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This is the Okavango Delta

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in Southern Africa.

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An inland ocean...

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..peppered with a thousand islands.

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Some are large...

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others small.

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Here, the sun battles water
for control.

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Worlds are created...

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then taken away.

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To survive,

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all must cope...

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with a state of never-ending change.

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From the Arctic...
(POLAR BEAR GROWLS)

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..to the tropics...

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..islands are wild laboratories...

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..where unique rules apply...

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..and nature puts life...

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..to the ultimate test.

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In the heart of Southern Africa...

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lies the Okavango Delta.

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An oasis in the desert.

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At its heart
are the permanent waters.

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These sit along vast, flat plains.

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At its farthest reaches
are the dry borderlands.

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Every year,
water surges down the rivers,

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fanning out over the desert.

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Islands emerge magically
from the sand...

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..and the largest is Chief's Island.

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The delta's waters
are constantly changing.

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It's now at peak flood...

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and Chief's Island
is brimming with animals.

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(ANIMALS CHITTER)

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This is where a hyena clan...

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..has chosen to carve out
a territory.

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(CUB SQUEALS)

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They have a queen
who rules over the clan.

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Under her leadership,
they're a stable, social unit

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that keeps everyone fed.

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They're the largest hyena clan
on the island;

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over 40 individuals.

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They need this large family.

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Their island is rich in prey,
but also rivals...

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(LOW GROWLING)

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(CUBS SQUEAL IN DISTANCE)

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..all of them vying for control...

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..of this prime hunting ground.

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Every day,
scouting parties strike out

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in the search for food.

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(HYENAS WHOOPING)

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But there's more
than just food to be found.

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Hyenas welcome the floods.

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They love playing in water...

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..and these two young sisters...

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take full advantage.

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(HYENAS CACKLING)

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Distracted, they haven't noticed

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the rest of the clan has moved on...

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(HYENAS WHINING)

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..and they are alone.

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Without backup...

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..they're in danger.

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A large pack of wild dogs
has spotted them.

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(DOG SNORTS)

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Wild dogs and hyenas
are mortal enemies.

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(UNSETTLING MUSIC BUILDS)

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So, when dogs outnumber them...

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..they'll teach them a lesson.

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(HYENA CHITTERS)

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(DOG GROWLS)

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The sisters can match them for speed

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but not stamina...

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(DOG GROWLS)

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..and they've been separated.

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(HYENA SQUEALS)

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(DOGS GROWL)

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One manages to hold them off...

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(HYENA SQUEALING)

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..so they turn on her smaller sister.

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(GROWLING)

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(DOG BARKS)

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(HYENA SQUEALS)

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It's only the crushing power
of her jaws...

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..that makes them think twice.

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Point made, the dogs lose interest.

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Off to harass someone else.

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In the future, the sisters must stay
closer to the safety of the clan.

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(HYENA SQUEALS)

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(CUB GROWLING)

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Back at their island den,

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the rest of the family
are enjoying a feast.

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(CHOMPING)

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But tougher times lie ahead.

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Soon, the waters
around Chief's Island will fall,

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and prey will be free to leave.

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Finding food for this large family...

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..will become a challenge.

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(WIND WHISTLES)

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The delta,
on which all the animals depend,

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is a result of geological events

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set in motion millions of years ago.

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(THUNDER CRACKS)

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Beneath the desert,

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Africa started to tear itself apart.

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Huge chunks of rock collapsed,

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creating a depression.
(ROCK CRACKING)

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Rivers filled it with sand...

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..eventually forming the wide,
flat delta we see today.

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(WIND WHISTLES)

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Every year, these vast plains are
covered with flood water...

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..revealing thousands of islands.

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Some are tiny...

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..others larger,

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but many have one thing in common.

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They owe their existence
to some of the tiniest of creatures.

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(SINISTER MUSIC)

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Termites.

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They quietly labour...

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..building a city made of soil.

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Deep within is something remarkable.

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(OMINOUS MUSIC)

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The beating heart of the colony.

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(TERMITE QUEEN'S BODY SQUELCHES)

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This is the termite queen.

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She's so large, she's helpless...

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..so is cleaned and fed
by her devoted workers.

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She might be 20 years old.

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Her destiny is to reproduce...

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..laying 20,000 eggs every day.

