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A Perfect Planet.
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00:00:43,840 --> 00:00:48,040
We live in a world with
a violent atmosphere.
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00:00:51,320 --> 00:00:53,320
Rain clouds form,
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00:00:53,320 --> 00:00:57,640
and powerful winds carry their
fresh water around the globe.
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00:01:00,040 --> 00:01:05,480
Without this, our perfect planet
simply couldn't function...
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00:01:05,480 --> 00:01:10,360
...for all life on land
depends on the weather.
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00:01:23,040 --> 00:01:26,560
We all know that the weather
can change on a daily,
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00:01:26,560 --> 00:01:28,600
even hourly, basis.
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00:01:30,840 --> 00:01:35,080
But annual weather patterns
have been stable for millennia...
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00:01:36,360 --> 00:01:41,120
...and it's this reliability
on which life depends.
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00:01:41,120 --> 00:01:42,920
ANIMALS AND BIRDS CALL
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00:01:46,880 --> 00:01:51,680
Every year in October, the weather
brings a dramatic transformation
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00:01:51,680 --> 00:01:55,080
to this tiny patch
of forest in Zambia.
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00:02:00,000 --> 00:02:02,640
Storm clouds begin to build.
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00:02:06,240 --> 00:02:08,200
THUNDER CRASHES
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00:02:10,920 --> 00:02:17,000
And right on cue, straw-coloured
fruit bats start to appear.
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00:02:22,800 --> 00:02:27,520
They've travelled hundreds, if not
thousands, of miles to be here.
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00:02:35,160 --> 00:02:39,080
And they always arrive
at exactly the same time.
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00:02:41,760 --> 00:02:45,880
They know that these rains
will transform this forest,
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allowing countless
fruit trees to ripen.
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And the bats gorge on
the new-found abundance.
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00:03:16,880 --> 00:03:20,080
For just 12 weeks every year,
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00:03:20,080 --> 00:03:25,280
this forest becomes home
to ten million fruit bats.
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One of the greatest gatherings
of mammals on Earth,
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all crowding into an area no bigger
than a dozen football pitches.
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00:03:41,480 --> 00:03:44,480
From this hub, the bats fan out,
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consuming more than
300,000 tonnes of fruit,
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spreading the seeds and
regenerating the forests.
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00:04:11,480 --> 00:04:17,520
Africa's largest wildlife migration
entirely dependent on the rain
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00:04:17,520 --> 00:04:21,240
that comes to this
small corner of Zambia
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at the same time each year.
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Every second,
over 13 million tonnes of water
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00:04:44,120 --> 00:04:48,800
evaporate from our oceans,
forming clouds.
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00:04:55,280 --> 00:04:58,240
The spin of the Earth
and the prevailing winds
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00:04:58,240 --> 00:05:01,120
determine where these clouds blow.
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00:05:02,880 --> 00:05:06,440
As a consequence,
some places get less rain...
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...and others much more.
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00:05:12,680 --> 00:05:14,800
The Amazon rainforest...
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00:05:16,160 --> 00:05:17,680
THUNDER CRASHES
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00:05:17,680 --> 00:05:20,880
...one of the wettest
places on Earth.
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00:05:30,880 --> 00:05:33,360
It gets three metres
of rain a year...
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...so life has learned to deal
with the near-daily downpours.
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Every year, for thousands of years,
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the persistent rains have flooded
vast tracts of the Amazon...
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...turning the jungle
into a seasonal wetland.
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00:06:02,320 --> 00:06:07,520
Anything living here
must either climb or swim.
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00:06:11,840 --> 00:06:16,200
But there's one extraordinary
animal that has turned this deluge
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from a disaster into an opportunity.
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This fire ant has reached
the edge of her known world.
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00:06:34,080 --> 00:06:38,800
Her way forward has now become
blocked by the rising waters.
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She's one of many,
and in a few minutes
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their underground home
will be submerged.
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Forced to evacuate,
workers and soldiers try
to save the larval young.
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00:07:06,080 --> 00:07:10,840
As their nest floods,
the colony seems to be doomed.
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But from chaos comes order.
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00:07:24,280 --> 00:07:29,000
The fire ants band together, each
locking legs with its neighbours.
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They're building a living raft.
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00:07:37,240 --> 00:07:42,800
Each ant is covered in fine hairs
that trap air against its body.
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00:07:47,040 --> 00:07:53,040
As the raft forms, this air creates
a cushion for them all to float on.
