON, IT'S EVERY INCH THE KILLING MACHINE.

BUT FOR THOUSANDS OF YEARS, THE SALTWATER CROC PLAYED A VITAL ROLE IN THE SURVIVAL OF THE ABORIGINAL PEOPLES.

THEY HUNTED CROCS FOR MEAT AND EGGS.

[BIRD SQUAWKING] THE CROCODILE IS IMPORTANT IN SOME ABORIGINAL PEOPLES' SACRED BELIEFS.

IT CAN BE SEEN AS PART SPIRIT FIGURE AND PART ENEMY.

NARRATOR: TODAY, SOME ABORIGINAL PEOPLES STILL USE TRADITIONAL SKILLS TO COLLECT CROC EGGS, RISKING THEIR LIVES IN THE PROCESS.

NARRATOR: GREG WILSON IS A RANGER AND MEMBER OF THE GUN-NARTPA CLAN.

HE AND HIS TEAM ARE PAID TO COLLECT EGGS FOR THE REGION'S COMMERCIAL CROCODILE FARMS... WHERE THE HATCHLINGS ARE REARED FOR THEIR VALUABLE SKINS.

THE RANGERS HAVE AROUND 8 WEEKS TO COLLECT UP TO 2,500 CROC EGGS DURING THE EGG-LAYING SEASON, A QUOTA SET EACH YEAR BY THE NORTHERN TERRITORY GOVERNMENT THERE, THERE!

THERE, THERE, THERE, THERE!

NARRATOR: AS A RESULT OF A BAN ON HUNTING, THE NUMBER OF WILD CROCS HAS SKYROCKETED, AND SO HAS THE NUMBER OF ATTACKS.

JUST 3 WEEKS AGO, A MAN WAS KILLED IN THE AREA.

[MEN SPEAKING ABORIGINAL LANGUAGE] NARRATOR: IT'S MAKING GREG'S JOB MORE DANGEROUS THAN EVER.

TODAY, HE AND HIS TEAM ARE OUT SEARCHING FOR CROCODILE EGGS IN AN AREA WHERE THERE ARE USUALLY PLENTY OF NESTS.

WHOA!

WHOA...

BUT IT'S NOT EASY.

HEAVY RAINS THIS YEAR ARE MAKING THE NESTS HARD TO FIND, AS MANY ARE UNDERWATER.

[THUNDER] NARRATOR: IT'S TOO RISKY TO CONTINUE...

SO THEY HEAD BACK TO BASE.

NEXT MORNING, THE WEATHER'S EASED OFF.

GREG WANTS TO TRY A DIFFERENT AREA, WHERE HE HOPES THERE WILL BE MORE NESTS...

BUT THE ONLY WAY TO GET THERE IS BY HELICOPTER... AND THERE'S AT LEAST ONE AGITATED CROC IN THE SHALLOWS THIS MORNING.

IT'S NOT LONG BEFORE THEY SPOT A LARGE NEST.

ONCE THEY'RE DROPPED IN, GREG AND HIS PARTNER DICKSON ARE ON THEIR OWN.

OHH!

THAT ONE'S BIG!

HEY.

NO, NO, NO.

OOH!

NARRATOR: BEFORE THEY CAN TAKE THE EGGS, THEY HAVE TO DRIVE THE CROC OFF THE NEST.

LEAVE HIM.

GO RIGHT-- GO RIGHT THERE.

[SPEAKING ABORIGINAL LANGUAGE] NARRATOR: IT'S LEFT ITS NEST...

BUT FOR HOW LONG?

NARRATOR: WITH AN ANGRY PREDATOR CLOSE BY, GREG AND DICKSON HAVE TO MOVE FAST, BUT THEY HAVE TO HANDLE THE EGGS WITH CARE.

IF STORED THE WRONG WAY UP, THE EMBRYO WOULD DIE, AND THE EGGS BECOME WORTHLESS.

