All language subtitles for Waterhole Africas Animal Oasis 1080p BBC

In the baking heat of the
African savannah...

..as rivers dry up...

..animals flock to the waterhole.

But we've never fully understood

how a single water source can
support so many competing species.

So we're doing something
ground-breaking.

Welcome to Tanzania and to the
Mwiba Wildlife Reserve

and to this unique waterhole
behind us.

We are working with the reserve
to create the world's first

waterhole with a built-in
specialist camera system.

This waterhole has a half-submerged
filming hide right in the middle,

and it's rigged with
remote cameras so we can see

every angle of animal behaviour
like never before.

GIRAFFE GRUNTS

It's a unique chance to follow
the evolution of a waterhole

ecosystem and the lives
of the animals that depend

on it, from the very beginning.

This is our first visit from a lion.

We don't know who will turn up
and in what number...

..but we want to observe and record
every single species...

..over a period of six months.

We're filming from the start
of the life-sapping dry season

when water is scarce
and tempers fray.

That's not a happy elephant.

Until the pressure finally breaks...

THUNDER CRACKS

..and the annual rains
change everything.

From up here, you get a great view
of an ecosystem.

We'll follow the fight for survival
at the one place all animals gather.

Everything changed when the
predators turned up.

This is the story of life...

ELEPHANT TRUMPETS

..and death at the waterhole.

In East Africa, Tanzania,

south of the Serengeti ecosystem

is a protected area spanning
53,000 hectares.

Mwiba Wildlife Reserve.

It's a safe haven for Africa's most
iconic species,

including elephant...

..hippo...

..giraffe...

..leopard...

..and lion.

But in our changing world,

this region faces a growing
shortage of water.

Look at it, so green, fresh,
verdant.

That said, in a couple of
months' time, all of this

will be parched and brown.

All of these tiny little pools
of water will be gone.

And the wildlife here is going
to be struggling to survive.

For half the year in 2018,

there was just nine millimetres
of rain.

Well below average for Tanzania.

And with the growing impact
of climate change,

life here is set to get tougher.

Temperatures in Africa are rising.

In just 30 years, it's predicted
the continent will endure 50%

more warming than the rest
of the planet.

As a result, many natural
water sources are drying up.

Let's just call this digger in.

To give its wildlife a much-needed
lifeline, Mwiba Reserve has decided

to build a waterhole
on an open patch of grassland,

easily accessible from all
directions.

Natural waterholes appear after
rains deep in the savannah,

but they're quickly populated by
wildlife and often dry up fast.

So this is a unique opportunity
for us to work with Mwiba and study

a waterhole built from scratch.

Look at that!

It's very exciting, isn't it?

We want to find out how hundreds
of different species find,

use and interact around a new
water source.

Wow. OK. Now, I measure about...

I don't measure about anything.

I'm 1.83 metres
and I'm still above this.

We ideally, I think, we want about

two metres depth at our deepest
point.

But what's essential is going
to be the slope like this,

because a lot of animals are not
going to literally go in.

That's going to be our wallowers -
our, you know, elephant,

our buffalo, our warthog.

I think many of the ungulates
are going to come to the edge here,

stand on that edge and sip.

And certainly all of the bathing

animals are going to be in this
zone, so the shallow part of the

waterhole is going to be
equally important.

It's going to be fascinating.

I honestly think that we're going
to see an enormous diversity

of species coming to this waterhole.

To uncover the secret world
of the waterhole, we're bringing in

a weatherproofed remote camera
system,

able to record day and night.

To help make it
wildlife tamper-proof,

we dig two-metre-deep trenches...

..excavating over 100 tonnes
of soil for 4km

of fibre-optic cable.

60,000 litres of water
fill two separate pools,

giving more access points
for thirsty animals.

This is a project on a grand scale.

It's bigger than any of the other
waterholes that are currently

here at the end of the wet season -
they're just puddles.

This is going to be a pool
of some significance.

We are going to film here at three
of the most critical times of year

for local wildlife.

From the middle of the tough
dry season.

Then, a couple of months later,
when temperatures soar into the 40s

at the hottest time of year.

And finally, at the height
of the first rains.

Now, it's the middle of the
dry season.

20 cameras are set to record

every detail of life
for the next two weeks.

They are remote controlled
from our base camp,

where biologist Ella Al-Shamahi

and I can watch them live
and play back footage.

We've got our team monitoring
these cameras 24/7.

Those strange triangular structures,
those are so that the elephants

hopefully won't step on the cameras
and damage them.

As Ella says, it's 24/7, we're
watching them throughout the course

of the day and the night
using infrared.

And, of course, we're also watching
this waterhole from the air.

We've got a drone up at the moment.

And there you can see from mission
control, it's about 200 metres

across this parched grassland
down to our waterhole complex here.

A tunnel leads into our hides
so that we can sneak in

without the animals seeing us.

And we've got the two pools
either side here.

For our first two-week filming
window, I will be attempting

to collate data for every visitor
and create a species list

so we can track how many animals
come to a new waterhole.

Chris will be reviewing footage
to analyse the complex animal

behaviour behind every interaction.

Our first question - how long
does it take wildlife to find

a new waterhole?

The answer - 45 minutes.

WARTHOG GRUNTS

Here, top right, we've got warthog.

Wow, that's awesome. Yeah.

It's a whole family there.

Mwiba wildlife expert
Eugene Raymond joins us to review

the footage, to offer some
local insight

into our waterhole pioneers.

We've seen these in
and around Mwiba area,

and it's one that's got a very
interesting story

cos the mama died and then

the four little ones managed
to get to this level.

So you've seen them growing up?
Yeah, I've seen them growing up.

These warthog orphans live
250 metres away.

They probably discovered the
waterhole whilst foraging for food,

but, interestingly, they're not
here to drink.

What they really need...

..is mud!

It's a stifling 35 Celsius,

but warthogs don't have sweat glands

that regulate their body
temperature...

..so they must use mud
to cool themselves down.

Our camera rig includes a
specialist thermal camera,

which reveals how effective
this behaviour is.

The warthogs' bodies turn blue
as their temperature decreases.

Mud bathing can reduce their body
temperature

by a life-saving 3.6 Celsius.

The warthogs weren't on their own
for very long.

Look, the warthogs scarper as soon
as the elephant arrives.

ELEPHANT TRUMPETS

They would normally give respect
for this big beast to come in

and get some water.

What's interesting is that they have
the capacity to smell water.

Ah, yes, that's very true.
Absolutely.

What, 15 miles away at least,
I imagine.

I believe they have incredible
ability to do it even

farther than that. Further than
15 miles? Yeah, for sure.

It's not really that much
of a surprise, then,

that they would be amongst
the first to turn up.

So here's another one.
That's another male.

Do you know this elephant?

Oh, that's a young bull
that I know, for sure. Yeah.

You see the right tusk is shorter
than the left tusk.

If you look at one tusk
that is shorter than the other,

then you get to know...

This elephant is either
right-handed or left-handed.

The guides call this elephant Nusu,
which in Swahili means "half".

And his companion is Ndogo,
which translates as "small"

because he has short tusks.

An African elephant needs to drink
nearly a bathtub of water each day.

They may have to walk up to
195km to find enough.

We've made elephants happy by giving
them fresh, clean water.

It's not often you get to make,
you know, megafauna happy.

Especially in the dry season.

Elephants are thought to help

other animals locate water
in the dry season.

As they forage, the two males
inadvertently create pathways

through the bush leading
directly to the waterhole.

This area is home to lions,
leopards and giraffes.

We know they're out there,
but we don't know

when and if they'll turn up
to the waterhole.

And you've got to remember
that up until fairly recently,

this waterhole simply wasn't here.

15 minutes after the elephants,
more new species arrive.

And by reviewing the footage
from day one, we discover

how different animals approach
a new water source.

Ella! Ella.

Got impala that have come in.

Waterholes are dangerous places
for impala, as big cats often hunt

them when they come to drink.

I mean, they are extremely nervous.

They're essentially a
forest antelope,

so coming into the open like this
is a perilous exercise.

Impala aren't the only species
that are wary at the new waterhole.

Now we have zebras.

The first zebra also approach
with caution, but there's a theory

that suggests they have some natural
protection from predators.

I don't think there's a definitive
answer, but do you know why the

zebra's got stripes?

I'm assuming it's some kind of
a camouflage thing.

I was looking at some work
relatively recently that shows

that when you get a large herd
of zebra moving,

the way that their bodies move
cycles the stripes

and visually is disorientating.

It forms an optical illusion,
which generates an enormous amount

of confusion in terms of the
visual capabilities

of any pursuing predator. Really?

It's confusion colouration.

That's interesting. Hm.

To add four species to our list
on day one, within just a few hours

of the waterhole being finished,

shows just how harsh
the dry season is.

50 metres away, the nearest water
source in the area,

the Arugusinyai River,
is completely dry.

And for herbivores, it's not
just water that is in short supply.

Look at it, it's absolutely parched.

Imagine trying to eke a living,
eating something like this.

I mean, there must be
nutrients there,

but trying to firstly digest it
and then process it...

Thankfully, there is some evergreen
foliage left here.

This acacia, look at this.

Looks relatively lush and green,

but it comes with a cost - protected
by these vicious spikes, of course.

Again, not all of those herbivores

are going to be able to nibble this.

And then lastly, there is something
that makes this environment very,

very hostile at this time of year,

not just for all of those animals,
but for us, too.

And it lurks...here.

Look at that, almost bumped into it.

You see this little brown smudge

in the crook of the grass here?

That is a solid mass of ticks.

They call them pepper ticks at
this stage because they're so small,

they're about the size of a
ground piece of pepper.

And any animal that brushes into
this grass here is coated.

They get under the skin
and they start to suck its blood.

At this time of year,

this part of Tanzania is a
tough place to be wildlife.

At night there is some relief,
as temperatures drop to 15 Celsius.

But this is often the most dangerous
time to be at a waterhole.

Lions, leopards and hyena
are more active after dark.

Our specialist camera system
switches to infrared light...

..so we can watch the waterhole
for nocturnal predators.

And on the first night,
just before 8pm,

the cameras catch one of
Mwiba Reserve's most elusive

and powerful hunters.

Leopards have the largest ranges
of any big cat.

Males can range over
2,000 square kilometres.

It's not clear if this male
is a Mwiba resident

or just passing through.

LEOPARD GROWLS SOFTLY

We collate all the camera footage.

THUNDER RUMBLES

Wow. Oh, look at the elegance.

And expert guide Eugene joins us

again to review the shots in order
to identify him.

It's probably one of the leopard
that I know in the area.

We've named him Jasiri.
And what does that mean?

Jasiri is a Swahili word
and it means "brave".

He's not very skittish,
he's quite relaxed.

Those rosettes are unique to
every leopard.

Every leopard has a unique
spot pattern.

Those markings on the whiskers,
up to the nose on the side,

these are the ones that will tell
you which one it is.

They will never be the same.

Jasiri's arrival is a sign that our
new waterhole is beginning to get

the attention of Mwiba's carnivores.

Leopards hunt a wide variety
of prey, feeding on everything

from insects to rodents
to large antelopes.

The waterhole could be a new
important hunting ground for Jasiri.

So what do we think? Do we think
he's already had a kill?

He's probably got a kill somewhere
and put the kill up a tree.

Look at his neck, the muscles
in the neck and that gives them

the power of getting up, carrying
stuff, heavy stuff,

pretty much the same size,
and they will take it up a tree.

Because they are in so many
competitions with other predators

like hyenas, lions,

and they would come for a drink

and go back on their same spot
at the kill.

It doesn't need water
every single day.

They get it in two ways.

They get it from the body fluids
that they take out of the animal.

And then they also,
when they're digesting it,

they produce metabolic water.

So in the process of digesting
that food, the hydrogen teams up

with the oxygen and produces
water and that can provide them

with up to 10% of the water
that they need.

And that's the difference
between dying of thirst

and not dying of thirst.

So it's really important
for these types of animal,

that metabolic water.

What a view, and what an animal.

Mwiba Reserve is home to lions
and spotted hyena,

but Jasiri the leopard beats them
to be the first apex predator

on our species list.

After his visit, the night is quiet
at the waterhole.

But the silence doesn't last long.

BUFFALO GRUNT

At 7.30 on the second morning,

the biggest herd of animals
comes for a drink.

80 Cape buffalo.

If we go to this camera over here,

can we take a closer look at them
on the ground?

BUFFALO GRUNT

They're an enormously robust
and powerful animal.

The males weigh up to a tonne.

