Original subtitles

An ancient tale foretells that our planet

and its future rest on a turtle's back.

If we lose the turtle,

there would be no earth,

No US.

Today, the story of a sea turtle's life is just as profound.

On Australia's Great Barrier Reef,

there's a tropical beach

where one tiny turtle's big adventure

is about to begin.

This is Bun“.

She's a green sea turtle

and today is her birthday.

Out of the hundred eggs she shared a nest with,

She's the very last hatchling to emerge.

It will take Bunji a few days to make it above ground,

and join the other newborns

making their way to the water.

And when Bunji finally breaks free,

she too has to make a run for the ocean

Up where she comes from,

Bunji is an indigenous Australian word for friend.

And she needs one,

because the first thing a baby turtle sees

is something that wants to eat it.

Bunji's parents are roaming the ocean,

meaning she'll have to fend for herself.

The odds are against her.

And as if the birds weren't enough,

ghost crabs haunt the water's edge.

Bunji's going to need all the luck she can get.

But it's not much safer in the water.

Just one in every thousand hatchlings

will survive to maturity.

It will take all of Bunji's turtle instincts

to make it through, in one piece.

Sea turtles have an amazing ability to...

Oh. Mm.

Phew. And all that in just the first five minutes.

If Bunji makes it to adulthood,

she could live to be over 100 years old.

And in that lifetime,

she will swim many thousands of miles,

meet incredible creatures,

and have some really wild encounters.

Welcome to Turtle Odyssey.

It's Bunji's first night in the vast ocean.

She is small and all alone.

It's all a bit spooky.

She must learn where danger lurks.

Unlike this cuttlefish,

Bunji isn't as easily camouflaged.

She must discover who's friend,

who's foe,

and who's just passing through.

Let's hope she gets it right.

Bunji is following her instincts to swim out to open water,

just like marine turtles have for millions of years.

Sea turtle highways criss cross the oceans.

Tracking the seven different species reveals

it's a turtle planet.

In their lifetime, some turtles, like the leatherback,

will travel over half a million miles,

that's like swimming to the moon and back.

Little Bunji is now 300 miles off the east coast of Australia,

a long way from where she was born.

For years,

no one knew where baby turtles went

or how they travelled across the great oceans

until now.

It turns out they were hitching rides on rafts of seaweed

and Bunji's found one.

Below, reef sharks and other large fish prowl.

All hungry for a tasty turtle treat.

But Bunji is happy in her floating fortress.

It's safe and warm, and if she's hungry,

she can even take a bite.

Bunji will catch many of these free rides.

As the years go by,

she'll be carried along by the ocean currents.

She'll get bigger,

and bigger,

and bigger.

Until she's so big,

she's large enough

to leave her seaweed sanctuary

and continue her journey swimming out across the open sea.

Bunji is now a teenager, with attitude.

Because of her bigger size, and hard shell,

she's tough enough to head back to the shallows.

Bunji is now over 600 miles south

from where she was born

and has found a pacific island paradise.

This is the remote Lord Howe island.

Here, the rich East Australian Current

lifts cool waters from the sea floor

packed with nutrients.

They mix and collect in the lagoon,

it's teeming with life.

Coral reefs support millions of species.

This is one of the most bio-diverse ecosystems

on the planet.

The perfect place for Bunji to take a bit of a break.

And have a snack.

Although she has no teeth, her beak is perfect

for pecking tiny algae off the coral.

Keeping the coral clean

makes turtles a keystone species

as countless other species depend on healthy coral

for their survival.

She also eats sea grass,

lots of it.

Unlike some teenagers,

Bunji loves her greens.

She's got a big appetite.

Luckily, all this turtle trimming

allows fresh shoots to grow.

It's just another way she keeps the ocean healthy

and creates a perfect pasture

for one of the ocean's most mysterious creatures.

The lives of dugongs and turtles are intimately linked,

part of a much larger ecosystem

where one species depends on another.

These dugongs, or sea cows, are fortunate.

They love eating the roots exposed

by the turtle trimming.

As the years pass,

Bunji loves to munch on something else

in this pacific island lagoon.

It's a sea salp.

Sea salps look like blobs of jellyfish,

but they're not.