NARRATOR: IT'S BEEN A GOOD DAY, BUT GREG AND THE TEAM STILL HAVE ANOTHER 4 WEEKS WORKING OUT IN THE CROC-INFESTED WATERS BEFORE THE EGG-COLLECTING SEASON ENDS.

THEY'LL REAR SOME BABY CROCS AT THEIR OWN HATCHERY BEFORE PASSING THEM ON TO THE CROCODILE FARMS AT AROUND 9 MONTHS OLD.

IN THE WETLANDS OF AUSTRALIA'S NORTHERN TERRITORY, GREG WILSON IS SUCCESSFULLY USING TRADITIONAL TECHNIQUES IN A MODERN CONTEXT.

IN OTHER NATURAL WONDERS, DECLINING ANIMAL POPULATIONS ARE MAKING TRADITIONAL WAYS OF LIFE HARDER THAN EVER.

A THOUSAND MILES OFF THE COAST OF EASTERN AUSTRALIA, DEEP IN THE PACIFIC OCEAN LIES THE NATION OF VANUATU... A CHAIN OF VOLCANIC ISLANDS.

THIS SPECTACULAR TROPICAL WONDER BEGAN FORMING AROUND 35 MILLION YEARS AGO.

IN TOTAL, VANUATU HAS OVER 1,500 MILES OF COASTLINE... FRINGED BY STUNNING BEACHES AND CRYSTAL CLEAR WATERS... HOME TO SOME OF THE MOST VIBRANT CORAL REEF SYSTEMS ON THE PLANET... OVER 4,000 SPECIES OF MOLLUSK ALONG WITH SEA SNAKES, EELS, AND A DAZZLING VARIETY OF TROPICAL FISH.

THIS APPEARS TO BE AN UNSPOILED PARADISE FOR EVERYONE WHO LIVES HERE.

[LAUGHTER AND CHATTER] NARRATOR: NIGASAU AND HIS FAMILY LIVE ON FUTUNA, ONE OF VANUATU'S SMALLEST AND MOST REMOTE ISLANDS.

THERE ARE JUST 500 INHABITANTS, AND MUCH OF WHAT THEY EAT COMES FROM THE SEA...

BUT IN RECENT YEARS, THERE'S BEEN A DRAMATIC FALL IN THEIR CATCH.

NARRATOR: INDUSTRIAL FISHING HAS IMPACTED FISH STOCKS ACROSS THIS PART OF THE PACIFIC, AND THE PROBLEM'S BEEN EXACERBATED BY CORAL-EATING SPECIES THREATENING THE REEF.

NIGASAU HAS LONG BEEN THE MAIN PROVIDER OF FISH FOR HIS FAMILY, BUT AT 45, HE NEEDS HELP.

NARRATOR: FUTUNA'S NEXT GENERATION NEED TO STEP UP.

ONLY BOYS LEARN TO FISH ON FUTUNA, AND NIGASAU'S SON MISAKOFI IS READY TO MAKE A START.

SO TODAY, NIGASAU AND MISAKOFI ARE HEADING OUT TO SEA IN SEARCH OF FUTUNA'S MOST PRIZED CATCH...

LOBSTER.

LOBSTER HAVE NEVER BEEN EASY TO FIND, AND NOW IT'S GETTING EVEN HARDER.

ON FUTUNA, THE FISHERMEN FREE DIVE TO COLLECT LOBSTER, AND THE BEST TIME TO DIVE FOR THEM IS AT DUSK WHEN THEY COME OUT TO FEED...

BUT THAT'S NOT THE ONLY CHALLENGE.

JUST AS WITH ITS FISH STOCKS, FUTUNA'S LOBSTER NUMBERS HAVE ALSO DROPPED.

NIGASAU IS HAVING TO HEAD OUT TO DEEPER AND DEEPER WATER TO FIND THEM... AND TODAY, IT'S GOING TO FALL TO MISAKOFI TO DIVE TO THE SEABED TO SEARCH FOR THEM.

IT'S THE ULTIMATE TEST FOR AN ASPIRING FISHERMAN.

MISAKOFI WILL HAVE TO HOLD HIS BREATH AND SWIM DOWN AROUND 30 FEET.

