BBC Asia (2024) s01e05 Episode Script
Crowded Continent
1
Across Asia, vast fertile lands
support an ever-growing
human population.
In Vietnam alone,
the number of people has more
than doubled in the last 50 years.
This is the most
densely-populated continent of all -
home to 4.7 billion
..and counting.
More people live in Asia than
in the rest of the world combined.
Yet, in this crowded continent,
human settlements also offer unique
opportunities for those animals
that are bold enough to seek them.
Bhopal, central India.
During festivals,
the city fills with light.
But in the shadows,
a predator is on the prowl
..lured here by the promise
of easy prey.
A tiger.
Asia's largest big cat.
This female needs to
make a kill every week.
And the city has
rich hunting grounds.
The occasional loss of livestock
..is tolerated by the humans
who live here.
And the tigress has learnt
to become invisible.
Timing is everything.
She uses the same routes
as the people
..but never at the same time.
And her stealthy strategy pays off.
She has cubs.
A litter of four.
Tiger mothers usually
have only two cubs.
Quadruplets are a sign
that she's doing well.
But now, she's got her work cut out.
She must teach her mischievous cubs
how to go unnoticed.
These urban tigers have learnt
to thrive in the human world
..by staying out of the spotlight.
In Sri Lanka,
the largest of land mammals
takes a very different approach.
Asian elephants live
in higher densities here
than anywhere else on Earth.
To find enough food,
they roam for hundreds of miles.
But people are never far away.
That means new dangers
..but also new opportunities.
Fruit is tastier
than leaves and grass.
And on this road
you can often pick up a full meal.
But there is one bull who
takes things a stage further.
He doesn't wait patiently
by the roadside.
Instead, he uses his four-tonne body
to create a road-block
and demand a toll.
When he receives a payment,
he lets them past.
His persuasive charm
has earned him a reputation.
He's even been given a name - Raja.
He knows which vehicles
aren't worth bothering with
And which have the potential
to deliver a feast.
Raja's gentle nature
has won many hearts.
But other bulls here
don't share his diplomatic skills.
Their more assertive approach
doesn't get them anywhere.
And now, despite the risks,
entire families are showing up.
Elephant numbers are on the rise
in Sri Lanka.
Persuading people to hand over
their food
will be an increasingly valuable
skill.
One there is
plenty of time to learn.
This new behaviour is only possible
because of the mutual respect here.
Such tolerance exists among people
right across Asia
..including here -
Nara, in central Japan.
During the morning rush hour,
not all commuters walk on two legs.
Sika deer are more than
comfortable in this town.
They're free to roam
wherever they please.
This mutual understanding
has existed for generations.
A deer is believed,
in ancient times,
to have brought into the town
a divine messenger
riding on its back.
Ever since, sika deer here
have been considered sacred.
And today, they're celebrities.
They are hand-fed with
special deer crackers.
But every autumn,
the peace is disturbed.
Males start fighting for females
..and become a danger to people.
To avoid accidents,
their antlers are removed.
They will grow back in spring,
and their temporary loss
allow the deer to live in the city
without risk of hurting anyone.
But those males looking for a mate
now have a problem.
This stag's search has brought him
to the edge of the town.
A group of females.
Perfect.
But they are being guarded
..by a male from out of town,
with an intimidating set of antlers.
This posturing signals a challenge.
A slip now could cost him an eye.
Lacking antlers,
he's dependent on strength
..skill and sheer determination.
Even without weaponry,
he has beaten his opponent.
And the winners
get a chance with the females.
India -
home to more people
than any other country on Earth.
Over 1.4 billion.
Half the population
work in agriculture.
And here,
in the foothills of the Himalaya,
the millet crop is
ready for harvesting.
But a raid is being planned.
A troop of Himalayan langurs.
These fields contain the
best food for miles around.
The prospect of such
a good meal is irresistible.
The crops, however, are growing
on the other side of a river.
And the only bridge
is patrolled by dogs.
They regularly kill
intruding monkeys.
The langurs' only option
is to brave the rapids.
The dogs are closing in.
The baby has to cling on
to its mother for dear life.
These monkeys have made it
to a field full of food.
Much more nutritious than the
wild plants that grow higher up.
But the langurs must be alert.
A male keeps watch.
The langurs take refuge
in the nearby trees.
But now, they're trapped.
One wrong move could be fatal.
But langurs are clever.
