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The first time
I visited Kenya, about 30 years ago,

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I was a stranger.

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This was the land of my father,
who had passed away and who I barely knew.

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But I met my family.

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I visited the village they had come from.

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I felt welcome everywhere.

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And as my sister and I
spent a few days on safari,

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I felt something else.

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Awe.

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At the African bush that swept on forever,
with wide open skies,

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and wildlife that never seemed to end.

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What a gift to see the world anew.

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To see the place where,
ultimately, all of us come from.

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I'd like to take you
to one special park in Kenya,

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to experience the heartbeat of Africa.

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A wilderness of boundless space,
breathtaking beauty,

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and wildlife on an epic scale.

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Tsavo National Park.

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A land where the elephants are king.

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And everyone knows it.

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In the East of Africa lies Kenya,

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home to a rich array of wildlife
and breathtaking landscapes.

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In the south is Tsavo.

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Nearly 8,500 square miles,

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it's the size of a small country,
and Kenya's largest national park.

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To the west, the unforgettable sunsets

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behind Africa's highest mountain,
Kilimanjaro.

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Lording over an ancient land of lava,

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volcanic hills,

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and sparkling oases.

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And in the east,
an endless haze of thorny scrub…

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traversed by life-giving rivers.

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Alongside them,
the shady wall of the Yatta plateau,

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one of the longest lava flows
in the world.

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And everywhere you look,

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Tsavo's iconic bright red soil
stamps its personality

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on everybody who lives
in this extraordinary wilderness.

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Tsavo is home
to Kenya's largest elephant populations.

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Over 13,000 roam freely
through this vast landscape.

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To find them,
you have to know where to look.

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Enjoying a swim,

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adolescent bulls let off some steam…

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…like synchronized swimmers
in liquid chocolate.

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It's April. The watering holes are full.

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The rains may not return
for six months or more.

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As males get older,
they prefer to go it alone.

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A few of them may go on to become
the biggest tuskers to walk the Earth.

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This is Lugard,
named by the rangers who monitor him.

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A 50-year-old "super tusker"

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and one of Kenya's national treasures.

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Each tusk alone
weighs well over 100 pounds.

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These ambassadors of the elephant world
have had to endure immense challenges…

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living through successive droughts,
modern development,

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and poaching from the illegal ivory trade.

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Today, there are believed to be just
30 super tuskers remaining across Africa.

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And Tsavo is home to a third of them.

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Most are now living well into old age.

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National parks play a vital role
in their protection.

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Over the coming months,

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Tsavo's extreme climate
will test all the animals that live here.

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Only those that have adapted
to its fast-changing conditions

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will survive the dry season.

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This hungry hornbill

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has developed an ingenious way
of getting a bigger breakfast.

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But he can't do it alone.

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A family of dwarf mongooses.

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The hornbill is ready to go,

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but they are in no rush.

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He can only wait

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while the mongooses
get ready for their day.

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They won't go anywhere
until the signal is given.

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At last, they're off.

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And right behind them,
the hungry hornbill.

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The scampering mongooses
stir up bugs in the undergrowth,

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and what they miss,

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he'll snap up,

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saving him the job
of finding his own food.

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The mongooses don't seem to mind.

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Foraging together works for everyone.

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Especially when the landscape dries up

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and there's a lack of cover.

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The hornbill acts as a lookout.

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One call sends everyone diving for cover.

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Of all the items on the menu,

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this appears to be a favorite.

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Giant African land snails,

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each up to six inches long.

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Some of the largest,
juiciest snails in the world.

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Easy to catch too.

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These snails aren't going anywhere fast.

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But they are a tough nut to crack.

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These mongooses have developed
a special technique.

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They use the wooden logs like an anvil

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to smash the snails against.

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Tsavo is one of the few places
where this behavior has been observed.

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The hornbill knows a dinner gong
when he hears one.

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The dry climate here means
this isn't an easy place to make a living.

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So working together helps ensure
they both get enough to eat

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as food becomes scarce.

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As the dry season tightens its grip
on this vast park,

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the resource that's in most urgent need

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is water.

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To protect one of Tsavo's
most critically endangered animals,

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this remote water hole
is filled by rangers.

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As evening approaches,

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the stage is set
for this shy creature to appear.

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Black rhinoceros.

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A mother and her calf.

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Using a sensitive night vision camera,
we are able to see them in color.

