[ Whale surfaces ] Narrator: The tip of Patagonia stretches into the great Southern Ocean, where giants roam.

[ Whale trills, squeaks ] In the deep, all is quiet.

But above, a storm is raging.

[ Monje speaking Spanish ] Narrator: At these latitudes, the sea can be terrifying.

They say that below 40 degrees south, there is no law, but below 50, there is no god.

♪ ♪ At the ends of the Earth is a land of extremes... ...home to spectacular wildlife.

For centuries, people and animals have battled for supremacy.

But now, enemies are becoming allies.

Together they face new challenges... ...in a rapidly changing world.

You are at the mercy of the elements.

Narrator: This is the story of what it takes to survive... ...on the edge of the world.

♪ ♪ Patagonia's far south is dominated by the wind... [ Wind whistling ] ...and the cold.

♪ Extending below the 50th parallel, no other land mass lies so close to Antarctica.

♪ To survive here takes resilience... [ Birds squawking ] ...determination, and sometimes sheer size.

♪ Much of the land is just empty, wind-blasted tundra.

But the sea is teeming with life.

♪ A humpback whale.

[ Whale calls ] This 30-ton giant has traveled all the way from its winter breeding grounds in the tropical Pacific, a journey of more than 4,000 miles.

On its tail is wildlife veterinarian Frederick Toro.

[ Toro speaking Spanish ] Narrator: These are the waters of the Francisco Coloane Marine Park in the Straits of Magellan.

In 1997, marine biologists realized this is an important feeding ground for humpbacks.

[ Birds squawking ] The forceful mixing of the Atlantic and Pacific oceans stirs up nutrients, creating plankton blooms, the foundation of the marine food chain.

Food is so plentiful, the whales behave in extraordinary ways.

[ Toro speaking Spanish ] ♪ Wow.

Narrator: But the whales aren't the only ones plying these waters.

[ Foghorn blows ] The steady stream of ships through the Straits might drive away the whales entirely.

♪ [ Foghorn blows ] To make his case, Frederick needs proof that the whales are stressed -- and that means taking a sample.

♪ But chasing whales in boats may panic them.

♪ So Frederick and his team are trying something new.

A drone.

Its mission?

To hover over the whale's spout and catch a sample of its snot.

[ Drone whirring ] ♪ Spout samples reveal levels of stress hormones as well as pollution.

But catching a sample is easier said than done.

The timing has to be just right.

♪ ♪ Missed.

The whale disappears.

♪ Flying against the wind, the drone's battery is running out of juice.

[ Drone whirring, beeping ] If the whale doesn't surface soon, they'll have to give up.

♪ ♪ One last chance.

♪ Got it.

♪ ♪ [ Toro speaking Spanish ] Frederick hopes that his sample will provide the proof that these humpbacks need protection.

The rich waters of Patagonia's far south have the power of life... ...and death.

♪ [ Boat engine whirring ] Narrator: Crab fisherman Fernando Monje has worked the waters of the Beagle Channel for over a decade.

♪ The 130-mile seaway runs east-west across Patagonia.

The narrow channel funnels the Southern Ocean's ferocious winds.

♪ [ Monje speaking Spanish ] [ Birds squawking ] Narrator: Some ships don't make it.

The waters of the far south have claimed well over 1,000 ships... ...and more than 10,000 sailors.

♪ At first, Fernando saw these wrecks as nothing more than rusting monuments.

But then he decided to take a closer look.

♪ [ Monje speaking Spanish ] Narrator: Nature has claimed this steel hulk.

Thanks to the nutrients stirred up by the storms, these waters are full of life.

♪ But free-diving here is risky.

You can easily get disoriented... ...even trapped.

Luckily, today's conditions are good.

Fernando gets out safely with his haul.

He makes a good living from the shellfish he collects here.

♪ ♪ ♪ Further up the coast, another underwater forager is also returning home.

♪ [ Penguins honking ] ♪ A mother gentoo penguin bringing food to her baby.

She's back on Hammer Island after a 10-hour fishing trip.

♪ She swam nearly 13 miles, diving down 200 feet or more to feed.

Now she hikes through hoards of her cousins -- Magellanic penguins.

♪ ♪ [ Penguins trilling, honking ] Exhausted, but home at last.

Finally, a chance to rest.

Or maybe not.

Her 6-week-old chick is ravenous.

[ Chick chirping ] Growing fast, he has an insatiable appetite.