AT THAT DEPTH, THE WATER PRESSURE IS IMMENSE.

YEARS OF LOBSTER FISHING HAVE LEFT NIGASAU WITH PERFORATED EARDRUMS AND BROUGHT HIS DIVING DAYS TO AN END, SO TONIGHT, ALL HE CAN DO IS GUIDE HIS SON FROM THE SURFACE.

TIME TO START SEARCHING.

DIVING THE EQUIVALENT OF A 3-STORY BUILDING QUICKLY PUSHES HIS LUNGS TO THE LIMIT.

HE TRIES A SECOND TIME.

AFTER AN HOUR, MISAKOFI'S BEGINNING TO MASTER THE TECHNIQUE, AND THERE'S PLENTY TO SEE DOWN HERE, BUT SO FAR, NOTHING EDIBLE.

MISAKOFI'S STRUGGLING TO HOLD HIS BREATH LONG ENOUGH TO SEARCH AMONG THE ROCKS... AND HE'S STARTING TO GET TIRED...

BUT HE DOESN'T GIVE UP.

FINALLY AFTER MANY ATTEMPTS... NIGASAU: YES!

NARRATOR: SOON, HE HAS ANOTHER.

IT'S TAKEN MANY HOURS JUST TO FIND TWO LOBSTER.

MISAKOFI'S EXHAUSTED.

NIGASAU DECIDES TO CALL IT A NIGHT AND HEAD BACK TO SHORE...

BUT AT LEAST HIS SON IS STARTING TO ACQUIRE THE SKILLS HE NEEDS TO SURVIVE ON FUTUNA.

[SINGING IN NATIVE LANGUAGE] [SINGING CONTINUES] IT'S ONLY A SMALL CATCH BUT SOMETHING FOR THE TABLE AT LEAST, AND THERE'S ONE NEWLY QUALIFIED FISHERMAN TO CELEBRATE.

[MAN SPEAKING NATIVE LANGUAGE] NARRATOR: FOR THE TIME BEING AT LEAST, THE PEOPLE OF FUTUNA CONTINUE TO SURVIVE THANKS TO THEIR FISHING SKILLS, BUT IN THIS CHANGING NATURAL WONDER, THE FUTURES OF THE NEXT GENERATION ARE LESS CERTAIN.

AS ENVIRONMENTS CHANGE, THE EFFORT TO FIND SUSTENANCE FOR REMOTE PEOPLES IS OFTEN THE MOST IMMEDIATE CHALLENGE, WHETHER DUE TO OVERFISHING IN THE OCEANS OR CHANGING LAND USES DEEP INLAND.

THE FORESTS OF THE CONGO BASIN DEEP IN THE HEART OF CENTRAL AFRICA.

THIS IMMENSE NATURAL JUNGLE COVERS AN AREA OF 700,000 SQUARE MILES.

REFERRED TO AS THE LUNGS OF AFRICA, THIS VAST NATURAL WONDER SPANS 6 COUNTRIES AND CONTAINS AROUND 1/4 OF THE PLANET'S SURVIVING TROPICAL RAIN FOREST.

IT'S SO DENSE THAT EVEN TODAY SOME PARTS REMAIN UNCHARTED TERRITORY.

THE TALLEST TREES REACH UP TO 180 FEET INTO THE SKY.

IN THE THICKEST AREAS, ONLY 1% OF SUNLIGHT REACHES THE GROUND.

THE FOREST IS HOME TO AN INCREDIBLE RANGE OF WILDLIFE... AND FOR AT LEAST 3,000 YEARS, IT HAS ALSO BEEN HOME TO THE MBENDJELE PEOPLE.

[PEOPLE SINGING IN NATIVE LANGUAGE] THE VILLAGE OF MOMBELU... OVER 60 MILES FROM THE NEAREST CITY AND 30 MILES FROM THE NEAREST ROAD.

THE MBENDJELE ARE PRIMARILY HUNTER-GATHERERS.

MOST OF WHAT THEY EAT COMES FROM THE FOREST.