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Most will become new workers
for the colony.

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They have a special task.

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These tiny insects
are island engineers.

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(FUTURISTIC ELECTRONIC MUSIC)

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They build,

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one mouthful of soil at a time...

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..glued together
with their own saliva.

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The termites collect more
and more soil...

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..a quarter of a tonne a year.

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They create a giant mound...

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..rising clear of the water.

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But this is only the first act.

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As weather erodes the soil...

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..a platform is created
on which more mounds can grow.

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Over hundreds of years,

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mounds rise, fall,

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and rise again.

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An island slowly takes shape...

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..eventually...

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..becoming huge.

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These islands, created by some
of the smallest creatures...

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..are home to some
of the largest animals on Earth.

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(ELEPHANT GRUNTS)

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Over the last few weeks...

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..the delta's waters
have been falling.

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Chief's Island has now disappeared.

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And so, times have changed
for the hyena clan.

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Gone are the days of easy pickings.

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Their prized island has withdrawn
its greatest benefit.

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Before, prey animals were trapped
by high water.

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But now, they're free
to escape the hyenas.

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Being the biggest, baddest clan
is an asset in the good times...

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..but now they're just
extra mouths to feed.

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Finding enough food
is their full-time job.

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Hyenas have an acute sense
of smell...

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(HYENA SNIFFS)

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..giving them the edge
over other predators.

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And there's a scent on the breeze.

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(HYENA CACKLES)

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A zebra...
(HYENAS CHITTERING)

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..or what's left of it.

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(HYENAS CHITTERING)

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Hyenas are the island's recyclers.

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Unlike their rivals,

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they can digest skin
and even solid bone.

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(CRUNCHING)

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But the clan is being watched...

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..by the zebra's rightful owner.

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(DEEP GROWLING)

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(LION GROWLS)

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(HIGH-PITCHED YAPPING)

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A male lion can snap a hyena's spine
with one bite,

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so this is a life-or-death gamble.

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(HIGH-PITCHED YAPPING)

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(LION GRUNTS)

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But the hyenas have numbers
on their side.

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They can create chaos and confusion.

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(LION ROARING)

187
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(HYENA YAPPING)

188
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(LION GROWLING)

189
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(HYENA WHINES)

190
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(LION ROARS)

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(DRAMATIC MUSIC)

192
00:14:08,040 --> 00:14:10,040
(MUSIC INTENSIFIES)

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(MUSIC FADES)

194
00:14:14,760 --> 00:14:16,160
(GROWLS)

195
00:14:16,200 --> 00:14:18,120
(HYENAS CACKLING)

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The lion can't chase them all.

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He'll bide his time.

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00:14:32,760 --> 00:14:36,160
Hyenas better watch out.

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(GROWLS)

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(HYENAS WHOOPING IN DISTANCE)

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For the hyenas,
this will keep them going.

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00:14:50,560 --> 00:14:54,920
Their ability to survive
on skin and bones

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means there's even enough
to take back to the den.

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00:15:01,760 --> 00:15:03,520
(CUBS SQUEAKING)

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00:15:18,520 --> 00:15:20,400
The hyenas are getting by...

206
00:15:21,800 --> 00:15:24,520
..but until the delta brings change,

207
00:15:25,520 --> 00:15:28,120
..their future hangs in the balance.

208
00:15:30,760 --> 00:15:33,440
In the farthest reaches of the delta,

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the water is now almost gone.

210
00:15:38,360 --> 00:15:40,240
After six months of flood...

211
00:15:41,360 --> 00:15:44,480
..the desert is reclaiming its sands.

212
00:15:54,960 --> 00:15:57,800
These are the borderlands.

213
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Food is scarce.

214
00:16:07,440 --> 00:16:09,280
This barren landscape...

215
00:16:10,400 --> 00:16:14,080
..was once a lush, green place.

216
00:16:14,120 --> 00:16:17,080
(SWELLING ORCHESTRAL MUSIC)

217
00:16:21,200 --> 00:16:24,360
Now there's little more
than rutted dirt.

218
00:16:33,480 --> 00:16:38,440
A lone bull hippo
is left high and dry...

219
00:16:44,640 --> 00:16:47,640
..using the mud to protect his skin

220
00:16:47,680 --> 00:16:49,840
from the beating sun.

