All language subtitles for zre

Africa.

No continent on Earth today has such spectacular wildlife.

At its heart lies a vast tropical rainforest.

Over a million square miles of wilderness,

much of it still unexplored...

...even now.

There are more species of animals and plants in these jungles

than anywhere else on the continent.

But even in this land of plenty...

...wildlife now faces major challenges.

The forests of the Ivory Coast

contain over 1,500 species of plant,

but some are very difficult to get at...

...even for one of the most intelligent of animals.

Chimpanzees.

The elders in this group know where to find the most nutritious food

and how to extract it.

But if they are to survive to adulthood,

the youngsters must learn these skills from their parents.

This young female is five years old...

...old enough to be given an important lesson.

And this is her teacher.

Her mother.

The lesson is how to crack a nut.

Using tools like this is so complex

that it has only been mastered by a handful of chimpanzee communities.

This is a skill that has been practiced by chimps for several thousand years.

Time to try for herself.

She needs to find a better tool.

Small rocks just don't have the clout.

And larger ones are too cumbersome.

Wood is both light and strong...

...but not strong enough.

Back to teacher.

It may take a young chimp up to a decade to perfect

the skills it needs for nut cracking.

But she's already mastered one thing.

When her fingers can't reach the nut inside...

...she strips down a branch to size...

...and makes herself a spoon.

She'll learn to use many tools in her life...

...and eventually she'll share this knowledge

with youngsters of her own,

enabling them to harvest the riches of their rainforest home.

The sheer abundance of life in the rainforests

is rivaled by that on the eastern side of the continent.

The Great Rift Valley runs for 4,000 miles down the length of Africa.

It developed some 3 million years ago,

when a giant plume of molten rock pushing up from the depths

cracked the Earth's crust apart.

Fresh water began to accumulate on the floor of this rift...

...and a chain of lakes developed.

These lakes are now one of the richest freshwater habitats

to be found anywhere.

One single family of fish here... the cichlids

has evolved into more than 1,500 different species.

This might look like paradise,

but competition between these cichlid species is intense.

This crowded world is a dangerous one.

Baby fish, after all, make a tasty meal.

So, many cichlid mothers have developed a very effective way

of keeping their offspring safe.

They use their mouths as a mobile nursery.

It's a safe haven where the fry can stay until danger has passed.

When the coast is clear, she releases them.

This kind of behaviour starts when the cichlid female

picks up her newly laid eggs and holds them in her mouth to keep them safe.

During spawning, her mate flashes his yellow tail spots

to encourage her to keep laying.

As each batch of eggs emerges,

she scoops them up.

But this couple are being watched...

...by cuckoo catfish.

They work as a gang

and devour as many cichlic eggs as they can find.

Then, in the middle of all this activity,

one of the catfish also spawns.

The cichlic mother collects every egg she can see.

Now, by herself, she must wait

while the eggs in her mouth develop.

It will take three weeks.

She doesn't eat throughout that entire time.

But 18 days later,

something is not right.

The female blows out her young before they're fully ready to emerge.

And they are followed by young cuckoo catfish...

...three times the size of her own babies.

She may have as many as six of them in her mouth.

And now

they begin to eat the cichlic babies.

The female cichlic treats the baby catfish as if they were hers.

They are truly cuckoos among fish!

The forces that created the Great Rift Valley

continue to shape Africa's landscape

even today.

At weak spots in the Earth's crust, molten rock continues to erupt.

There are some 200 volcanoes on the continent...

...many of them active.

They may bring destruction

but also, eventually, fertility.

This is Ol Doinyo Lengai.

For the past 400,000 years, ash from this great volcano

has fallen on the surrounding savannas of the Serengeti

and greatly enriched them.

This is the best grazing on the continent.

On it live the world's largest herds of migrating animals...

...and they, in turn, support predators.

Here, in Kenya, cheetahs have formed an unusual alliance.

These swiftest of cats usually hunt in groups of two or three.

But this team of five is one of the largest ever recorded.

Two sets of brothers

and a lead male.

They have now lived and hunted together for almost three years.

By teaming up, they can hold

the best territory in the area.

But, even so, with five mouths to feed, every hunt is very important.

They haven't eaten for three days.

To make a kill, they must get within 3 metres of their quarry

without being detected.

Thick cover.

That will help them.

Topi... nearly three times their size...

...and quite strong enough to fight off a lion,

let alone a single cheetah.

Now out in the open...

...every step the cheetahs take increases their chance of success.

The herd scatter, and the team splits up.

But they didn't get close enough.

They switch targets to zebra.

Everyone now knows that they're here.

They must devise a different approach.

All eyes are on the brothers.

Out in the open, they seem to be no threat.

But the lead male is missing.

The brothers are decoys.

The trap is set.

The other four now join the lead male.

Under the combined weight of five cheetah,

death comes quickly.

Today, Africa's savannas support larger herds of big game

than anywhere else in the world.

And they, one way or another,

provide food for all kinds of smaller creatures.

An oxpecker.

A resourceful little bird with an unusual diet.

Fleas, ticks and even dandruff are food,

as far as they are concerned.