They create a diversion.
The older adults
lead the dogs away
..and the others are able to escape.
The troop is re-united.
Everyone is home and safe.
Agriculture in India has shaped the
landscape for thousands of years.
Irrigating crops requires
an extensive network of channels,
dams and canals.
These features occasionally create
unexpected opportunities
for animals.
In Gujarat, in the west of India,
snakes are on the move.
These are checkered keelbacks
and they have a particular
destination in mind.
This drainage channel
might not look like much,
but it will soon be full of fish.
And the snakes seem to know it.
Fish travelling upstream
to reach reservoirs
must pass through a narrow gap.
There, the snakes await them.
But the only thing they seem
to be actually catching
..is each other.
They don't have long
to get their eye in.
The fish are only here
for a few days each year,
when water levels are at their peak.
And now, there is competition.
That is just showing off.
Jackpot!
Finally, the snakes have caught on.
And now they're getting ambitious
..going for even bigger fish.
But be careful what you wish for.
Such a stir
from one simple structure.
Human developments inevitably
affect the landscape.
And here in Asia, that influence
has become major and extensive.
Across the continent, people
are building in all directions,
faster than anywhere else on Earth.
In just a few decades,
Singapore has become totally urban.
And it's still expanding.
Today, two-thirds of the world's
mega-cities are in Asia.
And some have spread so far that
they've merged with one another.
In Japan, Tokyo has joined
with nearby Yokohama
and created the planet's
largest built-up area.
This is what is now known
as a megalopolis.
37 million people
have their homes here.
Such cities are surely the most
un-natural of our planet's habitats.
Taipei - the capital of Taiwan.
Here, an animal normally
found in forests
now lives surrounded by the glass
and concrete of a modern school.
On the fifth floor,
inside the library,
he's built a nest
..between a window and its shutters.
It's quiet, warm
and far from predators.
A great place for a squirrel
to sleep through the day.
But when he wakes up,
he has a problem.
Here, there is very little food.
To get to a tree where
there might be some,
he must travel from
one building to another
..and that is dangerous.
But this is no ordinary squirrel.
He has a super-power.
He can fly.
He has skin stretching
between his limbs
that enables him to glide
for 150 metres or so.
But to reach his destination
will be difficult.
Each take-off must be
from as high as possible
..because with every glide,
he inevitably loses height.
And travelling over the ground
is very dangerous indeed.
At last, the trees are in sight.
Just one more busy road to cross
and he'll be there.
Finally, a meal.
Another Taipei resident
manages to find all it needs
without having to commute.
A rhinoceros beetle
emerging in a city garden.
Males have only one thing
on their mind
..sex in the city.
This may seem an unlikely place
to find a mate.
But there's something here
that all rhinoceros beetles
find irresistible.
Ash trees.
Lots of females are already here,
feeding on the sweet sap.
This male approaches them
cautiously.
But he's not the first to arrive.
And some have much bigger horns.
Down
..but not out.
Rhinoceros beetles
don't give up easily.
But these ash trees have been
planted closer together
than they usually grow in the wild.
Which is why there are
so many rhinoceros beetles here.
And more males means more battles.
With such a small horn,
the odds of winning are low.
Sometimes you have
to rely on stealth.
Waiting for the other males
to start fighting
..and then sneaking past.
Finally, a female.
Rhinoceros beetles are one
of a select group of animals
able to thrive in Asian cities.
Bangkok, the capital of Thailand,
has a population
of ten million people.
Only 250 years ago,
this was all wetlands.
And between the skyscrapers,
remnants of that past remain.
This is Lumpini Park
and here, swamp-dwellers
still survive.
An Asian water monitor.
This young female is one
of the smallest in the park.
So her life here isn't easy.
Males dominate.
Some are over two metres long
..and all are expert at fishing.
There are 300 or so living here,
as dense a population of big lizards
as you can find anywhere.
So competition is fierce.
This small female will need to be
bold if she's to get her fair share.
A catch as big as this
attracts a crowd.
Their forked tongues enable them
to detect a scent
from half a mile away
..and soon many huge males arrive.
The female is undaunted.
Despite her small size,
she barges straight in.
But as more males gather,
they squabble.
Her chances don't look good.
When you can't get a look in,
other tactics might work.
Such as stealing.
This female now has her very
own fish head
..and she's not giving it up.
There's so much food here
that these lizards are thriving.