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This is the power of the colony.
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00:07:59,720 --> 00:08:03,120
By working together,
they've become unsinkable.
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00:08:07,600 --> 00:08:09,880
And no-one gets left behind.
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00:08:22,840 --> 00:08:27,720
Pulled from the shallows, the colony
is now at the mercy of the flood.
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00:08:33,520 --> 00:08:35,680
Holding tight to the larvae
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and keeping their queen hidden
at the centre of the raft,
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00:08:38,920 --> 00:08:42,560
the colony drifts
into deeper water...
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00:08:47,880 --> 00:08:50,320
...where they're vulnerable to fish
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that now swim through
the flooded forest.
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00:08:59,640 --> 00:09:04,800
Those that lose their grip must
get back to the safety of the raft.
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00:09:16,280 --> 00:09:20,280
With jaws that join to
become a surgical needle,
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00:09:20,280 --> 00:09:24,040
this pond skater
could suck an ant dry.
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00:09:35,480 --> 00:09:38,560
But together the colony is strong,
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00:09:38,560 --> 00:09:41,320
and it's time to repel boarders.
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00:09:52,800 --> 00:09:56,200
The ants can travel
like this for weeks.
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00:09:59,080 --> 00:10:02,520
They've even come to depend
on the flood to carry them
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00:10:02,520 --> 00:10:04,920
to new feeding grounds.
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00:10:17,800 --> 00:10:22,120
At last, the ants can
make their raft secure.
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Surging forward, they
claim their new home...
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...evicting current tenants
without hesitation.
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00:10:39,240 --> 00:10:42,760
One of the first to safety
is their larval queen,
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carried from the heart of the raft.
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This palm will be their home
for the next three months,
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00:10:56,200 --> 00:11:00,760
until the floodwaters recede
and they can head back underground.
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00:11:14,000 --> 00:11:17,480
The average temperature
of our planet hasn't varied
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by more than a single degree
Celsius in 10,000 years.
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00:11:24,000 --> 00:11:26,720
This has made our climate stable,
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allowing animals to
fine-tune their behaviour
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around predictable weather patterns.
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00:11:36,240 --> 00:11:38,520
October in the Amazon.
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00:11:40,240 --> 00:11:42,800
The heaviest rains
have come to an end,
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00:11:42,800 --> 00:11:47,200
and the falling river level
exposes a new landscape.
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00:11:50,000 --> 00:11:55,200
Three weeks ago, these mile-wide
sand bars didn't exist.
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00:11:57,480 --> 00:12:01,760
In another three months,
they'll be back under water.
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00:12:04,240 --> 00:12:10,480
But now they provide a crucial
opportunity for giant river turtles.
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00:12:13,160 --> 00:12:18,000
They've been coming here
at precisely this time
of year for generations.
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00:12:23,760 --> 00:12:28,080
50,000 of them - a quarter
of the world's population.
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00:12:32,280 --> 00:12:34,440
They're all here for one reason.
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00:12:36,000 --> 00:12:38,920
But their window of
opportunity is short,
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00:12:38,920 --> 00:12:41,560
so timing is everything.
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00:12:46,160 --> 00:12:50,440
Scaling the three-metre-high
banks will take this female
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00:12:50,440 --> 00:12:54,480
higher and drier than
she's been for months.
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She's come here to lay her eggs.
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00:13:01,760 --> 00:13:04,080
But others have beaten her to it.
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00:13:14,400 --> 00:13:17,560
The early arrivals
have already claimed
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00:13:17,560 --> 00:13:20,080
nearly every inch of the beach...
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00:13:21,240 --> 00:13:23,880
...and there are still
many more turtles to come.
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00:13:30,280 --> 00:13:33,440
Wherever she turns,
the space is taken.
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SAND PATTERS
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But being fashionably late
does have an advantage.
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Had she arrived earlier,
her eggs might have been
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dug up by those searching
for somewhere to lay.
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She's found her spot.
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Settling down, she lays
nearly 100 eggs.
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00:14:20,520 --> 00:14:23,880
Burying them keeps them
safe from predators,
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and the warm sand
incubates the clutch.
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00:14:34,400 --> 00:14:39,960
They must hatch before the river
rises again and floods the sandbar.
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Any turtles that lay after her
may have left it too late.
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00:14:55,320 --> 00:14:58,600
Hopefully, she has
got her timing right.
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00:15:11,920 --> 00:15:17,200
Two months on, and the hatchlings
emerge into the world.