Mom needs to keep some food back for herself, but her chick won't take "no" for an answer.

♪ ♪ Sometimes it's not easy being a mom.

♪ And raising a family here is especially hard.

One moment, you're basking in the sunshine.

The next, you're being stalked by an outsider.

[ Penguin squeaking ] ♪ Narrator: On Hammer Island, deep in the far south, gentoo penguins face a harsh and remote existence.

But they're not alone.

♪ This is marine biologist Dr. Andrea Raya Rey.

[ Rey speaking Spanish ] [ Clicking tongue ] Narrator: Andrea and her team don't just observe the penguins.

They get hands-on.

[ Dramatic music plays ] ♪ [ Penguins chirping ] They take blood samples and give the birds a health check.

Narrator: Studying them on land is one thing.

But what happens when the gentoos go to sea?

Andrea wants to learn how they feed.

A small camera is attached to this male's back to document his hunting strategy.

♪ Ungainly on land, the gentoo is the world's fastest underwater bird.

♪ His wings propel him at over 20 miles per hour into a shoal of small fish.

♪ But he's not the only one feasting here.

Seabirds dive in from above, grabbing what they can.

Gentoos were thought to primarily feed at depth, but now Andrea has discovered that they're also opportunistic feeders.

♪ Right now, there are only 50 pairs of gentoos living on Hammer Island.

But the colony is growing.

Fish are plentiful in the open water, and nearby is a habitat that supports yet more food.

[ Penguins honking ] ♪ A giant kelp forest.

♪ ♪ Like an underwater rainforest, it's one of the most biodiverse habitats in the ocean, providing food and shelter for hundreds of species.

♪ ♪ The conditions here are perfect.

These are the largest, most pristine kelp beds in the world.

♪ The fjords and seaways of the far south stretch for thousands of miles.

Remote and rarely visited by humans.

[ Seal purring ] In 2003, scientists made a surprising discovery here in the heart of the Tierra del Fuego archipelago.

On this small island, they found an animal that was completely unexpected.

♪ One of the largest birds to take to the skies... [ Bird squawks ] ...albatross.

These giants normally nest on remote oceanic islands, not in narrow fjords surrounded by mountains.

No one knows why these black-browed albatross have chosen to settle here.

Exposed and steep, it's a challenging place to build a nest.

But every spring, 60 pairs return to their small dirt mounds.

[ Albatross squawking ] ♪ Black-browed albatross can live over 70 years.

This couple may well have been together for decades.

They only produce a single precious egg every year or two.

♪ ♪ The female could be away for days, even weeks.

And there's a chance she may not come back at all... ...because out at sea, there is something deadly.

♪ Narrator: This black-browed albatross father is keeping his precious egg warm.

♪ And he needs to sit tight.

A snowstorm is coming.

[ Wind whipping ] ♪ When the wind is this bitterly cold, leaving the egg for a moment might kill it.

♪ And in the far south, it can blow for days.

And days.

♪ [ Albatross squawking ] It's been a week since his partner left.

Cold and hungry, soon he will have no choice but to abandon his egg and feed.

♪ Finally, his partner returns.

♪ For now, their egg is safe.

And dad is free to search for his own food.

♪ Time to head for the open ocean.

♪ His wings, nearly 8 feet across, allow him to glide with almost no effort.

♪ ♪ He may travel hundreds of miles on a single feeding trip.

Riding the winds, he soars with barely a wing flap.

♪ But there's danger in the feeding grounds.

♪ Hooks -- often lethal for albatross.

Commercial fishing vessels trail hundreds of them on lines that can be over a mile long.

♪ Every year, thousands of albatross are hooked and drown.

♪ This longline fishing boat is different.

And not just because it's smaller, but because of its skipper -- Juan Carrasco.

[ Speaking Spanish ] ♪ Narrator: On a heavily weighted line, Juan's bait quickly sinks beyond the reach of the albatross.

[ Speaking Spanish ] This one may be hungry, but at least he's safe.

Narrator: Sometimes gatherings of albatross even guide Juan to good fishing spots.

[ Albatross squawking ] And in return, he gives them nutritious cast-offs from his catch.

♪ But perhaps the most incredible part of this story is how widely Juan's technique is spreading.

Prompted by scientists, the Chilean commercial longline fleet is now using Juan's heavy-weighted bait technique.

Hook-related deaths in Patagonia have dropped to practically zero.

It's an extraordinary conservation success story.