They're one of the oldest creatures in the sea,

one of the first to develop a central nervous system.

They're an ancient ancestor of almost

all complex life on the earth,

including us,

and Bunji finds them rather tasty.

Bunji has been feeding up

for her long journey ahead.

Now an adult,

she's feeling the call to leave her island paradise

and head toward the mainland

across the vast open sea.

It's an incredible journey of over 500 miles.

The ocean covers over 70% of our planet.

It's the world's richest environment,

yet in places seems completely devoid of life.

Bunji will swim through these watery deserts alone.

When she does meet other creatures,

they'll be travelling in groups.

It's a smart evolutionary survival strategy.

After all, there's safety in numbers.

Traveling the ocean solo

Is a risk she'll have to take.

An ancient instinct is calling Bunji.

There's still a long way to go,

but she is exquisitely evolved for undersea travel.

Her buoyancy is so fine-tuned,

she moves with the absolute minimum effort.

Perfectly balanced, she is weightless in her water world.

Sea turtles cruised the ancient oceans

over 100 million years ago.

Since then, they have remained anatomically unchanged.

Bunji is prehistoric perfection, on a mission.

Strangely, for such an ancient creature,

the biggest threat to her survival

is a relative newcomer.

Humans.

From traditional fishermen catching them with their hands,

to commercial fishing vessels

often catching them as unintended

bycatch in their thousands,

a quick getaway speed is her only defense.

There's still much work to be done

to protect turtles from humans.

In the last four decades,

the number of turtles injured by boats has tripled.

And one new threat is looming ever larger.

In the stomachs of half of all sea turtles

is plastic waste, and it's really hurting them.

Turtles have a problem telling the difference

between plastic and one of their major food sources,

jellyfish.

Don't eat it, Bunji.

If no action is taken,

soon there will more plastic in the ocean than fish.

Thankfully, some people have dedicated their lives

to protecting sea turtles.

Dr. Ian Bell is a turtle hero.

He leads a special task force

for the Queensland government.

It's called the Threatened Species Unit

and today, they're catching and tagging turtles

to find out more about them.

Combining data from government agencies and thousands

of volunteers from around the world,

they've discovered a staggering fact.

There are now only half as many sea turtles

in the ocean as there were 100 years ago.

This small tag will be a big help,

providing data to scientists and volunteers

trying to save her species.

Dr. Bell has discovered that as earth warms,

it's changing the temperatures of the beaches

where turtles nest, and that has him concerned.

Because if turtle eggs are laid in extra warm sand,

all the hatchlings will be girls.

Less male partners puts the entire turtle species at risk.

Bunji's ocean home is where complex life began,

and on which most life still depends.

Now fully grown, this truly is her world.

A world we have barely explored.

Filled with wild creatures

that are both weird

and wonderful.

Whose complex relationships to each other

we're only beginning to understand.

We know more about the surface of Mars

than what's hiding out on our ocean floors.

Who knows what biological wonders

are yet to be discovered?

The ocean is our greatest treasure

and our greatest responsibility.

And the remarkable recovery of one species

provides hope for the continued survival of the turtle.

From the deep, a behemoth arises.

Migrating south, this humpback whale mother and calf

cross Bunji's path.

They're heading to the rich feeding grounds of the Antarctic.

This big baby weighs in at over 3,000 pounds,

so Bunji would be wise to keep her distance.

These whales were once critically endangered,

hunted almost to extinction.

But then humans heard their cry for help.

Along the east coast of Australia,

humpback whale populations have made a full recovery.

If we did it for these whales,

maybe we can still do it for the sea turtles.

Let's hope so,

because entire ecosystems rest on a turtle's back,

and that means an ocean without turtles

would be a very empty place.

As the whales travel south,

other animals like Bunji

are heading north to warmer waters.

Dolphins, whales and turtles have been travelling

these water highways

long before humans walked the earth.

Catching her breath at the surface

is where Bunji is in most danger.

From below,

she stands out

like a turtle target.

This could be a bad day for Bunji.

Sharks eat turtles.

This great white shark is over 16 feet long

and could easily make a meal

out of a fully grown turtle.

Bunji is in real danger

but she has a plan.

She takes evasive action,

turning her tough shell towards her attacker,

diving deep to the sea bed.

