All language subtitles for BBC.Natural.World.S28E04.Crocodile.Blues.400p.x265.i95HEVC

The gharial is the world's
oldest crocodilian.

It evolved before the dinosaurs

and at the peak of its range,

it thrived in rivers
from Spain to Japan.

At 20 feet long
and a tonne in weight,

it is the ultimate
fish-eating crocodile,

and one of evolution's
most successful species.

BABY GHARIALS SQUEAK

The gharial's continued
existence on the planet

is owed in part to one man -
Romulus Whitaker.

In the 1970s, Rom and his colleagues

brought the gharial back
from the very edge of extinction,

and they have spent
the past 30 years fighting

to re-establish this crocodile and
protect its ever-dwindling habitat.

They were making slow,
but steady progress,

until last winter, when a mysterious
and unprecedented mass die-off

brought this giant reptile
to its knees.

Is Rom about to witness

the first extinction of
a crocodilian in human history?

Or can he and his team
save this mighty creature

from this current crisis?

This is the story
of a crocodile which,

after 150 million
years of existence,

has been reduced
to less than 200 breeding animals.

HE PLAYS BLUES

I can remember the time
I saw my first live gharial.

The first time I ever picked one up.

I think my sense of amazement for
this creature just hasn't changed,

hasn't diminished a bit.

It is just a too much animal.

GHARIAL GROWLS

As a child,
Rom moved to India with his family.

In this wildlife wonderland,

he developed a passion
for all things reptilian.

Enthralled by snakes
and captivated by crocodiles,

he made them his life's work,
and 60 years on,

he is a living legend in the worlds
of herpetology and conservation.

But the animal that has cast
the greatest spell over him

is India's iconic crocodile,

the gharial.

Evolution has tuned this thing

to be the most
efficient fish catcher,

the best river crocodile
the universe has ever produced.

The gharial is perfectly
adapted to its aquatic habitat.

Powered by its muscular tail,

its webbed feet and natural goggles
make it a swimming machine.

It's able to control
its specific gravity

by shifting
its internal organs,

rising and falling at will.

And its slender snout
with razor-sharp teeth

is the ultimate
fish-catching tool.

But the gharial's
extreme specialisations

make it uniquely vulnerable.

The gharial is just so finely tuned,

and so closely linked to its river
habitat, that if anything goes wrong,

the gharial would be
like a fish out of water.

When Rom conducted India's
first croc surveys in the 1970s,

he found that there were
less than ten adult males

surviving in the wild.

With habitat conservation
and a restocking programme,

by 2006, total population numbers
had increased to over 1,000.

But in December 2007,

the recovering gharial
were dealt a devastating blow.

OK, lots means how many
gharial are dead?

No, there's something very,
very serious going on here.

I'll get up there as soon as I can.

This has gotta happen now,
it's very, very urgent.

The Chambal River Sanctuary
in northern India

is home to nearly half of the
world's population of wild gharial.

But as Rom had learnt,
10% of this vital population

has died in sudden
and mysterious circumstances.

I'm fearing the worst,

because this is really a case of
all your apples in one basket.

If something is wiping out
the gharial and it's contagious,

or it's something irreversible, then
I don't know where it's gonna end.

And no sooner has Rom arrived than
another dead gharial has washed up,

bringing the death toll to 90.

It's a devastating scene.

But Rom's emotions
must be put on hold,

as Rom the scientist takes over.

This is basically...an adult female.

In a way the most important
segment or sector of the population

is the females, who lay the eggs
and populate the river, so...

We're gonna try to learn
as much as we can from this loss.

News of the disaster has
rippled across the world.

A major species is on the brink.

Emergency response teams have
been dispatched to the Chambal,

and Rom has joined a group of
Indian and international vets.

They set to work with an impromptu
autopsy on the banks of the river.

The colour of the flesh is normal
and it's very fresh.

The autopsy is vital to discover
what killed this gharial,

and may provide clues as to
what's causing the larger die-off.

This animal has literally just died.

I mean, we're talking about
earlier this morning.

That means it's in a good
state of preservation, you know?

At this stage in the examination

you don't try to interpret
everything you see,

you're just trying to make sure you
don't miss anything in the picture,

so then you can see
if the pieces makes sense,

so you make sure you describe
each piece at this stage.

You don't find something and say,
"This is a sign of that disease".

The vets address each
of the organs in turn.

The lungs show
no obvious signs of damage,

but the team
is particularly interested

in the joints and kidneys,

which show an unusual build-up
of a powdery white substance.

The team have gathered as many clues
as they can from this specimen.

I don't know what anyone else
has learned about this,

but I've learned a heck of a lot,

because the previous animals looked
at were all quite rotten already,

and a lot of the organs had either
dissolved, or were discoloured.

