All language subtitles for 02A71EC8AE1D96372A8FF1AC2469964A_eng

Ours is truly a blue planet.

Water covers most of the world's surface.

Here, we are the outsiders.

But under the waves, one group thrives.

Fish.

Fish are masters of the waters.

And sailfish are the fastest of them all.

Their speed makes them one of the ocean's
most fearsome predators.

Off the coast of Mexico, 30 sailfish have
surrounded a ball of sardines.

To catch their prey requires more than
speed alone.

But they are not alone.

In the tightest turns, fins maintain
stability.

Their sickle-shaped tail
powers them forwards, and that

extraordinary dorsal fin
helps intimidate their prey.

To the naked eye, the action is too fast.

Slowed, their challenge becomes clear.

Just picking a target is hard enough.

Knocking it off balance separates it from
the shoal.

This requires extraordinary skill.

Not every attempt is successful.

But as more sailfish join in, when one
misses, another takes its place.

The shoal of sardines is methodically
wiped out.

It's not easy.

Sailfish are top predators.

Very little threatens them.

But for the majority of fish, this is not
the case.

For most fish, the open ocean is extremely
dangerous.

And some go to extraordinary lengths just
to survive.

Flying fish.

Free of the water, they soar on elongated
fins, leaving their predators far behind.

A flight of fish.

Escaping predators is not the only test
facing the flying fish.

They must also protect their development.

Developing young.

These flying fish are searching for the
one thing that will make this possible.

In such a vast ocean, it's not easy.

They're in luck.

A palm frond.

It's a tiny island, adrift in a huge
ocean.

And, like an island, it offers shelter not
for the flying fish, but for their eggs.

The females lay eggs on the raft,
where the males fertilize them.

The first fish spawn, and this triggers
the others to start.

Soon, thousands join the melee.

They're ready to lay their eggs.

Innumerable strands of eggs are laid.

The raft starts to tilt under their
weight.

The best place to lay eggs is right inside
the frond.

For some, the attempt proves fatal,
and living fish become entombed.

The raft starts to sink under the weight
of so many eggs.

But this is far from a disaster.

Sinking away from the surface actually
improves the eggs' chances of survival.

In just a few days, having been safely
hidden in the depths, they'll hatch out.

Other fish protect their offspring in
different ways.

Some go to far greater lengths to care for
them.

The shallow waters of southern Australia
are home to many strange creatures.

It's a fairytale world of seahorses...

stargazers...

and stingrays.

But none compare with the beauty of the
weedy sea dragon.

The dragon's tiny fins beat frantically to
prevent the current from sweeping it away.

It's the beginning of spring.

The season when sea dragons begin their
courtship.

And in the evening light, they start to
dance.

In a graceful duet, each partner mirrors
the actions of the other.

Darkness will soon
draw a veil over the

pair, but they will
dance on into the night.

Two months later, and the result of their
courtship is revealed.

It's the male.

And he's the one that's
carrying the eggs, with

rows and rows of them
embedded in his tail.

That night, the female transferred her
eggs to him.

Since then, the male alone has cared for
them.

By carrying them with him, he's kept them
safe.

And now, it's time for his efforts.

To be rewarded.

The eggs are ready to hatch.

In the calm of a summer
morning, a baby sea

dragon, with yolk sacs
still attached, is born.

The weed bed shelters older dragons that
are already able to feed themselves.

Although these dragons
were well cared for by their

father, now they must find
their own way in the world.

There are fish, however,
which provide their

young with a safe
refuge for far longer.

The southwestern Pacific.

A convict fish.

And it's something of a marine architect.

Underground, it has created a labyrinth of
tunnels.

This adult never ventures out of its
burrow.

What it eats is a mystery.

But it doesn't live here alone.

At another entrance, faces peer out.

Juvenile convict fish.

Unlike their parent, the youngsters are
not tied to the burrow.

And as they start to emerge, a trickle
becomes a flood of fish.

There are thousands of them.

And they all help with the chores.

Many hands make light work.

The young fish swarm together,
thousands of mouths gulping plankton.

What the adults eat must somehow involve
these youngsters.

Whether the young feed
their parents by regurgitating

food or through some other
mechanism, we just don't know.