Their horns grow to a metre
across, fused in the middle.

They're very much front-heavy,
massive fore-limbs.

Look at that, you can see the

pulsing throat of a buffalo.

Some of the species that we have
here don't need to drink every day,

but buffalo like to drink every day

and they drink an enormous
quantity of water.

That's the equivalent of a
nice cold pint of lager

at the end of a very hot afternoon.

Look at the look of satisfaction
on that buffalo's face.

Well, maybe I'm pushing
the anthropomorphism there

a little bit, but I can imagine
it's a happy buffalo.

The waterhole is a lifeline
to water-dependent animals

like Cape buffalo.

This herd can drink up to
3,000 litres in just one visit.

And the buffalo
aren't travelling alone.

Oxpeckers provide an
invaluable service

to buffalo in the dry season.

And in return,

they get a free ride to water
and all the food they can eat.

They're on there removing parasites,

plenty of ticks here at this
time of year.

Ooh, straight...straight in!

And, look, right inside the ear,

and you can see where there's less
hair in there, how it will be easier

for the ticks to attach.

Look at that, it's feeding
furiously.

So we can't see them,
but undoubtedly, this oxpecker can.

CHRIS LAUGHS

Can't imagine what it must be like
to be the buffalo with a bird

right inside your ear.

But, clearly, it is happy

with that compromise because

this bird is feasting on

those parasites which are
inside that ear.

Love that! Little cameo of natural
history that we're able to see

because we've got these
extraordinary cameras

and we're so close to these animals.

Over the next few days we add
an incredible 40 new species

to our list.

Including four birds.

Yellow-billed storks often hunt
in shallow water.

Black-faced sandgrouse come
to waterholes not only to drink,

but to wet their breast feathers

to carry water back to their chicks.

Cape turtle doves are found
across southern Africa.

Bare-faced go-aways.

The species get their name from
their distinctive call,

which sounds like, "Go away."

GO-AWAY CALLS OUT

African hare hop in.

Water helps them digest vegetation.

On night three,

a lone waterbuck that needs water

daily to survive,

comes for a drink.

Two species of primates also find
the waterhole -

olive baboons and vervet monkeys.

They like to socialise around
water sources,

much to the annoyance
of some of our residents.

SQUAWKING, CHATTERING

By day five, the list has grown
to 20 species.

We are also seeing the same animals
returning every day.

Our cameras have already recorded

nearly 200 hours of footage
combined.

And I'm seeing a pattern emerge.

We're actually starting to see

some really interesting data.

We're looking at which species

are turning up to the waterhole
at what time.

Some of these animals have
pretty much set times

and they're turning up
like clockwork.

There is already a schedule to life
at the waterhole.

From around 8am, a steady stream
of impala come for a drink.

11.00 is the most frequent time
for zebra.

ZEBRA SNORTS

Around 1pm, the very punctual
warthog orphans come to mud-bathe.

3pm is when elephants
often turn up.

ELEPHANT TRUMPETS

And the herd of buffalo are coming

first thing in the morning
and at dusk.

BUFFALO SNORT

I have a theory as to why
this routine has been set

so early on within this new
waterhole community.

There's certain patterns that
indicate survival strategies.

It's interesting that during
that midday sun, that real heat,

the place doesn't become deserted.

So some of the species that are most
vulnerable from predators,

they're willing to brave
that scorching heat

because if they turn up later
in the day,

that's when the predators are about.

The fear of predators is affecting
when animals come to the waterhole.

But that's not the only thing
the cameras are revealing.

After eight days, a hierarchy

is developing within the waterhole
community,

and by analysing footage,
we discover that one species

is trying to dominate.

What we've got is a waterbuck here,
and where we're seeing these come

to our waterhole, this male,
they're always coming on their own.

The buffalo approach...
So he was there first.

He has a look round...
Oh! He darts off, doesn't he?

He doesn't even bother to entertain
any thought of staying there

with a huge herd of buffalo.

They encircle the waterhole
and they basically just own

that very valuable resource.

We've got another bit as well.
Here we go.

So these small group of zebra
have come all the way round the side

of the pool to the other end

where they're hoping
to have a little sip.

But as you can see,
there's another buffalo.

Just wait to see what happens.

ZEBRA SCREECH

That's deliberate aggression,
isn't it?

The buffalo are completely
monopolising the area. Yeah.

OK. So the big boys have pushed out
the zebra,

but what happens when an even
bigger boy turns up?

ELEPHANT TRUMPETS

BUFFALO SNORT

ELEPHANT TRUMPETS

That's not a happy elephant.

The buffalo are not drinking,

notice, they've had to stop
drinking.

They're casually strolling
in both directions. Yeah.

They don't know where to go,
but they're definitely not drinking

and they realise that they're...
And look. Ooh!

Yeah. This is a frustrated,
frustrated elephant.

And it gets a little bit worse
because he comes round this side.

ELEPHANT SNORTS

This is a bit of displacement
behaviour, I think.

He's so cross with the buffalo,
he can't do much about them,

so he's kicking the ground, look,
still flaring his ears,

waving his trunk.

Both elephants and buffalo

came to the waterhole
in the first 48 hours.

They are our most regular
and heaviest drinkers.

And as the dry season intensifies,

they're encountering each other
much more often.

The buffalo have strength
in numbers,

but an elephant weighs
up to 6,000 kilos

and the buffalo aren't willing
to put up much of a fight...for now.

For these two giants, a changing
climate and a growing scarcity

of water has potentially
life-threatening consequences.

In the '90s, the number of buffalo
were decimated in the Serengeti,

and the Maasai Mara
because of drought.

So it's interesting to see that
behaviour that created

this dominant presence.

That's for very good reason,
I guess.

They really, really need
that water.

In 24 hours, we measure
that between them,

buffalo and elephant are drinking
over 7,000 litres of water.

A natural waterhole might dry up
with this level of demand.

But this one has a plumbed in
fresh water supply

that we can keep topping up.

It's been tremendously busy
at the waterhole overnight,

and as a consequence,
the water level has gone down,

quite significantly, by at least
two or three centimetres.

We are keeping track of water usage.

A centimetre drop in both pools

is approximately 2,000 litres
of water.

I'll just turn this tap on.

You can hear it bubbling away.

WATER GURGLES

This water is from a
naturally occurring reservoir

47 metres underground.

It's a sustainable water source

that's replenished every
rainy season.

Wind turbines power the pump,

which can deliver up to
12,000 litres per hour...

..should we need it.

Over the next couple of days,

the important role our waterhole

is starting to play in the region

is underlined by a staggering

20 new species that come
for a drink.

Including the hadada ibis,

which are native

to Sub-Saharan Africa.

The white-tailed mongoose,

which is the largest of the
mongoose species,

reaching one metre in length.

Kirk's dik-dik, one of the world's

smallest antelope,

standing at just 35cm tall.

And a black-backed jackal,

that wastes no time

marking this territory.

So far, 40 species have visited
the waterhole.

And on day ten, the tallest animals
on Earth come for a drink.

Extraordinary animals, giraffe,
absolutely extraordinary.

That looks like a terribly
uncomfortable position to be in,

to have to drink, but that's
the least of its problems.

The first thing is if you've got
your head all the way up here

on a very long, stout neck
and then you tip it down to drink

like this, all of the blood
would rush down into your brain

and you would presumably black out
straight away, but not the giraffe.

They've evolved something
called a rete -

it's a tight bundle of arteries.

So the blood does run down the neck,

but when it gets to this rete
at the base of the skull,

it slows it up so it doesn't
flood the brain.

And then equally, when they tip
their head back up again,

having had a drink, you would think
that all the blood would drain out

of the brain and they would
simply faint, but they don't.

They have valves in those
blood vessels which stop that blood

cascading back into their body.

They've also got very strong
oesophageal muscles.

I mean, look, it's now got to pump
the water all the way from its lips

up to its body.

We tip water into our mouths and use
gravity

to get it into our stomach.

This one's got a reverse gravity
and that's what they do,

they've got very powerful muscles
to suck that water up.

ELEPHANTS TRUMPET

It's only taken ten days for the
waterhole to look like

an established oasis
in Mwiba Reserve.

But on day 12, the area
goes eerily quiet.

To help discover where the animals
have gone...

..we've sent wildlife cameraman
and tracker, Bob Poole,

to investigate.

Less than 100 metres away, he spots
a potential reason

for the sudden quietness
at the waterhole.

Right there, that's a pretty
big animal, you see.

One, two, three, four, and the pad
going to here.

Look at that...look at that
distance in that.

It's definitely a big cat,

whether it's a lion or a big
leopard.

Look at the size of this here.

You see?

So you can tell this is a very fresh
track because you've got

a vehicle track here,

and right on top of that
is a big cat.

Chris. Chris, do you copy?

Hi, Bob.

Hey, I've just found some big cat
tracks on the road here.

Whereabouts are you relative
to the waterhole?

Yeah, we're only about 100 yards
away from you on the main track

to the north.
Must have been...

I would have to assume it had to be
early this morning.

I'd like to follow these tracks
and see where they go.

OK. Well, I'll see you a bit later.

While a predator is in the area,
only a handful of species will feel

safe at the waterhole, including
the largest land mammal on Earth.

Elephants are rarely predated
by big cats in Tanzania,

and this herd also has strength
in numbers.

Look at that!

Oh, my goodness. How many?
How many are we looking at?

OK, look. So that's eight adults.

One, two, three, four juveniles.

Look at that shot.

Look at the view we've got there.
That's amazing.

Look at the little youngster.

A herd of 12 makes this the
biggest number of elephants

at the waterhole so far.

Elephant herds are led by
a matriarch, who is identifiable

by being bigger and older
than the others.

This one is around 30 years old.

The youngest calf is just over
a year old.

Elephants are notoriously protective
of their young,

but this family are completely
at ease with our remote cameras.

And they're the first animals
to take a proper dip

in the waterhole.

But they're not just bathing -

they, like our warthog orphans,
need mud.

And this is what it's about with the
mud. They're chucking it on there,

it's going to evaporate the water
out of the mud.

What's interesting here, though,

is that the elephants have
very wrinkly skin. Yes.

So the mud goes into the wrinkles
and therefore it takes

longer to evaporate.

And this means that the cooling
process will go on longer

than if they had smooth skin.

But also, that wrinkly skin,

that increases the surface area
and it helps with heat loss.

And, interestingly, the
Asian elephants, of course,

don't have the same level
of wrinkles in their skin...

No, they don't. ..because these guys
need to cool down a bit more.

Mud can also act as sunscreen
for elephants,

but it is often in short supply
during the dry season,

which explains why this herd

is exploring every corner
of the waterhole.

Right now we've got a very expensive
camera very, very close...

SHE CHUCKLES

I know. ..to an elephant's feet.
Great. Yeah.

Oh. Oh! It's...it's destroyed
the camera!

SHE LAUGHS
There goes the camera.

And immediately, we can switch
to another one.

Look at that.
ELEPHANT TRUMPETS

Oh, they're having fun, aren't they?

Oh, the calves are having
a great time.

CALF HOOTS

There's a serious side to
all this play.

This calf needs to get to grips
with trunk control.

There are 40,000 muscles in an
elephant trunk and it can take

calves over a year to master.

It's a vital skill, especially
during the dry season

when water and mud are scarce.

It's interesting that they've
come out of the mud...

..and now they're actively covering
themselves in dust.

It's from one extreme to another,
isn't it?

So this dust bathing, have you ever
seen this before?

Yeah, I've seen them dust bathing...
But after. ..but not...

No, not immediately after they've
been made mud bathing, you know.

Potentially might be
seeing different cultures here.

We know the same species in
different parts of a country

will exhibit different cultures,
just like we do. Yeah.

So this might be something that's
a bit more unique. A peculiar habit

to this little group.

They get sticky and then
they get dry.

They've started to move off,
haven't they?

Can we see camera six?

The remains of camera six.

Look at the destruction of that!

It's still working, it's just
a but dirty. It's worth it.

I mean, I'm not paying the bill,
but from my point of view,

that shot was sensational.

After the elephant family leave,

the waterhole goes quiet again.

Bob is still following the big cat
prints that are just 100 metres away

from the waterhole, but the trail
has gone cold.

From now on, he'll have to rely
on his tracking skills.

The guineafowls' alarm calling
over there sounds like,

"Gah! Geh-geh-geh-geh-geh-geh!"

They give away predators
all the time.

Perhaps there's a lion or a leopard
right in this bush.

That noise right there -
"Gah! Geh-geh-geh-geh-geh-geh!"