NARRATOR: NIEMU RELIES ON TRADITIONAL HUNTING SKILLS TO CATCH THE WILD ANIMALS FROM THE FOREST THAT FORM A VITAL PART OF THEIR DIET.

HE'S ONE OF THE TOP HUNTERS IN THE VILLAGE...

BUT HE HASN'T BEEN DOING MUCH HUNTING LATELY.

HIS WIFE DIED A FEW MONTHS AGO, LEAVING HIM ALONE WITH THEIR 3 SMALL CHILDREN.

NARRATOR: UNDER MBENDJELE CUSTOM, ALL SORTS OF RESTRICTIONS ARE PLACED ON THE DECEASED'S FAMILY.

NIEMU HAS NOT BEEN ALLOWED TO WASH OR CHANGE HIS CLOTHES FOR OVER 6 MONTHS, AND HE'S NOT BEEN ALLOWED TO LEAD A HUNT...

BUT NOW HIS MOURNING PERIOD HAS ENDED.

NARRATOR: THE HUNT IS ON.

THE VILLAGERS ARE GOING TO USE A GIANT NET.

THEY'RE ONE OF THE LAST GROUPS IN CENTRAL AFRICA TO HUNT THIS WAY.

WOVEN FROM THE BARK OF THE LIANA TREE, THE NETS CAN BE HUNDREDS OF FEET LONG.

BEFORE THEY CAN HUNT, IT MUST BE REPAIRED.

ONCE THE EQUIPMENT'S READY, IT'S TIME FOR THE NEXT STAGE OF PREPARATIONS.

[CLAPPING] [SINGING IN NATIVE LANGUAGE] NARRATOR: BEFORE ANY MAJOR HUNT CAN TAKE PLACE, A SPIRIT OF THE FOREST MUST BE SUMMONED TO AID THE HUNTERS.

[SPEAKING NATIVE LANGUAGE] IT'S DONE THROUGH AN ELABORATE CEREMONY CALLED THE MOKONDI MASSANA.

ONE VILLAGER IS SHROUDED IN LEAVES TO BECOME THE FOREST SPIRIT AND MUST BE BROUGHT TO LIFE BY THE REST OF THE VILLAGE.

THE BETTER THEY SING AND DANCE, THE MORE MEAT THEY'LL CATCH TOMORROW.

NEXT MORNING...

THE ENTIRE VILLAGE SETS OUT FOR THE HUNTING GROUNDS.

[SINGING IN NATIVE LANGUAGE] NIEMU MIGHT BE COORDINATING THE HUNTING PARTY, BUT EVERYONE HAS A PART TO PLAY.

NET HUNTING IS LIKE DRY-LAND TRAWLER FISHING.

WORKING AS A TEAM, THEY STRETCH A NET BETWEEN THE TREES.

[SHOUTS] NARRATOR: THE TRAP IS SET.

[MEN SHOUTING IN NATIVE LANGUAGE] [MEN WHOOPING] THE MEN'S YELPING AND SHOUTING WILL FLUSH OUT ANY ANIMALS HIDING IN THE UNDERGROWTH, DRIVING THEM TOWARDS THE NET.

THE WOMEN WAIT BEHIND THE NET.

[DOGS BARKING] AN ANIMAL BREAKS COVER... [SHOUTING] AND RUNS STRAIGHT INTO THE TRAP.

IT'S ONLY A SMALL PORCUPINE... AND, UNFORTUNATELY, THE FOREST OFFERS UP NOTHING ELSE.

SLENDER PICKINGS LIKE THIS HAVE BECOME ALL TOO FAMILIAR FOR NIEMU IN RECENT YEARS.

THE DEMAND FOR BUSH MEAT IN THE CITIES HAS SEEN THE ARRIVAL OF COMMERCIAL HUNTERS IN THE AREA.

IT'S HAD AN ENORMOUS IMPACT ON THE ANIMAL POPULATION.