Whatever the answer, the
youngsters provide their parents

with a meal and, in return,
get a roof over their heads.

Producing young is just one challenge.

Finding food and somewhere to live are
further trials fish must face.

The Californian coast.

A wide range of species live here.

But all this life means competition for
living space is intense.

Old shells are highly prized.

And this one is occupied by a sarcastic
fringehead.

These fish are exceptionally quarrelsome.

They have to be to defend their living
space.

An octopus.

Inadvertently, it's wandered
into the fringehead's

territory and that
can't be tolerated.

The octopus's impressive jab holds the
fringehead at bay.

There is more to this behaviour than being
bad-tempered.

The fringehead needs to
defend its patch if it is to

get enough to eat and the
octopus was competition.

Crabs are not the easiest of mouthfuls.

They can't be eaten.

Because of the shortage of living space,
there are constant boundary disputes.

Especially with other fringeheads.

And this one has got too close.

Despite the most extravagant threats,
neither is prepared to back down.

Success.

And it's quick to get back to its shell.

A fringehead can never drop its guard.

There's too much competition.

Some fish have moved to places where they
have fewer rivals.

A mudskipper.

A fish that spends most of its life out of
the sea.

It can walk on land and breathe air.

Its life is very different from that of
most fish.

A fish out of water?

Maybe.

But they thrive here in Japan.

So what's made this upheaval worthwhile?

The answer lies in the mud.

As the tide retreats, it exposes mudflats.

Sunlight hits the rich silt and tiny
plants and animals flourish there.

All food for a mudskipper.

But life on land is not without problems.

It's hard work to find a mate.

Jumping high above the mud will get you
noticed.

Jumping high above
the mud In the heads, the

mudskippers keep a
lookout for both friend and foe.

And males fight those who intrude on their
territory.

They must also take care not to dry out in
the sun.

Rolling in the ooze keeps the skin cool
and moist.

For this smaller species, a better option
is to retreat underground.

So he digs himself a tunnel down into the
mud.

His heap of spoil is an indication of the
extent of his excavations.

With the tide flooding the tunnel twice a
day, maintenance is a real burden.

The tunnel is more than a refuge from the
sun.

It serves another very important purpose.

The tunnel is actually U-shaped,
and at the far end is a sealed chamber,

the walls of which are lined with eggs.

The eggs are kept in air, as it's richer
in oxygen than the water.

The problem is the air that's trapped here
won't last for long.

So the male travels to the open end of the
tunnel, to gulp fresh air.

Back he goes down his tunnel, where he
releases it into the egg chamber,

replenishing the oxygen on which the eggs
depend.

He will repeat this hundreds and hundreds
of times until his young hatch.

This lifestyle is very
demanding, yet the

mudskipper has found a
way around every problem.

He's thoroughly trained to manage the
water, The harsh challenges of life in the

ocean have encouraged other fish to leave
the sea, not for land, but for fresh water.

Hawaii is the remotest island chain on the
planet.

These pools look the
perfect place for a fish to live,

secluded and free from
competition and predators.

contain fish, for one very considerable
reason.

Surely no fish could swim up this.

But one fish comes from the ocean intent
on colonizing these streams.

It's a tiny goby, and it's a rock climber.

With pelvic fins fused into a
disc, which acts like a sucker,

all the goby needs is a film
of water to climb through.

The pioneer is soon followed by many
others, possibly following its scent trail.

They clamber on, ever upwards,
against the flow.

Drops of water fall like bombs.

False leads waste crucial energy.

Some must rest.

Some must rest.

For others, the effort is just too much.

Many die in their attempt to reach the
top.

Against all the odds, a few heroic
individuals do make it to the top.

They find themselves in a near-perfect
fish.

A fish habitat.

Where the gobies can feed and grow and
breed in peace.

In time, their own young
will be swept downstream and

out to sea, and the cycle
will begin all over again.

Fresh water presents particular challenges
for fish.

Nutrients can be in very
short supply in spring water, so

here, fish must take every
chance they can to find food.

The rain that falls on these Kenyan hills
percolates through the rocks.

Finally, emerging as crystal clear pools.

Pools that are home to fish, including
barbel.

The fish share these waters with all sorts
of creatures.

Including hippopotamus.

These giant vegetarians are no threat to
the fish.