And seemingly,
finding little difficulty
in living alongside humans.
That is not a common ability.
Most animals need
a more natural world
and that is diminishing
as a consequence of
our ever-increasing numbers.
In Borneo, in just 50 years,
the human population has tripled,
whilst the size of its forest
has halved.
And one of the island's inhabitants,
which lives nowhere else,
has very special requirements.
Proboscis monkeys.
Their favourite food are the leaves
of a particular species of mangrove.
The youngest leaves
are the most nutritious,
so the monkeys are constantly on
the move, looking for fresh growth.
As the forest shrinks, these trees
are becoming more difficult to find.
Now, their search for food
is bringing the monkeys into
the human world
..that lies on the other side
of a 100 metre wide river.
These pipes are the only bridge
across it for miles.
But the monkeys don't use it.
They can swim.
The baby struggles to keep
its head above water.
Made it!
But their journey is far from over.
And now,
they are in human territory.
To reach the trees they are seeking,
the troop must cross
the outskirts of the city.
And that brings them
closer to people.
At last, on the edge of the city,
their favourite leaves.
The dangerous journey has paid off.
But a tiny, isolated patch
of mangroves like this
won't sustain them for long.
If they are to survive,
they will soon have to find
another patch somewhere.
Like so many animals
from the wilderness,
these monkeys face
an uncertain future.
But there is, however, one species
that has become increasingly
dependent on our towns and cities.
These swifts have just travelled
over 3,000 miles
from Sub-Saharan Africa to
Jerusalem, in the far west of Asia.
In the heart of this ancient city
they nest in walls
that have stood here
for 2,000 years
..the Western Wall.
It's one of the holiest sites
in Judaism,
and swifts doubtless have nested
here ever since it was built.
The cracks between the stones
are just the sort of nest sites
that swifts like.
Across the Middle East, these birds
rely on human structures.
And if they can, they return
to the same nest site each year.
This one is waiting
for its partner to arrive.
They pair for life,
but only come together
for the short breeding season.
After nine months apart,
they are united once again.
This couple are
among the lucky ones.
They have a chance
of raising a family this year.
But some will never find a home.
The urban world on which
they have relied is changing.
Old buildings are being replaced
by cliffs of glass and steel.
There are no
nooks and crannies here.
With fewer places to nest,
swift populations the world over
are in decline.
But every pair that breeds
successfully
brings hope for the species.
In this nest, good news.
The parents
are now raising two chicks.
Growing youngsters
need feeding every hour.
Swifts do everything on the wing,
from catching thousands of insects
to collecting water,
a task which requires
very precise aerial manoeuvres.
In a few weeks, these chicks
will also take to the skies.
They may then remain in the air,
continuously, for three years,
until they're mature enough
to return and breed themselves.
But as historic cities are
transformed by modern structures,
the birds will face
an even greater challenge.
We should surely leave enough space
for those few creatures
in the world who still
choose to live alongside us.
Filming animals living
alongside people
took the Asia team
into new territories.
Whilst most wildlife film-makers
work in the wilderness
..they found themselves
in the busiest
and most built-up parts
of the continent.
The challenges of filming
animals in human habitats
don't come much bigger
than they did in Sri Lanka.
With elephants on a busy road, the
priority is to keep everybody safe.
We did a recce yesterday
with Sam,
our incredibly experienced guide,
and he's identified two elephants
that are quite aggressive,
and just from that drive-by,
it's fairly evident
that they're quite aggressive!
That tusker's body language
was completely different.
He felt stressed being on the road.
And I felt stressed
being around him!
Just Just completely
unpredictable.
Interactions between people
and elephants can quickly escalate.
In Sri Lanka, conflicts frequently
result in fatalities on both sides.
Rangers patrol these roads,
and use firecrackers to scare
the more aggressive elephants away.
But not all the bulls here
are the same.
The rangers introduce the crew
to one whose calm nature
makes him safer to film.
Ah, dude, perfect.
That was great.
That was an awesome shot.
Raja.
He's got a very different
temperament
to all the other elephants
we've seen.
He's the calmest out of all of them,
and the most confident.
Justine has 30 years of experience
filming elephants
all over the world.
But she's never met an elephant
quite like Raja.
Today, he's decided to stand right
next to the vehicle in a shady spot,
which is a bit tricky, because I
don't know where to put the camera.
