All language subtitles for BBC.Thailand.Earths.Tropical.Paradise.1of3.The.Secrets.of.the.South.720p.HDTV.x264.AAC.MVGroup.org

In the heart of Southeast
Asia is an ancient kingdom...

..with over 3,000km of coastline.

But beyond its golden shores,

there are secret worlds.

Home to mysterious creatures...

..and forest giants...

This is a fast-changing country

where East and West collide.

People and animals must
work together to survive...

..forming unique relationships.

A spiritual land,

full of magic and wonder.

This is Thailand.

Southwest Thailand.

A wild paradise of limestone castes,

golden beaches and dense forests.

Along this rugged coast are
some close-knit families.

A troupe of 30 long-tailed
macaques has made this their home.

This youngster has relied on his
mother for the last six months.

But he's now at an age where
he needs a more varied diet.

Trouble is, this is one of
Thailand's most extreme locations...

..a vertical rock face, 50 metres high.

Up here, good food is scarce.

Bark and leaves provide little energy.

Macaques are the most resourceful
and wide-ranging monkeys on earth

and have learned to take
advantage of every opportunity.

But this one involved
a precarious commute.

It's especially risky for a
mother carrying an infant.

For a young macaque
still learning the ropes,

having a tail longer than
your body gives you the edge.

It can both grip and
act as a counterbalance.

This daily descent is
well worth the effort.

Across Thailand,
there are thousands of Buddhist temples

and families like this get
a surprisingly warm welcome.

Thai Buddhists have a unique
relationship with nature.

For them, every living thing
contributes something to the world

and deserves respect.

This compassionate relationship
is the perfect example

of the spiritual connection so
special in southern Thailand

where humans are not set apart
from nature, but live within it.

There are other welcome benefits for
the macaques who visit this temple.

A chance to cool off and have
some fun in the heat of the day.

Southern Thailand is a natural paradise

for people and animals alike.

Hidden coves and scattered islands

give it a total of 3,000km of coastline.

Its western shores have been carved
and shaped by the Andaman Sea.

Here, astonishing limestone
castes have been created -

towering stacks of
ancient shell and coral.

This one stands 50 metres tall.

Once part of the seabed,

it was thrust up by
extreme geological forces.

The power of the sea and seasonal rains

continue to sculpt this
dramatic landscape.

Every year,
millions of people are drawn here.

Most come to relax.

Others are here for an adrenaline rush.

Ao Nang Tower stands
nearly 100 metres high.

The ultimate challenge
for thrill seekers.

People come from all over the world
to climb these extraordinary cliffs.

But the locals have been
scaling them for centuries.

And it's not thrills they seek.

It's natural treasure.

These men have their sights set on

a cave hundreds of metres
up a vertical cliff face.

Inside, there's a hidden prize,

but reaching it is fraught with danger.

There's no hi-tech climbing gear here.

Just old ropes and local knowledge.

They must also navigate
a treacherous interior...

..a ten-metre drop into total darkness.

This is what they're after.

Tiny, almost translucent birds nests.

They may not look much, but in Asia,

they're a highly sought-after delicacy.

Eating birds nest soup is thought
to boost the immune system,

improve skin complexion
and fight ageing.

It's no wonder one kilogram
of nests is worth over 2,000.

Wild nest collecting has been
going on for over 500 years.

Recently, the safety and sustainability

has been brought into question.

But an unexpected answer was found.

Thousands of loudspeakers
in the town of Pak Phanang

play birdsong at full blast.

Tweeting 24 hours a day,
seven days a week.

What was once a traditional
fishing town is now at the heart

of a brand-new industry -

bird nest farming.

Windows have been sealed up.

The darker inside, the better.

All to accommodate a
very particular resident.

The edible nest swiftlet.

During the breeding season,
the salivary glands of the swifts expand

and produce extra thick saliva.

Layer upon layer over 40 days,

the birds craft it into a cup-like nest.

These new nesting sites
are helping this bird

make a good recovery
after years of decline.

Each day,
as the swiftlets are out feeding,

farmers like Mr Mu check the nests.

He waits until pairs
have bred successfully

and the chicks have fledged

before collecting their precious nests.