THE CENTRAL AFRICAN RAIN FOREST IS ONE OF THE WORLD'S MOST EXTRAORDINARY NATURAL WONDERS BUT ONE WHERE RAPID CHANGE IS AFFECTING BOTH THE ANIMALS AND HUMANS THAT CALL IT HOME.

IN MANY PARTS OF THE WORLD, DEVELOPMENT IS ENCROACHING ON AREAS OF WILDERNESS... AND AS THE DRAMATIC RISE IN HUMAN POPULATION CONTINUES, EXPANSION INTO MANY NATURAL WONDERS IS LEAVING PEOPLE AND ANIMALS COMPETING FOR SPACE.

INDIA.

MARKING ITS NORTHERN BORDER, ONE OF THE MOST FAMOUS NATURAL WONDERS ON EARTH...

THE HIMALAYA.

AMONG THE ICE-CAPPED PEAKS, VAST GLACIERS HAVE FORMED, AND THE MELT WATERS THAT FLOW DOWN FROM THE HEIGHTS FEED A WEB OF FORESTS AND JUNGLES LYING BELOW.

THESE ARE THE TEA PLANTATIONS OF ASSAM... A BEAUTIFUL TAPESTRY OF LUSH GREEN VALLEYS... HOME TO A HUGE DIVERSITY OF ANIMALS... NOT LEAST AMONG THEM THE ASIAN ELEPHANT.

[ELEPHANT GRUNTS] EVERY WINTER, HUNDREDS OF THESE ANIMALS COME DOWN FROM THE MOUNTAIN FORESTS TO THE LOWLANDS OF ASSAM...

BUT OVER THE YEARS, VIRGIN FOREST HAS BEEN CLEARED TO MAKE WAY FOR ASSAM'S RENOWNED TEA PLANTATIONS.

AN ARMY OF TEA PICKERS HAS FOLLOWED, AND MANY OF THEIR HOMES LIE DIRECTLY ON THE ELEPHANTS' ANCIENT MIGRATION ROUTES.

IT'S A RECIPE FOR TROUBLE.

ELEPHANTS ARE DRAWN TO THE VILLAGES IN SEARCH OF FOOD...

IN THE PROCESS, TRAMPLING CROPS AND DAMAGING HOUSES.

ACROSS ASSAM, ELEPHANTS KILL AN AVERAGE OF 65 PEOPLE EVERY YEAR... [ELEPHANTS TRUMPETING] BUT THE VILLAGERS OF ONE REGION HAVE A DEFENSE AGAINST THE MIGRATING HERDS...

THE ELEPHANT EMERGENCY SERVICE, A TEAM OF HIGHLY TRAINED DOMESTICATED ELEPHANTS KNOWN AS KUMKIS AND THEIR RIDERS.

[MAN SPEAKING NATIVE LANGUAGE] BABLU THAPA IS ONE OF THEM.

HE'S A MAHOUT, MEMBER OF THE ANCIENT PROFESSION OF ELEPHANT HANDLERS.

THE BOND BETWEEN A MAHOUT AND HIS KUMKI RUNS DEEP.

[ELEPHANT TRUMPETS] NARRATOR: BABLU IS ABLE TO COMMUNICATE WITH THE KUMKIS BECAUSE THEY UNDERSTAND UP TO 30 COMMANDS.

WHEN TACKLING WILD ELEPHANTS, THEY MUST WORK IN TOTAL HARMONY.

THE MAHOUTS AND THEIR KUMKIS OPERATE ALONGSIDE ASSAM'S FORESTRY DEPARTMENT TO PROTECT 100 VILLAGES SPREAD ACROSS 240 SQUARE MILES.

[MAN SPEAKING NATIVE LANGUAGE] NARRATOR: THEY'RE ON STANDBY TO DEAL WITH WILD ELEPHANT EMERGENCIES 24 HOURS A DAY.

IT'S NOVEMBER, AND THE ELEPHANT MIGRATION SEASON IS AT ITS ABSOLUTE PEAK.

WHEN VILLAGERS SPOT WILD ELEPHANTS APPROACHING THEIR HOMES, THEY CALL HQ.

