Original subtitles

Dolphins. The cleverest creatures in the ocean.

They may seem familiar, but their undersea lives are a mystery.

Spy creatures explore their hidden world...

..discovering amazing abilities...

..and strange gatherings.

Revealing their intimate relationships...

as well as their conflicts.

Discover the intelligence of these fun-loving creatures...

...and enter their lives as never before.

In the sea off Mozambique is a secret world.

It's home to the bottlenose dolphin,

the most widespread and best-known dolphin in the world.

Despite their familiarity their life below the waves is steeped in mystery.

But all this is about to change.

For here, even a giant clam is not quite as it seems.

And these super smart dolphins are suitably intrigued.

They know that this clam is like none they have ever seen before.

(Chattering)

These are nautilus, alien creatures from the deep abyss.

But these are organisms of a very special kind.

For their eyes are state-of-the-art cameras.

Nautilus soon meets the long probing nose that gives these dolphins their name.

Bottlenose dolphins have excellent eyesight but they have another way to see.

They can beam sound waves from their forehead.

(Clicking)

And use the returning echoes to create a picture in sound.

This sonar penetrates like an X-ray.

(Chatters)

There's nothing to eat in here!

The dolphins are so completely at ease with Spy Nautilus,

a mother is happy to reveal her own precious secret.

Her newborn baby, just five days old.

He still bears wrinkles from his time curled up in the womb.

His mother can stay down for 15 minutes, but he must breathe every two.

So, for his first few weeks of life, she makes sure he's only a few metres from the surface.

He has been born into an extended family made up of aunts and other females.

Each dolphin has its own unique signature whistle that it uses just like a name.

(Whistling)

The baby will learn these whistles and soon recognise each and every dolphin.

Pod members come and go,

but their enduring friendships are strengthened by touching and tickling each other.

As well as an underwater version of cuddling.

For mother and baby close physical contact is an essential part of their relationship.

For the next two years they will never be apart.

Further along the Mozambique coast another spy creature has appeared.

This is Spy Turtle.

He is keeping his beady camera eye on another group of bottlenose -

this time a pod of males.

Dolphins are intrigued by this strange but harmless turtle,

so it can easily film them when they come to the surface.

It can also watch their activities beneath the waves as well.

No other spy creature has such a perfect overview.

Male dolphins live mostly bachelor lives away from the females

and their life is sociable and happy-go-lucky.

Like the female pod, males come and go, but there is always a core "band of brothers",

who can be friends for life.

To film their energetic and carefree lifestyle Spy Turtle will have to shift up a gear.

He does his best to keep up.

But he's soon outperformed.

All dolphins love to leap but these boy racers love it more than most.

The best can jump nearly six metres.

Some can really do it in style!

Across the world, off the coast of Central America, lives an even more energetic dolphin.

To film their high-speed antics, a new and faster spy creature joins the team.

Spy Dolphin reaches 15 miles per hour and also has HD cameras for eyes.

But he'll have his work cut out -

these spinner dolphins can easily travel 250 miles in a single day.

And he soon discovers just why they're called spinners.

They are curious about Spy Dolphin.

As they jump, they sneak a peek at their strange travelling companion.

To film underwater another super-fast spy creature enters the fray.

Spy Tuna can rapidly infiltrate these dolphins.

And use the camera in her mouth to capture the first ever images from inside the pod.

She soon discovers that what Spy Dolphin saw at the surface was just the tip of the iceberg.

(Chattering)

Although dolphins normally travel in small groups,

they sometimes come together in spectacular numbers.

This is a super pod - made up of hundreds upon hundreds of dolphins.

But it's not Spy Tuna's only revelation.

She soon discovers just how their extraordinary leaps are performed.

Rapid beats of the tail provide the power.

While twisting starts as they leave the water.

Sheer muscle drives their spectacular aerial display.

No other dolphin accomplishes these astonishing corkscrews.

Back in Mozambique, the young dolphin is off on his first adventure.

Stingrays are a common sight.

His mother uses warning calls to teach him to avoid the sting in their tail.

But it seems this is not just a passing ray.

