All language subtitles for Boteti The Returning River

20 years of drought have
turned the Boteti River

in Botswana to dust.

The animals that live here have
to endure season after season

of excruciating hardship
just to keep alive.

To survive in this harsh
desert they've had to

adapt their behaviour.

But now, the long and dry
era is about to change.

Water floods the dusty river bed.

Desperation gives way to hope
as the Boteti flows once more.

The Boteti River is a jagged
lifeline that runs into

a harsh desert.

It connects the lush water
wilderness of the Okavango

with the fickle wastelands of the
Makgadigadi pans.

For centuries the floods
of the Okavango have spilled

into the Boteti and brought
the desert to life.

But over the past few years,
this supply has gradually dried up,

and what was once a former paradise
has become a killing field.

Herds of zebra fight over
what little water is left.

These last pools are their
dry season lifeline.

But they're not the only
creatures struggling

in this harsh environment.

Surprisingly, some crocodiles
still survive here.

They were stranded in this area
when the river stopped flowing.

Crocodiles need warm sun
and cool water to regulate

their body temperature.

But these shallow pools
are lukewarm, so the crocodiles have

devised an ingenious way
to lower their temperature -

they have dug caves
in the dry river bank

where it is 10 degrees Celsius
cooler than the outside.

Crocodiles can walk over land
but they can't cover distance.

The next closest water
is the Okavango delta,

80 miles to the north, too far
for these short legged reptiles.

Making them long-term
prisoners of the Boteti.

But over the years of drought,
these crocodiles have not only

learned how to keep cool,
they have completely

changed their hunting behaviour.

They now focus on an
unlikely food source.

Huge flocks of queleas
converge on the Boteti pools.

Strength in numbers is a popular
strategy, but sometimes

flocking is deadly.

The birds are also thirsty,
and they descend on the water's

edge in force.

The collective weight of the tiny
bodies bend the reeds,

pushing some of the
queleas into the water.

The crocodiles persist
and eventually make a full meal

of the tiny birds.

Waterlogged survivors
paddle for the shore.

But a lurking marabou
is waiting to pick them off.

Evaporation is at its
highest now and the pools

are becoming muddy shallows.

For one female zebra, the situation
is becoming increasingly desperate.

She's early in her pregnancy,
and she'll eventually need fresh,

green grass to supply her unborn
calf with milk when it arrives.

Water along the Boteti
is so scarce that every pool

is a sought after commodity.

Elephants are clever in their use
of the precious water.

When they drink they don't waste.

They step carefully into the pool
to avoid lifting the mud

from the shallows.

They need 250 litres a day,
so they need to think ahead.

They move further down
the dry river bed.

The elephants create mud by stirring
up the water with their feet.

The mud cools them,
and gets rid of parasites.

But it's sometimes difficult
for them to haul themselves out.

The last part of their daily
routine is a sand bath.

A sprinkle of fine sand cements
the mud and provides protection

from the sun.

Unlike most of the other animals,
these elephants can range

into the adjacent desert
to find nutritious food.

They hunt down certain
twigs and barks that

nourish their huge frames.

But their favourite
parts are the leaves.

At first glance

the foliage of this winter
wilderness seems barren.

But acacias have a way of drawing
every drop of moisture from the soil

to keep their tiny leaves alive.

Sooner or later, though,
the herd will have to return

to the river, and sometimes they
roam further than they intended.

They get thirsty
and have to run back.

But the waterhole is overcrowded.

Every animal needs to drink.

The pregnant mare is in the queue,

patiently waiting for access.

The front ranks become agitated
and churn the water into mud.

This sounds the alarm
for the elephants.

They know that this water needs
to be saved, and churning it to mud

will mean far less to drink.

Eventually they take charge,
they cannot let the unruly zebras

destroy this precious waterhole.

More and more zebra come
to drink at the river.

But the stagnant pools
have a welcoming committee.

The vultures have worked out that
every animal in need of water has

to come to the Boteti -
right to them.

They know many are already
on the verge of death.

All they have to do is wait.

Jackals are clever, they follow
the throng of scavengers,

there may be something
in it for them.

Eventually their patience
is rewarded as a zebra collapses.

Like the stranded crocodiles,

hippos are also heavily
reliant on water.