A PAIR OF KUMKIS ARE IMMEDIATELY DISPATCHED TO PROTECT CONCERNED VILLAGERS.

FOR BABLU AND THE ELEPHANT EMERGENCY SERVICE, IT'S OFTEN A RACE AGAINST TIME.

BABLU AND THE KUMKIS USUALLY GO BY THE MOST DIRECT ROUTE-- ACROSS COUNTRY.

ON THIS TERRAIN, IT CAN TAKE SEVERAL HOURS TO REACH A VILLAGE, AND UNTIL THEY ARRIVE, THE VILLAGERS ARE ON THEIR OWN.

AT SESA, THE VILLAGERS HAVE COUNTED AROUND 30 ELEPHANTS APPROACHING, BUT AS ELEPHANTS ARE A PROTECTED SPECIES, IT'S ILLEGAL FOR THE VILLAGERS TO USE FORCE TO DEFEND THEIR HOMES.

WHEN BABLU AND THE KUMKIS ARRIVE, THEY'LL RELY ON A MORE SUBTLE TECHNIQUE TO DRIVE WILD HERDS AWAY-- ELEPHANT PSYCHOLOGY.

ELEPHANTS LIVE IN TIGHT FAMILY GROUPS, AND AS A RULE, THEY'LL AVOID CONFLICT WITH RIVAL GROUPS.

SO THE MAHOUTS CAN USE THEIR TAME ELEPHANTS TO STEER THE WILD ANIMALS AWAY FROM THE VILLAGES.

THAT'S THE THEORY, BUT FIRST, THEY HAVE TO GET THERE.

[MEN SHOUTING, DRUMMING] IN THE MEANTIME, IT'S UP TO VILLAGERS TO DO WHAT THEY CAN TO KEEP THE WILD HERDS AT BAY.

[SHOUTING AND DRUMMING CONTINUES] [SHOUTING] THEY MAKE AS MUCH NOISE AS POSSIBLE, BANGING DRUMS, SHOUTING AND THROWING FIRECRACKERS TO ATTEMPT TO SCARE THE ELEPHANTS.

THE DANGER IS THIS CAN ENRAGE THE WILD ANIMALS.

[FIRECRACKERS POPPING] [SHOUTING CONTINUES] [FIRECRACKERS POPPING] NARRATOR: AS SOON AS THE EMERGENCY SERVICE ARRIVE AT A VILLAGE, THEY ASSESS THE SITUATION.

USUALLY, THEY'LL LOOK FOR A DOMINANT ANIMAL IN THE WILD HERD.

IF THEY CAN TURN THEM, THE REST OF A HERD WILL FOLLOW, BUT TONIGHT AS BABLU TRIES TO GET INTO POSITION, A GROUP OF YOUNG MALE ELEPHANTS STARTS STAMPEDING.

[MEN SHOUTING] HE NEEDS TO GET RIGHT IN AMONGST THE WILD ANIMALS.

HE RAMS ONE OF THE SMALLER MALES.

IT'S ENOUGH TO MOVE HIM AWAY FROM VILLAGERS AND BACK TOWARD HIS HERD.

BABLU STAYS IN HOT PURSUIT JUST TO MAKE CERTAIN... AND, SURE ENOUGH, THE REST OF THE WILD HERD TURN AND RETREAT.

FOR TONIGHT AT LEAST, THE DANGER HAS PASSED.

BABLU AND THE ELEPHANT EMERGENCY SERVICE HAVE DONE THEIR JOB.

THE INHABITANTS OF SESA VILLAGE CAN SLEEP SAFE, BUT IN THE MORNING COMES A SOBERING DISCOVERY.

ONE OF THE WILD ELEPHANTS GOT TRAPPED IN A DITCH AND DIED DURING THE CHAOS OF THE NIGHT.

DESPITE THE TROUBLE THEY SOMETIMES CAUSE, ELEPHANTS ARE REVERED IN INDIAN CULTURE, AND THE DEATH OF ONE CALLS FOR PRAYER AND A RESPECTFUL BURIAL.