But I think the major thing
that we're gonna learn out of this

is what the veterinary doctors
come up with.

This is really a grim scenario.

My colleagues and I have worked on
rivers like the Chambal since the 70s

and these are animals
so close to our hearts.

I think we're trying to deal with
the situation, the tragedy of it,

probably the same way you
deal with it on the front line

when a war's going on. It's that bad.

This is the time when
all the birds go home.

As the team head home too,

Rom is wondering whether
there are any more clues

as to the cause of the disaster

elsewhere in the area
surrounding the river.

Back in the 1970s, we did some of
the first crocodile surveys

and found that the Chambal, one of
the wildest rivers left in India,

still had some gharial,
and sure enough it turned out

to be ultimately the place where
the release programme was started,

and in 1979, the government formed
the National Chambal Sanctuary

to protect this fantastic
river stretch of over 400 kilometres,

and now it does have the largest
population of gharial in the world.

It is not just conservation laws

that have preserved
the sanctity of this landscape.

These wild Chambal ravines

used to be the hide-out
of really famous bandits,

dacoits called Makhan Singh...

..and Man Singh and the famous
bandit queen, Phoolan Devi.

Their days are over,
but the place is still wild,

it's still a dangerous place.

There are still some
dangerous folks around.

But what it's done
for the Chambal river

is actually protected the place,

because people just were
scared to come here.

That's probably one reason why

the gharial has survived here,
and nowhere else.

Where bandits once prowled, it is
now down to Rom and his colleagues

to protect the gharial
and its river.

And it seems the perils
are now more complicated

than population pressure alone.

The Chambal may feel
like a pristine wilderness,

but somewhere in the river
lurks the menace

that's decimating its most
precious inhabitant.

The next morning finds
the vets hard at work,

carrying out another autopsy,
this time on a baby gharial.

Working in their hotel bathroom,

they are weighing up
three possible causes of death -

poisoning, parasites and infection.

But they need to compare
their samples

with those
from a healthy living gharial.

So Rom and the team
head back to the river.

Helping to co-ordinate the operation

is one of India's leading
environmentalists,

Kartick Satyanarayan.

Take the entire kit,
dog catcher, everything.

So that's the net
they brought last night.

Yeah. This is the one Dibulal got?

Yeah, but we've got a back-up net
here too, a huge one, which Basu got.

OK. And we have a third net,
which came from Agra.

I don't think we're
taking any chances.

If we need something
we'll call for you.

They do say that
too many cooks spoil the soup.

In this case, everyone's essential.

An operation like this,
if it's not well planned,

obviously it's not gonna succeed,

so it's worth all this banter
and backing and forthing

to make sure
we've all got it straight.

...Let's go.

I love it when
someone just says the right word

and everyone starts moving!

Good. Thanks, Kartick! Fantastic.
...And we get in here. OK.

Come on, let's go.

To catch at least
one live healthy gharial

is very important for the vet doctors
because they need to check the blood,

and you can't take blood out of
a dead gharial, the blood congeals.

So we very much need a live gharial.

Although the Chambal River
Sanctuary is 250 miles long,

the affected gharial have
all come from a 25-mile stretch.

It also appears that only
a certain size class of animals

is being affected.

Adding to the mystery is the fact
that other river reptiles,

like the mugger crocodile
and soft-shell turtles,

appear to be in robust health.

And birds that share the gharial's
diet also seem to be unaffected.

We're looking at a fish-eating bird

and they've got the same food chain
as the gharial has,

so if the gharial is being affected

by something in the fish, in the
food chain, why aren't the birds?

But while Rom is busy
mulling over the mystery,

Kartick has got to work.

And in one of the many nets,
he's landed the catch of the day

and brought a smile to Rom's face.

Kartick!

Oh, man, she's gorgeous.

Fantastic, man. This is so good, man.

Oh, she's beautiful. She's beautiful.
Absolutely.

GHARIAL GROWLS

Mmmm! Yeah, I feel the way you do.
She's talking.

Don't worry,
you won't be out for long.

So fortuitous because the doctors are
arriving at the same time,

so we've got all the experts and now
we'll be able to get a blood sample.

This looks like a good place.

'I think that went incredibly well.

'First of all, the odds of us
catching a live gharial

'within a few hours of trying,

'and we got it right within
the size class

'of the animals which
are dying in the Chambal,

'the foreign vets,
they got samples of blood,

'cells from the liver,

'they got a bit of gastric content,
in other words the stomach contents.

'There is a bit of pain when
the needle goes into the skin,

'because it does have nerves, just
like any of us getting an injection,

'but he didn't really struggle.'