221
00:16:53,360 --> 00:16:55,760
But some...

222
00:16:56,760 --> 00:16:59,280
..have been waiting
for this opportunity.

223
00:16:59,320 --> 00:17:01,320
(ETHEREAL MUSIC)

224
00:17:12,760 --> 00:17:14,560
For trapped fish...

225
00:17:16,160 --> 00:17:18,200
..there's no escape.

226
00:17:21,320 --> 00:17:24,840
Pelicans and storks fly in
from afar...

227
00:17:26,360 --> 00:17:29,440
..for a final grisly feast.

228
00:17:38,040 --> 00:17:41,720
Soon, even they'll be forced
to leave.

229
00:17:42,880 --> 00:17:46,320
Unlike the fish,
they have somewhere to go.

230
00:17:48,600 --> 00:17:50,680
(GRUNTING)

231
00:17:52,760 --> 00:17:56,200
Upstream, the hippos
are in better shape.

232
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They don't know what's coming.

233
00:18:00,400 --> 00:18:03,640
Their lagoon is already shrinking...

234
00:18:05,040 --> 00:18:08,680
..and it's causing tempers to flare.

235
00:18:08,720 --> 00:18:10,840
(ROARING)

236
00:18:27,560 --> 00:18:32,320
An old male leaves the stresses
of the water to feed.

237
00:18:33,760 --> 00:18:35,320
(HIPPO SNORTS)

238
00:18:35,360 --> 00:18:39,520
There's still good grazing to be had
around the edges of the lagoon.

239
00:18:41,760 --> 00:18:43,760
But he's not alone;

240
00:18:43,800 --> 00:18:45,760
a young pretender,

241
00:18:45,800 --> 00:18:49,400
eager to find their place
in the pecking order.

242
00:18:50,360 --> 00:18:52,920
The old boy's not impressed.

243
00:18:53,960 --> 00:18:55,760
(ROARS)

244
00:18:58,280 --> 00:19:00,280
(TENSE MUSIC)

245
00:19:07,760 --> 00:19:10,200
He gives a final warning...

246
00:19:10,240 --> 00:19:13,000
(GRUNTING)

247
00:19:13,040 --> 00:19:15,160
(BELLOWING)

248
00:19:15,200 --> 00:19:17,200
(GRUNTING)

249
00:19:23,520 --> 00:19:26,080
..but it's foolishly ignored.

250
00:19:26,960 --> 00:19:29,360
(FIERCE ROARING)

251
00:19:29,400 --> 00:19:31,400
(DRAMATIC MUSIC)

252
00:19:36,720 --> 00:19:38,720
(ROARING)

253
00:19:41,440 --> 00:19:43,960
(BIRD SQUAWKS)

254
00:19:45,440 --> 00:19:49,760
Times can be tough living
in these ever-shifting waters.

255
00:19:51,480 --> 00:19:54,400
Some face the changes head-on.

256
00:19:55,520 --> 00:19:58,120
Others are forced to leave.

257
00:20:14,240 --> 00:20:18,440
In the north of the delta
are its permanent headwaters.

258
00:20:19,640 --> 00:20:21,960
They never dry out.

259
00:20:22,000 --> 00:20:24,080
(WATER BUBBLING)

260
00:20:24,120 --> 00:20:27,760
Millions of fish fry have arrived,

261
00:20:27,800 --> 00:20:30,840
fleeing the receding flood
downstream.

262
00:20:32,480 --> 00:20:36,080
The maze of channels
seems to offer safety.

263
00:20:39,680 --> 00:20:41,360
What they don't know...

264
00:20:42,400 --> 00:20:45,080
..is others are arriving, too.

265
00:20:48,640 --> 00:20:50,440
A barbel.

266
00:20:53,600 --> 00:20:55,440
A voracious predator,

267
00:20:55,480 --> 00:20:58,600
over a metre long.

268
00:20:59,680 --> 00:21:01,280
And it's not alone.

269
00:21:06,000 --> 00:21:08,200
Following along behind...

270
00:21:09,400 --> 00:21:11,440
..are hundreds more.

271
00:21:15,960 --> 00:21:19,200
They scour the creeks
for unwary prey.

272
00:21:20,120 --> 00:21:22,360
The thrashing attracts
other predators.