Something far more mysterious is happening.

The stingrays are gathering together.

The dolphins join in:

their unrivalled knowledge of ocean life tells them that this entourage is well worth following.

Leading them is an extremely rare, small-eyed stingray - the biggest stingray in the ocean.

Shadowing the rays are cobia fish.

These renowned scavengers confirm that a meal is on its way.

This is the first time such an extraordinary gathering of sea creatures has been recorded,

but to the wordly-wise dolphins it must be a common sight.

It's an early lesson for the new baby, but he'll have to hold his breath.

He's learning that rays possess a unique skill - one that might lead them to a meal.

On the ray's underside is an array of electro sensors.

These detect the minute electrical discharges given off by other animals,

even those buried in the sand.

When the ray senses a hidden fish it stops and sucks it into its mouth,

while all the followers can do is scramble for scraps left behind.

But dolphins are smarter.

Having used the rays as guides to the best fishing grounds,

they then deploy their own super-senses to find the buried treasure.

Their sonar penetrates the sand and bounces off the hidden meals.

(Clicking)

The baby has sonar too, but he's still just trying it out.

(Chatter and clicking)

His mother's domed forehead, known as the melon,

concentrates the sound waves into a beam.

The returning echoes reveal the shape and type of any hidden fish.

Some make a dash for it...

..but there's always plenty more fish in the sea.

(Clicking)

She tries again.

By increasing the speed and intensity of her clicks, she can search deeper into the sand.

And a concentrated blast of sonar can even stun the fish.

(Clicking intensifies)

Success at last!

It's not a moment too soon for the baby dolphin.

He's held his breath for a record-breaking three and a half minutes!

He now gets his own reward.

The milk from his mother's watertight pouch is six times richer than cow's milk.

Reared on this nutritious diet, he'll double in size in just one month.

By shadowing his mother, the calf learns hunting methods

unique to catching fish in his local area.

Like so many things in a dolphin's life, the knowledge that rays are a good guide to a meal

is handed down from mother to calf.

And the same intelligent learning is also seen among other dolphin pods throughout the world.

The shallow waters of the Florida Keys create a very different challenge for a bottlenose dolphin.

The way they catch fish is even more inventive.

(Whirring)

It's a perfect mission for Spy Dolphin.

But he won't be working alone.

Beneath the waves, a new spy creature joins the underwater menagerie.

Spy Ray: a creature that glides along the bottom

as it follows the dolphins across the sea grass.

Its subjects have devised an extraordinary hunting technique

especially for these conditions.

It starts when a dolphin deliberately beats his tail to stir up a plume of mud.

Covering the unsuspecting fish, as well as Spy Ray.

He soon forms a U-shaped mud plume.

And then ploughs through the cloud, catching any fish confused by the sudden blackout.

He's chasing ballyhoos - one of the fastest reacting fish in the sea.

But the dolphin's sonar can see right through the mud while the fish can't see her coming.

Usually, the dolphin wouldn't stand a chance with these fish,

but by using his intelligence to create a mud screen he regains the advantage.

Further along the Keys,

the spy creatures discover that when dolphins cooperate to use the mud

they can achieve even more success.

By working as a team they have devised a way to hunt mullet.

One member of the pod races ahead of the shoal

and again beats her tail to create a mud wall.

But this time she creates a complete circle, entrapping the fish inside.

As the mud-ring spreads, the mullet try to escape the trap -

leaping into the mouths of the waiting dolphins.

Once all of the fish have jumped, the dolphins start again, forming a new mud ring.

The dolphins then wait for the next fish eruption.

Spy Dolphin noses closer to take up a ringside seat.

The youngsters learn the art of catching by watching the experts.

These unique techniques are only known by dolphins local to these shallow waters,

and these skills are passed on from generation to generation.

When they've caught all they need it's a chance to show-off.

Back in Mozambique the pod of females are skirting the coast looking for their next meal.

This time they are after another local delicacy that requires yet another tactic.

Fish shoals are surprisingly noisy,

and dolphins can hear the sounds they make from ten miles away.

Nautilus is among the many spy creatures watching the dolphins' plan unfurl.

