Original subtitles

Cities...

..the fastest growing habitat on the planet.

A land of opportunity...

..for animals of all shapes and sizes.

This unnatural world... CAR HORN BEEPS

..presents unique challenges.

But for those able to adapt...

..and take advantage of the riches on offer...

..the urban jungle is quickly becoming the new wild.

In the last 30 years,

the world's urban areas have almost tripled in size,

changing at a rate wildlife has never experienced before.

Some animals have adapted to urban life with surprising ease

and made cities their home.

Others have found that keeping one foot in the wild,

and commuting into town, they make the most of both worlds.

But there is another group...

..with the most surprising stories of all.

Animals that once lived

where our cities are now built.

Today, they find themselves fighting for their place in the land

that once belonged to them.

These are the wild outcasts.

Costa Rica...

..a tropical tourist hotspot,

famed for its incredible wildlife encounters.

And this Pacific coastal town is home to some of the most

intelligent monkeys in the world.

are in a perilous position...

..struggling to adapt and fit into a changing world.

White-faced capuchins have the largest brain-to-body ratio

of any primate, other than us.

And the wealth of tasty and exotic goodies tourists bring to the beach

makes for hot property worth defending.

Around 20-strong, this is an average sized troupe.

And this grizzled alpha male is in charge.

He lost an arm fighting to keep hold of this territory.

Him and his troupe defend the tourist beach like they would

a fruiting tree in the forest.

They know there's more to be gained than a few measly leftovers.

They've learnt to play the naive tourists to get their hands

on a seemingly never ending supply of food...

..employing a variety of cunning tactics.

There's the sweet and gentle...

..the butter wouldn't melt...

..and the cheeky chappie.

But these aren't natural behaviours.

These monkeys should have an innate fear of humans.

But the alpha male has become so confident,

he's happy to assert his dominance.

CHILD CRIES

And the more the capuchins expect food,

the more aggressively they pursue it.

By continuing to feed them, tourists are only fuelling

this bad behaviour.

It's even led to them developing a criminal streak.

They wait patiently for people

to leave their belongings on the beach...

..before moving in to steal any food.

Capuchins are one of the only primates known to use tools.

So, opening unattended luggage is no problem.

But their delinquent behaviour and bullying tactics

are making them unpopular.

And right now, these capuchins face an uncertain future.

They may be relocated or, worse still, euthanized,

unless the tourists change their habits.

Finding ways to protect wildlife from the problems we create

is becoming increasingly important...

..because urban areas will only continue

to swallow natural habitats.

And cities support just 20% of the wildlife that lived

on the land before they were built.

It's never been more important

to create space for nature in the urban world.

If we don't, we risk losing it altogether.

It's predicted that by the middle of the century,

50% of the world's species will be in decline.

And that's in part because more and more land is being cultivated

to feed our ever-growing population.

The scale of the problem couldn't be more obvious

than in Sri Lanka...

..where forests are fast being replaced with crops...

..putting people in direct conflict with the largest land mammal of all,

elephants.

As their jungle disappears and is farmed to feed us,

they've discovered it makes potentially easy pickings.

Under the cover of darkness, more elephants head into town

to try their luck.

The local inhabitants guard their livelihood...

..armed with lights, firecrackers, and flares.

It's a risky strategy for the elephants.

But hunger drives them on.

Each year, this conflict claims the lives of over 200 elephants

and 80 people.

The explosions across the region mark the start

of the nightly battle.

It's an outcast claim to lost lands

versus a relentlessly expanding civilisation.

The elephants retreat.

But to grow up to three metres tall, and weigh five tonnes,

they need to eat as much as 150 kilos a day.

They will be back.

With the encounters taking their toll on both sides,

a ceasefire is well overdue.

People here are developing ways to try and keep the peace.

Farmers have found that planting a barrier of fruit trees

around their crops helps...

..because elephants have the best sense of smell in the animal kingdom

and find the smell of citrus repellent.

The trees act as a sustainable buffer that encourages the elephants

to feed back in the forest.

Electric fences that surround some of the villages help too.

But the elephant encounters that happen outside the fences

are the most dangerous.

And for some kids, this road through a notorious

elephant corridor is the only way to school.

It's a potentially deadly commute on foot.

But the solution is simple.

An elephant school bus.