Juan's technique has even been adopted by other fleets across the rest of the Southern Ocean.

♪ While the rich waters of Patagonia's far south support an amazing diversity of sea life... ...the land appears desolate.

Much of it is a treeless steppe.

Only the very toughest animals can survive here.

♪ Narrator: Isla Grande, the largest land mass of Tierra del Fuego, covers 18,000 square miles.

This is the last land before Antarctica -- the very end of the world.

It takes a tough customer to survive here.

[ Sheep bleating ] Europeans introduced sheep around 150 years ago for wool and meat.

In summer, they graze on the hills.

But winter is coming.

♪ Freezing rain is forecast.

Shepherd Cristian Trina must get his sheep down to his lowland ranch.

All 1,200 of them.

♪ [ Trina speaking Spanish ] Narrator: If they get cold and wet, many could die from pneumonia.

To get to the lower pastures, they must cover more than 10 miles before nightfall.

Moving so many sheep is a tough job, but Cristian has some expert helpers.

♪ It's not an easy life, but Cristian loves it.

But times are changing.

Fewer young people are choosing this way of life.

[ Horn honks in distance ] And the modern world is taking over.

♪ A highway now runs alongside the old traditional trail Cristian uses for his sheep.

[ Horn blares ] ♪ ♪ Finally, the flock can move away from the road.

Their 10-mile journey is almost at an end.

The weather has held, and home is in sight.

♪ And just a few miles south from here, a remarkable animal is making a surprising comeback to Patagonia.

♪ The king penguin.

♪ ♪ ♪ [ Penguins chirping ] These are the only king penguins on the South American land mass.

Once, hundreds of thousands of them lived on Tierra del Fuego.

[ Penguins honking ] But they were hunted to extinction by European settlers.

It was only in 2010, unexpectedly, a handful of king penguins returned.

But the land's owner, Cecilia Durán, was not the first person to find them.

[ Durán speaking Spanish ] Narrator: Since that moment, she has dedicated her life to looking after these penguins.

Narrator: To keep them safe, Cecilia has built an enclosure around the penguins' breeding grounds.

Narrator: Visitors are kept at a safe distance.

Ticket sales fund research and conservation.

Cecilia is so devoted to protecting them, she is known locally as "the mother of penguins."

The colony may be small, but it's growing every year under the vigilance of its passionate protector.

♪ King penguins are under increasing threat from climate change and over-fishing.

So their unexpected return to Tierra del Fuego is something to be celebrated.

♪ But where prey goes, predators follow.

And a fearsome penguin hunter has arrived in Patagonia.

♪ ♪ Narrator: The San Rafael glacier.

Located in southern Chile, hundreds of miles north of the king penguin colony, it empties into an almost landlocked lagoon.

♪ Because of the steepness of this glacier and climate change, a lot of ice falls here.

♪ On average, a volume twice the size of the Empire State Building crashes into the lagoon every day.

And the fractured ice floes hide a formidable predator... ...a leopard seal.

Normally, they live and breed almost exclusively in the Antarctic... ...where penguins are one of their main prey.

♪ ♪ But in the San Rafael lagoon, more than 1,200 miles from Antarctica, there are no penguins, and it's a mystery how these seals are surviving here.

On a mission to learn more about them is national park ranger Nicolas Fernandez.

[ Speaking Spanish ] Narrator: Although Nicolas doesn't yet have the funds to analyze the seals' diet, he thinks he knows what they're eating.

Large numbers of Patagonian rock cod live just below the glacier wall.

[ Speaking Spanish ] Whenever there's an icefall, the leopard seals swim directly for it.

♪ Nicolas suspects the leopard seals are hunting fish scattered by the impact.

♪ But his biggest discovery has come from his observation of this particular seal.

Narrator: Nicolas has proved this is the most northerly established breeding population of leopard seals on the planet.

♪ In a world where so many large predators are disappearing, the arrival of this incredible hunter into new territory is remarkable.

♪ Narrator: Here in Patagonia's far south, life is making a comeback, returning home to habitats once abandoned.

Growing in number.

And even expanding into new areas.

There are still great challenges ahead.

But the people here love this place and the life it sustains.

With such passion and commitment, anything is possible.

♪ Next on "Patagonia: Life on the Edge of the World"... [ Bird chirps ] These are the forests that time forgot -- home to creatures both strange and wonderful.

Amazing things happen up in the trees.

♪