(Rustling and crackling)

The youngster is over a month old now and can stay down for longer,

but diving deep is always a great adventure.

They are hunting huge kingfish.

Some reach over a metre and weigh 15 kilos.

They are far from easy to catch.

The young dolphin is still only an observer,

but this is how he learns the skills needed later in life.

The dolphins take their time.

They know they can't outpace the kingfish,

so their idea is to scan each fish with sonar and select only the weakest, slowest individuals.

And there it is!

She's found her target and gives chase.

It's a big catch.

A nursing mother must eat 15 kilos of fish a day,

so just one kingfish can provide all her daily requirements.

She heads back to the depths.

And Spy Ray soon discovers the reason.

They use the seabed to help break the fish into smaller pieces.

It's another new discovery for the spy creatures.

But more revelations are in store.

Killing such big fish has unexpected consequences.

The parasites of their prey have jumped ship and attached themselves to the dolphins.

Even the young dolphin has acquired an unwelcome hitchhiker - just beneath his eye.

It's a remora: a suckerfish that lives by eating the dolphin's leftovers.

They skip around like an aquatic fly.

But they're even more irritating than a gnat, and far harder to get rid of.

The dolphins know a few tricks.

Using the seabed to scrub them off is a good start.

The youngster has a go.

(Whistling)

Then tries again.

But whatever he does, the pesky remora stays on board.

Even when he has to take a breath.

He tries a different tack.

Rubbing it against an unsuspecting dolphin.

But has better luck with his mum.

She accepts the unwelcome gift as only a mother can!

Back in the Pacific Ocean,

the spy cameras are finding that the spinners' extraordinary leaps

might help them deal with their own remora problem.

As a spinner leaps, it's clear that she too has a remora attached to her belly.

By twisting violently she makes it hard for any hangers-on to stay on board.

Most spinning dolphins have these unwelcome guests

and it's likely that many are dislodged on impact.

But they leap so persistently there must be other reasons too.

Possibly it's a long distance signal that helps keep the pod together.

But dolphins turn everything into a game and spinning soon becomes a competition.

Practice starts at an early age.

A cautious start.

Then a spectacular leap, but without the spinning.

Getting better.

Better still.

This is more like it.

Finally, a jump to be proud of!

It's a perfect ten.

(Ship's horn)

Meanwhile, in Mozambique,

the boy racers have turned leaping into a new and dangerous game.

Playing chicken with a supertanker.

The huge bow wave offers a free ride with almost no effort at all.

They go out of their way to play in this man-made surf.

But all good things must come to an end.

As Spy Turtle discovers, this band of brothers have plenty more ways to entertain themselves.

Naturally, a favourite pastime involves chasing the opposite sex.

But their boisterous arrival is a dangerous time for a baby.

A gang of lusty males can kill a young calf if he gets in their way.

And one male gets perilously close to the baby.

The mother shepherds him away,

while other females create a protective wall with their bodies.

The rest confront the males as the baby vanishes behind a dolphin blockade.

Knowing he's safe, his bodyguards return to face the males.

Their scars are testament to previous fights.

(Chattering)

As always, the spy creatures are right in the thick of it.

They are simply spectators, but as the females get the upper hand,

the spy creatures become a soft target for the males.

They soon run rings round Spy Turtle.

And Nautilus gets some unwelcome attention...

(Heavy thud)

..very unwelcome!

(Chatters)

But Turtle is made of sterner stuff and he keeps filming as the males are sent packing...

..while Nautilus is out for the count.

Calm returns to the female pod and the baby is safe once more.

With Nautilus out of action,

it's time for a new spy creature to take on the feisty males.

Spy Squid is perfectly suited to explore the coral reefs.

Like all the spy creatures, his success relies on the dolphin's innate curiosity.

(Squeaks)

And like a real squid, he creates a jet of water to get around.

Using this jet propulsion, he explores a reef that's a popular spot for the male dolphins.

Why they come here has always been a mystery.

But the squid soon discovers that they use the coral reef as an impromptu health spa.

Favourite coral heads are used like pumice stones, helping to shed off old skin.