And this, their last
polluted pool is drying.

And hardening.

In the cool of night they're free
to feed in the surrounding scrub.

But when morning comes,
they have to return to the cool

of their last wallow.

Hoping that there's enough mud
to coat their sensitive skins.

This remaining pod hasn't
raised young for years,

all calves are killed immediately
at birth by the pod male.

There just isn't room for one more.

The hippos are also
long-term Boteti inmates.

Another season like this
and they will be cemented

in their muddy tomb forever.

By mid-morning the scavengers have
reduced the fallen zebra to a pile

of skin and bones.

One creature's famine is another's
feast, and the jackals join in.

They've left their territories
out in the desert.

But like a Cold War meeting
in no-man's land, this encounter

is not friendly.

They compete with each
other for every bite.

While some jackals work the Boteti
pools, 50 miles into the desert,

others have a different
survival plan.

Without the summer rain,
these plains are dry and dusty,

but this hardy individual can spend
the entire year out here.

It knows that where
there's old elephant dung,

there are insects.

To find them, it has to listen.

It focusses on sound,
pinpointing the location.

It gets all the nourishment
and moisture that it needs

from this food.

But even out here,
it has competition.

The meerkat family comes out
of their den in the morning

to forage for insects which they dig
out with long, strong nails.

They hunt for food together,
alternating sentry duty.

They don't share their catch
but quickly eat it there and then.

The saviours of this desert
environment are termites.

They are the favoured food
of many insect eaters.

These primitive animals form huge,
well organised colonies that

go deep underground.

Harvester termites feed
on any vegetable matter.

And when the grasses dry out
it's time to harvest.

The blind workers spread
out over the plains,

and efficiently clip the grass
blades which are taken

underground to store.

A wolf spider has strategically set
up home near the termite's nest.

Because they cannot see,
the termites don't even know she's

on the prowl.

She hunts during the day and has a
well developed set of eight eyes,

which she relies
on to track her fast moving food.

She collects as many
termites as she can,

greedily stashing them
away to feed on later,

in the coolness of her burrow.

But the entrance is a tight fit and
this time,

a clump of grass forms a wedge.

With her head stuck below ground,
she's exposed and vulnerable

to attack from the meerkat clan.

With difficulty she squeezes in.

Eventually, she makes it.

But the termites are not
out of danger yet.

The most vicious of termite killers
has found the entrance

to their nest.

The giant matabele ants attack.

They bite the termites
and the sting paralyses them.

Systematically the ants enter
the termite hole and pull out

body after body.

The dead and paralysed termites
are taken to the ants' nest to be

eaten by the colony.

As the execution of thousands
of termites continues,

slow moving bull elephants
follow invisible roads

towards a mystery source.

They have struck out from the Boteti
and are heading east,

into the dry Makgadigadi.

No one knows how they navigate,
but they head for far off water

points in an ancient map network
etched in their heritage.

When the bulls find a baobab
they take advantage of the shade

provided by the huge trunks.

These trees are like beacons
in the desert, and the elephants

gravitate to them.

The elephants stay here
through the hottest hours

of the day, when temperatures can
easily reach 45 degrees Celsius.

These large, dark animals
have no sweat glands

and they overheat very quickly.

Flapping their ears is the most
efficient way of lowering body heat.

The breeze that is generated cools
the blood flowing in thousands

of capillaries near
the surface of the skin.

They will mobilise when
the temperature drops.

But ahead of them, lie miles
of endless, dry scrub land.

Some don't make it.

Heat exhaustion affects
an elephant radically,

these bulls need to time
their journey just right.

Out on the distant plains, the summer
rains have finally arrived.

But 100 miles away at the Boteti,
the skies are still clear.

Yet the smell of rain is in the air.

An escape route from the Boteti
hell has been opened,

and the zebra jump
on it immediately.

For the pregnant mare,
this is one last gauntlet to run

before a little nourishment
becomes available.

She'll eventually have
to return to the Boteti,

but for now, its not
worth thinking about.

During this trek the animals hardly
drink, rest or feed.

But at least there's
hope at the other end.

25000 animals make the journey

in the second largest zebra
migration in the world.

Exhausted, they arrive
at their summer pastures in a spray

of welcome rain.