273
00:21:24,640 --> 00:21:26,320
Egrets.

274
00:21:27,320 --> 00:21:30,960
The fish fry are forced
to run the gauntlet,

275
00:21:31,000 --> 00:21:33,840
above and below.

276
00:21:37,880 --> 00:21:39,880
(OMINOUS MUSIC)

277
00:21:41,080 --> 00:21:43,600
They're trapped.

278
00:21:54,080 --> 00:21:58,440
Gaping mouths
and stabbing beaks are everywhere.

279
00:22:03,640 --> 00:22:05,680
(CHILLING MUSIC)

280
00:22:18,760 --> 00:22:21,080
For the fish
that do make it to safety...

281
00:22:22,400 --> 00:22:25,160
..these permanent waters
offer a lifeline.

282
00:22:27,320 --> 00:22:29,800
They have survived their trial,

283
00:22:29,840 --> 00:22:33,600
but other animals are about
to face their own.

284
00:22:39,880 --> 00:22:41,640
(INSECTS CHIRPING)

285
00:22:51,040 --> 00:22:53,720
On the dry floodplains,

286
00:22:53,760 --> 00:22:55,840
the time has arrived...

287
00:22:57,960 --> 00:22:59,960
..for a magical event.

288
00:23:01,520 --> 00:23:04,200
This is when the termites breed.

289
00:23:05,720 --> 00:23:08,240
A chance to start a colony,

290
00:23:08,280 --> 00:23:11,960
and the first steps
in creating a new island.

291
00:23:13,480 --> 00:23:18,200
The next generation of winged lovers
takes to the air,

292
00:23:18,240 --> 00:23:19,920
looking for a mate.

293
00:23:21,920 --> 00:23:25,280
But it's a hostile world
outside their mound.

294
00:23:27,120 --> 00:23:30,440
As soon as they touch down,
they shed their wings.

295
00:23:32,480 --> 00:23:34,720
They must move quickly.

296
00:23:34,760 --> 00:23:36,640
Exposed on the surface,

297
00:23:36,680 --> 00:23:38,600
they're in danger.

298
00:23:41,360 --> 00:23:45,560
The males begin a frantic search
for pheromone trails...

299
00:23:46,640 --> 00:23:49,320
..chemical messages leading
to the females.

300
00:23:50,680 --> 00:23:54,040
The odds, however,
are stacked against them.

301
00:23:55,560 --> 00:24:00,040
This bumbling protein buffet
is bound to attract attention.

302
00:24:04,800 --> 00:24:06,560
Marabou storks.

303
00:24:07,680 --> 00:24:10,640
The termites are a welcome,
if unexpected...

304
00:24:10,680 --> 00:24:12,320
breakfast.

305
00:24:13,760 --> 00:24:15,760
(QUIRKY MUSIC)

306
00:24:23,520 --> 00:24:28,360
Sand toads wake from hibernation
to join in.

307
00:24:39,560 --> 00:24:43,160
Even ants take care
of the stragglers.

308
00:24:50,560 --> 00:24:55,280
He's avoided being eaten
and found what he hopes will be...

309
00:24:56,280 --> 00:24:57,960
..his new queen.

310
00:24:58,880 --> 00:25:01,480
Now, he must keep up...

311
00:25:02,520 --> 00:25:06,480
..moving as quickly as they can
to find what they're looking for...

312
00:25:10,040 --> 00:25:11,960
..soft ground.

313
00:25:17,720 --> 00:25:20,200
Then, without delay,

314
00:25:20,240 --> 00:25:22,560
they dig their marital burrow...

315
00:25:27,200 --> 00:25:29,760
..which, in the coming years...

316
00:25:31,400 --> 00:25:33,400
could become part...

317
00:25:34,360 --> 00:25:36,760
..of a new Okavango island.

318
00:25:43,920 --> 00:25:46,120
After months of drying out,

319
00:25:46,160 --> 00:25:49,200
the delta is shifting.

320
00:25:49,240 --> 00:25:52,080
Change is on the way.

321
00:25:53,080 --> 00:25:58,560
New floodwater is finally flowing
through its veins once more.

322
00:26:01,280 --> 00:26:03,360
First a trickle.

323
00:26:05,720 --> 00:26:07,640
Then...

324
00:26:07,680 --> 00:26:09,520
a flood.