The people of Pak
Phanang have a risk-free,

sustainable way to harvest the nests

and the swiftlets have a new
network of nesting sites.

Across southern Thailand,

people and animals are finding
new ways to live together

and that sometimes requires
a bit of ingenuity.

Over 50km off the mainland

lie two of the remotest
groups of Thai islands,

Similan and Surin.

With crystal clear waters

and golden beaches...

..this place might look like paradise,

but dragons roam these shores.

A giant monitor lizard,

two metres long...

..looking for food.

It tastes and smells the air
with its 30-centimetre tongue,

sensing even the
slightest hint of a meal.

Hermit crabs protect themselves
by hiding their soft bodies

in the abandoned shells
of other creatures.

They live up to 30 years,
so as they grow,

they need to upsize their homes.

But there's something of a
housing crisis on this island.

These idyllic hideaways
are a magnet for tourists,

who find it hard to resist
taking the occasional souvenir.

Every time a shell is removed,
a crab loses a potential new home.

So these canny crabs have found
another source of housing.

Each evening, the rangers clear
the beaches, piling up the litter.

And now the crabs do
something extraordinary.

This hermit has found
herself a more modern home...

..in a mackerel tin.

With so few shells around,
it's an ingenious solution.

And she's not alone.

This is a fast-growing trend.

An aluminium fizzy drink
can makes a lightweight home

that's worth fighting for.

Life in the mackerel tin isn't ideal...

..and the local rangers know it.

So they leave seashells
near the rubbish piles

to help the homeless crustaceans.

The crab normally winds its
body into the spiral of a shell.

It's far harder to grip a
straight and slippery can.

There are plenty of options.

It's all about finding a snug fit.

Well, she can be picky if she wants.

Moving house is an important decision.

At last, the perfect home.

It might look like paradise,

but living along this coastline
requires great resourcefulness.

In southern Thailand, long-tailed
macaques are sometimes known as

"Ling Thalay" - sea monkeys.

And it's not hard to see why.

But this isn't just
about having a good time.

Like their temple-visiting cousins,
they've got a clever plan.

They've adapted their lives
to the rhythm of the sea.

And twice a day,
low tide reveals a feast -

nutritious shellfish.

Trouble is, shells are tough to crack.

But ever resourceful, these macaques
have found a smart solution.

They've worked out that rocks
make perfect shellfish hammers.

Although clearly some macaques
are a little smarter than others.

Either way,
low tide provides a seafood bounty.

Stone tool use is a rare
skill among monkeys.

But these macaques can only benefit
from it by being completely in tune

with the cycles of nature...

..something many of Thailand's
human residents aspire to.

The south of the country is rich
in Buddhist temples and shrines.

Sacred places where monks seek to
understand themselves and the world

in which they live.

Buddhist principles place human life
in the context of a series of cycles

like those in the natural world.

For more than 2,000 years,

the full moon has been celebrated
as an embodiment of this idea.

This celebration of the full moon
is embraced by visitors to Thailand,

but their version is
rather more exuberant.

Koh Phangan's famous beach party is
a rite of passage for backpackers

passing through southern Thailand.

Partygoers are bathed
in ultraviolet light

and their fluorescent body paint glows.

But hidden from view,
just below the water's surface,

there's an equally vibrant display.

By shining the same
ultraviolet light underwater,

an unexpected wonder is revealed.

These tropical waters are home
to an abundance of coral reefs.

A protein within them absorbs
the ultraviolet light,

emitting back a whole new spectrum.

These corals are all fluorescing.

First discovered in the 1930s,

scientists are still
debating why this happens.

One theory is that fluorescent proteins

might act as a type of sunblock...

..protecting the coral from
the sun's intense rays.

But it isn't just corals
that glow under ultraviolet.

It's possible that other creatures
are able to see this show, too,

and use it to their advantage.

One reef resident's behaviour
seems to support this theory.

The scorpion fish is an ambush predator

so camouflage is key.

Passing fish need to beware.

Come too close and his cavernous
mouth will suck them up

in a split second.

For this scorpion fish,

red fluorescing algae appears
to be the perfect disguise.

Southern Thailand's secret worlds go
far beyond its dazzling coastline.

In the very centre of the peninsula
is a freshwater lake called

Cheow Lan,
surrounded by great mountains.