Down here, she's camouflaged against the coral.

To limit their time at the surface,

turtles have evolved the ability

to reduce the amount of oxygen they need.

They do this by slowing their heartbeat down

to one beat every minute.

And that means a green sea turtle

can stay underwater for over six hours.

But Bunji can't stay here forever.

As a cold-blooded reptile,

she needs to return to the surface and warmer waters.

It's time to catch some early morning rays.

Some turtles even leave the water for a spot of sunbathing.

It's often the larger males that are the sun loungers.

This beach boy will catch rays all daylong.

He's not aware that soon he'll play

an important part in Bunji's epic odyssey.

As for Bunji, time is ticking.

She must get ready for her big day,

but first she has to make a quick stop.

Over 100 different species can be found

living on green sea turtles.

The parasites help keep her camouflaged

but they also slow her down and can be quite itchy.

It's time to get some off,

but how do you do that with flippers for fingers?

She's looking for something special.

The right spot with the right sort of fish.

These parrotfish are too big,

and these chromis fish are too small.

Ah, but these tangs are just right.

Bunji has found a cleaning station.

It's a place where smaller fish feed off the creatures

living on larger animals.

This is known as a symbiotic relationship.

It's win-win.

The little fish get fed,

and the larger animals like Bunji get cleaned.

Everybody's happy.

And with a shell as sensitive as a human fingertip,

she also likes a good scratch,

and a scratch,

and a scratch.

But Bunji's not the only one who likes a good scrub.

A squadron of rays is about to hit the station.

These bad boys can have a wingspan

of over twenty feet,

and weigh up to 3,000 pounds.

That's the same as an average family car.

So when these guys arrive,

they go right to the front of the line.

And that means smaller fish, like this batfish,

get bumped to the back.

Because in nature,

size really does matter.

But Bunji doesn't have time to wait.

As the currents pick up,

she's being called to her final destination.

But forces of nature are rising against her.

Bunji struggles.

Even below the waves, the currents swirl around her.

With low visibility,

Bunji is using an invisible force

to guide her to a very special place.

Bunji's brain can actually detect

the magnetic fields of the earth.

Every place on the globe has a unique magnetic fingerprint.

Bunji uses this information like a map.

As she gets close, her map matches that

of her current location.

At last,

she's reached her destination.

She's home.

After 25 years at sea,

she's come back to the very beach she was born on.

And she's not alone.

The Great Barrier Reef is host to the biggest

green sea turtle rookery in the world.

Bunji's big adventure is one shared

by thousands of other turtles.

All around the world,

green sea turtles are making similar great migrations

to the beaches where they were born.

So, this family of turtles

may have been coming back to this very beach,

generation after generation,

for thousands of years.

It's one of nature's most astonishing family reunions.

Now it's Bunji's turn to play her part

in that larger turtle story.

It's time for Bunji to find a boyfriend.

Once Bunji has mated,

she will remain close to shore for over a month.

Then, when the time is right,

she'll undertake her most important task.

It's time for Bunji to leave her water world.

It will be her toughest turtle trial.

After a lifetime of weightlessness in the ocean,

gravity really sucks.

Weighing in at 250 pounds,

Bunji has to struggle up the same

strip of beach that, decades before,

she scurried down.

She'll spend the next few hours

digging herself into the sand,

and scooping out a chamber for her eggs.

It's exhausting work for this soon-to-be-mother,

but her instinct is unflagging.

She'll bury her eggs in the same sand

her mother did over 25 years ago.

The warm sand will keep them safe

for the next two or three months.

Finally, she covers her nest with the gentle care

that only a mother can give.

Laying five or so clutches every few years,

she will produce thousands of offspring in her lifetime.

After along night,

she'll return to the comfort of the sea.

She'll be back,

but for now,

her odyssey is complete.

Three months later, another chapter

in the turtle tale begins.

A new generation of tiny turtle toddlers are popping up.

It's time for Bunji's little babies

to take on the challenges of the turtle odyssey.

♪ I'm walking on sunshine ♪

♪ I'm walking on sunshine ♪

♪ I'm walking on sunshine ♪

♪ And don't it feel good ♪

♪ And don't it feel good ♪