325
00:26:14,480 --> 00:26:20,920
The water will reclaim over 8,000
square kilometres of desert

326
00:26:20,960 --> 00:26:24,480
and restore thousands of islands.

327
00:26:24,520 --> 00:26:26,520
(TRIUMPHANT MUSIC BUILDS)

328
00:26:42,960 --> 00:26:46,040
With it come animals...

329
00:26:49,200 --> 00:26:50,920
(LOW GROWLING)

330
00:26:50,960 --> 00:26:54,080
(ELEPHANTS SNORTING)

331
00:26:54,120 --> 00:26:56,680
.in their thousands...

332
00:26:56,720 --> 00:26:59,200
(BIRDS CHIRPING AND HONKING)

333
00:26:59,240 --> 00:27:02,320
..making the most of fresh grass.

334
00:27:08,080 --> 00:27:10,080
(UPLIFTING MUSIC)

335
00:27:20,080 --> 00:27:24,960
On Chief's Island,
the flood is back once more.

336
00:27:26,680 --> 00:27:30,240
The rising water
has rebuilt the island.

337
00:27:31,320 --> 00:27:35,080
The hyenas' prime territory
is restored.

338
00:27:41,360 --> 00:27:44,080
There's also been a baby boom.

339
00:27:45,360 --> 00:27:48,800
This couldn't happen
in the borderlands or beyond.

340
00:27:50,320 --> 00:27:52,640
Hungry youngsters are everywhere.

341
00:27:52,680 --> 00:27:54,880
And there are more to come.

342
00:27:57,840 --> 00:27:59,840
The clan queen...

343
00:28:00,920 --> 00:28:02,880
..is also expecting.

344
00:28:05,040 --> 00:28:08,040
With so many extra mouths to feed...

345
00:28:08,960 --> 00:28:12,880
..scavenging is now a full-time job.

346
00:28:21,120 --> 00:28:24,520
Being pregnant doesn't mean
she's excused duties.

347
00:28:28,160 --> 00:28:30,120
So, she sets out,

348
00:28:30,160 --> 00:28:33,320
playing her part
in the search for food.

349
00:28:37,040 --> 00:28:39,080
(SNIFFING)

350
00:28:39,120 --> 00:28:42,000
She's picked up
an unmistakable scent.

351
00:28:42,040 --> 00:28:44,120
(SNIFFING)

352
00:28:44,160 --> 00:28:46,160
(FLIES BUZZING)

353
00:28:46,200 --> 00:28:50,040
Disease has taken its toll
on elephants,

354
00:28:50,080 --> 00:28:53,520
weakened by the long dry season.

355
00:28:53,560 --> 00:28:55,720
(FLIES BUZZING)

356
00:28:55,760 --> 00:28:57,760
It's also attracted...

357
00:28:57,800 --> 00:29:00,360
unwelcome visitors.
(BIRD SQUAWKS)

358
00:29:03,600 --> 00:29:05,560
(SQUAWKING)

359
00:29:05,600 --> 00:29:07,360
Vultures...

360
00:29:07,400 --> 00:29:09,800
(HYENA GROWLS)
(VULTURE SQUAWKS)

361
00:29:11,320 --> 00:29:14,400
..a signal to every predator around

362
00:29:14,440 --> 00:29:16,720
that there's a feast to be had.

363
00:29:21,840 --> 00:29:24,600
An old foe returns.

364
00:29:27,200 --> 00:29:29,200
(LOW GROWLING)

365
00:29:32,960 --> 00:29:34,960
(VULTURES SQUAWK)

366
00:29:37,160 --> 00:29:39,000
(LOW RUMBLING GROWL)

367
00:29:39,040 --> 00:29:41,040
(OMINOUS MUSIC)

368
00:29:56,640 --> 00:30:00,040
If he catches her,
he could easily kill her.

369
00:30:02,600 --> 00:30:04,280
(LION GROWLS)

370
00:30:06,800 --> 00:30:08,960
(VULTURE SQUAWKS)

371
00:30:12,400 --> 00:30:14,600
But she isn't giving up.

372
00:30:16,040 --> 00:30:19,320
Her unborn cubs need her to succeed.

373
00:30:25,200 --> 00:30:27,160
(LION ROARS)

374
00:30:31,600 --> 00:30:34,360
But she doesn't have numbers
on her side...