[MEN SPEAKING NATIVE LANGUAGE] IT'S A POIGNANT REMINDER OF THE CONSEQUENCES OF HUMANS AND ANIMALS COMPETING FOR THE SAME LIVING SPACE.

[ELEPHANTS TRUMPETING] CHANGE IS AFFECTING MANY OF EARTH'S NATURAL WONDERS... [NIGASAU SINGING IN NATIVE LANGUAGE] AND PEOPLE ARE INCREASINGLY HAVING TO ADAPT THEIR TRADITIONAL SKILLS IN ORDER TO SURVIVE.

IT'S THIS VERY ADAPTABILITY THAT'S ENABLED HUMAN BEINGS TO ENDURE IN ALL ENVIRONMENTS AROUND THE WORLD, TO SURVIVE IN THE EXTRAORDINARY NATURAL WONDERS THAT SOME CALL HOME.

TO FIND AND FILM ONE OF THE LAST REMAINING EXAMPLES OF NET HUNTING WAS A HUGE CHALLENGE, BUT AS IT TURNED OUT, THE BIGGEST PROBLEM WAS TRANSPORTING 25 BOXES OF FILMING EQUIPMENT TO THE HEART OF THE CENTRAL AFRICAN RAIN FOREST.

THE FIRST PART OF THE JOURNEY WAS RELATIVELY STRAIGHTFORWARD, BUT THEN THEY REACHED THE MOTABA RIVER.

WITH KIT WEIGHING OVER 330 POUNDS, IT WAS OBVIOUS THEY WERE GOING TO NEED MORE THAN ONE BOAT.

SHE LOOKS PRETTY STURDY, ACTUALLY.

QUITE ROBUST.

WE'RE GONNA PILE IT HIGH WITH ALL OUR KIT, AND, UH, THINK IT'S ABOUT 5 HOURS DOWN THE RIVER.

THIS IS WHERE IT GETS REALLY, REALLY INTERESTING.

NARRATOR: IT WAS EARLY AFTERNOON BY THE TIME THE TWO BOATS SET OFF.

SINCE THIS WAS A REMOTE AREA MILES FROM ANY HOSPITAL, THE TEAM HIRED EX-ARMY PARATROOPER AND WILDERNESS MEDIC TOM BODKIN.

BODKIN: JUST WANT TO GET THERE IN GOOD TIME.

WE GOT A WHOLE CAMP TO BUILD BEFORE DARK BASICALLY, SO IT'S NEVER-ENDING, THIS JOURNEY, BUT, HOPEFULLY, WE'LL BE THERE SOON.

I THINK WE'RE THERE.

NARRATOR: 5 DAYS AND SEVERAL THOUSAND MILES FROM HOME, THE CREW AT LEAST HAD FINALLY ARRIVED.

HOME FOR THE NEXT TWO WEEKS, EH?

[INDISTINCT CHATTER] NARRATOR: HOPEFULLY, THE BOAT WITH ALL THE CAMERA KIT WOULDN'T BE FAR BEHIND.

[CHATTER CONTINUES] WITH THE LIGHT FADING RAPIDLY, THEY GOT STUCK INTO BUILDING THEIR CAMP.

ONLY HAS ONE?

NARRATOR: AS DARKNESS FELL, IT BECAME APPARENT THEY HAD A SERIOUS PROBLEM.

YEAH.

WELL, IF WE LEFT AT 2:00, OK, IT'S A 5-HOUR JOURNEY FOR THEM UNDER NORMAL CONDITIONS, RIGHT?

SO THAT BRINGS US UP TO 7:00.

IT'S 2 1/2 HOURS LATE, AND IT'S DARK.

NARRATOR: THEIR SECOND BOAT IS MISSING.

IT WAS CARRYING MOST OF THEIR FILMING EQUIPMENT AND ALL OF THEIR SPARE FUEL, BUT LAUNCHING A SEARCH PARTY IN THE DARK WOULD BE EXTREMELY RISKY.