In fact, they're key to their survival
here.

After a night of grazing
on land, these hippos return

to spend the daylight
hours in the cooling waters.

THE HIPPO It's time to meet them.

Soon, each hippo is trailed by a shoal of
fish, waiting for their breakfast.

Hippo droppings.

But it's not just the hippos' dung the
fish are interested in.

When the hippos reach one particular spot
in the pool, they stand still and wait.

And the fish start to clean them.

And the fish start to clean them.

Removing ticks, parasites and other tasty
morsels.

To the fish, the hippos are a mobile
cafeteria.

The hippos seem to be enjoying the
sensation.

The only thing that interrupts the
feast...

is the need to take an occasional breath.

Cleaning the hippo's skin was just the
hors d'oeuvre.

Now, it's time for the main course.

So, the hippos are so busy,
In addition to providing skin

care, the fish look after
the hippos' dental hygiene.

It's an arrangement that suits both
parties.

But perhaps it's the fish that are the
overall winners.

For thanks to the hippos, they are able to
feed on the abundant vegetation that would

otherwise be beyond their reach,
growing around their pool on land.

Providing a cleaning service is clearly a
good way of getting a meal.

And there is cleaning to be done in the
sea as well.

The life of this wrasse is centered on
removing parasites from other reef fish.

Including predatory jacks.

Normally, they would snap up such a little
fish, but this is an established

relationship, and both sides know the
rules.

With so many jacks
and only a few wrasse in

attendance, not all the
jacks are going to get cleaned.

But all this life attracts other
predators.

Silvertip sharks.

The reef provides shelter for the smaller
fish, but the jacks...

remain exposed.

Yet this may be a chance for the jacks to
solve their cleaning problem.

They've spotted an opportunity.

Sharks have skin like sandpaper.

And bumping into the
sharks' flanks helps the

jacks to rid themselves
of parasites and dead skin.

Perhaps the jacks find this a more
effective alternative to the cleaner fish.

And soon, swarms of jacks pursue the
sharks.

All itching to have a scratch.

Unsurprisingly, all this attention bothers
the sharks.

And they head back to the blue water.

Leaving the residents of the reef to
resume life as normal.

Coral reefs are the richest habitats on
Earth.

It's not surprising that with so many
different kinds of animals living so

closely together, some extraordinary
relationships have evolved.

A clownfish, a small and defenceless
resident of the reef.

It seems to have played a role.

They've picked a tough place to live,
amongst the tentacles of a sea anemone.

Each tentacle is armed with paralyzing
stings that can kill a fish.

Yet the clownfish are totally immune.

For this pair, the anemone is like a
castle.

So long as they stay surrounded by the
tentacles, they're safe.

And so this is where they choose to lay
their eggs.

After carefully selecting the site,
work begins on preparing the surface.

Both fish share in the
labor, though it's the

larger female who
decides when all is ready.

Lines and lines of tiny eggs are stuck to
the rock and then fertilized.

They're ready to go.

When they're laid so close to the anemone,
they will be safe.

And for the next seven days, they'll
receive constant care.

Much of which is provided by the male.

His seemingly obsessive concern for the
eggs is for good reason.

His position in the anemone is far from
secure.

The female watches his every move.

She's in charge here, and if his efforts
don't match up to her standards,

she'll get rid of him.

In line to take over are a host of
immature clownfish.

Each waiting to move up the hierarchy.

For the male, the best way to
get them out of the anemone is to

stay in the female's favor, it's
by lavishing care on the eggs.

So he focuses all his efforts on keeping
them clean and healthy.

The eggs grow rapidly, and soon their tiny
beating hearts are visible.

It seems he's done a good job.

Clownfish can hide away within an anemone.

But most fish don't have this option.

For some, the only way of avoiding danger
is by hiding amongst their own kind.

In shoals.

Packed close together, no one anchovy
stands out.

By sensing and reacting
to the movements of their

immediate neighbors,
thousands can move as one.

And that's the way to do it.

For a predator, picking out an individual
becomes nearly impossible.

For a predator, picking out an individual
becomes nearly impossible.

The shoal's unity is its strength.

Yet each fish is acting from selfish
motives.

Moving together, the fish confuse the sea
lions so much that they leave to look

elsewhere for a smaller, less tricky
target.