It's an alarm call.

GUINEAFOWL CALL OUT

Guineafowl are a ground-dwelling
bird found across Africa.

They're known for being highly vocal
when there are predators about.

Might go up there and see what
they're cackling at.

WHISPERS: There's a lion
right there.

There's a big lion right there,
do you see it?

At the base of the tree right there.

Wow. We found it.

He's just waking up from a
long day's sleep.

LION GROWLS SOFTLY
He's huge.

He's wearing a collar
so he's obviously being studied.

But he's a seriously big lion.

Tanzania is home to nearly half
of all wild lions on Earth...

..with approximately 11,500
spread across the country.

Males are not always part of a
pride, so this large lion

could be travelling alone.

It's likely that he's noticed
the increased prey activity

at the new waterhole.

In the dry season like this,

wildlife gets concentrated around
water points

and that makes it easier for lions

because they can ambush
those water points.

And so that gives lions
an advantage.

It's a good chance that this guy
has shown up over here

because there's water nearby.

Here he comes.

Wow, that is a big lion.

And he's headed in the direction
of the waterhole.

Sure enough, just after midnight,

the lion arrives at the waterhole.

By roaring...
MUFFLED LION ROAR

..this male is claiming
his territory.

The surrounding trees provide
the perfect hiding place

for this ambush predator.

To find out more about this lion,

we're enlisting the help of
Nuhu Mhapa,

one of Mwiba's top guides,

who's familiar with all of the
big cats in the area.

I think I know this guy.

He's...he's called Kalumass,

and he hasn't been here
for quite long.

It's just amazing that he has just
come back.

How do you recognise him?
Just from the size.

This is definitely Kalumass.

At over 250 kilos, Kalumass is one
of the largest lions in Tanzania.

He's such a unique individual.

Scientists from the
Tanzania Wildlife Research Institute

have been tracking his movements
for the past two years.

What do you know about him?

Do you know how old he is and where
he's come from, where he's been?

He was together with a pride of

four females, together with babies,
with the cubs.

That was in 2017, right.

From there he disappeared and left
the rest of the pride in the area.

He left the females and the cubs?
Yeah, and the cubs.

There was no other male involved?
No, no, no, no.

So he kind of abandoned them.
Yep, yep.

That's quite odd, isn't it?
That's what he did.

So he left them behind and
he disappeared.

And then we got a call from our
friends in Ngorongoro

and they said, "Hey, you know what?
Kalumass is here."

He's gone all the way to Ngorongoro?
All the way to Ngorongoro.

For the past year, Kalumass's
tracking data shows

he's been in the Ngorongoro Crater
area,

a neighbouring reserve teeming
with wildlife.

But now, this unusual male lion

has chosen to make a huge migration

to Mwiba, walking over 80km.

We think he's about nine years
old... Well, that's prime.

But, again, it's very impressive
to see such a lion that age

and he's still being highly nomadic
like this.

Which is, I mean,
is quite extraordinary.

At some point, this lion's going to
have to settle down! Well...

THEY LAUGH

He's getting on a bit.

Look, who's he got
to contend with here?

OK. We've got these two males
that just came in about

four months ago and they have

already met with the resident female
here.

Well, he's an impressive animal,
so they're going to have a

comeuppance when they meet him,
aren't they? Absolutely.

It takes courage for whoever
will see him to hold their ground.

Wow. It's going to be interesting
to see what happens. Absolutely.

What does Kalumass mean?

Kalumass means "sneaky". Sneaky boy.

Sneaky boy? Yeah, sneaky boy.

CHRIS LAUGHS
It's a fitting name - sneaky boy.

Yeah, he is a sneaky boy.

So, Kalumass has entered the
territory of the Mwiba pride.

What do we know about them?

Well, we know there are a couple
of males and a female,

and that she might have given birth
in the last month.

No-one's seen any of those cubs yet.

But if that is the case,
they're likely to be more protective

than ever of those cubs
and this area.

Now, the den is not too far away
from the waterhole,

so Bob has gone up there to see
if Kalumass

made it to the den last night.

The Mwiba pride den is just over
3km from the waterhole,

a distance Kalumass the lion
could have covered in half an hour.

On the way to the den,
Bob spots lions in the bushes.

There they are,

two male lions.

Wow.

I've probably just had a run-in
with Kalumass.

I think I see a little bit of a scar
on one of their eyes,

which makes sense because they would
really be defending their cubs.

Kalumass would kill them instantly.

There's a female. One of these two
is probably the dad.

Kalumass is a great big male and
he's formidable, even on his own.

But these two guys certainly
would overpower him,

but it could have been quite
a fight and they look

like they've had a rough night.

Kalumass may have been chased away,

but I'm discovering that his
presence seems to have altered

the routine of the waterhole
community

that has built up over
the past 13 days.

Everything changed when the lion
turned up.

You can see a shift in that
schedule.

So we're noticing that some species
are coming together.

So, for example, we're seeing the
giraffe, the impala and the zebra

turning up together.

Now, that's partly protection
in numbers, but there's something

really fascinating going on here,
and it's that they're relying on

each other's strengths to identify
the predators in the area.

Now, all of those three species rely
upon their eyesight, but of course,

the giraffes can see the landscape
much better.

And so those other two species are
relying on those giraffes to ID

the predators, and that's
why they're turning up

to the waterhole together.

Giraffe vision is so acute,

they can see movement from 2km away.

They are a life-saving early warning
system for other animals.

The waterhole is getting busy
again...

..and we're seeing more new
bird species...

BIRD COOS

..including Fischer's lovebirds,
that are only found in Tanzania.

Marabou storks, which are the
largest stork species,

reaching up to 1.5 metres tall.

Colourful lilac-breasted rollers.

They symbolise peace in many
African tribes.

And our first bird of prey -

an augur buzzard.

They often scope out waterholes

and predate on rodents and small
birds that come to drink.

Adding the augur buzzard brings
the species list to 61.

On average, we've had four new
species a day come for a

life-saving drink in the dry season.

And despite predators being
a constant threat,

there hasn't been any sign of
hunting at the waterhole.

But just 3km away,
Bob makes an ominous discovery.

I've just found this male kudu
carcass in the drainage right here.

This riverbed runs around
the waterhole.

It looks like predators are
picking off prey as they travel

to and from it.

So interesting, because it's just
been killed.

You can see the stomach
has been opened.

Whatever killed this kudu

is probably going to come back
to eat it,

so Bob is going to stake out
the carcass.

After four hours of waiting,

Bob spots something moving in
the bushes.

My goodness, that's incredible.

Wow, what a powerful animal.

It's the Mwiba pride lioness
that's made the kill.

The males are nowhere to be seen,

but this meal isn't all for her.

Whoa! Look at that, look at that

right over there on left side of
the screen.

Cubs coming down the bank.

Whoa.

That's incredible. Look at that.

I haven't seen any other lionesses.

So it means she's all alone,
at least as far as I can tell.

Lion prides vary in size,

but usually have up to a
dozen females.

A lone mother like this is highly
unusual,

especially with two cubs that are
just six weeks old.

That's a really tough thing
for a lioness to be all alone

like that with two cubs.

Very difficult for her
moving forward.

Only about 50% of the cubs make it
when their mother's alone like this.

The waterhole could become
a very important focal point

for this lone mother, as it provides
a reliable and potentially

easy source of food and water.

It's been 14 days since the
waterhole was built.

The species list is now up to 70.

There are still new animals coming,

but you have to look harder
to find them.

I've spotted a direct physical
relationship between our HQ here

and the waterhole all the way
down there, 200 metres away,

and it's in the form of mud.

Look up here in the apex
of the tent.

This is the nest of a
parasitic wasp,

and it's made this little
muddy chamber.

This is it. She's come in.
Look at this.

Look at that! Now, what an insect.

Now, typically, they like to hunt
caterpillars.

She'll sting it and paralyse it -

critically, not kill it -

and entomb it in that mud nest
whilst it's still alive.

Then she'll lay an egg on it,
then she'll go and catch another.

And when the nest is filled,
she'll plug that little hole

and those eggs will hatch.

And they'll eat the non-essential
organs first, thus keeping

them alive - fresh meat, you see -

and then they'll pupate
and hatch out.

I've got to tell you, these are
insect super predators.

And the thing is, she's only able
to do this because of our waterhole,

because you can't make a nest
like that without water,

cos you need top-quality mud.

So we provided a resource
for elephants, buffalo,

all of those birds and also some
really smart insects as well.

The parasitic wasp takes
the species list to new highs.

We're currently at 71,
and the interesting thing is,

it's a wide variety of species.

You've got small birds,
all the way up to

the great African elephant and
they're all here sharing this water.

But already that's really
impressive,

and it will be really interesting
to see how that number shifts

as the seasons progress.

In just two weeks,
a fully-functioning ecosystem

has sprung up at our waterhole.

ELEPHANT TRUMPETS

From butterflies to buffalo

and lapwings to lions...

..we've seen a wild community
build from nothing.

ZEBRA SNORTS

But their lives
are going to get tougher.

In two months, this corner
of Tanzania enters

the hottest time of year.

We'll be back to follow our
waterhole animals for

two critical weeks when the heat
is at its peak.

Next time... Temperatures surpass
40 Celsius.

Tensions reach boiling point when
a new predator swarms the waterhole.

Hyenas take over and invade
our camp.

There's a trail of footprints right
down to the opening of my tent.

The species list expands with an
unexpected African giant.

To think that we could have made
a home for a hippo.

Now, come on, I'd put that on my CV!

And for one extraordinary elephant,

the waterhole becomes
a vital lifeline.

That's a severed trunk. It's amazing
that he's still surviving.

In the baking heat
of the African savanna...

..as rivers dry up...

..all animals flock
to the water hole.

We've never fully understood

how a single water source can
support so many competing species...

..so we're doing something
ground-breaking.

Welcome to Tanzania and to
the Mwiba Wildlife Reserve

and to this unique
water hole behind us.

We are working with the reserve to
create the world's first water hole

with a built-in specialist
camera system.

This water hole has a half-submerged
filming hide

right in the middle, and it's rigged
with remote cameras

so we can see every angle of animal
behaviour like never before.

Last time, in the peak
of the dry season,

our cameras captured

over 70 species.

Look at that! Extraordinary animals.

This emerging ecosystem quickly saw

wildlife working together
in surprising ways.

They're relying on
each other's strengths

to identify the predators
in the area.

Now we're entering the hottest time
of year, when temperatures soar

to an unbearable 40 degrees.

Turning the water hole
into a lifeline

for the reserve's most vulnerable...

That's a severed trunk. It is
amazing that it's still surviving.

..and making this precious water
source a target

for a clan of notorious predators.

They must be just out here.

I can't see them.
It's completely black.

This is the story of life
and death at the water hole.

We built our water hole
in Mwiba Wildlife Reserve...

..south of the Serengeti,
500km from the east coast

of Africa in Tanzania.

This is a safe haven for Africa's
most iconic species.

The long, dry season is drawing
to a close, and we've returned

for two critical weeks
at the hottest time of year...

..when water is an even
more essential resource.

After five months
of crippling drought,

food is also in short supply.

The grasses have died off
and acacia trees are almost bare.

The water hole is more vital
than ever.

ELEPHANT TRUMPETS

We're back at the water hole.

We're back at base camp
at the hottest time of year.

Yes, the big question is, what
effect will this raging temperature

have on the wildlife here

now that all of the other water
sources in the environment

have dried up and only our
water hole remains?

The water hole is now the main
source of fresh water

for 15,000 hectares of the reserve.

There's very little shade,

so getting here can be exhausting
for wildlife -

but, when water is
in such short supply,

it's worth it.

And on the first day of filming,

the water hole draws in
a thirsty animal

that we haven't seen before.

WHOOPING

Spotted hyena are one of the most
successful predators

on the African savanna...

..and an exciting
new addition to our species list.

I love hyenas. Look at that!
Oh, look at that!

Now, we didn't see them
at all last time.

It's just happily drinking,
it's on its own.

We're looking at the footage to try
and understand

what this typically nocturnal animal

is doing here during the day.

It's full, right?
Yeah. It's just eaten.

It's eaten.

Look, it's got a great big
tubby belly full of meat, there.

Hyenas often get thirsty
after feasting on a carcass...

..and it looks like this individual
may have made a kill nearby

in the past 24 hours.

It's pretty comfortable, isn't it?

Out in the open,
it's very confident.

I think this is probably an animal

that's getting to know
this water hole,

knows the lie of the land.