375
00:30:35,360 --> 00:30:36,880
..yet.

376
00:30:39,880 --> 00:30:43,000
She calls for backup.
(HYENA WHOOPS)

377
00:30:44,360 --> 00:30:46,680
(HYENA WHOOPS)

378
00:30:48,120 --> 00:30:51,360
(HYENA WHOOPING)

379
00:30:51,400 --> 00:30:54,120
Her whoop is a call to arms.

380
00:30:54,160 --> 00:30:56,960
(HYENA WHOOPS)

381
00:30:57,000 --> 00:30:59,320
(HYENA WHOOPING)

382
00:31:04,400 --> 00:31:06,560
Clan Hyena mobilises.

383
00:31:06,600 --> 00:31:08,600
(DRAMATIC MUSIC)

384
00:31:22,560 --> 00:31:26,000
The tables have turned.

385
00:31:31,160 --> 00:31:32,880
(HYENA WHOOPING IN DISTANCE)

386
00:31:32,920 --> 00:31:36,160
Now it's the lion who's in trouble.

387
00:31:40,960 --> 00:31:42,960
(BIRDS CHIRPING)

388
00:31:44,200 --> 00:31:46,160
(HYENA SHRIEKS)

389
00:31:58,200 --> 00:32:00,200
(LION ROARS)

390
00:32:03,480 --> 00:32:05,720
This could have been a bloodbath...

391
00:32:06,960 --> 00:32:09,600
..but the delta
has delivered for both.

392
00:32:10,600 --> 00:32:12,960
There's more than either
could possibly eat.

393
00:32:14,160 --> 00:32:16,160
(HYENAS YIPPING)

394
00:32:17,920 --> 00:32:20,720
In a moment rarely witnessed,

395
00:32:20,760 --> 00:32:24,520
they settle for an uneasy truce.

396
00:32:41,320 --> 00:32:43,320
(HYENAS SLURPING)

397
00:32:46,080 --> 00:32:50,200
The queen of Chief's Island
can feed in safety for now.

398
00:32:55,680 --> 00:32:58,000
And inside her,

399
00:32:58,040 --> 00:33:02,240
the next in line to the island throne
will grow strong.

400
00:33:20,040 --> 00:33:24,840
In the floodplains, returning water
is consuming the land.

401
00:33:31,240 --> 00:33:33,280
Some animals welcome it...

402
00:33:34,400 --> 00:33:36,720
..but it's not good news
for everyone.

403
00:33:38,600 --> 00:33:41,440
It's forcing baboons
to find a new home.

404
00:33:50,120 --> 00:33:53,120
The delta's largest primate,

405
00:33:53,160 --> 00:33:57,120
they must find an island
that can support the family of 15.

406
00:34:03,840 --> 00:34:07,320
If there's one thing
the delta isn't short of now...

407
00:34:08,320 --> 00:34:10,000
..it's islands.

408
00:34:11,000 --> 00:34:14,880
And this one has its own fruit tree.

409
00:34:21,040 --> 00:34:23,440
This is just what they're after.

410
00:34:27,040 --> 00:34:28,720
Figs.

411
00:34:31,480 --> 00:34:34,200
the delta's superfood.

412
00:34:38,880 --> 00:34:43,920
But youngsters are more interested
in their new playground.

413
00:34:47,800 --> 00:34:49,800
(BABY BABOONS CHATTERING)

414
00:34:59,640 --> 00:35:01,640
The baboons can relax...

415
00:35:02,880 --> 00:35:04,840
..but below...

416
00:35:06,520 --> 00:35:09,560
..the termites are on full alert.

417
00:35:09,600 --> 00:35:11,600
(QUEEN TERMITE'S BODY SQUELCHES)

418
00:35:19,080 --> 00:35:23,360
The returning waters threaten
to drown their colony.

419
00:35:23,400 --> 00:35:26,480
They must waterproof their tunnels

420
00:35:26,520 --> 00:35:28,760
before it arrives.

421
00:35:30,800 --> 00:35:33,120
It's a race against time.

422
00:35:34,080 --> 00:35:36,120
But they have another problem...

423
00:35:37,120 --> 00:35:40,160
..one that comes from within
and threatens

424
00:35:40,200 --> 00:35:42,440
to undo all their hard work.