HOPEFULLY, THEY'RE JUST BROKEN DOWN.

WE'RE RESPONSIBLE FOR EVERYONE'S WELFARE, AND WE CAN'T LEAVE PEOPLE ON THE RIVER UNACCOUNTED FOR, SO, YOU KNOW, I DON'T CARE ABOUT THE CAMERAS AND THE CHARGERS AND THINGS.

IT'S--WE NEED TO FIND OUT THAT EVERYONE'S SAFE AND GET THEM IN.

NARRATOR: SO THEY DECIDED THEY HAD NO OPTION BUT TO RETRACE THEIR ROUTE AND TRY TO FIND THE MISSING BOAT...

BUT IT WASN'T LONG BEFORE THEY QUITE LITERALLY RAN INTO A PROBLEM.

[THUD, BUZZ] THAT MADE A PROPER NOISE.

NARRATOR: THEY'D STRUCK A LOG.

IF THEY'D HOLED THE BOAT OR DAMAGED THE ENGINES, THEY'D BE IN BIG TROUBLE.

FORTUNATELY, EVERYTHING WAS FINE, BUT THEY STILL HAD TO FIND THE MISSING BOAT.

TAKE IT NICE AND GENTLY.

LET'S GET THERE IN THE END.

NARRATOR: HALF AN HOUR LATER, THERE WAS STILL NO SIGN OF IT... AND THEY WERE NOW RUNNING LOW ON FUEL.

JUST WHEN THEY WERE THINKING THEY'D HAVE TO TURN BACK...

IT'S THEM.

YEAH.

[MAN SPEAKING NATIVE LANGUAGE] MAN: THOMAS?

THOMAS?

THOMAS?

AH.

TRÈS BIEN.

LUCKILY, WE'VE JUST FOUND THE OTHER BOAT.

IT'S A HUGE RELIEF, AND THEY'RE ABSOLUTELY FINE.

THERE'S NO PROBLEMS WITH THEM AT ALL.

NARRATOR: THE REASON FOR THE DELAY WAS SOON APPARENT.

[MAN SPEAKING NATIVE LANGUAGE] WE JUST NOTICED THAT THEY'VE CHANGED THE MOTOR, SO THERE'S OBVIOUSLY BEEN AN ISSUE WITH THE ENGINE, AND THEY'VE PICKED UP A NEW ENGINE AT ANOTHER VILLAGE JUST UPSTREAM.

NARRATOR: TOGETHER, BOTH BOATS MADE THEIR WAY BACK UPRIVER TO THE VILLAGE.

PAGLIERO: YEAH.

THIS IS REALLY GOOD NEWS.

THE MAIN THING IS THE GUYS ARE SAFE, SO WE'VE GOT THE FULL TEAM TOGETHER, BUT ALL THE KIT HAS TURNED UP.

WE'VE GOT EVERYTHING WE NEED-- ALL THE CAMERAS, THE CHARGING STUFF, SO WE CAN MAKE A FILM, AND IT MEANS TOMORROW WE CAN JUST GET ON WITH IT.

NARRATOR: THE TEAM WENT ON TO HAVE A FANTASTIC SHOOT WITH THE MBENDJELE, CAPTURING ONE OF THE LAST GROUPS NET HUNTING IN THIS PART OF THE AFRICAN RAIN FOREST.

[VILLAGERS SINGING] STAY TUNED FOR MORE "EARTH'S NATURAL WONDERS" NEXT TIME, IN SOME OF EARTH'S STUNNING NATURAL WONDERS, PEOPLE MUST PUSH THEMSELVES TO THE ABSOLUTE LIMIT IN ORDER TO SURVIVE AGAINST THE ODDS.

DON'T MOVE.

THIS PROGRAM WAS MADE POSSIBLE IN PART BY CONTRIBUTIONS TO YOUR PBS STATION FROM VIEWERS LIKE YOU.

THANK YOU.

"EARTH'S NATURAL WONDERS" LIFE AT THE EXTREMES IS AVAILABLE ON DVD AND BLU-RAY.

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