They live in clans

and, often, you know,
pretty numerous

in terms of, you know, the numbers
that you're going to get there -

groups of 20, 25 not uncommon.

Of course, they have this
reputation as scavengers,

but they are hunters as well,
they're really skilled hunters.

And, actually, it's more likely
that a lion will scavenge off them

than they will scavenge off a lion.

They have such a bad reputation

and yet they're actually kind
of gorgeous

and definitely really intelligent.

Yeah, smart, incredibly complex
social system,

governed by the females,
amazing behaviours,

and an essential part of the
ecosystem, of course.

It's such a privilege to see one out
during the day,

isn't it, though,
cos it's so unusual?

And I guess that's the advantage
of having all these cameras.

But, for other animals, however
thirsty they might be,

the presence of this predator
is likely to make them nervous

about coming to the water hole.

Only time will tell if this hyena
is here to stay.

20 cameras are positioned
around the water hole.

Calling up the footage offers
a unique insight

in how the heat
is affecting the habitat.

This is going back to the last
time that we were here.

And if we cast forward...
It's already quite dry.

Wow. OK, that got drier!

So there's lots of dry vegetation
there, but the vegetation is there.

If you cut to the next one.

Right. It's really barren.

It's so much drier. It's like
desertification, basically.

It is. The grass, the ground floor,
has dried out.

It's been eaten.

In terms of what's
available for herbivores to graze

around the water hole,

there's absolutely nothing.

All that is left to eat

are a few remaining leaves
too high to reach...

..and roots from dead grass.

Animals have to travel further
or dig deeper

to find anything nutritious.

The shape of the water hole's
changing a bit, as well,

whilst all the animals
have been coming.

A little bit on the top corner,
there, where it's shallower.

Presumably, they're just wallowing,
taking some of the material away.

At this time of year,

wallowing is one of the main ways

animals cool down.

They are hungry and tired,
desperately seeking shelter.

And it's this that allows
predators to thrive.

So, it's not surprising that,
on our first night,

we add new carnivores to our
species list,

including servals.

They are small savanna cats,

but are one of the most successful
hunters in the cat family.

They can leap up to three metres in
the air to catch birds mid-flight,

and they're known to hunt
up to 16 times a day.

The elusive African wildcat rarely
drinks water,

but uses its acute hearing
to precisely locate prey

around water points.

Spotted genets have retractable
claws to hunt in the trees

and down on the ground.

Now the water hole has become
a regular feature in the landscape,

smaller predators have plenty
of hunting opportunities

as small prey like rats
and hares come for a drink.

A few hours later, we get further
proof that the water hole

is a magnet for animals
from far and wide.

Look - hippo! Hippo are one of the
most powerful animals in Africa,

with canine teeth that can measure
up to half a metre in length.

This was something I really wanted
to see in our water hole,

and it was always on the cards.

You would think that,
in the foreground,

that's a source of
great temptation...

Oh, look at that!
..for a lonely wandering hippo.

They do move quite large distances
away from water,

looking for new water, of course.

But this hippo isn't searching
for water.

He's looking to graze.

Hippos walk almost 10km at night,

eating up to 40 kilos of grass.

Oh! To think that we could have made
a home for a hippo.

Now, come on! I'd put that on my CV.

With so much of the shrubbery
dried out, life is tough

for many of the animals here...

..but insects thrive

in this stifling heat, with the
humidity helping them breed.

This means lots of new insects
are spotted buzzing

around the water hole.

And insects aren't the only
new visitors. Migratory birds,

that have often travelled
great distances,

are also dropping in, including...

..the steppe eagle, which breeds
in Central Asia

before travelling
up to 10,000km to Africa.

HONKING

And Egyptian geese,
that pair up for life.

Once one dies, the other mourns
in seclusion

and often refuses
to mate ever again.

HONKING

A lot of the birds
flocking to the water hole now

are not coming to drink or bathe.

They're searching for food.

This is yellow-billed stork.
You can see how it got its name.

I've got a soft spot
for yellow-billed stork.

Now, when it comes to what they eat,
they are pretty much opportunists.

These animals will eat a frog
if they find it,

they'll eat a small snake
and a lizard

if they find it, they'll eat
fish if they can find them.

And that's what they're
looking for here.

What they're doing is they're
putting their beak into the water

and they're holding it slightly open
so that, if anything swims in,

they can snap it tightly closed
pretty quickly and capture the fish.

Super views! Look at that. Amazing.

I just feel a little bit sorry
for them,

because we've only just made
the water hole

and, at this point, there aren't
going to be any fish in it.

When the rainy season arrives
and the landscape floods,

new waterways will open up for fish
to find their way to our water hole.

But this won't happen for at least
another few weeks -

though no-one has told
the storks that.

It's sad, really, isn't it?

It is said that sometimes
the eggs of fish

are carried on the feet
of water birds -

ducks and things like storks.

You never know.

These animals may have brought
the very fish that they might eat

at some stage in the future
on those, their feet.

Birds are now the most frequent
water hole visitors during the day.

It's a far cry from the middle
of the dry season two months ago

when daytimes were busy
with many more species.

I have been studying the data to see
how much things have changed.

So this here is a plot of all
the animals' -

and not just some animals,
but all the animals' -

arrival times at the water hole.

Now, we're comparing our data
from the dry season

and now the hottest time of year.

So, when we were here last time,
you were looking at two peaks -

the animals were mostly
coming during the day

and then again at night.

But now you're seeing
a complete shift.

Buffalo that would arrive at dusk

are now waiting until darkness
at 8pm

before coming for a drink.

Elephants who regularly visited
during the heat of the afternoon

are now mostly arriving around 9pm.

Zebra, which used to come
around 11am every day,

are now turning up more frequently

between the hours of 2 and 4am.

What you're seeing is the animals
are preferring the night,

and, so, suddenly night has become
the new rush hour.

But night can be a dangerous
time to drink.

Mwiba is home to some of Africa's
top nocturnal hunters,

like leopard, lion,

hyena and wild dog.

On the fifth night, the highest
number of predators yet

comes to the water hole.

HYENAS CALL AND BARK

The spotted hyena returns,
and it's not alone.

OK, there's a clan moving in.
Look at that - seven.

Six. Now there's seven
at the moment.

There's eight there now.

I wonder if it's because
they've basically just built up

the confidence to come in here

or whether they have moved
into the area.

That's unlikely cos
they have quite stable ranges

and denning sites.

They do go wild sometimes. They do.

And they've got a remarkable
vocabulary - all sorts of whoops

and whistles and barks and howls.

Spotted hyenas are known
as laughing hyenas

because they have a distinctive call
that sounds like human laughter.

They can make more than ten vocal
sounds, but these can be modulated

to create even more meanings -

and they can hear each other's calls
from up to 5km away.

But, clearly, if they're moving
through the bush at night

and they're moving through
thick bush,

it doesn't matter
how good their nocturnal vision is.

They're relying on their sense
of smell

and, to communicate
with one another,

those calls that we hear
so frequently.

THEY CALL

They're not considered favourably,
are they, really? No, they're not.

They're looked down upon by many
African cultures and, certainly,

you know, Western cultures as well.

I think, because of their scavenging
nature, their nocturnal habits,

we're always fearful of things
that come out at night -

they're difficult
for us to see and understand.

Hyenas are highly territorial.

Now that they've discovered
the water hole,

their mere presence
is a threat to other animals

relying on this crucial resource.

THEY CALL

To help understand
the hyena's impact

on our emerging water hole
ecosystem,

I talk to Dr Meredith Palmer.

She's been studying Africa's
carnivores for more than a decade.

Meredith, we've got a number
of hyenas here.

The most we've seen at the water
hole is eight -

and, at the moment, it's dry.

Lots of herbivores are coming
to drink and then hanging around.

That must be ideal, therefore,
for the hyenas. Yeah.

So, having prey in high abundance
in a landscape

tends to favour hyenas.

Hyenas are apex predators
in this system,

exerting a lot of top down control
on what's going on.

Spotted hyena are the most abundant
large carnivore in Africa,

with an estimated population
of 47,000.

A lot of their success

comes from their complex
and highly adaptable social groups.

Clans consist of many non-related,
low-ranking individuals

led by an alpha female.

Working under her leadership,

they seek out areas
where prey congregate...

..like our water hole.

They know these animals
are going to be here.

The water hole is very good

because having a
high abundance of prey

allows their clans to grow
to very, very large sizes -

and if your clan is 40 or 50
individuals,

it's always going to win against
another species.

Dr Palmer's research suggests

that it's likely there could be even
more hyenas nearby

and, once hyenas are established,

the water hole becomes
a dangerous place to be.

Which could be why, following the
hyena clan visit,

days and nights are a lot quieter.

To find out where all these hyenas
are coming from,

cameraman Bob Poole's
been searching the area.

He spotted a hyena den
with three young cubs

just 2km from our water hole.

There, right there.

There they are.
There they are, look.

One, two, three.

And that's about the maximum
litter size

for one female, isn't it? Yeah.

25% don't get through
the first month,

and they're born with incisors
and really sharp teeth

and their eyes open -

and as soon as they're born,
they're fighting one another.

I guess that's one way to ensure
that the strongest survive.

But it's pretty brutal.

But by the time they get to
this stage, it's all sorted -

they already know who's top hyena.

Bob and I take a remote camera
to see if we can get a closer look

at these cubs without
disturbing them.

It's the same as those that we're
using at the water hole.

We can remote control it
from the vehicle here.

We can pan and tilt and focus
and expose,

and we'll get a view of it here.

Bob here is a bit underexposed
at the moment.

But the purpose of this, of course,

is to allow us to learn a little bit
more about these young hyenas

close to their den.

Yeah, the cubs are still there.

They haven't minded us...

..being this close.

You can see here how curious
these cubs are.

We're only about, I don't know,
six, seven metres away

from the entrance to the den.

It's in their nature -
they're opportunistic animals.

So they're always on the lookout
for new things.

ENGINE STARTS

We deploy our camera
and move back about 30 metres.

These are likely to be all of them.

I think the same litter.
They're mobile pretty quickly,

and then they need to get
on their feet and get moving.

So the female hyena
has the most fat in her milk

for any terrestrial mammal.

By eight months, they're showing
hunting behaviour,

and, within a year, they're out
hunting with the adults.

The arrival of an adult female
lets us spot something remarkable.

There it is - there, look.

A newborn hyena cub.

It's much smaller.

It's gone down. It's just gone down?
We'll see it again.

That was much blacker
and much smaller. It's tiny.

Yeah, yeah.

But when the female heads
underground, it doesn't take long

for the older hyena cubs to start
investigating our camera.

One of the cubs is now just walking
down the cable line,

having a good sniff.

Oh, hold on.

This is the cable being pulled
by the other one.

There it is - look, look.

It's got the cable.

BARKING

I knew that this would happen.

How long's that cable going to last?

They've all got the cable.
It's gone.

For some reason, it's stopped
recording and gone back to this.

There's just no input.

Oh, they've pulled the cable out.

I don't believe it!

They have. They're chewing it.

They've pulled it out of the back
of the camera.

That's not good at all!

That's a shame, because they'd just
plucked up the courage

to come right up to the camera,

so the camera did give us
the opportunity

to find out a bit more about them.

I think, from our point of view,
what's going to be interesting is,

you know, will these be the hyenas
of the future

that might visit our water hole?

After a few months, they will go out
with those adults,

and there's every chance that
they'll turn up down there.

Choosing a den so near
to our water hole

and therefore close to prey

is a key survival strategy

that will help this clan grow
strong in numbers...

..but the sight and the sound of
these powerful predators

will keep many other animals that
rely on this area for water away.

However, large animals
like this male elephant

are too big for a hyena
to take down.

And now that water is scarcer
than ever,

the water hole has become a lifeline
for one extraordinary individual.

We've seen him for over four
years now.

Mwiba guide Nuhu Mhapa
helps me to identify him.

It's amazing that he's still
surviving with such a trunk

that has been cut by a snare,
set by the poachers,

intending to catch some of the
wildebeest or zebras and so forth,

but, as the elephant moves
across the bushes,

grabbing these grasses,

then it just kept cutting the trunk,
so, it's painful,

but he has been with that kind
of wound for quite some time now.

Those trunks are so important.
They have multiple uses -

they are a hand when they eat,
they do help the elephants drink,

obviously, they suck it into
their trunks,

and then they
put that into their mouths.

But also they use it to signal
to other elephants.

Life is challenging for this
individual. Using their trunks,

elephants are capable of lifting
over 300kg,

something he will never
be able to do.