The point is we're trying to
find the source of this problem,

and for one gharial to suffer
for a few minutes a bit of pain,

I think is really necessary
at this point

because we're trying to get to
the bottom of the major die-off,

which has never happened
to any crocodilian that we know of.

Scientists and ecologists fear

that we are on the brink
of multiple extinctions,

as ecosystems around
the world collapse.

Could the mysterious
die-off of gharial

be a foreshadowing
of some larger cataclysmic event?

OK, this is a very sacred moment.

We've got to remember

that gharial are able to turn around
almost completely...

And as another of our most
endangered animals

is brought to the brink,
is the world finally ready

to sit up and take notice?

Wow!

Fantastic, eh?

Fantastic.

Ah!

While Rom is waiting for
the vets to report their findings,

he heads back south to Chennai
and the Madras Crocodile Bank.

This is the centre
he established in 1976

for the captive breeding
of India's endangered crocodiles.

Over the years it has bred
thousands of animals

for release into the wild.

It's now an internationally renowned
research centre

and educational facility,

and headquarters for
Rom's conservation work.

Croc Bank is really the base of
all our conservation operations

on crocodilians in India.

Whatever we've learned about
crocodilians, this is the repository.

This is where we start out
on all our fieldwork,

and this is where we end up
when we come home.

Over three decades, Rom has built up
the Croc Bank's gharial population.

It's an insurance policy
against their decline in the wild.

The Chambal die-off has reduced
wild breeding numbers to below 200.

Rom's efforts here are suddenly
key to the survival of the species.

In the 1970s, the Croc Bank
inherited its first four gharial.

There are now 13 adults and these
are the two sexually mature males.

At the start of
the annual breeding cycle,

each attempts to assert
its dominance over the other.

This is the height of the mating
season, and we get to see

some incredible stuff here
in the gharial breeding pit.

This is the time of year

when one adult male tries to outdo
the other one and chase him out.

It can't get out of here,
so sometimes massive fights ensue.

The males might work out
their own pecking order,

but it was up to Rom
to perfect the art of breeding them.

Back in the 70s,
we didn't really have a clue

how to breed them in captivity.

They'd never bred
in captivity before.

What was critical and pretty obvious,
from the beginning,

was that we had to have adult animals

and it took 13 years before
the gharial finally grew his ghara,

on the tip of his snout, and we
realised, OK, now it's the time.

The ghara,
which gives the gharial its name,

is a lump of cartilage which grows
on the snout of mature males,

and plays a key role
in attracting a mate.

Their real method of
attracting the females

is doing something we call
a buzz-snort. It kind of goes like...

prr-rr-rrrp.

It sounds very impolite,
but it seems to be very effective

and it's created by the fact that
the ghara of the male,

sitting on top of its nostrils,

sort of modifies the sound
of its hissing

into this very, very weird, but
effective way of attracting females.

When they finally did start breeding,
it was an amazing day for us.

The first clutch of eggs,
I think it was just 12 eggs,

and virtually
every one of those eggs hatched,

so we knew we were
doing something right.

What Rom and his team achieved
in the 1970s

was vital for
the future of the species.

It was extremely important for us
to breed the gharial in captivity,

at that stage.
It was down to 200 in the wild.

These things were really endangered

so it was critical that we got
them to breed in captivity.

Rom's captive-bred gharials have
been released into the wild

in two locations - on the Chambal,

and at a sanctuary on the
River Girwa called Katernia Ghat.

Rom needs to make sure that
the Chambal's devastating die-off

hasn't taken hold
in this second sanctuary,

so he's travelled to Katernia Ghat
to see for himself.

For Rom, it's like coming home.

This is Katernia Ghat.

We've got 15-20 kilometres
of pristine river.

We've got gharial, we've got mugger,
bird-life...

I'd call it one of the best-kept
secrets in India, really.

The Garden of Eden for one of
my favourite animals, the gharial.

But all the other life here too.

It is totally amazing.

Rom's first task is to travel
the length of the protected area

and carry out a census,

checking on the numbers and health
of the Katernia Ghat's gharial.

'It's just incredible to think what's
going on in the Chambal right now

'and gharial just dying like flies,

'but it's even more important
that a place like Katernia Ghat

'is secure for gharial.'

In 2006 there were some
60 adult gharial

living in
the Katernia Ghat Sanctuary.

Rom's hoping that this population
has at least remained stable.

That's a big gharial.

A preliminary tour
has revealed about 30 gharial

and thankfully these animals
are all in good health.

I would say here is a secure
population, and as a back-up

to the Chambal population, it's now
become more and more important

to make sure that this stays intact.

But Katernia Ghat is minute,
and Rom's "secure population"

has little more than three miles
of ideal habitat in which to live.

