Explore the islands of the South Pacific with creatures like the spy koala, who captures breeding behavior in Australia, or the spy crab, who joins an army of red crabs on their march to the sea to deposit their eggs.
♪♪ NARRATOR: The animal worldis full of spectacle and wonder.
But what's it like to be right in the heart of the action?
To find out, our team of Spy Creatures goes undercover.
♪♪ They not only look like the animals they film, they behave like them, too.
♪♪ Armed with the latest camera technology... [ Bats screeching ] ...they are heading across the globe.
♪♪ [ Seals growling ] From the heat of the Tropics... ♪♪ ...to the lands that lie in the North.
♪♪ From the islands of the Southern Seas... ♪♪ ...to the snow and ice of the frozen poles.
♪♪ Our spies reveal the astonishing variety of life that thrives there... from inside their world.
♪♪ ♪♪ NARRATOR: On this assignment, our Spy Creatures reveal how life thrives on the islands of the Southern Hemisphere.
Far from the mainland, these isolated places have given rise to some of the most unique animals on Earth.
The Galápagos Islands of the Pacific Ocean.
A barren archipelago formed by underwater volcanos some three million years ago.
This landscape of lava is home to a remarkable fauna, found nowhere else in the world.
♪♪ One of the most intriguing is the marine iguana.
♪♪ Before they can become active, these cold-blooded lizards must bask in the sun.
Their black skin absorbs the heat, raising their core temperature to a toasty 100 degrees.
To film these highly protected animals, Spy Iguana has special permission to go closer than any human is allowed.
To succeed, it has to be totally convincing.
Once they are hot enough, they start to move.
♪♪ Spy Iguana now witnesses something remarkable.
♪♪ Cliff jumping for lizards!
♪♪ ♪♪ They are after the seaweed that flourishes just offshore.
♪♪ They're on borrowed time -- the water is cold, and in less than an hour, their body temperature will drop by half, and they'll have to return.
♪♪ Now another spy takes over.
Lava Cam can track the iguanas wherever they go.
At this time of year, the females are laying their eggs on the beach.
The sand is baking hot, but three feet down, it's the perfect temperature for incubation.
Spy Iguana joins them for a closer look.
Digging the nest can take an hour, hard work in the hot sun.
When they take a break,they have a self-styled sun hat!
♪♪ Even our spy!
♪♪ Competition for the best nest sites is intense.
Those digging must be prepared to hold their ground.
Head-bobbing is a challenge for ownership.
The winner is decided by a test of strength.
♪♪ ♪♪ ♪♪ The owner wins.
She's free to finish her work.
Along the tide line, the others are returning from their underwater feast.
Chilled through by the cold sea they must sunbathe once more.
As Spy Iguana joins them, another surprise is in store.
They sneeze snot!
Special glands in their nose remove excess salt, which is expelled spectacularly!
Whatever they can do, our spy can do, too.
♪♪ Mm... perhaps not.
As the day ends, iguanas show their more affectionate side.
Even our spy has an admirer.
♪♪ Snuggling together preserves precious warmth, as the sun sets over the Galápagos Islands.
[ Birds chirping ] Over 8,000 miles away, off the southern coast of Australia, Kangaroo Island is another unique wildlife haven.
Cut off from the mainland for 10,000 years, it even has its own variety of kangaroo.
Koalas are here, too,but they are relative newcomers.
Introduced here 100 years ago, they now survive in unrivaled numbers.
Among them is a new koala, fresh from the mainland.
♪♪ It's here to film their breeding behavior.
♪♪ The timing's perfect -- they're just waking up.
Yawning pumps oxygen to the brain.
Even wide awake, he needn't go far.
His favorite food is all around him -- Eucalyptus.
But their leaves are not only tough, they're poisonous.
So koalas have powerful digestive juices that neutralize the toxins.
Just digesting their food saps energy, so they sleep up to 23 hours a day.
But today, this koala is breaking the habit.
In the breeding season, he must take it up a notch.
One of our mobile spy camsmust also rise to the challenge.
Koalas rarely come to the ground or show such a turn of speed.
♪♪ But he now has a territory to defend.
[ Koala bellowing ] He bellows to announce he's in charge.
A warning to other males.
Koalas scent mark the ground to tell each other who's been passing through.