Each morning, the bus picks up kids from the surrounding area

and drives them safely to school.

A journey of fear is now a journey of wonder.

Elephants don't perceive large vehicles as a threat

in the same way they do a person on foot,

making for a peaceful passage.

These Sri Lankan communities are finding ways to live alongside

the largest of animals.

But across the world, elephants are losing their natural

habitat and being targeted by poachers for their ivory.

The global population has shrunk by a shocking 95%

in the last century.

It's a crisis desperately in need of solutions.

Peaceful coexistence with large and dangerous

animals is possible.

All up the east coast of America, luxury developments are built

on prime alligator habitat.

Golf resorts.

But at South Carolina's Kiawah Island, the water hazards,

rough and rolling greens are a paradise for golfers

and gators alike.

That's because each species knows its place here.

The ponds belong to the gators,

and the fairways are reserved for the golfers.

But each spring, as males compete for the best territory and the best

females, the boundaries become blurred.

This four-metre male guards his network

of ponds and channels.

And he protects his love interest too,

whether she's interested or not.

But there's no rush.

New science shows that alligators can actually mate for life.

HE CALLS

He warns off the smaller males by broadcasting his dominance.

An infrasonic, then, bellowing call...

HE CALLS

..that can be heard from three miles away.

HE CALLS

Happy he won't be interrupted, he makes his move.

But she needs some wooing.

Turning on his charm, he rests his head on her back

and blows her romantic bubbles.

During a brief moment underwater, the pair mate.

With the female spoken for, the battle-scarred youngsters walk

the course in search of their own territory.

But all the best spots are taken.

Chasing and posturing is usually enough to end a dispute.

With a bite three times more powerful than a lion,

it's better to retreat than risk injury.

Even though it's built on alligator territory,

this high-end human playground provides for both people

and wildlife.

Striking the right balance with animals we naturally fear

can be difficult.

But cities will continue to attract uninvited wild guests.

Because, sometimes, they offer them everything

they need to survive.

And those animals small enough to take advantage

of these opportunities unnoticed can make it big.

Once a tiny desert resort, this twinkling North American city

Almost everything has been brought here by humans.

Hidden in plain sight, one small but deadly

arachnid is thriving in the shiny new desert oasis.

The bark scorpion.

They might be just a few centimetres long,

but they are the most venomous scorpions in North America.

And despite the city being built on their land,

they have flourished.

In summer, when males hunt for a partner,

action on the Strip gets pretty hot.

Bark scorpions have 12 eyes, but their vision is poor.

They can only see shades of light and dark.

So, males follow the scent of a potential mate, using

specialised sensory organs on their belly called pectines.

But finding her is only half the battle.

Locking pincers, she tests his strength and suitability

as a father.

He needs to be careful.

One false move and she'll have him for dinner.

She will carry her fertilised eggs for up to a year.

And if times get hard, she'll reabsorb them.

But in this city of excess, that's unlikely.

Bark scorpions feed on insects like cockroaches and crickets,

providing a useful pest control service.

She stuns her captive with a potent neurotoxin...

..and dissolves parts of the body with enzymes before eating it.

When she's ready, she gives birth to up to 30 helpless young,

that she will carry on her back until they are old enough

to survive on their own.

In her six-year life span, she can produce 150 babies,

fuelling a population boom.

As one of the only life forms able to survive at nuclear test sites,

scorpions may not be too welcome, but it looks like they are

here to stay.

Because cities can offer food, shelter, and somewhere

to raise a family,

the most tenacious wild animals will find a way to live

between the cracks of the urban world,

no matter what we throw at them.

One notorious outcast has been so successful

at avoiding our attempts to eradicate it, that it's now common

in nearly every human settlement in the world.

The brown rat.

In fact, city living suits them so well,

they are now only found alongside us.

15 million live in the UK alone.

And like the scorpions in Vegas, their extraordinary ability

to reproduce is the secret to their success.

By filming under controlled conditions, we can reveal why.

Safe in their nest, this litter is just ten days old,

and about to open their eyes.

And in less than two months' time, the young females will be able

to have babies of their own...

and from then on, could have a litter of 11

every three weeks.

That's up to 3,000 descendants a year.

They explore the world around them with a nose that will eventually

be more sensitive than a bloodhound's.