You have to look at it
in a global perspective.

You've got probably 25%

of the entire breeding population
of gharial in the entire world

right here,
in a little chunk of habitat,

with no protection below
and no protection above,

so it's very finite
and it's very fragile.

And although these gharial
are free from the mystery die-off,

they are beset on all sides
by other pressures

that may prove to be just as deadly.

Even right in the sanctuary here
there are several villages,

people living here.

This is a very, very packed state,
the state of Uttar Pradesh.

Population pressures are everywhere.

A major threat to the wildlife
at Katernia Ghat is fishing.

Illegal in the sanctuary itself,

it happens right up to its borders
both up and downstream.

Subsistence fishermen and gharial

have long competed
for the same catch,

but today's contract fishermen
and monofilament nets

give people an unfair advantage,

and have an unfortunate
side effect for the gharial.

Downstream outside of the sanctuary,
fishing is a big thing,

and you can see the prey base
for gharial is perfect here,

but the trouble is,

if gharial start
messing around in this,

they get their teeth caught
in it and they get twisted up,

and they might even drown.
This is a big problem.

Luckily, they've sorted it out
inside the sanctuary,

but a gharial doesn't know
where the sanctuary boundaries are,

he comes downstream and gets caught,

it's a very, very bad business
for a gharial.

The threats to Katernia Ghat's
gharial are obvious to Rom,

but the cause of the die-off
elsewhere remains a mystery.

Speculation about infectious
disease and parasites is rife,

but the vets are concentrating on
poisoning through the food chain.

Another Indian animal that might
hold a clue to the gharials' fate

is the vulture.

It shares a diet with
many of India's scavengers.

Where the rest of these scavengers
go from strength to strength,

vultures alone are circling
towards extinction.

The reason why it's such a pleasure
to see these vultures up here

is because in the last ten years
we've lost maybe even more than 90%

of India's vultures, because of
a specific drug called diclofenac.

It's a simple drug given by farmers
to their cattle to reduce pain,

but it's something that attacks
the kidneys of the vulture,

and they die very, very quickly.

Rom suspects something similar may
be causing the mass gharial die-off,

and that whatever is killing
the gharial in the Chambal

may also be specific
to just that species.

But for the moment it seems that
the gharial at Katernia Ghat

are at least safe from the die-off.

And that evening, as Rom returns,

the sanctuary is about to
play host to a remarkable spectacle.

For over 150 million years,
gharial have nested on riverbanks.

But now, in one of
their last strongholds,

they are reduced to nesting
on just one sandbank.

And Rom may be about to witness one
of the last times this ever happens.

It's... It's getting close to sunset.

I'm kinda surprised,
but it looks like

one of the gharial is
starting to climb the bank.

From here, anyway, it looks like
she's full-bellied, full of egg.

She goes up in a jerky way,
it's a very steep bank...

WHISPERS: It's a very steep bank.
I don't wanna disturb her!

And they've got rather weak legs,

strong for swimming,
but weak for climbing up on land,

so she sort of humps her way
up the slope.

But there are other gharial

interested in
this particular sandbank.

Females that
have already nested

are watching proceedings
as closely as Rom.

There's another one coming up,
a larger one.

She looks slimmer.

Looks like she has
already laid her eggs,

and she's a little worried
about that one digging up top.

This is her defensive mood.

It doesn't matter
that it's another gharial,

it's somebody digging.
I don't think she likes it.

There's a very good chance

that one of them will scoop out
the eggs of the previous nester.

There's definitely an urge
to protect their own nest site.

As the camera struggles with the
fading light, more gharial arrive.

The island is getting crowded, and
dominant females begin to compete

for the prime sites
at the top of the sandbank.

Both of the big females are
knocking their beaks together.

They're trying to sort out
who's boss here.

This is really...
I've never seen this before,

but it's obvious that the females
are defending their nest site,

even from other females,

so there is some sort of pecking
order, some hierarchy going on.

And this is a tiny sandbank so
it really is just not enough space

for all these animals, which is one
obvious reason why this is happening.

But the gharial aren't just
competing with each other

for the prime nesting sites,

they also need to see off
the threat of a mugger crocodile,

who is equally interested
in the high sandbank.

The dominant females are distracted,

leaving an opportunity
at the other end of the island.

The smaller one is now on top.

She's starting to
scrape sand with her legs.

I can actually see,
even without the binocs,

sand flying through the air.

The gharial uses its powerful
rear legs and webbed feet

to excavate a nest pit
as deep as its legs are long.

Yeah, she's starting to
dig down inside.

Now you start seeing different
colour sand coming out.

It was dry sand at first.