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Youngsters follow
their mothers' movements closely.

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They have an intense bond.

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Rhinos have poor vision at a distance…

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but an incredible sense
of hearing and smell.

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They curl their lips back
to sense who's around in the night air.

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More families arrive to take a drink.

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Dominant black rhinos
are often territorial.

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But some individuals
are more feisty than others.

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There were once around 8,000
here in Tsavo.

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In the 1970s and '80s,

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poachers killed all
but ten for their horn.

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A breeding program has since
increased the population to over 100.

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These usually solitary creatures
come to drink and socialize.

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Mothers greet friends.

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Calves meet playmates…

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…and fathers.

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But when more males arrive,
the atmosphere changes.

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During the dry season,

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unusually high numbers
of rhinos gather here.

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They have bred so successfully

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that there's now
increased competition for space…

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…and mates.

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One of the males makes his move
on the mother with her calf,

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but she gives him a clear message.

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A dominant older male
arrives at the water hole.

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Rangers call him Atoti.

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A young female.

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Too young to mate,
she's not interested in him.

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His frustration leads to hostility.

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He uses his horn to try
and hook her hind legs and trip her up.

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The other females and calves
decide it's time to go.

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The young female manages to outrun him.

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And Atoti cools off.

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As the dry season continues,

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many of the natural water sources
around the park slowly disappear.

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But there is a special place
to the north which is a permanent oasis.

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The cloud forests high in the Chyulu Hills

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rise out of the plains in Tsavo West.

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Formed from porous,
volcanic rock, they absorb rainfall,

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creating underground reservoirs.

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It takes over 20 years for the water
to seep through to the plains below…

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…where it emerges in a constant supply…

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at Mzima Springs…

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a name that means "alive" in Swahili.

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It's estimated
that over 50 million gallons

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pour from the ground every day

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into crystal-clear pools
buzzing with activity.

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Fig trees provide food
for the vervet monkeys.

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And barbel wait below for falling fruit.

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A bountiful paradise

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with enough food for everyone.

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But this magical pool

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belongs to a pod of 14 hippopotamuses,

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fiercely defended by the huge alpha male.

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He can hold his breath
for up to five minutes

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and spend more
than half his life submerged.

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Normally found in muddy pools,

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it's incredibly rare to see
the intimate lives of these shy creatures.

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Early every morning, Dad leads his family
to deeper, cooler water.

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Hippos can weigh more than a family car,

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but underwater,
they are surprisingly graceful.

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The adults sleep
during the hottest part of the day.

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The youngsters play right through it.

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And when they get too boisterous,

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the adults keep them in line.

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Without the hippos,
the diversity of life here wouldn't exist…

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because they bring something vital
to this water.

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A natural fertilizer.

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It might not do much
for the crystal-clear visibility…

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but this is the very stuff
that keeps Mzima's ecosystem thriving.

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It provides nutrients for the plants

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and food for the insects and fish…

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…who follow the hippos
for the freshest supply.

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Fresh dung isn't the only food
that hippos offer the fish here at Mzima.

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By opening his mouth,
this hippo invites the fish

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inside his huge, powerful jaws.

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They forage for scraps
stuck between his teeth,

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demonstrating an extraordinary
level of trust.

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Their rasping mouthparts
also clean the hippos' hide,

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their toenails, their cracked feet,
and all those important places.

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A full meal in exchange
for a pedicure and polish.

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The small green oasis at Mzima Springs

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provides water to the fortunate animals
who live in this corner of the park.

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But it's a different story
for those who roam across its arid center.

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Elephants have incredible memories,

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guiding them to areas where they've found
food and water in previous dry seasons.

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But in the middle of the park,
they face a daunting obstacle.

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Tsavo was established in two parts,

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East and West,

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sliced down the middle
by an existing road and railway.

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The busy road is now
a dangerous barrier for wildlife

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moving between the two parks.

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In 2017, a new railway was completed
alongside the old one,

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linking Kenya's largest port, Mombasa,
and her capital, Nairobi.

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The steep embankments and fences prevent
the animals from crossing the tracks,

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restricting their movements.

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They can only reach the other side
via specially-built underpasses.

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Some of the elephants are brave enough
to make it through the obstacles.

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Across Africa,
there's a boom in infrastructure

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that is affecting its wild places.

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It's why the size
of Tsavo is so important.

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It's big enough
to offer alternative feeding grounds.