For the next few months
they will have an unlimited supply

of food and water.

The bull elephants that struck out
earlier are ahead of the zebra,

and they have found one of the pools
en-route to the plains.

Their large shapes are a beacon
to the thirsty herds.

But the elephants are possessive.

Perhaps they remember
the previous confrontations over

the Boteti water.

The zebra have no
choice but to give way.

On the plains of the Makgadikgadi
there are no running streams

or natural springs of underground
water, when the rains stop

at the end of summer,
the pools will dry up.

The bulls take their time,
but before they finish,

more travellers arrive.

The zebras have to
wait a little longer.

Once again, the smell of water
makes the weary elephants

quicken their step,
the bulls give way.

The new arrivals are breeding herds
of elephants with young.

They come from the distant
Okavango Delta.

They wouldn't be here if not
for the recent rain.

All the zebra herds have now
reached the grassy plains.

They can settle in here for a few
months, and regain their strength.

For the expecting mother,
the new grass is like a gift

from the gods.

And finally she gives birth.

The rich pasture is crucial
for the mother's milk,

and her new arrival spends most
of the time suckling.

For the first few days of its life
the mother keeps her away

from the herd to imprint her unique
smell and stripe pattern.

The little one is well developed
at birth

and is following its
mother within an hour.

By 3 months it will start to drink
water and eat grass.

Intruders aren't tolerated.

The foal's mother chases
off any lost foals.

She needs to watch her
new charge closely.

Being lost here isn't wise.

The lions have been waiting
patiently for the herds to arrive.

The mother has kept her foal safe.

The pride join the hunter
and they finish the meal quickly.

A small foal doesn't last long.

As the weeks pass on the
Makgadikgadi plains the foal

follows her mother everywhere,
moving with the herd

from grass to water.

Life is much easier
for the jackals now too.

But this water is only temporary.

The jackals know they have
to make the most of summer.

Shadowing the lions
is their number one priority.

Meanwhile, the foal's mother has
carelessly dropped her guard.

The jackals are hot
on the lions' heels.

The lionesses have gone to fetch
the cubs, while the male

secures the kill.

For the scavengers, now
is the time to strike.

The vultures' plan is to
intimidate the predator.

But this ploy doesn't work
on the big male lion.

He has his hands full keeping
control of the kill.

The jackals are always
waiting for a gap.

But facing the lion isn't an option.

Eventually he sneaks a piece.

Just before the lionesses reappear.

They'd left the two month old cubs
in the den during the hunt,

and now they lead them
back to the kill.

One of the lionesses tests
the father's mood before allowing

the cubs near.

A swipe from his powerful paw
could cause a serious injury.

But he seems willing
to share his meal and he allows

the family to approach.

The cubs aren't so sure.

For the zebra foal the tragic death
of its mother is a huge loss,

but for the lion family
it's a windfall.

This carcass will keep
them fed for a week.

When the cubs have tried a little
meat, they revert to playing.

For the lions it's been
a successful day.

The ever-patient scavengers
finally get their turn.

And the jackal once again
steals from the vultures.

If the zebra foal doesn't stay
with the herd, she'll never make it.

Keeping up is her only hope.

The jackal also has
a family on the plains.

(howling)

Jackals pair for life
and they have cubs every summer.

By the time the rains bring
an abundance of insects and food,

the cubs are old enough
to catch their own.

Although they still need to learn
which of the little critters

are good to eat and which bite.

Soon the cubs will start
to follow their parents

on scavenging outings.

But that will be in
another month or so.

For now they stay
close to their den.

Groomed and cared for
by their attentive mother.

For the remainder of summer
the cycle of life unfolds

on the green plains
of the Makgadigadi.

Endless days of grazing
nourish the herds.

Stallions compete for
the favour of the females.

And the lone foal is carried along
by the herd, gaining strength.

But the rains eventually cease,
and the clouds disappear.

The grasses dry, leaving
bare, sandy patches.

Without rain to replenish
the pools, they start to dry.

The time has come for the zebras
to leave the plains.

Staying here is not an option,
soon there will be nothing for them

to eat or drink.

Their 80 mile return journey
to the pools in the dry Boteti River

will be a gruelling trip.