Limestone peaks intercept
moisture-laden clouds,

producing much-needed
water for this rainforest.

3,000 square kilometres of it.

It is home to an exceptional
diversity of plants and animals.

For 12 million years, the forest has

echoed to strange and haunting sounds.

The wing beats of a giant.

The great hornbill.

For this male,
it's an important time of year.

Inside this nest hole
is his lifelong partner.

There's a slit just
wide enough for a bill.

But she's sealed in and won't
come out until her chicks fledge

in four months' time.

For now, she's completely reliant
on him to find food for them all.

A long bill makes fruit easier to reach.

It's tossed to the back of the
throat and stored in a pouch.

Remarkably, hornbills can carry

over 250 berries at a time.

Delicately regurgitating one at a time,

he eases his beak
through the narrow hole.

This devoted couple have raised

chicks in this tree for over a decade.

And because they might
live to the age of 40,

they should be back here
for many more years to come.

On the east coast of Southern Thailand,

there is another secret world far from

the tourist trails,
teeming with wildlife.

Flat coastal plains are home
to four expansive lagoons,

covering over 8,000 square kilometres.

In Thailand's largest lake,

local people are finding
unique ways to make a living.

Somjai is a farmer.

He's raising the only large
animals to be found here.

Somewhere amongst this expanse
is his herd of water buffalo.

Although their wild ancestors
are native to Thailand,

these are domesticated buffalo.

Somjai lets them live
a mostly wild life.

But in the evening, he tracks them down.

In the shallowest parts of the lake,
punting is the only option.

The buffalo spend the day feeding
on the rich aquatic plants.

In the 40 degree heat,

a mud bath cools them
off and repels insects.

The buffaloes' splayed hooves stop
them sinking into the soft ground.

But the constant exposure
to water can be damaging.

So he must round them up and steer
them into a dry pen for the night.

For Somjai, this work is about much

more than making a living.

The dry pen not only
protects their feet,

but gives them a chance
to rest for the night.

This free range partnership also has

unexpected benefits for
the wider ecosystem.

Ploughing their way
through the wetlands,

spreading seeds as they go,

the buffalo help important
plants to regenerate.

Carpets of lotus flowers create a
haven for over a million birds...

..making this a wetland
of global importance.

It's the perfect place for specialists,

those with a light step...

..and fast reactions.

This purple swamp hen may look ungainly,

but he's got a secret weapon.

Huge feet to spread his body
weight over the floating foliage.

This helps a lot when
stealth is not your style.

He also has a particular taste in food,

unwittingly helping to
protect his habitat.

Golden apple snails aren't native
to Thailand and can harm natural

habitats when numbers boom.

Luckily, swamp hens love them.

If they can find them.

A secure footing is vital when
you're trying to haul in your catch.

Long toes mean a foot can act as a hand.

Purple swamp hens are perfectly
adapted to this environment,

and in a small way,

these accidental conservationists
are helping to preserve it.

These aren't the only animals

helping to conserve the natural
beauty of Southern Thailand.

This is Kui Buri National Park.

Formerly thick forest,

it was cleared for farmland
and the wildlife forced out.

In the 1990s,

public support for Buddhist-inspired

environmental principles
started to grow.

Respecting the natural world was
not simply a spiritual notion.

It had to become a reality.

In 1999, the government gave
this area back to nature.

These native elephants reclaimed land

and have had a remarkable
impact on the ecosystem.

Asian elephants need to
eat 150kg of food each day.

They eat over 50 different plant types,

spreading seeds far
and wide in their dung,

replanting Kui Buri's forest.

And by pushing through the undergrowth,

they create pathways for smaller
animals like sambar deer.

They also give birds an opportunity
to pick off scattering insects.

Elephants were allowed
to rebuild the ecosystem

and they have done just that,

creating a wild paradise.

Turning this habitat back over to

the animals has restored the balance.

But in other habitats,

sometimes only human
intervention will do.

Although these boards are
being used for a bit of fun,

the Thai people invented them
long before the wake board.

And when used in the traditional way,

they are a vital form of transport,

and the best way to get safely
around a mangrove swamp at low tide.

These men are here on urgent business.