425
00:35:45,240 --> 00:35:48,920
The termites have entered into
a partnership with a white fungus.

426
00:35:50,320 --> 00:35:52,400
They tend and feed it.

427
00:35:53,680 --> 00:35:55,400
In exchange...

428
00:35:56,440 --> 00:36:00,840
..it provides almost
their sole supply of food.

429
00:36:00,880 --> 00:36:04,720
The termites may be doing everything
to stop water coming in...

430
00:36:07,000 --> 00:36:09,440
..but their fungus
is trying to break out,

431
00:36:09,480 --> 00:36:12,440
growing through the tunnels...

432
00:36:17,320 --> 00:36:19,040
..throwing out mushrooms...

433
00:36:21,520 --> 00:36:24,160
..so it can release its spores.

434
00:36:30,000 --> 00:36:35,200
But mushrooms are irresistible
to baboons.

435
00:36:36,240 --> 00:36:40,200
And to get them,
they break open the mound.

436
00:36:43,400 --> 00:36:45,920
The termites swing into action,

437
00:36:45,960 --> 00:36:49,120
sealing the breach from the inside.

438
00:36:50,800 --> 00:36:53,760
(FRENZIED MUSIC)

439
00:36:57,520 --> 00:36:59,880
It will dry hard as rock...

440
00:37:01,560 --> 00:37:05,160
..keeping out the neighbours
and the coming flood.

441
00:37:06,480 --> 00:37:08,800
(WIND WHISTLES)

442
00:37:08,840 --> 00:37:11,280
Some islands are forged
by the earth...

443
00:37:12,240 --> 00:37:14,720
..others by tiny creatures,

444
00:37:14,760 --> 00:37:16,880
but in the headwaters,

445
00:37:16,920 --> 00:37:20,560
it's giant animals
that change entire landscapes.

446
00:37:26,560 --> 00:37:29,520
The water here is deep and permanent.

447
00:37:30,520 --> 00:37:36,960
It's so wet that some of the islands
literally float.

448
00:37:38,080 --> 00:37:43,160
And abundant plant life provides
year-round food for elephants.

449
00:37:44,400 --> 00:37:46,960
(ELEPHANT SNORTS)

450
00:37:49,480 --> 00:37:54,160
This is why they choose
to stay in the delta.

451
00:37:55,640 --> 00:37:58,800
The good times outweigh the bad.

452
00:38:04,320 --> 00:38:07,600
And these massive animals

453
00:38:07,640 --> 00:38:12,160
are capable of causing huge changes
to the delta.

454
00:38:13,240 --> 00:38:15,240
(UPBEAT PERCUSSIVE MUSIC)

455
00:38:20,480 --> 00:38:23,160
Elephants dislodge vegetation...

456
00:38:25,520 --> 00:38:28,320
..which accumulates into rafts...

457
00:38:33,760 --> 00:38:35,800
..growing as they journey.

458
00:38:44,280 --> 00:38:46,040
They can come together...

459
00:38:47,120 --> 00:38:49,760
..to create floating islands.

460
00:38:52,480 --> 00:38:54,200
Hippos then take over.

461
00:38:55,200 --> 00:38:58,280
They crash through vegetation...

462
00:39:01,520 --> 00:39:03,520
..creating channels...

463
00:39:04,840 --> 00:39:07,160
a spiderweb of waterways...

464
00:39:08,280 --> 00:39:10,080
..others can exploit.

465
00:39:26,080 --> 00:39:29,320
The hippos also keep
the lagoons open...

466
00:39:32,400 --> 00:39:36,960
..which allows more delicate plants,
like waterlilies, to grow.

467
00:39:38,160 --> 00:39:40,320
They may only be small,

468
00:39:40,360 --> 00:39:44,760
but these lily pad islands
have a big influence.

469
00:39:45,960 --> 00:39:47,720
The leaves give shade,

470
00:39:47,760 --> 00:39:52,240
helping to keep the water cool
and give cover to fish.

471
00:39:56,840 --> 00:39:59,720
And their flowers offer rich nectar.

472
00:40:06,000 --> 00:40:10,480
The lily pads are home to a bird
that spends its days island hopping.

473
00:40:13,720 --> 00:40:16,600
The jacana, or lily-trotter.