Both parties benefit.

The oxpecker gets a good meal...

...and the host is cleaned in those places it could never reach for itself.

Each bird, every day, collects hundreds of ticks

and thousands of insect larvae.

But some oxpeckers go for rather riskier meals.

Hippopotamus are highly territorial and very aggressive...

...so oxpeckers tackling them must always be on their guard.

But there's much to be gained.

Blood is the most nutritious meal of all.

Pecking ensures that cuts remain open and blood keeps flowing.

And an oxpecker, once it's found an open wound,

will stay alongside it, no matter how much that irritates its host.

The reward? An endless supply of food,

whatever the conditions.

Not all of Africa is rich and fertile.

A third of the continent is desert.

This is the Namib in the southwest.

At its heart, a disused diamond mine

that was abandoned nearly 70 years ago.

But it still has one inhabitant.

A desert specialist...

...and one of Africa's rarest predators.

The brown hyena.

This ghost town is her home.

Its ruins give her valuable protection from the elements.

She has been here for 15 years.

She's already reared nine generations of cubs.

These two youngsters have reached a critical stage in their lives.

They're four months old, and now they need regular solid food.

But there is nothing edible in these ruins,

so their mother has to look elsewhere

and may leave them for several days on end.

Brown hyenas may walk over 20 miles a day in search of food.

This is some of the most hostile country on the planet.

Temperatures reach a blistering 5 degrees Celsius.

Strong winds blow incessantly.

Hyenas from all over the Namibia head for where the sand dunes meet the sea.

Somewhere along

this seemingly barren stretch of sand,

there is food in great quantity.

Cape fur seals.

There are around 10,000 of them here.

Adult seals are large and strong.

But their pups are neither.

The youngsters are closely guarded by their mothers.

A hyena, however, knows to be patient.

Sooner or later, seal mothers must return to the ocean to cool off.

A single seal pup could feed a hyena and her family for days.

But finding food is only half the battle.

It now has to be carried back.

Jackal is here too...

...and it's not alone.

If a hyena loses her kill, she'll have nothing with which to feed her cubs.

The jackals won't follow her very far from the coast.

It's too hot for them in the desert interior.

Only by making these long journeys

can brown hyenas manage to survive in the middle of the Namib.

But some desert animals seldom move far.

The Kalahari Desert.

Here, food is more plentiful...

...but it's hidden.

A pangolin.

She can collect food that others can't reach.

A keen sense of smell enables her to detect

the presence of ants and termites in their nests beneath the sand.

Her sticky tongue, some 30cm long,

enables her to collect them from deep underground.

And she's being carefully watched.

The drier it gets, the deeper the termites live.

Many are way beyond the reach of even a pangolin.

But not of an aardvark.

It's the world's largest burrowing animal.

Its sense of smell is extremely acute.

Shovel-like claws and powerful legs enable it to dig down

to depths of five or six metres.

A full-grown aardvark needs to eat about 50,000 termites every day.

Termites are highly nutritious and full of moisture,

and they can be collected here year round.

Aardvark are usually nocturnal.

But the fact that this one is foraging in daylight

is a sign that food is scarce.

Recent droughts in the Kalahari have led to low termite numbers

and, as a consequence, aardvarks here are close to starvation.

Changes in the world's climate are affecting many of Africa's animals.

It's predicted that in the next century,

Southern Africa will warm twice as much as the global average.

The future will be bleak for those that cannot adapt fast enough.

In Zimbabwe, it hasn't rained in six months.

During a drought, food becomes harder and harder to find.

Apple-ring acacias produce pods that are full of protein...

...but mostly on their higher branches.

Six metres up, they're out of reach

even for the continent's largest animals.

This bull elephant needs to eat about 90kg of vegetation every day.

He's worked out a remarkable way of surviving

in these lean times.

But it requires great physical strength.

Only a handful of bulls have mastered the skill.

He weighs over five tonnes.

This is a truly monumental effort.

Those around him benefit too.

Elephants have used their great intelligence to help them survive

Africa's driest times for millennia.

But today, they face an even greater threat.

It's thought that as many as 20 million elephants once roamed the continent,

but many have been killed for their tusks...

...their ivory used for entirely ornamental purposes.

Now just 350,000 elephants remain.

These stockpiles of confiscated tusks

represent half of the elephants killed on the continent

in just one year.

But of all of Africa's remaining wildlife,

it is the rhinoceros that has been most affected by poaching.

In the Far East, its horn is used as traditional medicine.

All of Africa's rhinos are now under threat...

...but for one subspecies, it's likely to be already too late.

The northern white rhinoceros is facing extinction.

Scientists are working on a solution,

but no male now survives, so natural breeding is impossible.

These two females are the last of their kind.

When they die,

an entire subspecies that inhabited the Earth for millions of years

will have disappeared for ever.

Right across Africa,

human beings are having a devastating impact on all wildlife.

Cheetah numbers are decreasing

year on year.

Today, there are fewer than 8,000 left on the continent.

The global demand for pangolin scales for use in traditional medicine

has now made them the most trafficked animal on the planet.