The sheer size of the shoal defeated the
sea lions.

But there are fish that can overcome such
strategies.

Off the coast of South
Africa, this huge shoal of

sardines is shadowed
by a ragged-toothed shark.

Other sharks join the menacing escort.

The shoal has been driven into the
shallows by a cold ocean current.

And this gives the sharks an opportunity.

Hundreds have moved into position.

Sharks have a special sense.

They can detect the electrical signals
their prey gives off when it moves.

It's a sixth sense that can give them an
edge.

But with hundreds of thousands
of fish crammed into the

shallows, the sharks need only
rely on their speed and agility.

As the first shark starts to hunt in
earnest, a feeding frenzy breaks out.

The shoal's defenses are weakened.

There isn't enough space to maneuver.

SHARKS FLY AWAY And the sharks.

Can forge themselves.

SHARKS FLY AWAY SHARKS FLY AWAY SHARKS FLY
AWAY SHARKS FLY AWAY Despite the

casualties, the shoal is so vast that the
sharks have little effect on its size.

Fish not only come together in great
shoals for defense, but at other critical

times in their lives, when they're ready
to spawn.

These events only occur for a few days
each year.

SHARKS FLY AWAY Snapper are normally
solitary, but they've traveled here from

hundreds of miles away to gather off the
coast of Belize.

SHARKS FLY AWAY
Along this one reef, kubera,

dog and mutton snapper
form huge shoals.

SHARKS FLY AWAY

Sixty meters down, there is an eerie
coolness to the scene.

SHARKS FLY AWAY But things are about to
hot up.

SHARKS FLY AWAY It's the evening of the
full moon.

The tides are just right.

SHARKS FLY AWAY A great column of fish
leaves the bottom.

SHARKS FLY AWAY
As they rise through the

water, small groups
break free of the shoal.

SHARKS FLY AWAY

Each burst is led by a female,
with the males racing behind.

SHARKS FLY AWAY SHARKS
FLY AWAY SHARKS FLY AWAY As

she lays her eggs, they
add their sperm to the mix.

SHARKS FLY AWAY By synchronizing the time
when they gather together, the maximum

numbers of fish can join in this mass
spawning.

SHARKS FLY AWAY Millions of fertilized eggs
are released, cast into the ocean currents.

SHARKS FLY AWAY And straight into a
dangerous world.

SHARKS FLY AWAY

SHARKS FLY AWAY Whale sharks, the largest
fish on Earth.

SHARKS

FLY AWAY Each shark might weigh ten tons,
yet they feed on the tiniest creatures,

including snapper eggs.

SHARKS FLY AWAY

Life is being created, sustained and
destroyed simultaneously in one huge event.

The struggle for life, encapsulated into a
single moment.

SHARKS FLY AWAY The oceans
are perilous places to live, yet

fish have developed the most
extraordinary means for survival.

SHARKS FLY AWAY Their astounding
diversity, the product of millions of

years of evolution, has enabled them to
triumph.

SHARKS FLY AWAY Dominating.

SHARKS FLY AWAY The one habitat that we
have, so far, failed to make our own.

SHARKS FLY AWAY

SHARKS FLY AWAY Filming underwater raised
all sorts of problems for the life team.

SHARKS FLY AWAY Not least of which was
that they were only able to experience the

underwater world for as long as the air on
their backs or in their lungs held out.

SHARKS FLY AWAY But over three years,
the team were lucky enough to capture on

film some extraordinary moments in the
lives of fish.

SHARKS FLY AWAY The
waters off the Yucatan Peninsula

in Mexico are a rich
hunting ground for sailfish.

SHARKS FLY AWAY

Cameraman Rick Rosenthal has teamed up
with sport fishing captain Anthony

Mendillo to try and film the hunting
behavior of these amazing animals.

It's fish!

SHARKS FLY AWAY I'm out.

Feeding birds lead them to the sailfish.

Right here.

Right here.

Getting to the bait
balls and into the water

quickly is key before
the feast is consumed.

SHARKS FLY AWAY Get ready!

If they're gonna eat it, we're gonna screw
them.

Everybody hang on!

Let's go swimming now, Dan!

Come on, get in there.

It's all very well telling Rick to hurry.