That dark stuff is the damp sand from
inside so she's making her hole now.

In a scene that has never before
been documented,

the island has become
a busy maternity ward,

as more gharial arrive
and stake their claim

to a precious patch of sand.

They too begin
their timeless nesting ritual,

a process that will last
well into the night.

It's getting very dark. I can
just barely see what's going on.

There's definitely a couple of them
laying though. Good luck to them.

Each gharial will lay up to 50 eggs,

which will incubate
for 70 to 80 days

and hatch just before
the onset of the monsoon.

Next morning,
and the nesting frenzy is over,

leaving the island covered
with the scars

of last night's laying activity.

Amazed by the overcrowding
on the tiny sandbank,

Rom and forest guard Ramrup head
over to count the freshly dug nests.

Using a wire rod
to gently probe the sand,

they find six freshly laid nests,

bringing the total on this island
to a very crowded 24.

It's totally amazing,
and we're probably looking at

maybe even a quarter
of the entire nesting effort

of all of the world's wild gharial
on this little tiny spit of land

that's like, what,
about 40 metres long, 20 metres wide.

It's a tiny place, totally
vulnerable to the monsoon floods,

but the vast majority
of the gharial in the Girwa

are laying their eggs right here,

and we've noticed that some nests,
I mean, some of the nesters,

have dug out other nests and there
are a couple of eggs lying around,

so this is very limited,
and it's very worrisome too,

because what'll happen
when another monsoon comes?

Look at this steep
embankment on this side.

Come over and check this out.

Another steep
embankment on this side.

It's so obvious
the gharial prefer this.

They want to climb up
on to something high.

That really makes sense
in every sense of the word,

because this river does
rise very fast,

and if it rose unseasonably early,

all the eggs would be
submerged and drown.

Rom hopes his worst fears won't be
realised, because this small island

seems to be the only nesting place
for gharial in the entire sanctuary.

It's a precarious scenario
for an already endangered species.

Just a few miles downstream

is a potent vision of why, today,

there are so few
gharial nesting sites.

Where for millions of years they
happily excavated their sandy nests,

India is now extracting
building sand on an epic scale.

Sand mining.
Sand mining in river beds.

I mean, we've got to have sand.

India is growing.
Growing, growing, growing.

Building more houses.
Construction. Everything.

But mining it from a riverbed
is no good.

It's no good for the hydrology and
it's certainly no good for gharial.

Gharial lose their basking spots,
they lose their nesting spots.

Same for turtles.
It's just bad all round.

Although this riverbed
looks like a desert,

it wasn't long ago that
this was prime gharial habitat.

Every river bed in India is
getting drier and drier every year

and this isn't natural.

We're just taking the water
for irrigation,

we're damming it, we're barraging it,
we're canalling it.

We're doing everything to get water
to other places for agriculture.

Needed stuff, but needed - sure -
it's got to be done sensibly, too.

We've got to remember,
we're looking after gharial too, OK?

Back at the Croc Bank,
the most successful enclosure

emulates the steep sandbanks
at Katernia Ghat.

And while Rom has been away,
his prize female Roxanne

has laid her annual clutch of eggs.

This is the spot, right,
where they marked it?

Although this sandbank may
be perfect for Roxanne to nest,

conditions here
in India's deep south

are too hot
for successful incubation.

So the eggs need to be excavated
to ensure that they will hatch.

The reason why he's got
a stick in his hand

is because they are
defensive with their nests.

Nothing like a saltwater crocodile
or a mugger, but...

Nonetheless,
they do have sharp teeth,

and they really don't like
the idea of you stealing their eggs.

It's not just Roxanne
who's upset by Rom's nest raiding.

The dominant male, too, is taking
an unhealthy interest in proceedings

He's a big guy and
a little scarier than the females,

so we just have to
be a little careful here!

Because you know, when you get
concentrated on your work,

you just forget that there's some
toothy little creature behind you.

It's very important to mark
the orientation of each egg,

because if you turn the egg over,
you can actually kill the embryo.

In the present context of the gharial
being critically endangered

and the die-off that's happening
in the Chambal,

captive breeding programmes like
this become more and more important.

And it's really critical that we have
this repository of captive animals,

you know, as a safety measure.

We're hoping like hell that
the gharial doesn't go extinct

in the wild, but nonetheless,
this the back-up,

this is the insurance policy.

46, 47...and one last one.

48.

That's the largest clutch size
we've ever had

at Madras Crocodile Bank
for the gharial.

That's amazing. 48 eggs.

Thanks, Roxanne!

OK, let's get the eggs up,
we're gonna incubate them.

Basically, what we have to do here
is candle the eggs

because that determines whether
the eggs are fertile or not

and Nikhil is an expert at this,
but to be able to do it,

we have to switch the lights off.