For the lone foal, this will be
the most difficult journey

of its life.

Some foals are smaller, but at least
they still have their mothers close.

But others already lag behind.

In baking temperatures
the zebras reach the edge

of the drying summer pastures.

The ever present vultures
track the herds, waiting

for the weak to stumble.

Within a couple of hours a dead
animal is almost stripped clean.

The lappet-faced vultures
do their job - their powerful beaks

open up the hide and
cut through the tendons,

allowing the rest of the scavengers
access to the innards.

The zebras can't slow their pace,
the more they linger,

the faster they dehydrate.

Their survival now depends on how
quickly they can reach

the Boteti River, and whether there
is still water there.

Half way through their journey
they get a lucky break,

a last pool of rain water.

But they're edgy as they drink.

Lions often wait around water.

They need to drink as quickly as
possible and be on their way again.

The dry scrubland
lies ahead of them.

It's the last obstacle
before the Boteti river,

but an old stallion
is dropping behind.

The harsh conditions separate
the strong from the weak.

Eventually, the first herd of tired
and traumatised zebras

crest the bank of the Boteti.

They walk into the river bed
where there should be flowing water.

But all they see are
the desperate hippo.

The foal has made the journey,
it's endured the most

difficult survival test.

And the youngest ones born late
in the summer are also lucky

to be alive.

But for the 20th consecutive
year, the river is dry.

But there is something these animals
don't know.

A little further upstream

a trickle is dribbling
across the hot sand.

It brings new visitors,
tiny fish ride the head

of the flood.

Slowly the stream gathers momentum.

And within hours water is charging
down the upper reaches

of the Boteti.

The flood has travelled 700
miles from the north.

An unusual amount of rain has fallen
over the mountains of neighbouring
Angola.

The waters fill the Okavango delta
to the highest recorded flood level

in 30 years.

For months, this water has crossed
the shallow gradient of the desert,

spilling out of the delta
and moving steadily south.

And as the zebra and elephant arrive
back in the dry Boteti,

these far off rains will soon be
delivering salvation.

For the first time in 20 years
the Boteti starts to flow.

Suddenly, the crocodiles that ate
nothing more than

little parcels of feathers have
something new to feast on.

(croaking)

The olive toads that hibernate
through the drought, wake up.

They never know how long the floods
will last so they waste no time

looking for a mate.

Competition is fierce,
and the highly desirable

females are mobbed.

The over enthusiastic males
sometimes drown the female.

Individuals that survive the orgy
lay as many as 25000 fertilised

eggs in long strings,
in the calm shallows of the river.

The eggs will hatch within 24 hours.

Soon, the quiet backwaters
of the Boteti writhe

with newly hatched tadpoles.

They stay in the water
and feed on algae.

An elephant footprint
can hold thousands.

The first froglets
are already emerging.

Although hundreds of thousands
make the metamorphosis,

thousands are eaten and very few
survive to become adults.

The following day, water reaches
the last Boteti pools

filling the hippos' stagnant
mud wallow to bursting point.

This year, if the cows give birth,
the dominant bull will allow

the youngsters to live.

But despite the rush of water,
the surrounding landscape

is still dry and dusty.

The remaining zebra herds
arrive at the river,

and what they find surprises them.

The oldest ones remember the last
time the Boteti was in flood.

But, for the majority, the flowing
river is a new experience.

They approach it cautiously.

But soon drop all inhibitions.

For the first time in its life,
the foal can immerse itself

in the river.

The elephants arrive too.

They have seen the floods before,
they remember them well.

The tussle for water still lives
in these creatures' minds.

But now there is no real need
for confrontation.

For the elephants, it's
a time for celebration.

For the first time in
decades, they can swim.

With so much water around, there
is plenty of space for everyone.

And by the end of winter,
rains come to the dusty Boteti.

The area greens, and the zebra
will now have grazing here too.

The river swells with the promise
of fresh water that will stay

for the year.

Eventually, the summer rains
will draw many of the animals away

from the Boteti again,
but this time the migration

will be much easier.

And they'll have a lush
paradise to come back to.

But for now, the tough drought
of the past 20 years is already

a distant memory,

and the Boteti survivors revel in
their new surroundings.

Blessed by the miracle
of the returning river.