For now, Mum wants to keep them safe.

But just a few weeks later, the young females are ready to leave

and start their own family.

It's a dangerous time.

More than 50% of rats die within ten days of leaving the nest.

So, they are naturally wary of anything unfamiliar.

But few things stand in their way.

They can squeeze through a gap a quarter of their size.

Cavity walls in modern buildings provide perfect hidden highways.

With flexible feet and fine claws, rats can climb around inside them,

even when upside down.

The outside world presents different challenges.

But it's rats' innate skills that have made them such

an urban success story.

As they find their way around, rats make a mental map

of new surroundings.

And with soft pads on their feet, can grip even smooth surfaces.

They are one of the few mammals, other than us, able to plan complex

routes to reach a goal.

DOG BARKS

Expert tightrope walkers, rats use their flexible tails

as a counterbalance.

And, when needed, to give them control on tricky descents.

With powerful back legs, rats can leap

more than a metre.

At the merest hint of us, they flee.

Supple and strong, they can survive a fall

of over two metres.

In the shadows, rats have all the skills they need to ensure

the survival of their species...

..right under the nose of their age-old enemy.

However, life in the city can be more accommodating

for outcasts with a better public image.

Built on prime marshlands, the capital of the Netherlands

is synonymous with a bird that lived in these waterways long

before the city was built...

..the grey heron.

They've managed to survive here, feeding on their natural diet

of fish and frogs.

But in extra cold winters, the city's hundred miles

of waterways can freeze solid, locking their food out of reach.

Some have learnt that if they get their timing right,

there are still places in town to get a good meal.

They head to the fish market, just before it closes at 5pm.

And they wait.

The bold come down, hawking for scraps,

even before the market goers have left.

But there are slim pickings this early.

As darkness descends, so do the rest of the herons.

Dancing between the trolleys and vans, they fight

for the leftovers.

Feeding after dark is highly unusual behaviour.

Herons are hard-wired to roost at night to avoid predators.

But the fish market provides them a vital lifeline

in the long, cold winters.

It's a race to clear up as fast as possible,

head-to-head with their garbage guzzling inner-city rival.

By adapting to the changing urban world, the herons have secured

a future in the heart of town.

And because they are established in the city,

some have even formed remarkable relationships.

In a sleepy suburb, one lucky heron has been welcomed

with open arms.

Diny Dieperink is preparing breakfast for her good friend, Kiri.

Kiri!

Kiri!

Kiri!

It's beautiful. It's beautiful.

The respectful bond between Diny and Kiri has mutual benefits.

It's a winning strategy that's proving successful

on a far larger scale,

helping to bring one of Florida's state mascots back

from the brink of extinction.

The town of Crystal River is famous for its glass-like,

spring-fed rivers that originate in the heart of the town.

But the biggest tourist attraction here, by far,

are its manatees.

Growing to four metres, and weighing a tonne and a half,

these huge vegetarians are also known as sea cows.

Despite their size, they don't have much

insulating body fat.

When the sea temperature drops, they can die from cold stress,

a condition similar to frostbite.

So, in winter they head into town, where a warm welcome awaits.

Calves rely on their mothers until they are two years old

and make the journey side by side.

Swimming an average of 5mph,

they cruise past waterfront condos and jetties on the way.

And when hungry, calves suckle from teats

under mum's front flippers.

Every three to five minutes, they come to the surface to breathe.

When they reach Crystal River's springs, they can relax.

Here, 45 million litres of water pour out of the ground each day

at a constant 22 degrees...

..the perfect temperature for manatees to avoid cold stress.

In the warmth of the spring, mum and baby can slow

down and save energy.

When it's really cold, over 500 manatees pack themselves

into the toasty springs.

That's almost 5% of the world's population.

But 30 years ago, the story was very different.

Pollution and severe injuries from boat traffic

meant their population all but collapsed,

prompting a large-scale community initiative to protect them.

Today, over 100 volunteer guardians keep a watchful eye

over the manatees.

Strict speed limits control boat traffic.

And visitors are educated on how to behave around the manatees.

What we normally do is get up, maybe three to six feet away

from them, then we stop.

Here's where we passively observe them.

When in doubt, just remember to float.

It'll be perfectly OK.

The scheme has been an overwhelming success.

Manatee tourism attracts up to 250,000 tourists a year...