OK, let's see what we've got.

This moving dark horizontal line
shows that the egg is viable.

The black spot at the top
of the egg is called banding

and grows as the embryo
continues to develop.

So, the embryo always
attaches itself to the top.

Most of the time. We're calling
that a fertile one, right?

We always used to say, "Treat the
eggs like nitroglycerine."

Easy, easy, don't roll them!

Don't let them explode.

Oh, that's nice.

With his precious clutch
safely under wraps,

Rom has returned to the Chambal,
site of the winter die-off,

to follow up on the mystery.

With the arrival of warmer weather,

the gharial deaths appear
to have stopped,

and through study
of their autopsy samples,

the vets may have reached
a breakthrough.

They have discovered
that the white powder

observed on the gharials' organs
is crystallised uric acid.

Uric acid is not very soluble,

and at a certain level
it reaches saturation.

When it reaches saturation,

it crystallises out. OK.

The amount of uric acid in the blood
is controlled by the kidneys,

and when levels are this high,
it points to kidney failures.

Kidneys are an essential organ
in gharial,

just like they are
in any animal.

When uric acid builds up
in the joints it causes gout,

a debilitating condition,
that in a reptile can be deadly.

An animal with this kind of thing
cannot move its limbs anymore.

So they come along,
go up to the sandbank too fast,

and very often they cannot even
control their swimming,

because they need
their hands and feet for balancing.

Wow. That makes it even sadder
in a way, doesn't it?

It does, yes, yes. Very sad.

Filmed during the die-off,
these images show the death throes

of a gharial crippled
by agonising gout.

The winter's record low temperatures
on the Chambal,

may also have played a part
in this disaster.

The solubility of uric
acid varies by temperature,

so the cold temperature
certainly could play a role

into the manifestation
of disease in this instance.

Death is unavoidable.

The vets believe that the
die-off was caused by gout,

brought on by a combination
of cold weather and kidney failure,

and that the kidney failure
itself was caused by poisoning.

It must be a toxin.
It must be something toxic

in the water or in the fish
or something that they're eating.

They've got a toxin in them somehow.

It seems that Rom's vulture hunch
was right,

and that the Chambal gharial
have been poisoned.

We've all been wondering what's been
going on with the gharial

and the suspect was that it's either
a parasite, a disease, a virus.

In fact, wild speculation
all over the world

about what was going wrong
with the gharial.

But this has really
narrowed it down because,

as Fritz and Brian just explained,

the culprit has got to be
some sort of a toxin.

The vets have discovered
how the gharial died,

but the presence of a toxin
has opened up

a new can of worms for Rom.

What is this toxin?

Is it still lurking in the Chambal?

How did it get there?

The Chambal itself is one of
India's healthiest waterways,

but the river it flows into,
just downstream of the sanctuary,

is far from clean.

The Yamuna may be a sacred river,
but after flowing through

the industrial heartlands
of Delhi and Agra,

it's one of the most polluted
in the world.

And Rom suspects this might be
the source of the lethal toxin

that has devastated the gharial.

We're walking along the banks
of the Chambal.

Actually, it's the end of the
Chambal, because in a few seconds

we're going to be arriving at the
confluence of the Yamuna River

and the Chambal, and I think you'll
be able to see for yourselves -

we've got one of the
dirtiest rivers in India

just here meeting one of the
cleanest rivers in India.

If you

come over to the edge here
and look down,

you suddenly see what
I was talking about.

The Yamuna River sweeps down
from Delhi and Agra

and meets the Chambal River here
and from what I've been told,

the coliforms, in other words
the bacteria and nasty stuff

that causes disease,
has a count of about 14,000 here

and the count
for the Chambal River is 21.

So, my guess is if you took a sip
of this water,

you probably wouldn't last
more than a few minutes,

whereas everyone drinks
the Chambal water.

If another piece in the puzzle of the
gharial die-off is the food chain,

in other words the fish
that the gharial eat,

the obvious answer is that
polluted fish from the Yamuna

are entering the Chambal
and probably moving upstream.

A remarkable factor could be what
the fisherman recently told us,

that there were more than
40 different species of fish

in the Yamuna previously,
and now there's just one.

And that happens to be an exotic,
the African tilapia.

So, something very seriously going
wrong here, ecologically speaking.

The fact that that many species
of fish have disappeared

and are being replaced
by one species,

the only one that can stand this kind
of toxicity and turbidity,

in the mess that we call
the Yamuna River.

As soon as the weather warmed up,

there were no more gharial
dying on the Chambal.

But there's no evidence
that the toxin,

whatever it is, has left
the ecosystem

and there's every good reason
to believe that the die-off

could happen again,
when the cold weather returns.