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But it's not only the larger animals
that travel huge distances

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at this time of year.

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It's July, Tsavo's driest month.

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On the parched plains to the east,

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a male sandgrouse and his mate
are raising their family.

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As ground-nesting birds,
these newly hatched chicks

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will get up and walk within hours.

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With temperatures reaching
up to 100 degrees Fahrenheit,

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they must find shade
and a safe hiding place.

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Their father faces an urgent challenge.

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Find drinking water,

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or his chicks will die.

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He joins a flock of other sandgrouse,

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all in desperate search of the same thing.

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They will fly up to 20 miles away…

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to the mighty Galana River.

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It's a lifeline for the animals

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as the dry season really bites.

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The sandgrouse come here
in huge numbers at this time of year.

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At the water's edge, there are threats.

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Keeping close to his flock means
that hundreds of eyes keep a lookout.

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He can hold up
to two tablespoons in his throat,

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but it isn't enough for his three chicks.

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He wades in a little further

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for a remarkable trick.

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Rocking backwards and forwards,

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he absorbs water into his breast feathers.

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Their specially-adapted spiral shape
soak up water like a sponge.

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Fifteen minutes to fill up, and he's off…

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flying home fully-laden with water.

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One by one,
the birds peel off from their flock.

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-He calls to his mate.

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She guides him to where
she's hidden their thirsty chicks.

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Dad to the rescue.

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Desperate for a drink,
the chicks crowd their father,

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stripping precious water
from his feathers with their beaks.

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He will make
this arduous journey every day

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for the next two months…

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until the chicks are big enough
to make the flight to water themselves.

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00:30:03,400 --> 00:30:05,640
In recent years, Kenya's climate

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00:30:05,720 --> 00:30:08,720
has become less predictable
and more extreme.

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00:30:15,600 --> 00:30:17,400
It's the height of the dry season,

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00:30:18,520 --> 00:30:20,040
and there's no end in sight.

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00:30:24,800 --> 00:30:29,000
Some have found a way
to find the few remaining green leaves.

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00:30:30,000 --> 00:30:32,280
The gerenuk tiptoes for a nibble.

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00:30:33,560 --> 00:30:36,160
They may go their whole lives
without drinking water.

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00:30:39,120 --> 00:30:41,040
Nicknamed the "giraffe gazelle,"

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00:30:41,760 --> 00:30:45,320
they rely on acrobatics
and their long necks

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00:30:45,400 --> 00:30:48,920
to reach succulent leaves
that other grazers cannot.

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00:30:51,880 --> 00:30:53,840
Even for them, it's slim pickings.

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00:30:59,680 --> 00:31:03,680
Tsavo's red earth is sucked upwards
in the swirling dust devils.

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00:31:09,960 --> 00:31:11,840
Larger animals, like the buffalo,

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00:31:12,360 --> 00:31:14,920
have to keep moving
to find food and water.

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00:31:21,920 --> 00:31:25,080
The herds join up, over a thousand strong.

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00:31:32,880 --> 00:31:36,920
They head towards the Galana River,
which flows year-round.

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00:31:47,440 --> 00:31:51,720
Stragglers will be picked off
by Tsavo's most infamous predators.

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00:32:05,040 --> 00:32:08,920
When the old railway was built,
more than 120 years ago,

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00:32:09,000 --> 00:32:12,240
this territory was terrorized
by two lions…

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00:32:14,520 --> 00:32:17,200
known as the "Man-eaters of Tsavo."

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00:32:21,520 --> 00:32:22,400
Legend has it

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00:32:23,280 --> 00:32:26,680
they devoured 135 railway workers,

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00:32:28,320 --> 00:32:30,520
though the true figure
is probably far lower.

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00:32:32,360 --> 00:32:33,760
Famous for their mohawks,

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00:32:34,360 --> 00:32:36,480
a trait shared by their descendants today.

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00:32:40,560 --> 00:32:44,760
Their looks are thought to have been
shaped by the thick scrub they live in.

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00:32:48,000 --> 00:32:52,000
This shorter mane is less likely to snare
on the thorny undergrowth.

278
00:32:53,600 --> 00:32:55,840
It also keeps them cooler in the heat.

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00:33:00,360 --> 00:33:03,920
But even the toughest predator
struggles at this time of year.

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00:33:20,120 --> 00:33:24,480
The pride's water hole
has become a pool of sticky mud.