He's caught the scent of a female.
But this one already has a baby.
No point chasing her.
But she's not the only female here... and our spy is now keeping her company.
♪♪ The male's enthusiasm may be short-lived.
A rival has found her first.
He will have to challenge for possession.
He announces his arrival with a warning.
[ Bellowing ] Spy Koala is witnessing something rarely filmed -- a fight in the treetops.
[ Koala screeching ] The only injury -- a loss of dignity.
The loser makes his retreat... ...while the challenger gets the girl.
For all, that's quite enough activity for one day.
Christmas Island in the Indian Ocean.
Home to a creature found almost nowhere else on Earth.
Every year, the monsoon rains sweep the island and trigger a mass awakening.
Spy Crab is ready to capture what's about to unfold.
The real crabs have been sealed in their burrows for months, avoiding the worst of the yearly drought.
Now they emerge en masse.
♪♪ Each female, carries thousands of eggs in a protective pouch beneath her belly.
United by a common goal, they begin their march to the sea.
The few soon become an army.
♪♪ They haven't eaten for months and are hungry for anything they can find... ...sometimes even each other!
But a robotic crab won't satisfy anyone's hunger!
All in working order, Spy Crab rejoins the march to the sea.
♪♪ ♪♪ Since human settlers arrived, the crabs have faced hurdles never found in nature.
The smallest try to squeeze through.
The rest have just one option -- to climb.
No problem with six powerful legs to help.
♪♪ ♪♪ ♪♪ Once down, an even greater challenge awaits them.
[ Horn blares ] Many roads close in the migration season, but not all.
[ Crunch ] There are always some that never make it.
But here, it's a case of waste not, want not.
Now it's Spy Crab's turn.
♪♪ ♪♪ ♪♪ ♪♪ Against the odds, most make it to the coast.
They assemble in the shade waiting for the perfect moment.
High tide triggers the final push.
♪♪ ♪♪ Then, in the thousands, they release their eggs.
A victory dance speeds the process.
♪♪ ♪♪ Each crab may release 100,000 eggs, all swept out by the retreating tide.
In four weeks' time, their hatchlings will return to the island.
[ Birds chirping ] Madagascar.
Bizarre baobab trees are a remnant of the island's ancient connection to Africa, now 300 miles west.
It was once connected to Asia, too.
Separated from both for millions of years, life here has taken its own evolutionary course.
In the island's spiny forest, 95% of plants exist nowhere else on Earth.
And the animals are equally unique.
♪♪ A sifaka lemur.
One of over 100 different species found only here.
♪♪ Madagascar is also home to half the world's species of chameleon.
♪♪ One of the most beautiful is the panther chameleon.
This one's a spy.
He's staring down a warty chameleon.
To their own kind, they are fiercely territorial.
But not, it seems, to our spy.
While our chameleon is otherwise preoccupied, another takes over.
It's soon spotted by another lemur.
They spend more time onthe ground than any other lemur.
They are also intelligent and curious.
Anything new demands a second look.
♪♪ Lemurs are sun worshippers.
Adopting the lotus position helps raise their body temperature... ...vital for an animal with a low metabolism.
♪♪ They're very good-natured, even to those that steal their sun.
♪♪ ♪♪ After half an hour's meditation, the day begins.
They live in large groups up to 30 strong.
Their tail acts as a flag, making sure no one gets lost.
While ringtails spend most their time on the ground... ...sifakas spend most of theirs in the trees.
Their powerful legs and stabilizing tails help them leap more than 30 feet.
Adapted for jumping from tree to tree, they have trouble walking on all fours.
They have a unique solution.
♪♪ How better to cross open ground?
♪♪ ♪♪ ♪♪ It may not be conventional, but it's surprisingly quick.
In just a few seconds, they can be gone... ♪♪ ...leaving our spy with those who prefer life in the slow lane.
Back on Kangaroo Island, it's now the breeding season for the animals that gave the island its name.
This type of western gray kangaroo is smaller and stockier than its mainland relatives.
They, too, hang around in groups known as mobs.
Each consists of up to 10 females and their babies, called joeys.
Every mob has an adult male, known as a boomer, keeping an eye out for them.
Now there's a newcomer in their ranks.
The boomer checks out any new member of his gang.
She looks the part.