There is a silver lining
on this, however.

Never before has there been so much
attention focused on the gharial

and how to save it.

The government, the researchers,
the people who have been working

on gharial in the past,
everyone is incredibly motivated.

And now permissions have been given,

and everyone is on board
to try to find the answers.

But until this toxin
and its source can be identified

and removed from the Chambal,

the struggle to save the gharial in
the wild must be fought elsewhere.

And Rom has just received
a package from a colleague,

which suggests that Katernia Ghat
may be just the place.

Last year, our friend and fantastic
naturalist photographer,

Suresh Chaudhary,
was up at Katernia Ghat,

along with the wildlife warden,
Ramesh Pandey,

and they saw an incredible sight
and filmed it.

LOW-PITCH SQUEAKING

The lack of nesting sites
at Katernia Ghat

is so acute that when last year's
16 gharial nests hatched,

500 babies took their first steps
on the same few yards of sand.

All on the very same island where
Rom witnessed this year's laying.

We were up at Katernia Ghat
just two months ago in April.

On that one little island, which had
maybe 16 or 18 nests last year,

there were at least 20,
possibly 25 or more nests,

on that one tiny island.

Can you imagine what we're gonna see?

I mean, it's phenomenal.

It may appear from these scenes

that the gharial species
is in rude health.

But there are only
so many nests here,

because there is nowhere else
suitable for them

on the entire river.

Due to the tiny size
of the sanctuary,

only a handful of these babies,
if any, have survived.

But it's a remarkable sight and the
first time it's ever been filmed,

and Rom wants to congratulate
his Katernia Ghat colleague.

Hello. Suresh?

It is fantastic!

I've never seen so many gharial,

in one place, at one time,
in my entire life.

I couldn't believe it!

But there's a storm
brewing at Katernia Ghat.

So what's happening to the nests?

The news that Rom's just received
is that the south-west monsoon

has arrived at Katernia Ghat.

An annual onslaught
of 80 per cent of India's rainfall,

the monsoon arrives
on the south coast in June

and spreads north across the country
with clockwork predictability.

But this year the rains
have arrived two weeks early,

and the river is in full spate,

rising perilously close to the top
of the gharial nesting island.

As Rom races up from Chennai,

forest guard, Ramrup, is mounting
a rescue mission to the island.

And it's a catastrophic scene.

More than half of the sandbank
has been swept away,

together with hundreds of eggs.

Desperate to save what they can,

the forest guards slap the surface
of the sand like gharial mothers

listening for the calls
of any babies

that may have already hatched.

But there's no response.

With eggs washing away
before their eyes,

they have little choice.

They collect the handful of
surviving nests for captive rearing,

and as the island crumbles
around their feet,

they retreat to solid land.

Within hours the river,
in full monsoon spate,

has sealed the fate
of the sanctuary's

only gharial nesting site.

Meanwhile, Rom has arrived
in Katernia Ghat.

I heard a little earlier,
while I was down in the Croc Bank,

that the river has risen much,
much sooner than it usually does,

and this has put the main
nesting banks into jeopardy.

Rom doesn't realise
quite how dramatic the change is.

My God, man! It's just amazing
how different it is.

The pontoon bridge that was there
in the summer, it's gone.

The sandbanks that we saw over there

with the big gharial basking on 'em,
totally gone.

The river's from one bank
to the other now.

And what he's about to discover is
that the gharials' nesting island

and all their nests have
been obliterated by the flood.

That chunk of blank water over there,

that's where the nesting island was.

That's where all the gharial
laid their eggs this year.

25 nests or more.

And it's gone.
I mean, it's completely gone.

Man!

It's kind of like a ship
going down with all hands lost.

There's not even a trace of it left.

The gharial just did
what they always do,

what they're programmed to do,

and they've done it right
for millions of years.

It's just that it's a very
changed scene now.

You've got deforestation
in the upper Himalayas

and these rivers run much,
much faster than they ever did.

In addition to that, we've got
the spectre of global warming,

which is messing up seasons
and maybe this is a symptom of that.

We've got over a billion
people on the sub-continent

and they may not be
physically entering the sanctuary,

but the pressures from the outside,
the pressures from upriver,

are very visible and have created
this disaster this year.

The disaster on the Girwa
is yet another body-blow

to the survival
of the gharial in the wild.

The future of the Chambal population
is hanging by a thread,

and here in Katernia Ghat,
the wild hatched contribution

from a quarter of the world's
gharial nests will be nil.

Once again this ups the ante for
Rom's eggs at the Croc Bank,

because these eggs, and the few
rescued from the sandbank,

now bear even more responsibility
for the future of the species.