It's proving difficult
to get him to keep his distance.
There's no food.
No food, Raja.
We don't have anything.
Look, nothing.
Usually, filming the close-ups
is the hardest part.
But here, it's the wide shots
that are tough.
Whilst Justine works with Raja
..Emma-Louise wants to capture
the action from a different angle.
From inside a bus.
The challenge with filming
on a bus is that it's always
a completely different scenario.
So no two buses are the same.
The interior's
completely different.
It's kind of getting a feel for
how most buses are laid out.
You have different conductors,
different drivers,
the elephants are on
different sides of the road.
So no matter how well
you think you've planned
for the camera moves you want to do,
it's never the way you planned!
We're not allowed to direct
or instruct the conductors
or the driver at all,
because they're driving a public bus
on a public highway,
so we can't ask them to do anything.
Ah, wrong side, OK.
Meanwhile, Justine has enlisted help
to get some much-needed distance
from Raja.
He's talking to Raja,
basically, saying,
"It's OK, we don't have anything.
Go back to where you were."
Raja seems to look at him.
The way he speaks is just gentle.
They seem to have
a relationship, these two.
Now, you see, he's turned around.
He's going back to his patch.
Thanks to the ranger's
negotiating skills,
Justine can get to work
filming Raja at work.
I mean, compared to all
the other elephants,
he is the utter master
of road scavenging.
He's a bit of a legend.
After hours on the road,
the bus team feel like their plan
will never come together.
I think we've been on about
38 buses now in total,
maybe 40.
You need the perfect position
of the elephant,
you need the perfect position
of the driver.
All the stars just have to align.
Ah, this is a good bus
for that shot.
Finally
..persistence pays off.
I love it when
a plan comes together.
I think that's awesome.
That's really good. Nice.
Let me see.
In Sri Lanka,
elephants and humans overlap
more than anywhere else on Earth,
and so there will be challenges.
The human/wildlife conflict,
or coexistence,
is a tricky one here,
like it is everywhere.
A fighting over resources.
But here, the relationship
is one of tolerance.
An attitude which the Asia team
witnessed many times
whilst filming across
this spectacular continent.
Next time,
a journey into
the arid heart of Asia
..where life exists
on a knife edge
..and each day
is a fight for survival.
Across Asia, vast fertile lands
support an ever-growing
human population.
In Vietnam alone,
the number of people has more
than doubled in the last 50 years.
This is the most
densely-populated continent of all -
home to 4.7 billion
..and counting.
More people live in Asia than
in the rest of the world combined.
Yet, in this crowded continent,
human settlements also offer unique
opportunities for those animals
that are bold enough to seek them.
Bhopal, central India.
During festivals,
the city fills with light.
But in the shadows,
a predator is on the prowl
..lured here by the promise
of easy prey.
A tiger.
Asia's largest big cat.
This female needs to
make a kill every week.
And the city has
rich hunting grounds.
The occasional loss of livestock
..is tolerated by the humans
who live here.
And the tigress has learnt
to become invisible.
Timing is everything.
She uses the same routes
as the people
..but never at the same time.
And her stealthy strategy pays off.
She has cubs.
A litter of four.
Tiger mothers usually
have only two cubs.
Quadruplets are a sign
that she's doing well.
But now, she's got her work cut out.
She must teach her mischievous cubs
how to go unnoticed.
These urban tigers have learnt
to thrive in the human world
..by staying out of the spotlight.
In Sri Lanka,
the largest of land mammals
takes a very different approach.
Asian elephants live
in higher densities here
than anywhere else on Earth.
To find enough food,
they roam for hundreds of miles.
But people are never far away.
That means new dangers
..but also new opportunities.
Fruit is tastier
than leaves and grass.
And on this road
you can often pick up a full meal.
But there is one bull who
takes things a stage further.
He doesn't wait patiently
by the roadside.
Instead, he uses his four-tonne body
to create a road-block
and demand a toll.
When he receives a payment,
he lets them past.
His persuasive charm
has earned him a reputation.
He's even been given a name - Raja.
He knows which vehicles
aren't worth bothering with
And which have the potential
to deliver a feast.
Raja's gentle nature
has won many hearts.
But other bulls here
don't share his diplomatic skills.
Their more assertive approach
doesn't get them anywhere.
And now, despite the risks,
entire families are showing up.
Elephant numbers are on the rise
in Sri Lanka.