That's good enough for him.
Inside the mob, females often act as aunties to each other's joeys.
♪♪ One joey has taken a shine to Spy Roo.
[ Sniffing ] He seems to regard her as an auntie, too.
Then, as the ultimate sign of acceptance, he even tries to suckle!
Despite the apparent harmony, there are dangerous rivalries here.
Competing males are everywhere, hoping to steal a female.
♪♪ ♪♪ Their liaison is no longer a secret.
♪♪ It's something no boomer can tolerate.
First a bit of shoving.
Then the claws are out.
♪♪ His mob can only watch from the sidelines.
♪♪ ♪♪ ♪♪ Now for the big guns.
The kick can deliver a blow of over two tons.
♪♪ Victory, for now.
♪♪ But the boomer must always stay on guard.
Meanwhile, peace returns.
♪♪ ♪♪ And the joey's adopted auntie is the center of attention once more.
♪♪ Just off the coast of South Africa lies a small outcrop known as Seal Island.
♪♪ Cape gulls are common here, but this one has a camera in its eye and belly.
Below are the Cape fur seals that gave the island its name.
More than 60,000 of them.
They feed on the vast fish stocks that thrive in the cold Antarctic currents.
At this time of year, they gather to raise their young.
Among them is a spy.
He can sneak right up close without raising suspicion.
Touching noses shows they are totally at ease.
All around, the pups are growing fast.
Fed on their mother's full-fat milk, they quickly outgrow their island home.
Everyone is squabbling over space.
Soon, they must venture into the water, including our spy.
♪♪ Female seals are known to adopt orphans.
Perhaps this is why Spy Seal is creating interest.
♪♪ He's also a welcome playmate to the younger seals.
♪♪ ♪♪ But in nature, danger is never far away.
Spy Gull is patrolling the waters around the island.
Below, the ocean's greatest predator -- a great white shark.
Each year, over 40 gather here to hunt the young seals.
Spy Seal is the first to see the shark approach.
♪♪ ♪♪ ♪♪ But one young seal is still blissfully unaware.
Until a game of cat and mouse unfolds.
♪♪ ♪♪ The seal may be young,but he's quick and maneuverable.
♪♪ Seen from above, something remarkable becomes clear.
The seal pup can turn faster than the shark.
He deliberately gets behind it, out of sight.
Whenever the shark turns, the seal stays right on its tail.
♪♪ Until, finally, he makes his escape.
♪♪ Our spy is now the only seal remaining.
♪♪ The shark begins to circle.
Checking out yet another likely target.
Sharks can detect minute electric fields.
Spy Seal has plenty of those.
At every pass, it gets closer.
The first bite is exploratory... ...testing if it's a worthwhile meal.
Sharks have a highly developed sense of taste.
This wasn't what it was looking for.
Battered and bruised, Spy Seal is left alone.
But it's a long way back to the island.
♪♪ Over 5,000 miles away, off the coast of Western Australia, is Rottnest Island... home to one of the most photogenic creatures on Earth.
♪♪ Meet the quokkas, the only native mammals to live here.
These marsupials have no other living relatives and exist only in a few places in Australia.
They have a friendly reputation... ...so our spy should fit right in.
It's all going according to plan.
As few predators are found on the island, they are curious and welcoming.
[ Sniffing ] Spy Quokka's mission is to find out how they raise their young.
Quokkas are vegetarians, and tea tree is one of their favorites.
Behind their cute smiles are some razor-sharp teeth, and they use their five-fingered hands for grasping.
Quokkas eat so much vegetation, they rarely need to drink.
But this is what our spy has come to see.
♪♪ A baby quokka.
A joey -- just 3-months old.
All marsupials carry their babies in a pouch.
Quokkas are no exception.
For the last 3 months, he's relied on his mother's milk.
Now he's trying solid food, but, as a result, he's getting too big for his pouch.
♪♪ Withholding food is one way to deal with the problem.
It's already quite a squeeze to get out... but there's a big wide world to explore.
♪♪ He's going to need a lot of looking after.
♪♪ ♪♪ ♪♪ Our spy now witnesses another side of quokka life.
For all their cuteness, quokkas will fight over food.
Especially tea tree.
♪♪ Even the joey's mother isn't keen to share.