And western chimpanzees are so threatened by the loss of their habitat

that they are now critically endangered.

In this female's lifetime,

three-quarters of the forest in the Ivory Coast

has been felled for plantations.

Deforestation... and not only in Africa...

continues on an enormous scale.

64 million acres of forest are destroyed every year

to make way for agriculture and industry.

An area of forest the size of a football field

is disappearing every second.

Climate change is affecting global weather patterns.

Rainfall is increasingly unpredictable.

Average temperatures are soaring all over the globe.

Extreme weather is now affecting wildlife

on all seven of the planet's continents.

Today, scientists tell us that we are at the start of a mass extinction,

and one that is being caused by human activity.

Over a million species could be wiped out,

many within the next few decades.

But with help, even the most vulnerable wildlife populations can still recover.

In Africa's Virunga National Park,

an intensive conservation programme for the mountain gorilla

has raised their numbers above 1,000 for the first time since records began.

And in Antarctica,

the international ban on whaling has meant that the great whales

have returned to the Southern Ocean in numbers not seen for a century.

So we can improve things...

...if we determine to do so.

This is a crucial moment in time.

The decisions we take now

will influence the future of animals, humanity,

and indeed all life on Earth.

For the Africa team, each shoot presented its own challenge...

...but one tested them in ways they never imagined.

The team journeyed for six days to the heart of the Congo rainforest.

Their aim... to film the intimate lives of lowland gorillas.

They worked with local expert trackers,

who can pick up the trail of evidence left by the gorillas.

From the plant, they can tell which way the group has gone.

As they close in, the team wear masks to stop the spread of disease.

Finally, a silverback and his family in the trees.

Look at that big boy.

He's huge!

You don't want to look him in the eye because that...

Oh, OK!

The trackers have known this male for 20 years

and use clicking noises to reassure him.

It was a completely amazing experience.

Just came closer and closer and closer,

and my eyes got wider and wider and wider.

Yeah, it was incredible. I'm just sort of smiling.

It's kind of hard to process.

But soon, the gorillas head into the thickest jungle...

Heavy, heavy.

...which means that keeping up is difficult.

There are a group of gorillas somewhere in this mass of vegetation

but it takes us about ten minutes just to cut a few-metres path through it.

Filming them is virtually impossible.

Oh, there's always a piece of vegetation in the way.

Oh, God, I can barely see anything.

As the days pass, the jungle begins to take its toll.

Oh, God, this is awful.

Your ears, your nose, my eyes... They're flying everywhere.

And with little filmed, the reality of the situation is sinking in.

It's going to be a real challenge for me to get a sequence here,

and it's a long way to come to get nothing.

Yeah, I'd say I'm feeling the pressure at the moment.

Half the shoot is now over,

so the crew decide to move to a more open area.

Their destination...

a clearing known as a bai.

So, our luxurious home for the next ten days or so is the top of this mirador.

It's a little cramped, but from this platform

they hope to spot the gorillas emerging from the forest.

On their first morning, the crew awaken to a visitor.

It's our first elephant on this trip.

There's a big bull in the middle of the bai..

And finally,

the risk of moving pays off.

It's been a really, really quiet morning,

but a big group of gorillas, about 15,

has suddenly appeared really, really close to us and, apparently,

this very rarely happens. Maybe about once a month they'll come this close.

Over the next week, the gorillas continue to visit the bai...

Until one afternoon...

...gunshots.

On the platform, the team are vulnerable.

There's been poachers probably within eye shot of us.

They know we're here. We can't see them.

And two big gunshots.

They decide to evacuate.

But there's also a risk of walking through the jungle at night.

The one rule of the forest is not to walk in the forest when it gets dark,

so we're going as fast as we can.

Elephants are in the area, so this is extremely dangerous.

An hour later, the team reach a camp.

Oh, God.

That is not an experience I'd want to repeat again.

We had to choose between the risk

of getting charged by an elephant in the dark

or getting shot by poachers.

Um...

So, yeah, it's... pretty stressful.

I'm going to have a sit down.

If they're ivory poachers, this is quite serious,

and they've got nothing to lose,

and the gunshot was aimed in our direction, that's where the sound was.

It's a pretty scary situation to be in.

Overnight, an armed anti-poaching unit is called in to scout the area.

Because of the remoteness of this park,

there's been no poaching recorded in the last 20 years,

so this is a really significant moment and it's a really sad moment,

because it means that, as roads are being built here,

it's becoming less and less remote, the animals here are in more and more danger.

Within a few hours, the anti-poaching unit return

with a stash of tusks and news of a slaughtered elephant.

It's about as tragic as it gets, really, and we heard the two shots go off,

so we were there when it happened and the elephant went down.

With the armed poachers still on the run,

the team decide to abandon the shoot.

It's really tough leaving on such a sad note.

We've been watching these elephants in the bai.. for the last week,

and knowing that one of them was killed yesterday is, um,

is horrible and, yeah, it's sad to be leaving like this.

The poachers were caught, but this incident

is a reminder of how vulnerable wildlife has become on the continent.

Even animals in the remotest parts of Africa,

and indeed all our seven worlds,

are now at risk.