HE RUMBLES

Thankfully, he can drink.

But at this time of year, many
natural water sources have dried up

and are harder for him to reach.

Water deep enough to wade
into will help him to survive.

It must be also really sad
when you see this happen.

It is, it is.

And especially when you consider
that these animals,

they are long-living animals,

and you start to imagine
how hard it is for him,

just from this young age
all the way to 16 years old.

So it's tough.
It's very sad for us

because we humans have caused
these kind of problems.

So he's been affected very much.

So we've seen the effect
that the predators are having here

at the water hole,
but there is another species

that seems to be bullying just about
everything that comes for a drink.

It wants the resource
entirely to itself,

and our cameras can throw
some light on the matter.

QUACKING

Egyptian geese are aggressively
territorial at this time of year

as breeding begins,
and they've started fighting

over the water hole.

A mating pair
violently protect this patch

from other geese.

And it seems they're also
a surprisingly intimidating presence

to much bigger species.

THEY HONK

Not the quiet drink this giraffe
was hoping for.

Even predatory birds, like the
huge martial eagle,

are disturbed
by this boisterous couple.

THEY HONK

Whilst domineering geese are
unexpected,

it means our species list
has stopped growing at number 82,

as animals seem to be scared away
by hyena at night

or put off by geese during the day.

HYENAS CALL AND BARK

Over the next few nights,
hyena visits increase.

HYENA HOWLS

HYENA CALLS

And they're gaining confidence.

One night, a hyena appears
with evidence that it's been hunting

very close to the water hole.

It takes some scrutiny to determine
what this individual's doing.

It approaches the water hole, there,

carrying the limb of something that
it's either killed or scavenged.

Leg of wildebeest
it's got in its mouth there.

And rather than stop on the side,
put it down and have a sip,

it wades into the water
with that limb.

Now, some animals will wash
their food,

but it's not washing the food,
I don't think.

They will stash their food, hyenas.

They will cache their food.

You can see it's got a pretty much
full belly.

It's probably eaten as much
as it possibly can at this point.

It simply wades in
and then it comes back out.

Maybe it was thinking about caching
it in the water

and it had a change of heart
and went and hid it in the grass.

Sometimes, animals do
the strangest of things.

Now think about your own behaviour.

Sometimes, you do things
which are out of kilter

with not only human behaviour,
but your own.

Perhaps this hyena's
just got a leg quirk.

And that's the real joy
of having cameras set up like this -

we get to see things like this

that, in a lifetime of personal
observation,

you're highly
unlikely ever to get to watch.

HYENAS CALL AND BARK

With our camp only 800 metres
from the water hole,

we're having more encounters
with the hyenas

than we bargained for.

The crew even spot one looking
for food right in front of them.

And they're brave enough
to visit our tents,

howling through the night.

HYENAS CALL AND HOWL

One of the great joys of sleeping
in a tent

in sort of the African night

is not sleeping through
the African night

because there's such a cacophony of
noises out there -

and you're laying there, thinking,
"What's that? What's that?"

but you don't have to wonder
about the hyenas,

and there have been a
lot of hyenas in the camp.

In fact, when I got up yesterday,
there was a trail of footprints

right down to the opening
of my tent, and I love that.

I love the fact that you're sleeping
that far away from a large predator.

You never get that feeling
in the UK.

HYENA HOWLS

They are sticking to that whooping
sound that they make as opposed to,

well, more of the laughing sound,
but it is...

..it does sound like it's everywhere

and it's been going on
for a few hours

and we are really close
to the water hole.

They're even using the same trails
as us to get in and out of the camp.

But not all animals are threatened
by the hyenas

and, over the next few nights, we
add more new species to our list.

Bats dive-bombing the water hole

can eat up to 3,000 insects a night.

CROAKING

Toads absorb water directly
through their skin

so they don't need to drink.

CROAKING

This morning, a Mwiba guide

has told Bob a carcass
has been found close by.

There's been a kill right here
in camp. It's right down here,

just a few hundred metres,
and we need to go check it out

because apparently it's a
full grown adult waterbuck,

which is a sizable animal.

The carcass is just 600
metres from the water hole,

so, Bob is keen to find out

what might have been hunting
in the area.

It's gone - like, gone.

There's nothing here.

Can't wait to see the camera
trap footage.

It's remarkable, really.
This carcass is gone.

There's not even
any evidence it was ever here.

There's a tiny bit of a gut pile
contents, no stomach.

Just looking to see if there is
any lion prints.

So far, I only see hyena.

Hyenas will just rip this
carcass to pieces,

and when you look at their jaws,
they're extremely wide here,

and they have very strong muscles
on the top of their heads,

and they're able to crack
right through bones

and they actually eat them.

That's why, when you see their dung,
it's often just white

because they absorb so much calcium
from the bones that they eat,

but it just goes to show you that
nothing is wasted out here.

When the Mwiba guide found
the carcass last night,

he placed a camera trap on it.

Bob wants to confirm if this
is a hyena kill.

Guess what -
they came in the daylight.

OK, here we go, hyena coming on.

Oh, yeah. Beautiful shot.

Staring straight at the camera now.

Oh, wow. Here it goes.

Ah!

One hyena,
just struggling to drag that,

but doing it.

Oh, that's cool.

Flipped it over.

I was thinking it would
have been a whole, you know,

group of hyenas that came on first,

but it's just one individual.

But it shows you the
strength of this animal,

by dragging that huge carcass

and consuming
tremendous amounts of meat.

A hyena can eat 15kg of meat
in one go,

which is 25% of its body weight.

Phenomenal to think of.

Wow. This guy's really lucky.

He's not having to share it
at all at the moment.

Oh, hang on.

There's another hyena
in the background there.

Oh, here we go. Ha-ha!

He's been discovered,

and we've got one, two,
three, four hyenas.

They're really ripping into it.

All right. This now makes sense.

I didn't think one hyena
could eat that whole thing.

HYENAS CALL AND BARK

One has just taken off
with a hindquarter,

so that's how it goes.

Bit by bit, the thing is gone.

You know, they can devour
this carcass

in a very short amount of time.

With spotted hyena working together
to take down large prey,

it looks like they're now the
apex predator dominating the area.

Earlier in the dry season,

we discovered a local lioness

was also hunting near the water hole
to feed her cubs.

But we haven't seen her or the cubs
since we've been back.

Could the hyena have
driven them away?

To find out, Bob is going to
check the camera traps

we placed around the lion den,

3km away.

I'm anxious to see
what we've got here.

There's the mother, right there.

She came in looking quite defensive.

HYENAS CALL AND BARK

Wow.

Hyenas.

There they go, chasing upriver,

which is the direction
where the lion was.

HYENAS BARK

Hyenas will kill lion cubs,
any chance they get.

HYENAS CALL AND BARK

To discover if the lioness
and her cubs are still alive,

Bob has to extend his search.

He spots evidence of lions

over 16km from the water hole.

There's a carcass right there.

Maybe she's made a kill in here.

There she is.

I guess we just have to stay here
and see what happens.

Oh, oh, oh!

I just saw movement there.

Oh!

The cubs are right there.

Oh, my God!

They're right there.

I can barely see it.

Oh, my God.

Let's see how many...

One...

..two...

..three little cubs.

You know, you get so invested
in this stuff

and your mind plays tricks with you,
like, they're dead,

and it's like, wow, that's just...

It actually becomes quite emotional,
you know, to see them again.

The lioness has successfully moved
her cubs away from the hyenas.

Lion territories can range in size
from 20 to 600 square kilometres,

and cubs are often relocated several
times a month to keep them safe.

But other animals can't move out
of the area so easily...

..and have no choice but to
risk their lives

coming to the hyena-dominated
water hole.

This vervet monkey mother
needs to drink every day

in order to keep producing
nutrient-rich milk for her young.

The baby clings on tightly
whilst on the move,

something they're
able to do from birth.

The rest of her troop
are nearby to keep watch.

Vervet monkeys raise high pitched
alarm calls if they spot danger.

They use a different call
for each predator

to signal different
escape strategies.

With the coast clear,

she makes it to the water hole.

The baby gets all the fluids
it needs from its mother's milk,

so as long as she gets enough water,
the baby will survive the heat.

On day 12, it's 39 degrees,

our hottest day yet.

And a rather unexpected new species

turns up at the area
around the water hole.

COWS MOO

Ella, look at this.

Yeah, they're not supposed
to be here. Trespassers.

Right, so these cows are not
supposed to be in this area.

It's a protected area.

Around the outskirts of Mwiba,

there are many Maasai villages
that keep livestock.

Their cattle are banned
from entering the reserve

in order to stop overgrazing.

But there are no fences in Tanzania
between nature reserves

and human populations,

so enforcing this ban is difficult.

In this wild place where people
and animals live side by side,

there are no easy solutions,

and at the toughest times
of year, like now,

trespassing is likely to increase.

Where's the person that's looking
after these cows?

Or is there nobody
looking after them?

No, there should be someone
looking after them,

because, obviously,
they're potential prey

and they are currency, aren't they?

You know how valuable they are
to the local community,

so they don't let them ramble
and roam at will.

Look, there you are.
There's the human, there.

See, the thing is, he's going
to get fined. This is the thing.

He will get a heavy... A fine.

Yeah, he'll get a heavy fine
for being in this area,

and so he's taking a massive risk,
being here.

I guess I'm wondering why he's...

..why he's brought them in,
when there's such risk.

Perhaps this is his only choice.

It's either bring those animals
in here,

or they're going to die
of malnutrition... Yeah.

..and he's going to lose
his livelihood

and perhaps even the lives
of some of his family.

Presumably, he's taking
the risk of that fine

simply because there isn't
an alternative elsewhere.

Eventually, a Mwiba ranger escorts
this herd out of the reserve.

The presence of these cows

shows just how harsh the environment
can be at this time of year,

and why water is such an
important resource for all.

THUNDER RUMBLES

Finally,
after five months of drought,

three millimetres of unexpected
rain brings some relief.

THUNDER RUMBLES

It's not enough for grass to grow
or natural water holes to fill...

..but it does lead to a sudden
explosion of life - insect life.

Look at this beauty. Huge beetle.

I notice that the tent has
become a bit of an insect trap,

particularly at night,
with the lights on.

They're drawn to those lights,

and they're typically more active
at that time.

It's cooler, it's more humid,
best time to be flying around,

particularly if you're a large
insect like this.

We might call it a longhorn beetle.

It's got these characteristic
long antennae here,

typically extraordinarily sensitive,

for finding members
of the opposite sex.

And given its size,
I should imagine that this creature

has been living as a grub,
perhaps inside some rotting wood,

for a number of years.
And, having emerged as an adult,

their job is to mate and then
disperse, lay eggs and die,

get eaten by something bigger,
perhaps even more interesting,

something that might happen in the
space of just a couple of weeks.

And on that account,
I'm going to put it outside

so it can do its business.

ELEPHANT TRUMPETS

Our water hole has become
a lifeline for many species,

from the smallest to the largest...

..including the elephant
with half a trunk.

He has returned to our water hole,

and this time he's with a herd.

Elephants are highly social,

and other members of the group
are keen to interact with him.

They use their trunks
to communicate,

smelling and touching
each other's mouths.

It's essentially
an elephant handshake.

Half trunk does his best
to return the gesture...

..making a vital social bond...

..and confirming him as
one of the family.

Over the past two weeks,

we've seen hyena numbers increase,

and their visits intensify,
both day and night,

but we still don't know exactly
how many there are in this clan.

We're excited to have spotted
hyena around our water hole,

but it would be great
to know how many there are.

The trouble is, counting them
can be really tricky.

Firstly, they're nocturnal,
of course,

which makes them difficult to see,

and then they move around
in fluid social groups.

So, if you count six here,

two of them could be from the four
that you later count over here.

We clearly need a different method.

We need it to get dark and
we need to bring the hyenas to us.

Dr Meredith Palmer has
carried out similar experiments

all over the Serengeti...

..and can help us shed light

on how big our water hole
hyena clan might be.

So, Meredith, how are we going
to try and count these animals?

So, we're going to do
a call up tonight.

We're going to play some sounds
that might intrigue the hyenas

and bring them out of the bush

so that we can get a good
look at them and count them.

We're going to start by doing the
sounds of prey animal in distress,

playing the sounds of a warthog
that's having a very bad day.

If you're a hungry hyena,
this might be the kinds of noises

you would come and investigate to
see if you could get a meal.

We'll then play some hyena
social noises.

So we'll play the long
whooping calls of the hyenas,

and the calls I have are calls
of hyenas that don't live here.