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00:15:27,080 --> 00:15:30,640
They were laid at the perfect time.
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00:15:30,640 --> 00:15:32,880
Hundreds scramble for the river
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just as the water starts to rise.
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Those still to hatch
aren't so lucky.
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This year, the heavy rains
have returned early.
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THUNDER RUMBLES
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The nesting beach is
beginning to flood.
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00:16:22,560 --> 00:16:26,000
Most hatchlings can escape in time.
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00:16:33,560 --> 00:16:35,920
Those still below ground...
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00:16:37,240 --> 00:16:39,360
...will drown in their nests.
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00:16:44,320 --> 00:16:49,200
For thousands of years, giant river
turtles have timed their breeding
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around the Amazon's
reliable cycles of rain.
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00:16:56,880 --> 00:17:00,360
But today, our weather is changing.
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00:17:04,760 --> 00:17:11,480
Disastrous early floods like this
used to happen once every 20 years.
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00:17:11,480 --> 00:17:16,320
Now the turtles have to
deal with them every four.
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00:17:30,720 --> 00:17:34,920
Winds may carry huge amounts
of rain to the Amazon,
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00:17:34,920 --> 00:17:39,840
but they don't provide this service
to every corner of the planet.
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00:17:41,560 --> 00:17:48,200
A third of the land receives
less than 25cm of rain a year.
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00:17:52,320 --> 00:17:58,000
Deserts are scarred by desiccating
winds and baked by the sun.
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00:18:00,720 --> 00:18:06,160
But even weather as challenging as
this can be perfect for the locals.
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As darkness falls in the
coastal deserts of South Africa,
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the dunes come alive...
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00:18:18,000 --> 00:18:19,880
HIGH-PITCHED CALL
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00:18:19,880 --> 00:18:23,760
...with the call of a
surprising desert dweller.
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HIGH-PITCHED CALL
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CALL CONTINUES
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A rain frog.
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00:18:46,880 --> 00:18:53,760
Not what you'd expect in a place
that gets just 7cm of rain a year.
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00:18:58,200 --> 00:19:02,240
To survive here, she has
to avoid the heat of the day
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00:19:02,240 --> 00:19:04,280
buried in the sand.
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00:19:06,520 --> 00:19:09,560
But each night, she heads out...
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00:19:09,560 --> 00:19:12,280
..on her hunt for moisture.
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00:19:15,800 --> 00:19:20,240
Short, stumpy legs and a plump body
are ideal for digging...
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...but not so good
for getting around.
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00:19:30,560 --> 00:19:36,480
She can't hop, so she
waddles across the dunes.
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00:19:43,600 --> 00:19:47,880
The world's slowest steeplechaser.
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Obstacles are tackled
with dogged perseverance.
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00:20:03,160 --> 00:20:07,520
She can travel a whopping
38 metres a night.
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00:20:07,520 --> 00:20:13,200
No mean feat when you're the same
size and shape as a marshmallow.
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00:20:18,800 --> 00:20:20,840
Termites.
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00:20:20,840 --> 00:20:24,720
They are 75% water -
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a meal and a drink in one.
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00:20:32,320 --> 00:20:36,560
But she's not the
most agile predator.
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00:20:38,120 --> 00:20:42,320
Maybe if they just
came a little closer...?
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Oh, dear.
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00:20:50,400 --> 00:20:53,480
Perhaps if they stop moving...?
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00:21:14,080 --> 00:21:15,760
At last.
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00:21:17,000 --> 00:21:20,640
But now she has another challenge.
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00:21:20,640 --> 00:21:24,720
To swallow her food, she
must squash in her eyeballs
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00:21:24,720 --> 00:21:27,240
to push it down her throat.
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00:21:35,880 --> 00:21:38,040
Termites may be juicy,
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but they don't provide her with
quite enough water to survive.
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00:21:45,520 --> 00:21:48,080
It rarely rains here,
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00:21:48,080 --> 00:21:53,640
but coastal deserts do get another
reliable source of moisture.
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00:22:04,400 --> 00:22:09,080
At night - cool, moist air
is blown in from the ocean,
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00:22:09,080 --> 00:22:13,440
forming fog banks that
shroud the desert in mist.
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It condenses on vegetation,
wetting the sand beneath.
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00:22:29,800 --> 00:22:35,200
So it's here that she waits,
absorbing moisture through her skin.