Persuading people to hand over
their food
will be an increasingly valuable
skill.
One there is
plenty of time to learn.
This new behaviour is only possible
because of the mutual respect here.
Such tolerance exists among people
right across Asia
..including here -
Nara, in central Japan.
During the morning rush hour,
not all commuters walk on two legs.
Sika deer are more than
comfortable in this town.
They're free to roam
wherever they please.
This mutual understanding
has existed for generations.
A deer is believed,
in ancient times,
to have brought into the town
a divine messenger
riding on its back.
Ever since, sika deer here
have been considered sacred.
And today, they're celebrities.
They are hand-fed with
special deer crackers.
But every autumn,
the peace is disturbed.
Males start fighting for females
..and become a danger to people.
To avoid accidents,
their antlers are removed.
They will grow back in spring,
and their temporary loss
allow the deer to live in the city
without risk of hurting anyone.
But those males looking for a mate
now have a problem.
This stag's search has brought him
to the edge of the town.
A group of females.
Perfect.
But they are being guarded
..by a male from out of town,
with an intimidating set of antlers.
This posturing signals a challenge.
A slip now could cost him an eye.
Lacking antlers,
he's dependent on strength
..skill and sheer determination.
Even without weaponry,
he has beaten his opponent.
And the winners
get a chance with the females.
India -
home to more people
than any other country on Earth.
Over 1.4 billion.
Half the population
work in agriculture.
And here,
in the foothills of the Himalaya,
the millet crop is
ready for harvesting.
But a raid is being planned.
A troop of Himalayan langurs.
These fields contain the
best food for miles around.
The prospect of such
a good meal is irresistible.
The crops, however, are growing
on the other side of a river.
And the only bridge
is patrolled by dogs.
They regularly kill
intruding monkeys.
The langurs' only option
is to brave the rapids.
The dogs are closing in.
The baby has to cling on
to its mother for dear life.
These monkeys have made it
to a field full of food.
Much more nutritious than the
wild plants that grow higher up.
But the langurs must be alert.
A male keeps watch.
The langurs take refuge
in the nearby trees.
But now, they're trapped.
One wrong move could be fatal.
But langurs are clever.
They create a diversion.
The older adults
lead the dogs away
..and the others are able to escape.
The troop is re-united.
Everyone is home and safe.
Agriculture in India has shaped the
landscape for thousands of years.
Irrigating crops requires
an extensive network of channels,
dams and canals.
These features occasionally create
unexpected opportunities
for animals.
In Gujarat, in the west of India,
snakes are on the move.
These are checkered keelbacks
and they have a particular
destination in mind.
This drainage channel
might not look like much,
but it will soon be full of fish.
And the snakes seem to know it.
Fish travelling upstream
to reach reservoirs
must pass through a narrow gap.
There, the snakes await them.
But the only thing they seem
to be actually catching
..is each other.
They don't have long
to get their eye in.
The fish are only here
for a few days each year,
when water levels are at their peak.
And now, there is competition.
That is just showing off.
Jackpot!
Finally, the snakes have caught on.
And now they're getting ambitious
..going for even bigger fish.
But be careful what you wish for.
Such a stir
from one simple structure.
Human developments inevitably
affect the landscape.
And here in Asia, that influence
has become major and extensive.
Across the continent, people
are building in all directions,
faster than anywhere else on Earth.
In just a few decades,
Singapore has become totally urban.
And it's still expanding.
Today, two-thirds of the world's
mega-cities are in Asia.
And some have spread so far that
they've merged with one another.
In Japan, Tokyo has joined
with nearby Yokohama
and created the planet's
largest built-up area.
This is what is now known
as a megalopolis.
37 million people
have their homes here.
Such cities are surely the most
un-natural of our planet's habitats.
Taipei - the capital of Taiwan.
Here, an animal normally
found in forests
now lives surrounded by the glass
and concrete of a modern school.
On the fifth floor,
inside the library,
he's built a nest
..between a window and its shutters.
It's quiet, warm
and far from predators.
A great place for a squirrel
to sleep through the day.
But when he wakes up,
he has a problem.
Here, there is very little food.
To get to a tree where
there might be some,
he must travel from
one building to another
..and that is dangerous.
But this is no ordinary squirrel.
He has a super-power.
He can fly.
He has skin stretching
between his limbs
that enables him to glide
for 150 metres or so.