They're strange hyenas.
They're foreign hyenas.

And if this was your territory,
if you were a resident hyena here,

you would definitely want to
come investigate

whatever strangers
might be coming through.

OK, so now we're playing a warthog
having a very bad day.

In terms of sort of disturbing their
behaviour, the ethics of this,

you know, we are playing
an artificial call,

we're moving them around
the environment,

but presumably only for a brief
period of time

over a short distance?

This is very noninvasive.

This is a very minimal
kind of experiment

to study their behaviour
and their population.

OK, shall we give a go, then?
Let's do it.

Let's wind them up
with a bit of wounded warthog.

WARTHOG SQUEALS IN PAIN

Hyenas come together en masse
for two key events,

either for a feast or when they're
trying to defend their territory.

Tonight, our two different calls

are attempting to lure them in
for both.

If we are able to
bring up any hyenas,

we can see the different spots,
we can see the different scars,

and we'll be able to identify the
different individuals that come up.

OK, what about range?

How far away...from how far away
can we bring them in?

So, we're playing these calls
quite loud.

The hyenas should be able to
hear calls played at this decibel

for about 3km.

If they're within that radius,
they might come investigate.

It's pitch black.

So we can see is the infrared
camera feed on the monitor.

And within just four minutes,

the first hyena turns up.

WHISPERS: Didn't take them long to
arrive, did it? Came very quickly.

Yeah, they must have been
in the immediate vicinity,

which points to the fact that
they're using this water hole.

So they'll be occupying this area.

Their quick arrival
suggests they live nearby,

quite likely at the den
I visited with Bob.

Oh, there's two of them.
Oh, there's two.

HYENA BARKS

That's them...
There's one over here.

Geese aren't moving, are they?

They're absolutely frozen solid.

They must know those hyenas
are there.

They're moving...

There's another...

Around the back...
Oh, there's another one here.

There's three.
Three, at least. Yeah.

Hyenas are highly social animals,

and their clans have very
complex hierarchies.

When two hyenas meet,

the subordinate animal lifts its leg
to the dominant hyena

so it can examine its genitalia.

There's one close here, though.

That one must be just out here.

The dominant female usually
has her tail upright

and the subordinates keep
their tails and heads down.

HYENAS CALL AND BARK

We're hoping to work out
which hyena is the leader.

There's another. There's another.

Four. Four, yeah.

Five, six!

HYENAS BARK

They must be just out here.

I mean, I can't see them,
it's completely black here.

We're using infrared light.

Those hyenas can't be
any further than...

..I don't know, six, seven,
eight metres away, just out here.

They sound so close. Yeah.

HYENA BARKS

And more keep coming.

You can see them now. Look,
cos they're here, aren't they?

The whole crew. Yeah.

They're surrounding this...

HYENAS CALL AND BARK

It's amazing to think that
these fantastic animals

are just a few metres away
out there.

How many are there at the moment,
Meredith?

11. 11?!
Wait, there's one more coming in.

11? Are you serious?

That's the most we've had here,
then.

Yeah.

With such a large group
gathered on camera,

we can work out that these
two smaller hyenas

are the most dominant,

by the way the others
are behaving around them.

God, I wish I had infrared eyes,
I really do.

Once the calls stop,

this clan soon moves on.

That's the last one, look,
dashing off into the darkness.

Yeah, what about that?

Top work, Meredith.
That was really good.

It's a brilliant sighting.

With 11 hyenas coming to the
water hole in just 19 minutes,

Meredith's previous research
suggests that it's likely

there are other hyenas in the clan

who are out of range
or at another kill.

She estimates there could be
as many as 25 in total.

I've got to say,
what an extraordinary experience.

It was so enigmatic, knowing that
these large, powerful predators

were just a few metres away
in the darkness.

We could hear them.

We couldn't see them.

Sadly, we couldn't smell them.

But they were just within reach.

Amazing. Amazing.

This hyena clan has
taken over our water hole,

and I've been compiling the data
to look at the impact

of their ever increasing presence.

We've been studying the number of
hyena visits at the water hole,

and what's interesting is that these
visits have continued to increase.

We spotted 73 visits.

Hyena now come nearly every day,

but with water running desperately
low across the reserve,

new animals still risk visiting
this crucial lifeline.

We've had an additional 17 species,

including the hippo and the serval.

That means our total count
of animals

that have turned up
to the water hole

since we opened it
just a few months ago is 88.

Over the past two weeks,

we've seen life at the water hole
completely transform.

But everything
is about to change once again.

The rains are already here,
a month earlier

and a lot heavier than usual.

In the coming months,
more rain will fall on Mwiba

than in London in a year.

A deluge that will have a
huge impact on the water hole.

We're back during the
height of the rainy season,

when there is an explosion of life.

One of nature's greatest spectacles,

the wildebeest migration, arrives,

bringing an influx of
new prey and predators.

It's just incredible to witness.

And our water hole ecosystem

enters an important new stage
of its evolution.

All of the animals that have been
coming here have been visitors,

but now we've got some residents.

In the baking heat
of the African savanna...

..as rivers dry up...

..animals flock to the water hole.

But we've never fully understood
how a single water source

can support so many
competing species.

So we're doing something
ground-breaking.

Welcome to Tanzania and to
the Mwiba Wildlife Reserve

and to this unique water hole
behind us.

We're working with the reserve
to create the world's first

water hole with a built-in
specialist camera system.

This war as a whole has a
half-submerged filming hide

right in the middle, and it's rigged
with remote cameras so we can see

every angle of animal behaviour
like never before.

When we were last here at
the hottest time of year...

..hyenas ran wild.

How many are there
at the moment, Meredith? 11.

11? Serious?

Now it's the rainy season
and the water hole ecosystem

is facing its biggest change yet.

Up until this point, all of the
animals that have been coming here

have been visitors, but now
we've got some residents.

An explosion of life brings
new species flooding in.

It's the most fascinating example
of swarm mentality in mammals.

And we reveal how our water hole
is set to be a lifeline

for generations to come.

From up here you get a great view
of the ecosystem.

This is the story of life...

..and death at the water hole.

We built our water hole in Tanzania,

500km from the east coast of Africa,

south of the Serengeti.

Mwiba Wildlife Reserve.

After five tough months of drought,
the rains are finally here.

More rain will fall over
the next three months

than in a year in London.

We're at the height
of the rainy season

and over the last two months,

the whole landscape
has completely transformed.

Yes, just look at this.

The dusty old dry river has gone.

Replaced with this fresh flush
of bright green grass.

And this has radically changed
life here at the water hole.

On average, it rains every
day for four hours.

These regular downpours
trigger over 200 species

of savanna grass to grow.

Mwiba's 53,000-hectare reserve

is now a lush, all-you-can eat
banquet for herbivores.

In this time of plenty, many
animals now have their young.

Over half a million mammal babies

and more insects
than it's possible to count

are born at this time
of year in the Serengeti ecosystem.

To see how this explosion of life
impacts the water hole,

we'll be recording 24/7
for the next ten days.

I'll be collating the data behind
every visitor...

..and adding to our species list
that's already at 88.

And I'll be replaying footage
to analyse the complex behaviour

behind every interaction.

But before we could start,
we had to do some repairs.

When we first came back,
the rains had been so heavy,

the edges of the water hole
were caved in.

We called in the Mwiba construction
team to help get

the water hole up and running again.

Our filming hide also suffered
in the deluge.

You see these lines?
Well, these are water marks.

Yes, the hide got flooded.

It got flooded up to about,
I guess, 1.6 metres.

It all poured into the hide,
filling the whole thing with mud.

Had to give it a good clean out.

Unlike a natural water hole,

ours is designed to keep
running all year round,

no matter what the environment
throws at it.

We can simply turn on the taps
to fill it up,

drawing water from a naturally
occurring sustainable source

47 metres underground.

This means Mwiba will be able
to keep this water hole going

long into the future.

The rainy season is already bringing
in an exciting array of new animals.

Look at this dragonfly here.

Look at that -
absolutely fantastic.

Hunting over the water hole.

There are over 3,000 species
of dragonfly.

This one, the wandering glider,

migrates a staggering 18,000km
from India to Africa...

..further than any other insect.

Bush crickets look similar
to grasshoppers,

but they have much longer antennae
that can be longer, in fact,

than their whole body.

This common diadem butterfly
male is black with white spots.

But the female is mainly orange,

mimicking the toxic monarch
butterfly to avoid being eaten.

The place is alive with insects now.

And you know, the water hole
has had its times -

it's had the time of elephant
and buffalo,

it's had the time of hyena.

Now is the time for insects.

And that's down to the fact
that it's rained.

All of the grass is growing.

All of the plants are growing
out here.

And that lush salad is a food
for herbivores,

not just the big guys, the mammals,
for all of the small invertebrates,

all of those caterpillars, grubs
and larvae which are out there.

We're only an hour into our first
day and this new burst of life

has added four species to our list.

But so far, no mammals
have shown up.

Last time we were here, hyenas
were taking over the water hole

at night, and we're curious to see

if they're still a dominant force.

But since the rains began,
our camp has been invaded

by a new nocturnal species.

I'm all of a flutter,
or rather I'm not,

but all of these termites are.
These are the alates.

These are the winged adults,
the males and the females,

the fertile males, fertile females
that have left the nest tonight.

And with the first flush
of rains, they will all emerge

from the termite mound
at exactly the same time.

And not just one mound - very often
all the mounds in that region.

So outside the tent - we're trying
to keep as many out as possible -

there could be probably hundreds
of thousands, potentially millions

of these insects flying
around at the moment.

Why have they done this?

Well, frankly, they've got to mate.

But also, this is a classic case
of predator swamping.

Imagine you're an animal here that
has a taste for termites.

Well, you could fill your belly,

but you wouldn't be able
to eat them all. Some would survive.

You swamp out with your sheer
abundance, the appetite

of all of those predators.

The larger females are very fatty.

They've got lots of fat reserves
because once they've mated,

they will shed their wings,
find a crevice in the ground,

crawl into it, and there

begin to form a new termite colony.

And until it gets going,

they need to live
on their fat resources.

They need those to lay the first
batch of eggs, of course.

And once they start their colony,
the females, the queens,

can be very long-lived.

Some of these ant and termite
species can live for up to 45,

maybe even 50 years,
but under the ground,

after just one night of flying
around in the free air.

What about that? What an existence!

Not for me.

Over the first 24 hours,
there's no sign of the hyenas

that were monopolising
the water hole last time.

In their absence, the water hole
community is reclaiming the site.

Vervet monkeys...

..giraffe.

Impala...

..elephant...

..and olive baboons.

It's great to see them again.

And it's a sign of the role
the water hole area

can play in the future...

..even when these animals
can find water everywhere.

This is our water hole troop.

Now we've seen these baboons
sleeping in the trees at the back.

We know that they're there.

We've caught them a few times
on the cameras.

But this is the first time we've
seen them in the rainy season.

The baboons have been coming
to the water hole

from the very beginning.

It was a vital water source
in the dry season...

..and now it provides a great
supply of food...

..all on their doorstep.

And to see them quite like this is
actually really, really spectacular.

They're just really owning
the water hole.

You can see a juvenile, there,
just hanging out on its mum's back.

Grass is around 80% water.

So at this time of year,
they're getting nutrition

and hydration with every mouthful.

They spend about 50% of their
day foraging for food.

If you see the way they're eating,
they're stripping the leaves off

and they're eating the shoots
and the roots.

By pulling up the grass,
eating it and passing it

through their digestive system,

olive baboons act
as seed dispersers...

..helping the water hole site
to stay green and lush

for the next generation.

Over the next few days, we watch
the same visitors that came

in the dry season to drink...

..now come to eat.

Despite there being food and water
across Mwiba,

these animals are still returning,
and for good reason.

We worked closely with the reserve
to create a water hole

that would support many
species for years to come.

Specifically choosing to build
it in one of the few patches

of open grassland amongst
all the acacia woodland.

The site's accessible
to lots of local wildlife

and, thanks to the new water hole,

is able to support them
all year round.

And now this emerging ecosystem
is showing signs

that it will also sustain
new life of its own.

It's exciting times down
at the water hole here,

because up until this point,
all of the animals that have been

coming here have been visitors,
but now we've got some residents.

And I'm feeling quite pleased
with myself

because I've scooped this out
of the water hole.

This is a large diving beetle.

They are ferocious predators.

This is the leopard of the water
hole beneath the surface,

in insect terms.

Diving beetles use the damp soil
by the edge of the water

to pupate in.