..generating an income of more than $30 million.

And in 2017, manatees were taken off the endangered species list.

It's no secret that we need to protect nature.

Only now are we starting to realise that our towns and cities

have a role to play in this.

What's perhaps most surprising is that it can be a two-way street.

In south-east Asia, one of the fastest birds

in the world has developed such a productive relationship

with people, they have had whole cities purpose-built for them.

Swiftlets are traditionally found within deep cave systems,

but have been invited into people's homes

and specially-built swiftlet hotels.

This male is building his nest, using extra thick and sticky saliva,

produced in a gland under his tongue.

Over 40 days, he adds layer upon layer, until his tiny

cup-shaped nest is finished.

Pairs have up to three clutches of one to two chicks a year.

Once they've fledged, the hotel owners move

in and harvest the nest.

The main ingredient in a traditional delicacy,

bird's nest soup.

The birds are doing so well, they may soon be classified

as an entirely new subspecies, the house swiftlet,

evolved to live within our four walls.

Everyone wins.

They are guaranteed shelter and safety,

and the farmers get $2,000 a kilo for their nest...

..completely changing the lives of people here, like Dawud.

The more we learn, it becomes clear that when managed

in the right way, having wild neighbours can help ensure a secure

future for both of us.

And nowhere is this more evident than on San Clemente Island...

..where a wild guardian angel gives the US military

unexpected protection.

Face...

The tiny speck in the Pacific Ocean is just four miles wide

and 21 miles long.

And a highly sensitive US naval warfare facility.

It's the only place in the world the US Navy are authorised

to practise sea to land bombardment.

And they aren't the only deadly force here.

A little-known predator is watching their every move.

The San Clemente fox is the island's largest carnivore.

But at the size of a domestic cat, it's one of the smallest canine

species in the world.

With endless drills and exercises, the barren south end

of the island is inhospitable.

But these foxes thrive in the north,

living in the Navy's town,

amongst its personnel

and close to the airstrip.

It's the nearest thing to hustle and bustle in this corner

of the Pacific.

This vixen has a den full of cubs, right by the busy port.

It's the perfect spot for her to raise a family...

..because foxes have access all areas, to the highest security base.

But she has her work cut out.

Normally, foxes have just two cubs a year.

This vixen has three.

The cubs will learn everything they need to survive

here from their mum.

She's teaching them to eat a wide range of foods,

from lizards and small mammals to insects and even birds' eggs.

Climbing trees doesn't come easy to a five-week-old cub.

But the rewards are worth it.

San Clemente foxes don't exist anywhere else in the world.

And 15 years ago, the species was listed as critically endangered.

The Navy were warned that if the fox numbers dropped any further,

they'd been evicted from the island to allow them to recover.

So the military now invest $7 million a year

into the protection of the island's wildlife.

They have even put in place a team of scientists that run a fox

awareness program to track and monitor the population.

Today, the foxes are no longer considered endangered.

And the Navy are now not just looking out for them

because they have to - there's real affection

here for these tiny predators.

The foxes bring out a warm and caring side of the military.

Protecting their population safeguards the Navy's presence

on the island, too.

Like the foxes, some wildlife has been able to survive,

even thrive, alongside us...

..making the most of the opportunities our world offers.

As wild residents...and commuters.

But as urban areas expand...

..more and more wildlife

will need our help if it's to have a future.

And where we have given it a chance, there is hope.

Half a century ago, New York had some of the most

polluted waterways in the world.

But efforts to clean them up have paid dividends.

And recently, scientists like Howard Rosenbaum have witnessed

an amazing recovery.

Right here in New York, we're seeing the benefits of five

decades of protection, and we're seeing the fish stocks

recover from depleted numbers.

Waders and fishing birds are flourishing in what had become

empty marshlands.

Pods of dolphins, hundreds strong,

can now be found in sight of the city.

But the biggest surprise is the return of one

of the Atlantic's giants...

..the humpback whale.

For quite some time, it was considered probably

the sighting of a lifetime.

I mean, just to think about the fact that you can be strolling

on the beach and see a humpback.

People are not used to having humpbacks

in and around New York.

The fish they prey on is now so abundant that New York's coast

has become a perfect summer stopover for the whales.

We see healthy animals foraging here, feeding right close

to our shores. I mean, it's phenomenal.