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00:33:29,720 --> 00:33:33,200
Many of their prey
have left to find water elsewhere.

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00:33:35,040 --> 00:33:38,200
These last dregs
will sustain them for now.

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00:33:54,320 --> 00:33:56,400
Across the dry plains of Tsavo East,

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00:33:57,280 --> 00:34:02,960
a group of bull elephants head toward
the remote northern reaches of the park.

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00:34:11,720 --> 00:34:15,680
This is the most wild
and inaccessible area.

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00:34:24,040 --> 00:34:27,680
Vast, rocky monoliths,
millions of years old,

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00:34:28,280 --> 00:34:30,800
rise from the dry, thorny scrub.

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00:34:45,280 --> 00:34:49,080
Each elephant remembers routes
they have taken through the years…

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00:34:53,880 --> 00:34:56,040
passed down through generations.

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00:35:00,160 --> 00:35:03,600
Their well-trodden trails
are visible from the air,

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00:35:05,080 --> 00:35:07,800
creating a network
through the barren landscape.

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00:35:22,000 --> 00:35:24,760
Large bulls can go several days
without a drink,

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00:35:25,920 --> 00:35:31,200
allowing them to travel huge distances
across drought-stricken bush.

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00:35:39,600 --> 00:35:44,000
They have staked their lives
on finding water when they arrive.

295
00:35:47,400 --> 00:35:49,880
But the Tiva River has run dry.

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00:35:51,760 --> 00:35:54,360
Now, it's just a river of sand.

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00:35:58,320 --> 00:36:00,280
Not a drop of water in sight.

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00:36:04,160 --> 00:36:08,560
But the doum palms that flank
this seasonal river are still green,

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00:36:09,560 --> 00:36:12,680
suggesting there is water here somewhere.

300
00:36:24,680 --> 00:36:27,160
And the wise old bulls
know how to find it.

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00:36:50,840 --> 00:36:53,120
Elephants have
an incredible sense of smell.

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00:36:54,000 --> 00:36:58,680
Millions of receptors in their trunks
help guide them to water many miles away,

303
00:37:00,920 --> 00:37:05,360
and they can even sense it when
it's buried several feet beneath the sand.

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00:37:14,880 --> 00:37:17,080
To get to it, they must dig.

305
00:37:22,680 --> 00:37:26,720
As these wells become deeper,
the groundwater seeps in.

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00:37:31,320 --> 00:37:33,880
Their trunk acts as a flexible straw,

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00:37:34,560 --> 00:37:36,480
sucking up the sandy water.

308
00:37:40,720 --> 00:37:45,160
It seems they allow the sediment
to sink down their trunks and separate,

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00:37:47,120 --> 00:37:48,040
then blow it out.

310
00:38:03,480 --> 00:38:06,280
And enjoy pure, filtered water.

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00:38:20,880 --> 00:38:24,440
Tantalizing for those watching
from the sidelines.

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00:38:36,520 --> 00:38:40,720
Once they've had their fill,
the audience gets to take their turn.

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00:38:42,480 --> 00:38:45,480
Baboons, always the first to the bar.

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00:38:55,360 --> 00:38:59,520
Further down the course
of the Tiva lies Bisadi waterfall.

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00:39:01,000 --> 00:39:04,520
Dry, except for a few precious pools.

316
00:39:07,080 --> 00:39:08,320
It's eerily silent…

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00:39:12,600 --> 00:39:15,040
until dawn breaks.

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00:39:32,120 --> 00:39:35,880
It's as if the entire canyon
comes under a spell.

319
00:39:38,680 --> 00:39:39,920
Red-billed quelea,

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00:39:40,840 --> 00:39:44,360
the world's most abundant
wild bird species.

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00:39:49,400 --> 00:39:50,240
It's September.

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00:39:50,760 --> 00:39:52,160
As water sources dwindle,

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00:39:52,760 --> 00:39:57,680
these nomadic super-colonies
gather here in their millions.

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00:40:17,360 --> 00:40:18,840
With mesmerizing rhythm,

325
00:40:19,720 --> 00:40:24,240
they drink from these last pools of water,
one beakful at a time.

326
00:40:31,920 --> 00:40:34,800
This mass migration builds and builds

327
00:40:35,440 --> 00:40:37,360
towards the end of the dry season.