Mangroves once covered much
of Thailand's coastline...

..but since the 1960s,

half have been uprooted to
make way for shrimp farms.

When people began to realise
the devastating impact

of shrimp farming on the landscape,

they started looking more closely
at this vitally important ecosystem.

Decomposing leaves
provide valuable nutrients

which support a rich biodiversity.

Mangroves also act as a barrier
between the land and the sea,

protecting low-lying communities
from storms and coastal flooding.

They produce seeds that are buoyant,

floating away and germinating
in far away places.

As their roots grow outwards,

they trap sediment,

and are one of the few habitats

that can actually
build up the coastline.

Cutting down the trees is now illegal,

and over the last 30 years,

volunteers from all over the south

have been replanting
the mangrove forests.

Little by little, this crucial
habitat is reclaiming the land.

And mud skippers are moving in -

a tangible sign of recovery.

Seeing them here means there
is a healthy supply of food.

And a good tidal flow
creating lots of fresh puddles

to keep their skin wet.

For ecologists,

seeing them living in a new forest

is a sign the ecosystem
is functioning once again.

And this mangrove restoration
has far-reaching effects.

The coral reef owes its clear waters
to the mangroves' natural filtering

of silt and pollutants.

South-east Asia has more coral reef

than any other region of the world.

Lying at the heart of this area,

Thai waters are home to more
than 2,000 types of fish...

..such as the moray eel,

clownfish,

and cuttlefish.

When the reef is in balance,

every individual plays a crucial role.

The crown of thorns starfish grazes
on the fastest-growing coral,

giving the slower-growing
corals a chance to catch up.

Long-spined sea urchins feed on algae,

clearing the way for coral growth.

But the reef is a delicate ecosystem

that can easily be
knocked out of balance.

Pollution and a loss
of natural predators

can cause starfish and
urchin numbers to explode.

Both are covered in venomous spines.

But there is one renowned reef
resident able to take them on.

The titan triggerfish.

They've got a fearsome reputation...

..aggressively defending
their patch of reef.

A sea urchin's spines are no

protection against teeth like these.

Although the crown of thorns
is well protected on top,

it has a soft underside.

Titan triggerfish play an important role

in keeping numbers at healthy levels.

And with this much food around,

it's a great place to start a family.

This couple have a little
bundle of eggs to care for.

While the female blows water
over the eggs to oxygenate them,

the male is on guard patrol.

This sort of parental
care might be surprising,

but it's vitally important they protect

the next generation of reef helpers.

All the creatures here play their part.

And this has a direct
influence on the open ocean.

When the coral and other
reef animals spawn,

it helps to feed the plankton.

Some of this is swept up by
large filter feeding animals...

..like the manta ray...

..and whale shark.

The rest can drift far away,

forming a floating food supply.

This not only supports
life under the sea,

but also above it.

Fish is the most important source
of protein in Southern Thailand.

Almost two million Thai people keep

the country supplied with this staple.

In this village on the
east coast of Thailand,

Bang, his wife Patima,

and their son Thongchai
rely on a good daily catch.

Early every morning,
they head out to sea.

Before they cast their nets,

there's a sign from nature
they always hope to see...

..something that helps guide them
to the biggest shoals of fish.

This is the Indo-Pacific
humpback dolphin,

a species found in coastal
waters from India to Australia.

It's sometimes called the pink dolphin.

Grey in their juvenile years,

they slowly lose this
colour in blotches,

turning bright pink
when they fully mature.

These unusual-looking dolphins

scour the coastline in search of the

small fish that feed on plankton.

Anchovies are a favourite for
dolphin and fishermen alike.

And today it's a good haul.

There's one more thing they want
to do before heading back to shore.

Across their range,

pink dolphins often forge special
relationships with people.

Southern Thailand is a natural paradise

where people and nature
are deeply connected.

For many Thai people,

their existence is no more
important than those creatures

with whom they share their world.

Habitat to habitat,

surprising connections
and partnerships run deep.

This is a place that draws
people from all over the world

to enjoy its beauty.

It's a wild wonderland

full of unexpected surprises.

The coral reefs of southern
Thailand are world-renowned.

But there's an animal that lives on

the reef that strikes fear
in all who enter the water.