But to reach his destination
will be difficult.
Each take-off must be
from as high as possible
..because with every glide,
he inevitably loses height.
And travelling over the ground
is very dangerous indeed.
At last, the trees are in sight.
Just one more busy road to cross
and he'll be there.
Finally, a meal.
Another Taipei resident
manages to find all it needs
without having to commute.
A rhinoceros beetle
emerging in a city garden.
Males have only one thing
on their mind
..sex in the city.
This may seem an unlikely place
to find a mate.
But there's something here
that all rhinoceros beetles
find irresistible.
Ash trees.
Lots of females are already here,
feeding on the sweet sap.
This male approaches them
cautiously.
But he's not the first to arrive.
And some have much bigger horns.
Down
..but not out.
Rhinoceros beetles
don't give up easily.
But these ash trees have been
planted closer together
than they usually grow in the wild.
Which is why there are
so many rhinoceros beetles here.
And more males means more battles.
With such a small horn,
the odds of winning are low.
Sometimes you have
to rely on stealth.
Waiting for the other males
to start fighting
..and then sneaking past.
Finally, a female.
Rhinoceros beetles are one
of a select group of animals
able to thrive in Asian cities.
Bangkok, the capital of Thailand,
has a population
of ten million people.
Only 250 years ago,
this was all wetlands.
And between the skyscrapers,
remnants of that past remain.
This is Lumpini Park
and here, swamp-dwellers
still survive.
An Asian water monitor.
This young female is one
of the smallest in the park.
So her life here isn't easy.
Males dominate.
Some are over two metres long
..and all are expert at fishing.
There are 300 or so living here,
as dense a population of big lizards
as you can find anywhere.
So competition is fierce.
This small female will need to be
bold if she's to get her fair share.
A catch as big as this
attracts a crowd.
Their forked tongues enable them
to detect a scent
from half a mile away
..and soon many huge males arrive.
The female is undaunted.
Despite her small size,
she barges straight in.
But as more males gather,
they squabble.
Her chances don't look good.
When you can't get a look in,
other tactics might work.
Such as stealing.
This female now has her very
own fish head
..and she's not giving it up.
There's so much food here
that these lizards are thriving.
And seemingly,
finding little difficulty
in living alongside humans.
That is not a common ability.
Most animals need
a more natural world
and that is diminishing
as a consequence of
our ever-increasing numbers.
In Borneo, in just 50 years,
the human population has tripled,
whilst the size of its forest
has halved.
And one of the island's inhabitants,
which lives nowhere else,
has very special requirements.
Proboscis monkeys.
Their favourite food are the leaves
of a particular species of mangrove.
The youngest leaves
are the most nutritious,
so the monkeys are constantly on
the move, looking for fresh growth.
As the forest shrinks, these trees
are becoming more difficult to find.
Now, their search for food
is bringing the monkeys into
the human world
..that lies on the other side
of a 100 metre wide river.
These pipes are the only bridge
across it for miles.
But the monkeys don't use it.
They can swim.
The baby struggles to keep
its head above water.
Made it!
But their journey is far from over.
And now,
they are in human territory.
To reach the trees they are seeking,
the troop must cross
the outskirts of the city.
And that brings them
closer to people.
At last, on the edge of the city,
their favourite leaves.
The dangerous journey has paid off.
But a tiny, isolated patch
of mangroves like this
won't sustain them for long.
If they are to survive,
they will soon have to find
another patch somewhere.
Like so many animals
from the wilderness,
these monkeys face
an uncertain future.
But there is, however, one species
that has become increasingly
dependent on our towns and cities.
These swifts have just travelled
over 3,000 miles
from Sub-Saharan Africa to
Jerusalem, in the far west of Asia.
In the heart of this ancient city
they nest in walls
that have stood here
for 2,000 years
..the Western Wall.
It's one of the holiest sites
in Judaism,
and swifts doubtless have nested
here ever since it was built.
The cracks between the stones
are just the sort of nest sites
that swifts like.
Across the Middle East, these birds
rely on human structures.
And if they can, they return
to the same nest site each year.
This one is waiting
for its partner to arrive.
They pair for life,
but only come together
for the short breeding season.
After nine months apart,
they are united once again.
This couple are
among the lucky ones.
They have a chance
of raising a family this year.
But some will never find a home.
The urban world on which
they have relied is changing.
Old buildings are being replaced
by cliffs of glass and steel.