♪♪ With all this competition, Spy Quokka is on dangerous ground.
♪♪ [ Sniffing ] A peace offering.
That seems to have done the trick.
♪♪ For the baby, it's been quite enough adventure for one day.
♪♪ ♪♪ ♪♪ Across the Indian Ocean, on the remote island of Komodo, the east winds are blowing.
They bring the dry and harsh conditions that trigger the breeding season for the infamous Komodo dragon.
Unique to these tiny Indonesian islands, they are the largest lizard in the world -- up to 10 feet in length.
The forked tongue is used to detect odors.
This male is seeking a mate.
Spy Dragon looks just like the real thing.
♪♪ Certainly worth a closer inspection.
♪♪ He rakes his claws over the skin to try to release pheromones to reveal its sex and age.
Then checks with his tongue.
♪♪ She may look the part, but she doesn't smell the part.
There's nothing of interest here.
He heads to the water hole -- always a good meeting place at this time of year.
Here, Spy Pig is also on duty.
As wild pigs are often eaten by dragons, it soon attracts interest.
Again, he uses his tongue to check its scent.
But there is something far more interesting on the wind.
A real female dragon.
Some wooing is required.
His advances are captured by a Mud Cam.
She stops to show she's interested.
This time raking the skingives off all the right signals.
Our spy captures what must be the closest dragons get to a tender moment.
But pheromones travel far -- another male is also on the scent.
With testosterone raging, a fight is inevitable.
♪♪ The female has a vested interest in the outcome, so follows behind.
They test their strength by wrestling.
♪♪ ♪♪ The victor pins his rival to the ground... ♪♪ ...and finally chases him off.
But with everyone in a fighting mood, Spy Pig is no longer quite so safe.
♪♪ ♪♪ ♪♪ The other dragons are showing interest, too.
He may be down, but he keeps on filming.
At nearly 200 pounds, these dragons are 10 times heavier than their victim, and they've hardly even started.
♪♪ ♪♪ ♪♪ For the first time ever, a view inside a dragon's mouth.
One laden with venom and toxic saliva, dosed with over 50 types of deadly bacteria.
But as Spy Pig doesn't taste edible, he's soon abandoned.
Anyway, the dragons still have romance on their minds.
Spy Pig's days are well and truly over.
While our friendly dragon survives unscathed.
♪♪ Back in the Galápagos Islands, the moss-shrouded mountains of Santa Cruz set the scene for another remarkable gathering.
♪♪ Boulder Cam is on a mission tofind this rare and secret event.
♪♪ It's not long before it finds the first hopeful sign -- a giant Galápagos tortoise.
Unique to these islands, and at nearly six feet head to tail, they are the biggest in the world.
In these moist mountain valleys,there is plenty for them to eat.
But plants are so tough and fibrous, they must feed for eight hours a day just to get enough nutrients.
It's not the only tortoise here.
There's a spy in disguise.
It's the breeding season.
Spy Tortoise could be just what he's looking for.
♪♪ Although he's never come across a female like this before.
♪♪ ♪♪ With 800 pounds on her back, it's a good thing her shell is reinforced.
♪♪ ♪♪ [ Record scratches ] Well, that was never going to work!
But he soon picks up the scent of a real female.
With both spies hot on his heels.
He would have smelled her from over a mile away, a useful skill in such a dense forest.
[ Tortoise bellowing ] It's now just a case of following the sound.
Mating can last for hours.
It never ends gracefully.
Finding a mating pair is quite an achievement, but our spies have yet to complete their mission.
But this is a hopeful sign.
In fact, Galápagos tortoises are everywhere!
And here it is, their Shangri-La -- an incredible gathering of over 30 giant tortoises.
♪♪ All enjoying the fresh water found in just a few mountain pools.
[ Bellows ] ♪♪ It's a haven for other wildlife, too.
The Galápagos pintail duck.
[ Chirping ] For the tortoises, the pools not only offer a place to drink and chill, but to absorb the food they've eaten.
Our spies' mission is finally complete... leaving the tortoises to digest their high-fiber meal.
♪♪ Next time... our Spy Creatures venture to the Poles to find the extraordinary animals that thrive in a world of ice and snow.
♪♪ ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ NARRATOR: To learn more about what you've seen on this 'Nature' program, visit pbs.org.