But a captive population means
very little with no wild habitat,

so before he returns
to the Croc Bank,

Rom's investigating where
gharial might nest in the future.

This... Right behind us, right here,
is where the nesting island

was and now all you see is water.

It just totally swept it away.

What we're gonna do now
is try to check out this island

because this is the closest
possible nesting place

for next year's gharial to nest.

Stepping off the boat,
Rom wants to make sure

any lurking wildlife
knows he's coming.

♪ I don't wanna get drafted
I don't wanna go

♪ I don't want nobody to shoot me
In the foxhole

♪ Foxhole. ♪

What about bears?
Do bears live in this?

We're not exactly in the middle
of gharial habitat here.

We're looking in fact at,
what I would consider,

good rhino and elephant habitat.

But the purpose of this somewhat
ridiculous-looking exercise

is to try to find an embankment,
which might be suitable

for next year's gharial nesting.

I was hoping that the land would
start sloping upwards,

but it doesn't seem to be.

It's very level and I am not a rhino.

Actually, we're going down again,
that's not a very good sign.

Getting back down into mud.

It's kinda disappointing.

Um...it doesn't really
look great for the gharial,

because I was hoping the island
would slope up enough,

so we'd be able to find
an embankment.

Even if it wasn't sandy, we could
at least do something with it.

Enough habitat manipulation,
getting rid of some vegetation

and piling up sand might create
ideal gharial nesting habitat.

But you've got to start
with something to begin with,

something higher than the river level

and here we are standing
in almost knee-deep water.

Anyway, it was a try.

As Rom already knows in this
tiny stretch of protected habitat,

suitable sandbanks are
few and far between.

Especially, when the monsoon
floods are this ferocious.

More and more, we're kind of opening
up to the idea that we're creating

a fantastically disastrous climate
change and it's already happening.

The gharial is so tied to what you
could call the rhythms of the planet,

that it is not going
to be able to adjust.

They can't move away,

they've got to nest traditionally
where they've always nested,

come hell or, in this case,
high water.

Rom is realising that
conservation in the future

is going to have to be
much more proactive.

Wouldn't it be great if we could
just leave nature to itself

and everything would be just fine?
Unfortunately, it's not that way,

and more and more, it looks like
we have to make interventions.

We actually have to change habitat
to make it more suitable

for animals like the gharial.

It lost all its nesting habitat
this year.

Now, we've got to make plans
for next year.

And what ten years from now?

I've been involved
in gharial conservation

since the beginning
and I'm not gonna quit now.

It's my top priority.

Without the dedication
of a handful of people like Rom,

the gharial would have
gone extinct long ago.

Faced with this year's disasters,

the species' future is resting
firmly on their shoulders.

Back in Chennai,
Rom is about to find out

if his Croc Bank eggs
can bring any hope.

What happens with these eggs
when they're ready to hatch,

the er...baby starts moving
around inside the egg, and...

..can you hear that?

It's just a very slight sound,

but it's a little grunt
coming from inside the egg.

The gharial actually communicates
with its parents

and tells the female
when it's ready to emerge.

The whole clutch starts
singing in a chorus.

This is when motherly love
comes in and she digs him out.

In this case it's us,

so we're the surrogate daddies here.

Let's see if this guy will
hatch right in my hand.

Yeah, yeah, yeah, yeah.

He's coming, he's coming,
he's coming, he's coming!

In the wild the mother's digging
would encourage them

to break out of their shells.

But here in Rom's maternity ward,
he's lending a helping hand.

Look at that! Look at that!

Absolutely amazing.

Gharials have been hatching
for millions and millions of years.

What I'm observing right now, is
something...it goes way back in time

to the time of the
dinosaurs and beyond.

(Yeah, yeah, yeah.)

'Seeing this fills me with a sense of
wonder, I can never shake.'

(Wow!)

This little hatchling,

can grow up to six metres,
20 feet long,

but at this stage it's so vulnerable.

(Oi! And there he is,
he's all the way out.)

This little newly hatched gharial
doesn't know it,

but he could just mean the future
for the survival of the species.

It seems like we've perfected the
art of breeding them in captivity

beautifully, but what's gonna happen
to them next? That is the problem.

Rom's 30-year struggle to save the
gharial is reaching its end game.

Right now, it's time to decide
whether there's still a place

for this magnificent creature
in our modern world.

The realisation that an animal
as fantastic as the gharial

could be on the verge of extinction,

should make us feel really
deeply ashamed of ourselves.

There's just so much more we can do,

and we're not doing it.

Next week, Natural World reveals

why the fate of
Portugal's cork forests,

one of the wildest places in Europe,
may depend on bottles of wine.

HARMONICA PLAYS

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