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00:22:43,120 --> 00:22:47,800
Rain frogs are so dependent on this
water that they can only survive
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00:22:47,800 --> 00:22:52,720
in places with at least
100 days of fog a year.
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00:22:54,920 --> 00:22:57,120
And on the foggiest nights,
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00:22:57,120 --> 00:23:00,120
when other frogs have
emerged onto the dunes,
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00:23:00,120 --> 00:23:04,360
she takes her opportunity
to find love.
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00:23:11,760 --> 00:23:15,680
Male rain frogs are
smaller than the females,
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00:23:15,680 --> 00:23:20,920
and his stubby legs
make it hard to hold on...
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00:23:20,920 --> 00:23:24,920
..so he glues himself onto her back.
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00:23:35,480 --> 00:23:37,840
Still locked in their embrace,
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00:23:37,840 --> 00:23:42,400
the pair head back beneath the sand,
where they'll lay their eggs,
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00:23:42,400 --> 00:23:45,720
safe from the heat
of the desert sun.
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00:23:54,240 --> 00:23:57,840
But there's one desert
that gets so cold
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00:23:57,840 --> 00:24:01,800
that liquid water
simply can't exist.
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00:24:04,480 --> 00:24:08,600
Winter in Mongolia's Gobi Desert.
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40 degrees below freezing.
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00:24:15,640 --> 00:24:20,280
One of the driest and most extreme
environments in the world.
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00:24:26,960 --> 00:24:30,680
Most animals can't survive
weather like this...
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00:24:33,080 --> 00:24:35,680
...but there's one unique mammal
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00:24:35,680 --> 00:24:38,880
that manages to eke
out a living here.
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00:24:41,520 --> 00:24:48,240
The Gobi is home to the last 1,000
wild Bactrian camels on Earth...
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00:24:50,280 --> 00:24:53,120
...surviving at the very
edge of what's possible.
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00:24:54,400 --> 00:24:56,600
CAMEL GRUNTS
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00:24:56,600 --> 00:24:59,000
Even camels need moisture,
201
00:24:59,000 --> 00:25:02,960
but any water here
is now frozen solid.
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00:25:06,480 --> 00:25:09,680
It's down to the bull
to find a solution.
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00:25:12,480 --> 00:25:14,320
BULL GRUNTS
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00:25:17,120 --> 00:25:19,120
Setting off with his herd,
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00:25:19,120 --> 00:25:22,560
his search could cover
thousands of square miles.
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00:25:28,440 --> 00:25:33,280
Driving them forward, he can
keep going for days on end.
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00:25:43,760 --> 00:25:47,120
Herds come together from
across their vast range...
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00:25:48,720 --> 00:25:50,920
...all looking for the same thing.
209
00:25:59,560 --> 00:26:05,880
These long-distance specialists can
smell moisture from 30 miles away...
210
00:26:05,880 --> 00:26:08,200
...and they've picked up a scent.
211
00:26:13,160 --> 00:26:17,560
Even in the Gobi, one of
the driest places on Earth,
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00:26:17,560 --> 00:26:21,560
wind can provide a rare
source of moisture.
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00:26:23,560 --> 00:26:27,920
Snow is blown to this
desert from Siberia.
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00:26:29,640 --> 00:26:33,000
Where it settles is
impossible to predict,
215
00:26:33,000 --> 00:26:35,120
and it may not last long.
216
00:26:42,080 --> 00:26:47,320
But for now, at least, this bull has
found what he's been searching for.
217
00:26:57,320 --> 00:26:59,440
In the cold, dry air,
218
00:26:59,440 --> 00:27:01,520
snow doesn't melt...
219
00:27:03,400 --> 00:27:05,920
...so it must be eaten.
220
00:27:15,120 --> 00:27:19,040
The Gobi's windblown
snow is a lifeline
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00:27:19,040 --> 00:27:22,440
that will sustain his herd
throughout the winter.
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00:27:30,160 --> 00:27:33,440
Even in this most hostile of places,
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00:27:33,440 --> 00:27:37,840
weather still provides
just enough for survival.
224
00:27:49,600 --> 00:27:53,800
The largest, most unpredictable
weather on the planet
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00:27:53,800 --> 00:27:56,880
starts far out at sea.
226
00:28:02,560 --> 00:28:06,560
Hurricanes, typhoons
and tropical cyclones
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00:28:06,560 --> 00:28:10,120
are violent, short-lived megastorms.