SHARKS FLY AWAY But these fish are capable
of swimming at over 60 miles an hour.

Just keeping up with them is hard enough.

Getting right in amongst
the action is vital,

but Rick has to try to
avoid becoming part of it.

Bills nearly one metre long, scything
through the water at breakneck speed,

are guaranteed to get the heart racing.

But Rick holds his
nerve, as the sailfish pick

off sardine after sardine,
right in front of him.

Almost as soon as it started, it was all
over.

I had a wild sea show out there today.

Really wild.

Must have been 50 sailfish, if there
was...

Or 49.

But very aggressive fish, very hungry.

Everybody on the move.

And I had to just keep kicking and kicking
and kicking.

Kicking and kicking
and kicking and kicking

and kicking and kicking
and keeping the action.

But after a while, the sardine patch was
eaten up to just a little sliver.

And then it was over.

Nearly 2,000 miles away, on
the other side of the Caribbean,

another crew is taking a
slightly different approach.

They are trying to film flying fish.

The team sets out at dawn on the
Hogsnapper, a commercial fishing boat.

Conditions are in stark contrast to the
gleaming sport fishing boat in Mexico.

It's dark.

He's ready for action.

Look.

They are hoping to use the
local fishermen's expertise

to put them in the right
place at the right time.

Yeah, roger that.

Yeah, roger that.

You catching there's food.

You catching dinner, lunch and breakfast
there now.

Roger.

It's not a big boat, and the crew's
bedroom has now become the kitchen.

We are having fried bacon and fried egg
this morning.

Fried bacon and fried eggs.

I'm the trainee chef, so I don't get to
wear the white wellies.

Rather than racing around the ocean
chasing the action, the flying fish team

have to sit it out and wait for the fish
to come to them.

Flying fish will spawn onto debris in the
water, and the team tie onto a floating

palm frond to try and make sure they're
close by in case the action begins.

And sure enough, they don't have long to
wait.

Thousands of fish have massed below the
surface, all intent on reaching the frond.

And the frond is not the only thing that
they're trying to lay their eggs on.

The weight of the eggs
sinks the palm frond and puts

an end to the spawning
and to the crew's filming.

At moments like that, we do the job for
everything was right.

The light was right, blue water, the four
tonnes of flying fish all going mental.

Thanks, Barry.

You're welcome.

But now, the fish's attention has turned
to something bigger.

They're spawning directly onto the boat.

Barry is worried as he drags up a huge
sheet of eggs.

I'm gonna bring it in the boat and check
it out.

I cleaned this off like five minutes ago,
right?

Right now, the problem is there are too
many flying fish around us.

If we go through the
night with the lights on and

stuff, more and more
and more will keep coming.

What they're doing here is they're
actually laying on the boat now.

So the boat has become their object,
and that is not good.

So basically, you're
worried that if we just

stay on this drift, we're
gonna sink the boat.

Five hours from now, that will be 3,000
pounds in the back here.

They will sink the boat.

OK, so we're gonna leave it there.

Yeah, we can't stay here.

Just five minutes of spawning has produced
this.

The team have no option but to move on.

The next day, the search for flying fish
begins all over again.

This time, the team want to film the fish
doing what they're famous for.

We've got some lovely
shots of them spawning, but

now the really hard bit
of trying to get them flying.

It's gonna be a good challenge.

The fish are around, but they're all too
far off to film.

The action is impressive this morning.

Unpredictable, but impressive,
but it's distant.

You know, it's not... It's not
happening next to the boat today.

They're either being chased off by
something or they're just not interested.

Look, look, look!

Ah, it's alive!

Aye, aye, aye.

The next day, the crew decides to try a
different approach.

All right, let's go!

Now they're just where they need to be, but
it puts them directly in the firing line.

There they are.

I guess that's why.

Despite being bombarded, their strategy is
paying off.

That was amazing.

We spent a long time in that wee boat
today.

Thanks.

But the last two hours were just off the
scale.

We were just getting shot after shot.

We need... Can't wait to watch it in the
big monitor.

That felt really good.

And Doug is right.

It worked.

Flying fish taking to the air and flying.

Slowed down 40 times.

By working with people more used to
catching fish than filming them,

the life team have
been able to gain a

unique insight into
the hidden world of fish.