All the churned-up edges of the
water hole are a perfect

breeding ground for them.

So if you've got a large
predator like this,

you've got to have something
in the pool for it to eat.

We've got something. Look at this.

This mass of wriggling black
organisms down here

are tadpoles.

Yes, we've had amphibians
colonise the pool.

They've clearly come here, bred,
laid their eggs in the form

of spawn and they've hatched out
into these tadpoles and there

are plenty of them,
which is fantastic.

I'm really excited to say
that we've got our first

resident birds.

They're not actually at the water
side at the moment.

They're out doing what they
should be doing,

which is feeding.

This is a pair of Egyptian geese.

They started visiting the water
hole a few months ago.

But Egyptian geese
tend to stay put in an area

that has a good supply of water.

So with the water hole
being topped up regularly,

it looks like they're here to stay.

Their natural habitat
is along the Nile

and then south of the Sahara.

But I know what you're thinking,
you might have seen them in the UK

because they've naturalised there
and they're particularly common

in the east of England.

They're not technically
a goose, though.

They are, in fact, a large duck,
quite closely related

to our shelduck.

And they're a grazing animal.
That's what they're doing,

munching away on all
of this fresh grass.

Now, outside the breeding season,
they're quite gregarious.

You get them in flocks,
but when they come to breed,

you get them in pairs like this.

The male is the one on the left
there, with the pink, rosy bill.

And the female's on the right.

When this pair arrived last
season, they were quick

to make their presence known.

Since then, they've been
regular visitors,

and they've proved they're not
to be messed with.

When another goose came
to check out the new water hole,

our male made it clear
that it wasn't for sharing.

Even the arrival of a martial eagle,

a predator that can take prey
as large as an antelope or stork,

didn't put them off.

And neither did hyenas.

It seems this pair
want to have our water hole

all to themselves.

And should they breed,
they'll make a nest in one

of the thickets here,
and then they would hatch their eggs

and lead their ducklings across
the lawn and into the water hole,

the security of that water, to keep
them safe from ground predators.

And of course, with all of these
new species coming here,

that will supplement the diet
of those ducklings.

They're dependent on aquatic
invertebrates for the first few

weeks of their life.

But what about that?

Our water hole
really is becoming a home

for a great range of creatures.

It's from small beginnings,
like our water hole,

that aquatic ecosystems can build
to support a huge range of life.

20km south is Lake Eyasi.

A water source that's evolved
over 65 million years to be

a vital lifeline to one incredibly
beautiful species.

Looking down on this lake
is extraordinary.

It's like a bizarre
abstract painting.

Speckled with these rose
spots of...

..the greater and lesser flamingos.

These birds flock to Lake Eyasi
in their millions...

..using it as a stop-off point as
they migrate to breed further north.

The lake can sustain such
vast numbers of flamingos

because it's full of microscopic
algae called cyanobacteria -

plants that are poisonous
to most animals, but not to them.

And famously, they have that beak
which is upside down.

And using their tongue as a pump,
they filter vast quantities

of the water to remove
all of this food.

And there's another twist.

This is a soda lake.

The water is extremely caustic.

If they really need to, flamingos
are one of the only animals

that can drink here,
using glands in their head

to filter out the salt, draining
it from their nasal cavity.

It's still a difficult environment
for these birds.

The alkalinity of the water
means that if they get

just one little nick on their
leg, it becomes an open sore

and they soon perish.

For a harsh environment,

it's one which
is extraordinarily beautiful.

Lake Eyasi shows how much
freshwater sources

like our water hole are needed.

When we first designed it with
Mwiba, the idea was to make

a reliable water source for as many
species as possible.

But earlier in the year,
we were worried that it was only

going to be used by one animal...

..spotted hyena.

I've been looking back over the data
and it paints a stark picture.

Last time we were here, the hyena
dominated the water hole,

and in the end we managed to
identify 16 adult individuals.

Now, we've been logging
their movements.

They visited the water hole
73 times.

Now, compare that to our
situation right now...

..the heart of the rainy season.

We haven't seen a single
visit from a hyena.

You go from 73 visits to nothing.

To find out why they're no longer
coming to our water hole,

I return to their den site,
2km away.

Frankly, it looks to me as
if they've abandoned this den.

It's all overgrown here.

All of the vegetation
is standing up,

and if there were a boisterous
band of hyenas here,

then this would have all been
knocked down.

And look over here.

It's been raining, it's muddy,
there's not a single footprint.

And look, there are lots of plants
here, grass growing through.

These would have all been knocked
down if this was still occupied.

I'm hoping our camera traps

might give me some clues
as to why they've left.

A giraffe.

There's a couple of hyenas -
there's an adult in the foreground.

There's a cub,
another cub behind it.

Oh, look at that, two of my
favourite African mammals

in the frame at once -
the fantastic crested porcupine

and a young hyena.

And guess who comes off the winner.

Porcupine, of course. Look at that!

A bit more porcupine action here.

You see those quills erected?

The porcupine is clearly agitated.

Now, you might be wondering, why
has a porcupine come to a hyena den?

Well, hyenas bring lots of parts
of the things that they've been

scavenging back to the den,
including plenty of bones,

and porcupines love gnawing bones

because they need all that calcium
to produce their spines.

But it's unlikely that a few small
porcupines would scare them away.

Oh, my goodness,
look at that. Buffalo.

There were a whole herd of buffalo
clearly moving through,

trampling over this site.

Maybe this was what put them off.

Maybe it was just the abundance of
other animals that drove them away,

and certainly at night,
with all of those buffalo,

they wouldn't want their
cubs emerging

and the risk of them getting
trampled.

I think I know WHY the hyenas
have moved dens,

but the question is -
where are they now?

We send out several film
crews to find them...

..and one of our cameramen
spots their new den,

2km from the previous one.

They appear safe and well.

Spotted hyena can have many old den
sites spread across the savanna.

It looks like this clan
moved their pups to an area

with fewer animals.

In a year, these pups won't be
so dependent upon the den.

And they may return to the
water hole with their clan.

With no hyena in the vicinity,

the water hole is a safer
place for prey once again.

There are over two million
impala across Africa.

They time their breeding season
with the rains, and their population

spikes by hundreds of thousands.

It's exciting to see this new
generation come to the water hole.

Ooh! There we are.
The impala have turned up.

And they've brought their young.

Look at that.

It is undeniably cute.

Big ears, big eyes.

Groups of young impala are
called creches.

This is the first time we've seen
them at the water hole.

So these have been born a few weeks
ago. And initially, of course,

they'll be dependent
on their mother's milk.

But then when it comes to them
moving onto solid food,

they need to time that so that
they've got this crop of ripe,

green, highly nutritious,
fresh grass.

Looks to me as if this group of
impala timed that birth perfectly.

These young impala are likely
to be regulars at the water hole.

Patterns of behaviour set now

should mean they'll remember this
oasis in the future.

The rains don't trigger
the birthing season

for all of our water hole
community.

5km away, wildlife cameraman
Bob Poole is discovering

this is actually a peak time
for mating

amongst many of Mwiba's herbivores.

OK, now watch this female.

It's incredible.

She comes up to the male,

then she rubs her neck
against his like that.

It's definitely a sign
of affection or interest.

At this time of year, amorous
giraffes use their sense of smell

to help identify if a female
is ready to mate.

So the male giraffe right now
is trying to determine

whether the female in front of him
is in the peak of oestrous.

Oestrous cycles in giraffes,
like human menstrual periods,

help identify when a female
is ready to mate.

They occur every two weeks,

but a female giraffe is only
fertile for four days or less

during this time.

She gives off pheromones
which he senses through sensors

that are in the top
of his lip, there.

Giraffes mate all year round.

But there is research
that indicates breeding increases

with periods of
high food availability.

All the leaves are so plump
right now.

I can see the way that they use
the tongue

to strip the leaves off the twig,
which is, of course,

loaded with these big thorns.

And everything around here
has a thorn on it.

In fact, this place is
called Mwiba,

which literally means "thorn"
in Swahili.

All of this food means
other herbivores like zebra

are also getting ready to mate,

and sometimes competition
between stallions can get physical.

Look at this!

There's so much action going on
right now. The... the stallion here

is racing around trying
to round up the zebra females,

and you can see him racing
across in front of us right now.

And now he's coming back to
probably his harem right there.

The young males have to
struggle for dominance.

He could get kicked out
by another stallion.

These are very social animals.

They live in family groups
and they have an order,

a pecking order, essentially,
just like horses do.

They're constantly having to put
each other in their place

so there's a lot of fighting
and testing, and all kinds of action

going on all the time,
to sort of really work on who's who

in the family and where they sit
in terms of the pecking order.

And some have already
had their young.

This foal is just four weeks old.

The little foal, to the right,

would be his first foal
of this rainy season.

During this time of plenty,
the savanna is overflowing

with calories for new mums
to produce milk.

And when babies are ready,

there are swathes of grass
waiting to be grazed.

The water hole is getting busier
each day with insects...

..and we spot two interesting
new species for our list.

Hoverflies are harmless,
but they mimic stinging bees

and wasps to put off predators.

Leaf roller moths pupate
from inside a rolled-up leaf,

sealed shut with the
caterpillar's silk.

All the insects are attracting

more new bird species,

including...

a red-necked Francolin,

a relative of the pheasant.

It's a wary bird,

often staying hidden from predators
in deep cover

and only coming out
in the open to feed.

A three-banded plover, named
after the black and white bands

on its chest.

They hunt by sight
for insects, worms

and other invertebrates.

And we have another new
resident bird,

taking our species list
to nearly 100.

This has made my day. When we were
here last time, there were a pair

of lesser striped swallows

prospecting to make a nest
inside our hide.

Earlier in the dry season,

our cameras captured the moment when
these swallows were first choosing

where to build their nest.

These swallows typically nest
under bridges for protection

and the roof of our hide
offers a great alternative.

The water hole has also provided
perfect nest-building materials.

Both birds use mud for construction,
and you can see this one's beak full

of mud, deciding where
to start plastering.

I really hoped they would
move in here.

And look, they have. And it's a
beautiful structure, as well.

Now, it's slightly different
than a typical barn swallow's nest

that we see, which is an
open cup.

Here, they close the cup and then
make that neat little tunnel there -

I suppose to try and keep predators
out, maybe things like snakes.

It's a fantastic construction,

welded into the corner of the
building there.

A little work of art.

So I'm really pleased
that they've used our hide

to make their home.

I'm pretty certain that we've
got young in here.

I've been watching the two adults
hunting outside together,

and then going in one at a time,
delivering food.

Feeding chicks is a full-time
job for both parents.

We're seeing them bring
back food every 20 minutes.

If they were still incubating
or brooding, typically

one's off the nest whilst
the other one's sat on it.

But because they're both active
away from the nest,

I reckon there's young up there.

So we've done a great job
for these swallows here.

We provided the water and in turn
the food, and then we provided

the structure for them
to place their nest.

It's good. I like that.

And, even better -

because swallows return to the same
nest site year after year,

our hide could well be their
home long into the future.

And the water hole is going
to provide the swallow chicks

with all the food they need

because both pools
are teeming with mosquitoes.

Mosquitoes lay their eggs on water.

Each female can produce up to 500

in her one-month lifespan.

Many mosquito species stay
within a few hundred metres

of where they're hatched,
so it's likely they'll be

a regular feature at the water hole
every rainy season...

..providing a reliable food source
to birds like these swallows.

Insects and birds are important
foundations for a healthy ecosystem,

but we're working closely
with the Mwiba guides to make sure

the water hole can also attract
and sustain Africa's megafauna...

..the most important
of these being elephant.

ELEPHANTS MAKE RUMBLING SOUND

Elephants are keystone species.

They help disperse seeds, and also
create pathways to water holes

as they walk to them.

We've had over 100 individuals,

and one extraordinary half-trunked

elephant used this lifeline
over the past six months.

Mwiba guide Eugene Raymond
is confident that these elephant

populations are likely to keep
coming back to the water hole.

It's unbelievable
that they have this ability

to remember places, areas,

and with experience,
they're able to find.

An incredible
ability also to find water.

Now, we've seen this animal
at the water hole here, and we know

they've got phenomenal memories,

it's going to be interesting to see
whether it remembers the water hole

come the dry season -
when it really needs that water.

Research shows that elephants
can remember the locations of food

and water for up to a decade,

even when seasonal and environmental
changes alter the landscape.

A permanent, refillable
water hole like ours

should be an elephant
oasis for many years to come.

And Eugene has been pleased
to see so many herds coming

to the water hole,
because it's the matriarchs

that lead their families
and remember where to go.