We are at a critical point in history.

Our relationship with the planet is increasingly fragile.

We're consuming more than we ever have done.

And while our population is booming,

it's estimated we've last half

of the world's wildlife in just 40 years.

But in our cities, the newest and fastest growing

habitat on Earth...

..we can make a difference...

..by simply giving nature the space and resources it needs.

Even for the biggest and most surprising of animals,

the urban jungle CAN be a place of opportunity.

So, what happens next is up to us.

As we've discovered in this series, if you give animals a chance

in cities, they can thrive.

And that having a close relationship with nature

is often hugely rewarding.

I think we're hard-wired to appreciate nature and appreciate

animals, so even on a Navy range, the fact that people

can occasionally see wildlife really seems to make people happy.

Research is now proving that exposure to the natural world

has profound positive effects on our mental wellbeing.

of anxiety and mood disorders.

Keeping in touch with nature has been shown to counter this.

The natural world stimulates parts of the brain associated

with love and empathy...

..and lowers stress levels.

The mental benefits are believed to be profound.

Studies estimate that London parks alone save the NHS

£370 million a year.

Whether it's the breeze against your skin,

the smells in the air, nature is an antidote

to fast-paced city living.

There really is something very therapeutic happening,

just by being in a green space.

Beth Collier is part of a new wave of psychotherapists,

using a connection with nature to help alleviate the pressures

of modern life.

She thinks the young generation need the most help.

Nature's no longer normal for young people,

and it's up to us, the older generation,

to make sure we pass on that awareness to younger children.

Surveys show that three quarters of children in the UK spend

less time outdoors than prison inmates.

So Beth runs sessions helping youngsters like Kamal engage

and connect with nature.

Even ten minutes, spending time observing and tuning

into the natural environment will help you to feel part

of something much bigger than yourself.

You don't have to go far to find it.

Cities already have a surprising number of green spaces.

Today, even in the most unexpected corners of London,

nature is being brought into the city.

And one initiative is encouraging people to get involved.

Local resident Gerry Tissier has seen an overwhelming response.

10X Greener is a project in our community to see

what we can do to green up our streets so that they're good

for wildlife and they're good for people as well.

The moment that you get people out of their houses,

that's the moment that things begin to change.

All the kind of spaces that you get on streets,

you suddenly start thinking, "Oh, we could put a planter there,"

or, "We could green up that corner."

People from all over the community are collaborating,

not just for the benefit of wildlife, but also

for their own wellbeing.

Gardener John Little has been tasked with enriching

Hackney's Clapton estate.

When people came out of their houses and we were chatting to them,

immediately we realised that colour was a big,

big thing, and food.

Those two things combined, make better biodiversity

make better places.

If you create decent public spaces and then people are drawn out to it,

if there's wildlife there, if there's colour there,

people really notice that.

And once they notice the public space, then the ambience and the way

the place feels, feels completely different.

And with projects like this springing up across the capital

city, huge changes are being made.

It's about getting outside more and enjoying the city's

great outdoors more. Getting down to allotments and nature reserves,

stuff which thousands of Londoners are already doing.

But what if we did it even more?

Thanks to people like Dan Raven-Ellison,

London is already a global leader in city greening and urban nature.

And in 2019, the capital is set to become the world's

first ever national park city.

47% of London is physically green, another 2.5% is blue,

so the canals, the rivers, the ponds.

By international standards,

London is a truly remarkable urban landscape.

And it's a movement of people working together to make the city

greener, healthier and wilder, through everyday things.

Start planting stuff on our streets and on our roofs and get out

onto our canals and rivers, getting children outside far

more in schools.

If enough of us do these simple things,

it can really transform a landscape.

Anyone can get involved in creating new habitats and space for wildlife.

And this idea is going global.

Dedicated people everywhere are working to safeguard our

access to nature.

If we're respectful of other creatures' environments

and we are able to share that with them, we get the benefit

and the privilege of having them around longer for children

and grandchildren to see.

Conserving what we have for wildlife is important, not just

for the wildlife, but for our own life and satisfaction.

It's predicted by 2050, nearly 70% of the world's population will live in cities.

If we all embrace the idea of making the urban environment a wilder

place, there's little doubt it will help us lead happier,

healthier and less stressful lives.