They visit the same chosen scrubbing sites time and again.

Incredibly, dolphins replace their outer layer of skin once every three hours.

It's vital for an animal where streamlining is everything.

By rubbing against the coral, they help speed up the process.

It's the ultimate way to exfoliate.

After a good scrub and a scratch, the dolphins move on.

But Spy Squid has attracted the attention of some less friendly reef dwellers.

Potato cod are nearly six feet long and weigh over 100 kilograms.

And they eat squid for breakfast.

Spy Squid is dicing with death.

Time for a sharp exit.

Meanwhile, the male dolphins have found yet more ways of occupying their overactive minds.

(Waves crashing)

Africa's southern coastline is renowned for its huge breakers.

And whenever surf's up, it's the perfect time for the dolphins to catch a wave.

Being so intelligent, dolphins like to keep themselves fully occupied.

Unlike most animals, much of what they do is simply for fun.

Like experienced surfers, the dolphins know that timing is everything.

They turn in perfect synchrony.

Squid finally catches up and goes for the ride of its life.

But even for dolphins, the waves are sometimes just too challenging.

And for the Squid, it's total wipe-out.

Among the nearby female pod, the young dolphin is now over six months old.

He'll keep suckling until he's nearly fully grown and ready to leave his mother.

He's a bundle of energy and just loves to play and leap.

But at this age, lessons are starting to get serious.

One of the first was how to catch fish. Now he must learn to do it on his own.

He must master using his sonar to locate food hidden in the sand.

(Clicking)

He's an attentive student, mirroring his mother's every move.

But mastering his sonar isn't exactly child's play.

A misfire will give the game away and scare off the fish.

(Squeaks)

Missed!

Eventually, he gets the knack - and his much deserved reward.

He will need these skills when, at two years old,

he will finally leave the maternal group to set up life outside.

Back with the spinners, Spy Turtle joins the other spy creatures.

As the pod passes, he's completely surrounded.

A super pod like this can be over half a mile long.

Down below,

Tuna is suffering the consequences of being in the heart of the action.

Dolphins consume a lot of fish... and the result is a lot of waste.

But for dolphins, pooing on your friends is socially acceptable.

It's full of pheromones - giving information about the state and mood of other dolphins,

as well as the food they've just eaten.

It's all too easy to take a direct hit.

This is actually a complement - she really is a dolphin-friendly tuna.

Out of the firing line, Turtle is still having a bit of trouble keeping up.

He valiantly does his best.

But when they really press the accelerator, there is nothing he can do.

Tuna isn't so easily outclassed.

And she soon spies why the spinners are so excited.

Bubbles stream from the spinners' blowholes,

showing that the dolphins are whistling out their names.

(Whistling)

These signature whistles fill the ocean with glistening speech bubbles.

It's a magical sight that has never been filmed before.

But the wonders continue as the reason for their excitement becomes clear.

Another super pod is approaching.

Incredibly, the two groups start to combine.

(Chattering)

The numbers grow and grow until they form the greatest dolphin gathering ever seen.

This is the legendary mega pod, made up of over 3,000 dolphins.

Never have so many dolphins been filmed in one underwater view.

It looks more like a vast fish shoal than a pod of dolphins.

Dolphins can only reach these numbers in the deep ocean

where vast fish shoals can be found.

Here, the ocean bottom lies 3,000 metres down.

At the surface, Spy Turtle has only just managed to catch up.

(Whirring)

Below, the new arrivals start to get to know each other.

And romance blossoms everywhere.

Unlike the bottlenose, they appear to be meeting in peaceful harmony.

(Chattering)

In the mega pod, it seems, free love reigns.

And as Turtle discovers, love indeed is all around.

A pair of Olive Ridley turtles are also caught up in the romantic mood.

The male clasps his mate using special claws on his flippers.

But while he's on board, the female is firmly in the driving seat.

And when she shows an interest in Spy Turtle, there is simply nothing he can do.

Unfortunately for him, she seems to prefer Spy Turtle.

She strokes his face to show her interest.

But Spy Turtle has a job to do, he's here only to observe.