This mama elephant,
or Tambo we call her,

who will be able to remember these
places and come back into the same.

And that's why the herd
put trust in them.

And they would normally try pass
this on into the next generation

by just, you know, testing as
individuals the ability to navigate

the rest of the group members
and remember these places.

This comes with experience. Age.

It's a bit like you going shopping
with your grandmother, isn't it?

It's true, yeah. She knows
where the best shops are. Exactly!

Where to get the best deals
at the right time of year.

Absolutely true. Yeah.

Elephants can eat up to 250kg
of foliage,

and drink up to 200 litres
of water every day.

They're one of the heaviest users
of the water hole...

..which is why it's so exciting
that Eugene and the Mwiba team

will keep refilling it
in the future.

We've had word of a new species
in the area that could drink

more than all our Mwiba
elephants combined.

The world-famous wildebeest
migration has been making its

epic journey 400km south from Kenya,

and it's now 10km away
from our water hole.

Together, these animals can drink

up to 13.5 million litres of water

and eat up to four million kilograms
of grass in a single day.

So that's where we are
right now, that blue dot.

And you can see they're
heading right towards us.

To get an idea of the impact
they'll have on the area,

and our water hole community,
I'm taking to the air.

This is one of the most astonishing
sights that I've ever seen.

We're looking down on the world's
largest mammal migration.

Just sensational.

There are thousands of wildebeest
beneath me in a long line

stretching across the savanna.
A group of perhaps 1.5 million

of these animals that are
constantly on the move

in this Serengeti ecosystem.

They make the journey, which lasts
a full year and covers 1,000 miles,

clockwise from here, all the
way up through the Serengeti

to the Maasai Mara
and then back down again.

Right now, they're at the
southernmost part of that cycle,

on the edge of Mwiba reserve.

While I track the migration
from above...

..Ella is getting a closer view
on the ground.

They're now 8km
north of the water hole.

They undertake this crazy journey
because of this,

because they're after these
really nutritious grasses.

Essentially, they're storm chasers.

They're chasing the rains
which feed these grasses.

If you look at their bodies,
they have these really significant

incisor rows and loose lips,

and that's to help them rapidly
eat that grass.

They consume up to 16kg a day.

Look at how much they're
moving in unison.

They're moving in formation, and
yet there's no clear leaders.

It's the most fascinating example
of swarm mentality in mammals.

Because wildebeest have no leader,

the migrating herd often splits
into smaller groups

that circle the main mega-herd.

Joining them are thousands of zebra.

They graze in harmony with
the wildebeest because they

eat different parts
of the same type of grass.

From above, I can clearly see
how this huge number of animals

might affect life
at our water hole.

Their movement has an extraordinary
impact on this ecosystem.

Firstly, directly - that grazing
pressure is preventing

the regeneration of trees.
It's keeping this as open savanna.

Also, the impact that they have
on the predators.

This is, of course, an enormous
amount of meat on the move.

Many animals will take
advantage of that.

Lions will simply stay
in their territories

and eagerly await the arrival
of the wildebeest.

Ditto the crocodiles that are
stopped in those rivers

which they have to cross en route.

Then lastly, there are predators
that will go out for the day,

follow the wildebeest,

but then go back to their dens
in the evening, or in the morning -

depending whether they're diurnal
or nocturnal.

Things like wild dogs
and those spotted hyenas.

On average, the migration travels
up to 5km a day.

It looks like this year,

they're going to skirt around
the water hole site,

so the natural order of our
ecosystem remains unchanged for now.

But next time, it could be
a different story.

The water hole will always
attract new seasonal visitors.

But in the six months since
being built, it's becoming

a permanent home for some.

And it's our filming hide,
perched in the middle of the water,

that seems to be the
location of choice.

You may not be, but I'm
very pleased to see

that these animals have taken up
residence in our hide.

This is a paper wasp.

It's one of a number of species

known as Belonogaster.

And they're very similar
to the social wasp

that we have in the UK -
in terms of their behaviour,

not their physical appearance.

You can see it's got a much
narrower, longer waist there

towards the end of the abdomen,

and those beautiful red wings.

This is a queen and that nest
has just about got started.

So she's arrived, chewed up some
paper on a tree out here,

and she's made that tiny
little petiole - that strong piece

of fabric here, which is going
to support the whole nest

and it's going to grow considerably
larger than this.

Then she's made a couple
of cells,

and into those she's laid some eggs.

And at the moment,
she's having to fly out and hunt

to feed those grubs, which are just
nestling in there.

Probably caterpillars is going to be
the main source of food

that she's looking for.
Something soft and easy to chew.

And she'll come back, and then
she'll scrape the edge of the comb,

and the larvae will come up
and she'll delicately feed them.

She's a bit mobile at the moment.

You can see her moving
around there.

And you can see one of
the grubs there

with its head capsule just
coming out of the cell.

Maybe it's a little bit hungry.

when they emerge, those workers
divide themselves into castes.

They do different jobs.

So, some will be guards.

Others are foragers, and they
will go out hunting

for those caterpillars
to bring back.

Meaning that the fertile queen,
the most valuable

part of this colony, will be able to
remain in the safety and security

of our hide on the nest.

People sometimes say,
"What are wasps for?"

My reply is always simple,
"What are you for?"

You shouldn't misjudge wasps
just because they sting.

They're fascinating insects and an
integral part of the ecology here.

Now, down by the water hole
at the moment, we've got this lush,

green carpet of grass being munched
by loads of herbivores,

and they're not all big
animals like impala.

A lot of them are small things,
like the caterpillars.

And if these guys weren't
controlling those caterpillar

populations, then the whole
place would be defoliated.

The ecology would collapse.

You need everything in place to
maintain that balance of nature,

to keep that beautiful, dynamic
harmony working.

And that's why you need wasps.

Wasps are cool.

The paper wasp brings our list
up to 101.

The number and variety of species
is impressive,

considering the water hole is only
six months old.

But how does it compare to
a long-established,

naturally occurring
freshwater source?

Mwiba is part of one of the oldest
ecosystems on Earth...

..the Serengeti.

And 7km from our
water hole is Sele Springs.

It's hundreds of years old,
but almost disappeared

in the dry season.

Thanks to the recent rains,
it's full again.

To find out how this ancient spring

contrasts to our fledgling
water hole,

we've brought
in Dr Meredith Palmer.

She's been studying the Serengeti
ecosystem for over a decade

and has been using camera
traps at Sele to gather data

over the past six months.

So here, if we're focusing
on the mammal species,

we can see that Sele Springs
would be a very similar number

of animals showing up.

Incredibly, our new water hole
is sustaining as many

species as Sele.

And there are some animals
that are only coming

to our water hole.

We're getting more mongoose...

..porcupine, rabbits, spring hares,

a lot more monkeys here.

At our water hole, on the other
hand, we're getting servals.

We have things like waterbuck...

..kudu.

Dr Palmer's research shows that
wildlife is also behaving

differently at each site.

Despite it being new in
the landscape, many animals

are more comfortable drinking
at our water hole than at Sele.

So, impalas are spending far more
time there than they are at Sele.

We can see the same
with the giraffe.

At our water hole, impala stay for
around half an hour each visit.

That's twice the length of time
that they spend at Sele Springs.

And that's also the case
for zebra and giraffe.

Any theories on why that might be?

It could be a safety issue.

Our water hole
is a little bit more open,

you can see the predators coming.

They might feel safer
to stay longer.

By working with Mwiba to build
our water hole in an open area,

we've made a safer place
for many herbivores.

Predators have fewer chances
to hide,

and as a result, a lot of species
seem to take their time

at this brand-new water source.

And the more wildlife feel secure,

the more likely it will return
in the future.

Our water hole's the new kid
on the block

and it's still done pretty well.

I mean, comparatively, we're looking
at similar numbers

of mammal species, that's...
That's really impressive.

Yeah, I think it's amazing how
quickly the community assemble

at our water hole, how many
animals we got

and how soon they showed up.

We're seeing the same forces shape
animal behaviour

at our water hole and other
water holes like this.

And even though it's still
an experiment in progress,

the community is still jostling
and assembling

and becoming a water hole.

Having the opportunity to look
through all this data,

and it's such a fine scale,
has just been really fascinating.

Mwiba are planning to keep studying
the water hole in the future

to reveal the long-term impacts
of water availability

on African wildlife.

And their ecosystem manager,
Mark Ghaui, is excited

by the potential of having
this constant water source

in the reserve.

This started off as a little
experiment, but it's been

a remarkable success, hasn't it?

Yes, six months has gone really
quickly and it's amazing

to see and feel how much part
of the landscape it is.

I think to be able to guarantee
water will just be, without a doubt,

beneficial for these populations.

Water has been in such
short supply in Mwiba

that conflict has been increasing

between wildlife and human
populations...

..who often use the same natural
water sources.

Mark hopes that the new water hole
might be a possible solution

and has been keeping an eye
on incidents in the area

over the past six months.

In terms of human-wildlife
conflict,

do you think that this has played
any small role in reducing

that in this local area?

We are close to the boundary
and also close to watering points

that communities use and I think
to have a water source here

that they can access without
leaving the reserve

and troubling those communities
will definitely...

I think we'll definitely
see a reduction

in human-wildlife conflict
as a result.

Conflict is a growing problem across
Tanzania, where there are no fences

between wildlife reserves
and villages.

Many tribes are herders, keeping
thirsty animals like cows

that need to drink up to 100
litres of water a day.

There's been an explosion in cattle
over the past three decades.

Now, there were approximately
30 million cows

across the country.

It's putting a huge strain
on supplies.

And when water runs low,
people have little choice

but to violently protect that water.

Last year on the outskirts of Mwiba,
there was one human fatality

and countless altercations
as humans and wildlife

fought over food and water.

But in the past six months, there
have been no reported incidents

near Mwiba's park boundary...

..thanks, in part,
to our water hole.

What about the long term
legacy, then?

I think it's going to be a big part
of our landscape going forward.

I think, yeah, from our perspective,
it's just getting started.

And, yeah, it's been wonderful
to see how animals have fixed

their lives and their routines
around it, how they've engaged

with it and I think we'll be
seeing that

for many, many years to come here.

to our species list.

The hoopoe is named
after its distinctive call.

ECHOING WHOOP

The woodland kingfisher
is one of the many kingfishers

that don't just eat fish,

but also hunt insects,
frogs and snakes.

The rufous-tailed weaver is
a monogamous bird that's only

found here in East Africa
and nowhere else in the world.

We've been recording a vast array
of animals over the last six months.

And I'm digging into the data
to find out what this unique

experiment has revealed
about how wildlife interacts

at a water hole.

We've had our cameras
on for over 1,400 hours

during the six-month period.

We've got data coming out of our
ears and we can see our

final figures now.

We've recorded 105 species
visiting our water hole...

..including 26 different mammals.

GRUNTING, SQUAWKING AND ROARING

If we look at them according to
size, it's the mega-herbivores,

elephant, buffalo and giraffe,
that came in the biggest numbers.

But they didn't spend the most
time here.

Clocking up an impressive
19 hours...

..the impala stayed longer
than anyone else...

..enjoying the safety provided
by the open landscape

around our water hole.

Surprisingly, though, they weren't
the most frequent visitor.

It was the hyenas that came
to the water hole

more than any other species...

..making a total
of 121 separate visits.

Now, this personally is actually
really surprising to me.

I wouldn't have expected
that a carnivore

would have been the most frequent
mammal to the water hole...

..but they were.

We always assumed water-dependent
herbivores would visit

the water hole the most.

But it's actually good news
that hyenas came so frequently.

They're known as the health
police by scientists,

because they can eat animals that
have died from diseases

that are deadly to other species.

Their stomach acid and immune
system is so strong,

they're one of the few animals that
can digest anthrax and survive.

If they return, they'll help keep
this new ecosystem in balance.

This has been
an extraordinary venture.

We've had a rare chance to see
a whole community of wildlife

taking shape around a water hole
that six months ago

just didn't exist.

And the great thing is...

..it's here to stay.

Our water hole will benefit
future generations of wildlife

and also the people it shares
the landscape with.

When we arrived here,
this little corner of Africa

was just a dusty piece of savanna.

But over the last six months,
we've seen

a remarkable transformation.

It's undeniable - this experiment
has become a huge success.

We did wonder if the animals
would come, and they did.

And they are still coming.

You know the best thing?

We've made something
that a whole bunch

of animals now call home, and that
puts a smile on my face

and makes me feel pretty good.