It's definitely the fish
that everyone is scared of.

Like, we have some sharks, no problem.

I don't want to get on
the wrong side of them.

This woman got bitten or rammed
on her head or something.

And there was just blood
pouring down her head.

The titan triggerfish.

It may be only 60 centimetres long,

but its huge teeth are built to bite

through coral and shell.

During the breeding season,
they're particularly aggressive

when caring for their eggs.

And this is what the BBC
crew were here to film.

Producer Lara Bickerton has just
one week to get what she needs.

Seeing a triggerfish at all
would be a start on this shoot.

But cameramen Johnny Rogers and
Simon Enderby are highly skilled

underwater cinematographers.

The waters surrounding Thailand are
famous for their incredible clarity.

But not today.

No triggers. No titans.

No titans. Visibility about
no more than five metres.

Apparently the visibility is better
on the other side of the island,

so shall we go and give that a go?

Yeah.

It's a good plan,
but the crew don't get far.

We're just on our way to another
dive site and found out our boat's

broken down. The ironic result is
the boat that is now towing us is

actually towing us faster
than what this boat

was doing under its own power.

At last Simon gets a second dive in.

Got it?

Although the visibility is still poor,

he captures the odd glimpse of a titan.

They are certainly around.

They're there,
but we just can't see them.

Visibility is too bad.

The crew are told
normal weather patterns

are running three weeks late,

and that could be what's
reducing the visibility.

Things only get worse.

Lara is increasingly concerned.

High winds, heavy rain and rough seas.

The team need their luck to change.

Three days later, the storm passes.

The crew hope the water
visibility has improved, too.

The challenge now is not
finding more triggerfish,

but filming a complete
behavioural sequence.

So the crew focus their attention at
a site where the triggerfish's prey,

the crown of thorns starfish,
is most abundant.

It's a place that marine biologist
Spencer Arnold knows well.

Sometimes starfish numbers can
explode and damage the reef.

So Spencer and the volunteers
from New Heaven Dive School

work hard to remove them.

But there are still plenty
left for the triggerfish.

The titan triggerfish will eat
a crown of thorns sea star.

So obviously very,

very important keystone species on
the island of Koh Tao in terms of

controlling these, these pest species.

The challenge for the crew now is
finding and filming the triggerfish.

With so little time left,

Lara decides to form a tag team,
with both Johnny and Simon working

back-to-back,
maximising their time underwater.

Johnny Rogers is also using
a re-breather diving system,

allowing him to spend over two
hours at a time underwater.

And as soon as Simon comes out,

Johnny gets in.

This allows them eight hours a
day of uninterrupted filming.

With the visibility much better,
the team make progress.

Johnny captures footage of a triggerfish

attacking the soft underside
of a crown of thorns starfish.

It's a great start to the sequence.

We got her on a crown of thorns.

- Did you?
- Yeah. - Awesome. - Great news.

And Johnny's seen a triggerfish.

Well, I've seen one before,
but not on this trip.

It's only taken four days.

The team are soon back underwater,

making the most of the
time they have left.

And Johnny gets a remarkable bit
of behaviour no one expected.

The triggerfish bites each
individual spine off the sea urchin

before devouring the whole thing.

Finally we're actually
getting somewhere.

Simon captures the
final bit of the puzzle.

It's when the titans are guarding

their nests they get most aggressive.

But this couple are
surprisingly chilled,

letting Simon get an intimate view
of the female aerating her eggs.

Well, patience finally paid off.

That's the closest I've
ever come to a nesting

titan triggerfish in my entire life.

Male and female. Male, we found the
male first, defending his territory.

Thought, OK. Actually swam over
the female looking at the male,

didn't notice that. I went, "Oh, hello."

So I was basically this much from her,
puffing away on her eggs.

Sunshine, blue water,

target animals.

Amazing, amazing news.

I am so chuffed at that.

Today has paid off.

The team finally had the
conclusion they needed.

And along the way
learned that if you catch

this notorious fish on a good day,
they're remarkably easy-going.

Next time,
we head to Thailand's bustling capital.

Here, spirituality can be found
in human and animal relationships.

Both likely and unlikely.

This is the very heart of Thailand.

Home to mysterious giants
and striking beauty.