474
00:40:19,440 --> 00:40:22,320
Exceptionally long toes
spread its weight.

475
00:40:25,000 --> 00:40:28,080
It can almost walk on water.

476
00:40:29,560 --> 00:40:32,680
The jacana has evolved
to spend its entire life...

477
00:40:34,680 --> 00:40:37,400
..on these floating islands.

478
00:40:40,040 --> 00:40:42,000
The lilies provide food...

479
00:40:43,400 --> 00:40:46,000
and a place to raise a family.

480
00:40:46,040 --> 00:40:47,880
(CHICK CHEEPING)

481
00:40:49,400 --> 00:40:51,480
(INSECTS BUZZING)

482
00:40:55,200 --> 00:40:57,360
(CHEEPING)

483
00:41:02,320 --> 00:41:05,840
Chicks are brought up
by their single dad.

484
00:41:13,120 --> 00:41:16,040
He has a clever way
of keeping them safe.

485
00:41:16,080 --> 00:41:17,960
(CHICKS CHEEPING)

486
00:41:20,720 --> 00:41:22,200
(HIPPO SNORTS)

487
00:41:22,240 --> 00:41:25,240
He carries them under his wings...

488
00:41:26,200 --> 00:41:28,880
..until they find their feet.

489
00:41:28,920 --> 00:41:31,000
(HIPPO GRUNTING)

490
00:41:31,040 --> 00:41:33,920
But this family is being watched.

491
00:41:33,960 --> 00:41:35,760
(CHICK CHEEPS)

492
00:41:35,800 --> 00:41:38,200
The hippo is not the problem.

493
00:41:38,240 --> 00:41:39,800
(HIPPO GRUNTS)

494
00:41:39,840 --> 00:41:43,560
A rival jacana
is eyeing the territory.

495
00:41:47,720 --> 00:41:52,080
But Dad's not going to let anyone
muscle in on his lilies.

496
00:41:54,760 --> 00:41:57,000
(SQUAWKING)

497
00:41:57,040 --> 00:41:59,840
(FRENZIED SQUAWKING)

498
00:42:05,960 --> 00:42:08,560
Calm restored...

499
00:42:09,800 --> 00:42:12,080
..for now at least.

500
00:42:20,520 --> 00:42:23,840
Chief's Island has come through
for the hyena clan.

501
00:42:25,720 --> 00:42:30,600
Their scavenging adaptations
saw them through the tough times.

502
00:42:31,920 --> 00:42:33,760
So now...

503
00:42:33,800 --> 00:42:35,160
(HYENAS YAPPING)

504
00:42:35,200 --> 00:42:37,280
..they can enjoy the good times.

505
00:42:41,160 --> 00:42:42,920
(CUBS YIPPING)

506
00:42:42,960 --> 00:42:45,440
And their island queen...

507
00:42:46,880 --> 00:42:49,600
..also has a new arrival.

508
00:42:53,400 --> 00:42:56,480
The latest member
of the Chief's Island clan.

509
00:42:59,040 --> 00:43:01,040
(CUB SQUEAKS SOFTLY)

510
00:43:05,680 --> 00:43:08,960
The delta shapes the lives
of every animal

511
00:43:09,000 --> 00:43:12,000
that lives within
its powerful influence.

512
00:43:14,520 --> 00:43:18,920
They respond to its dynamic ebb
and flow of water.

513
00:43:22,200 --> 00:43:24,600
For some...

514
00:43:24,640 --> 00:43:26,640
this brings challenge.

515
00:43:34,520 --> 00:43:36,280
But for others...

516
00:43:37,200 --> 00:43:40,440
..the delta brings great benefits...

517
00:43:43,400 --> 00:43:46,000
..that enable them to prosper.

518
00:43:49,760 --> 00:43:53,360
As long as the distant rains
continue to fall,

519
00:43:53,400 --> 00:43:56,800
this unique world of island...

520
00:43:57,840 --> 00:44:00,360
..will emerge every year...

521
00:44:01,600 --> 00:44:04,000
..from the desert sands.

522
00:44:04,040 --> 00:44:06,040
(EPIC ORCHESTRAL MUSIC)

523
00:44:06,080 --> 00:44:08,200
AccessibleCustomerService@sky.uk