And he leaves them to it.

The natural order is restored once more.

There's always more dolphins to film.

Back in Mozambique, Spy Squid is also on duty.

He soon discovers that the male bottlenose are also in a playful mood.

Pieces of seaweed and other trinkets plucked from the ocean floor

often become treasured possessions.

(Chattering)

The more interesting they are, the better.

And wafting fronds of sargassum seaweed are the most sought after of all.

They delight in gathering and carrying them.

And showing off their catching skills.

But today, these seaweed garlands have another purpose.

The males carry them like floral bouquets towards the females.

The females react as before, confronting the males with a show of strength.

The youngster may now be over a year old but his mother still shepherds him away.

It's better to be safe than sorry.

But something has changed.

The males have come bearing gifts and their plan seems to be working.

A male with a bouquet catches the eye of a young female.

And he shows off his skills.

She seems impressed.

He drops the bouquet...

..and she catches it.

It's now her turn to flirt, using the garland to tempt and tease.

They may now be an item, but they won't spend much time alone.

His mates muscle in and the female is spoilt for choice.

No other mammal uses gifts in this way.

It's another demonstration of their superior intelligence and refined social skills.

The two may have planned to be alone,

but among bottlenose, mating is rarely a private affair.

Even the mother is swept up in the flirtatious mood...

..although she won't be ready to breed until her boy leaves home.

Back in the Pacific Ocean,

Spy Tuna is on her final mission with the spinner dolphins.

She soon discovers another extraordinary example

of a dolphin's cooperation and intelligence.

Super pods like these march on their stomachs.

And, 30 miles from shore, the deep ocean seldom disappoints.

Their long-range sonar has detected something down below -

a shoal of lantern fish ascending from the deep.

By day, these fish normally live 1 ,000 metres down,

so this is a rare sight indeed.

Plans are quickly made and the spinners start by pushing the fish closer to the surface.

As the dolphins hug the outside edge, the fish react as planned by moving upwards as a mass.

More spinners add to the upward pressure.

The huge shoal is gradually squeezed closer together.

The spinners keep up the pressure,

pushing the fish towards the surface and into an ever-tighter mass.

The swirling shoal has nowhere to go.

And now the feeding begins.

The dolphins pick off any stragglers one by one.

It requires hardly any effort at all.

But in the ocean, a feast is rarely kept secret for long.

These are giant mobula rays -

each with a wingspan of over two metres.

They simply open their bucket-sized mouths and scoop up a super-sized meal.

Dozens of fish disappear in a flash.

But this isn't their only trick.

Their huge wings flick like a whip, stunning or killing dozens of fish with every pass.

The following rays will trawl up the victims

and, in turn, their wing beats create even more carnage.

The spinners won't turn down a second course,

especially one handed to them on a plate.

And yet more rays keep coming.

Together the spinners and the rays work the shoal until every stomach is full.

Even so, they hardly dent its numbers.

Lantern fish are the most numerous fish in the deep ocean.

By fishing so far from land, the spinners and rays gain a rare and sumptuous meal.

Then, as silently as they arrived, the rays are gone,

leaving the dolphins to their games.

Having eaten all they can, the spinners celebrate as only they know how.

They party way into the night.

Back in Mozambique,

the young male bottlenose is now growing increasingly independent.

He has learnt to succeed as a dolphin by being curious about everything.

And when Spy Clam produces a trail of bubbles, he's instantly captivated.

(Squeaks)

Dolphins test everything with their mouths.

But he soon discovers that bubbles vanish as soon as they are touched.

(Squeaks)

Another young friend can't resist having a go.

Irrepressible curiosity and constant learning all adds to their exceptional intelligence.

It's now time to move on.

There's plenty more fun to be had in the ocean.

Especially as a new stage of life is just beginning for the young bottlenose -

an exciting time of independence.

Next time, find out what happens as he sets off alone...

..step into the world of the orca, the greatest dolphin in the ocean

and take the ride of your life on the back of a real-life spy dolphin...

uncover more mysteries of the dolphins' secret lives

and discover what happens when one of the spy creatures finally pushes his luck too far.