328
00:40:46,400 --> 00:40:48,040
Creating chaos by the water,

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00:40:49,320 --> 00:40:52,240
they spook anyone else
who dares to drink here.

330
00:41:16,720 --> 00:41:20,760
Their sheer numbers
bend the branches of surrounding trees.

331
00:41:27,000 --> 00:41:28,800
They are prisoners to this place

332
00:41:29,960 --> 00:41:32,480
for as long as the water lasts.

333
00:41:54,800 --> 00:41:58,320
The air is heavy with anticipation.

334
00:42:03,920 --> 00:42:07,040
Then, a symbol of hope.

335
00:42:09,520 --> 00:42:11,040
In the parched landscape,

336
00:42:11,120 --> 00:42:16,720
the baobab trees throw out green leaves
and extravagant white flowers.

337
00:42:22,680 --> 00:42:24,360
Change is in the air.

338
00:42:27,360 --> 00:42:29,000
And everyone can sense it.

339
00:42:38,120 --> 00:42:40,240
And finally in October,

340
00:42:40,320 --> 00:42:42,640
after six months of absence,

341
00:42:44,240 --> 00:42:45,120
rain…

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00:42:47,400 --> 00:42:50,680
building in the hills
and mountains of Tsavo West

343
00:42:52,120 --> 00:42:55,080
and on the plains in Tsavo East.

344
00:43:19,040 --> 00:43:22,360
The dry, sandy Tiva flows again.

345
00:43:26,080 --> 00:43:29,520
Cascading over Bisadi canyon,
where the quelea drank,

346
00:43:30,520 --> 00:43:32,680
the waterfall comes alive.

347
00:44:14,120 --> 00:44:17,560
For the next few weeks,
this river will keep flowing,

348
00:44:18,160 --> 00:44:19,760
rejuvenating the land.

349
00:44:41,320 --> 00:44:43,560
The drama turns to relief.

350
00:44:46,200 --> 00:44:49,480
From barren desert to painted paradise.

351
00:44:51,760 --> 00:44:54,880
It's the extremes in Tsavo
that are so magical.

352
00:44:59,640 --> 00:45:01,440
Rinsed of its red dust,

353
00:45:02,120 --> 00:45:06,080
morning glory smothers the park
with her floral carpet.

354
00:45:12,240 --> 00:45:16,200
And a blizzard
of pioneer white butterflies arrive.

355
00:45:20,680 --> 00:45:24,640
Millions fill the skies
on a journey towards the coast.

356
00:45:31,120 --> 00:45:32,760
Like a winged relay race,

357
00:45:32,840 --> 00:45:35,840
new generations emerge
with the fresh growth

358
00:45:35,920 --> 00:45:38,440
and continue the journey
their parents started.

359
00:45:49,160 --> 00:45:53,800
Dancing across the flowers,
these huge swarms in the wet season

360
00:45:53,880 --> 00:45:56,440
are vital for the productivity
of the park…

361
00:46:01,040 --> 00:46:02,240
pollinating as they go

362
00:46:03,120 --> 00:46:06,200
and providing an easy meal
for insect-eaters.

363
00:46:17,600 --> 00:46:18,720
There's time to play…

364
00:46:25,480 --> 00:46:28,160
…and raise the next generation.

365
00:46:30,320 --> 00:46:31,200
A baby boom.

366
00:46:34,200 --> 00:46:37,800
Living evidence that when it comes
to protecting wilderness,

367
00:46:38,720 --> 00:46:39,960
size matters.

368
00:46:45,800 --> 00:46:50,160
The bigger the park,
the more species will call it home.

369
00:46:51,920 --> 00:46:55,560
The larger the gene pool,
the healthier the animals.

370
00:47:00,720 --> 00:47:04,600
In recent years,
landowners surrounding Tsavo National Park

371
00:47:04,680 --> 00:47:08,920
have joined forces to create
the wider Tsavo Conservation Area,

372
00:47:09,520 --> 00:47:11,680
doubling the protected wild space

373
00:47:11,760 --> 00:47:16,040
and allowing animals
to roam in safety beyond its borders.

374
00:47:25,440 --> 00:47:29,760
It's only by continuing to protect
vast wilderness areas like Tsavo

375
00:47:29,840 --> 00:47:32,840
and creating new parks of similar scale

376
00:47:32,920 --> 00:47:37,240
that we can secure a future
for nature on this planet.