There are no
nooks and crannies here.
With fewer places to nest,
swift populations the world over
are in decline.
But every pair that breeds
successfully
brings hope for the species.
In this nest, good news.
The parents
are now raising two chicks.
Growing youngsters
need feeding every hour.
Swifts do everything on the wing,
from catching thousands of insects
to collecting water,
a task which requires
very precise aerial manoeuvres.
In a few weeks, these chicks
will also take to the skies.
They may then remain in the air,
continuously, for three years,
until they're mature enough
to return and breed themselves.
But as historic cities are
transformed by modern structures,
the birds will face
an even greater challenge.
We should surely leave enough space
for those few creatures
in the world who still
choose to live alongside us.
Filming animals living
alongside people
took the Asia team
into new territories.
Whilst most wildlife film-makers
work in the wilderness
..they found themselves
in the busiest
and most built-up parts
of the continent.
The challenges of filming
animals in human habitats
don't come much bigger
than they did in Sri Lanka.
With elephants on a busy road, the
priority is to keep everybody safe.
We did a recce yesterday
with Sam,
our incredibly experienced guide,
and he's identified two elephants
that are quite aggressive,
and just from that drive-by,
it's fairly evident
that they're quite aggressive!
That tusker's body language
was completely different.
He felt stressed being on the road.
And I felt stressed
being around him!
Just Just completely
unpredictable.
Interactions between people
and elephants can quickly escalate.
In Sri Lanka, conflicts frequently
result in fatalities on both sides.
Rangers patrol these roads,
and use firecrackers to scare
the more aggressive elephants away.
But not all the bulls here
are the same.
The rangers introduce the crew
to one whose calm nature
makes him safer to film.
Ah, dude, perfect.
That was great.
That was an awesome shot.
Raja.
He's got a very different
temperament
to all the other elephants
we've seen.
He's the calmest out of all of them,
and the most confident.
Justine has 30 years of experience
filming elephants
all over the world.
But she's never met an elephant
quite like Raja.
Today, he's decided to stand right
next to the vehicle in a shady spot,
which is a bit tricky, because I
don't know where to put the camera.
It's proving difficult
to get him to keep his distance.
There's no food.
No food, Raja.
We don't have anything.
Look, nothing.
Usually, filming the close-ups
is the hardest part.
But here, it's the wide shots
that are tough.
Whilst Justine works with Raja
..Emma-Louise wants to capture
the action from a different angle.
From inside a bus.
The challenge with filming
on a bus is that it's always
a completely different scenario.
So no two buses are the same.
The interior's
completely different.
It's kind of getting a feel for
how most buses are laid out.
You have different conductors,
different drivers,
the elephants are on
different sides of the road.
So no matter how well
you think you've planned
for the camera moves you want to do,
it's never the way you planned!
We're not allowed to direct
or instruct the conductors
or the driver at all,
because they're driving a public bus
on a public highway,
so we can't ask them to do anything.
Ah, wrong side, OK.
Meanwhile, Justine has enlisted help
to get some much-needed distance
from Raja.
He's talking to Raja,
basically, saying,
"It's OK, we don't have anything.
Go back to where you were."
Raja seems to look at him.
The way he speaks is just gentle.
They seem to have
a relationship, these two.
Now, you see, he's turned around.
He's going back to his patch.
Thanks to the ranger's
negotiating skills,
Justine can get to work
filming Raja at work.
I mean, compared to all
the other elephants,
he is the utter master
of road scavenging.
He's a bit of a legend.
After hours on the road,
the bus team feel like their plan
will never come together.
I think we've been on about
38 buses now in total,
maybe 40.
You need the perfect position
of the elephant,
you need the perfect position
of the driver.
All the stars just have to align.
Ah, this is a good bus
for that shot.
Finally
..persistence pays off.
I love it when
a plan comes together.
I think that's awesome.
That's really good. Nice.
Let me see.
In Sri Lanka,
elephants and humans overlap
more than anywhere else on Earth,
and so there will be challenges.
The human/wildlife conflict,
or coexistence,
is a tricky one here,
like it is everywhere.
A fighting over resources.
But here, the relationship
is one of tolerance.
An attitude which the Asia team
witnessed many times
whilst filming across
this spectacular continent.
Next time,
a journey into
the arid heart of Asia
..where life exists
on a knife edge
..and each day
is a fight for survival.