228
00:28:11,600 --> 00:28:14,560
But there's a far more
reliable weather system
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00:28:14,560 --> 00:28:16,920
that originates over the ocean...
230
00:28:18,120 --> 00:28:22,720
...one that is eagerly
anticipated by all in its path.
231
00:28:25,640 --> 00:28:31,920
Monsoons are seasonal winds that
blow at the same time each year...
232
00:28:34,320 --> 00:28:39,160
...and they carry colossal amounts
of water from the ocean to the land.
233
00:28:46,640 --> 00:28:48,240
Christmas Island.
234
00:28:49,560 --> 00:28:53,160
A remote speck of rock
in the Indian Ocean.
235
00:28:57,480 --> 00:29:03,960
For the last four months, its forest
interior has remained dry and dusty.
236
00:29:07,240 --> 00:29:11,120
Life here is waiting for change.
237
00:29:14,000 --> 00:29:18,960
In November, the first storms
of the monsoon reach the island.
238
00:29:18,960 --> 00:29:21,440
THUNDER CRASHES
239
00:29:36,520 --> 00:29:40,960
They're a welcome relief for those
that have suffered through the dry.
240
00:29:45,280 --> 00:29:50,440
And they are vital for the island's
most numerous residents.
241
00:30:04,480 --> 00:30:07,920
The red crabs of Christmas Island.
242
00:30:12,040 --> 00:30:15,280
They've spent the dry season
sheltering in damp burrows
243
00:30:15,280 --> 00:30:17,280
beneath the leaf litter.
244
00:30:20,520 --> 00:30:24,880
Crabs breathe through gills
that must be kept moist.
245
00:30:29,240 --> 00:30:33,040
So it's only with the return
of the annual monsoon
246
00:30:33,040 --> 00:30:37,040
that these land crabs
can finally emerge.
247
00:30:44,240 --> 00:30:46,360
With the humidity now high enough,
248
00:30:46,360 --> 00:30:50,080
they can begin an
epic trek to the coast.
249
00:31:02,680 --> 00:31:07,280
Every red crab comes together
from across the island,
250
00:31:07,280 --> 00:31:10,000
and they do so in their millions.
251
00:31:12,320 --> 00:31:15,240
50 million, to be precise.
252
00:31:29,560 --> 00:31:34,920
They've come to release their eggs
that can only develop in the ocean.
253
00:31:36,360 --> 00:31:38,800
There's just one small problem.
254
00:31:40,000 --> 00:31:42,920
They may be crabs...
255
00:31:42,920 --> 00:31:45,120
...but they can't swim.
256
00:31:48,720 --> 00:31:51,080
They're scared of the sea.
257
00:32:04,920 --> 00:32:07,240
But they don't have a choice.
258
00:32:08,560 --> 00:32:13,080
They must release their eggs
on the highest tide.
259
00:32:19,080 --> 00:32:23,080
Each carries around 100,000 eggs,
260
00:32:23,080 --> 00:32:25,720
so over just two or three nights,
261
00:32:25,720 --> 00:32:28,920
trillions are released
into the ocean.
262
00:32:31,120 --> 00:32:34,880
Though some are more
successful than others.
263
00:33:00,000 --> 00:33:04,640
Once their work is done,
the crabs will return to the forest.
264
00:33:21,640 --> 00:33:24,360
Then, four weeks later,
265
00:33:24,360 --> 00:33:26,760
on the next highest tide...
266
00:33:32,040 --> 00:33:34,280
...having hatched out to sea,
267
00:33:34,280 --> 00:33:39,400
a new generation of red crabs
returns to the same beach.
268
00:33:41,680 --> 00:33:43,520
In good years like this one,
269
00:33:43,520 --> 00:33:47,440
countless millions arrive back on
the shores of Christmas Island,
270
00:33:47,440 --> 00:33:50,040
turning the beaches red.
271
00:34:06,960 --> 00:34:11,800
Like their parents, they also need
moisture in the air to breathe.
272
00:34:14,320 --> 00:34:16,680
So before the rains move on,
273
00:34:16,680 --> 00:34:22,320
the young crabs must undertake their
own epic journey into the forest,
274
00:34:22,320 --> 00:34:26,120
where they'll wait out
the next few months of dry.
275
00:34:46,280 --> 00:34:48,520
The Christmas Island crab -
276
00:34:48,520 --> 00:34:52,920
entirely reliant on the
return of the monsoon.
277
00:35:03,680 --> 00:35:09,840
The annual rhythms of the weather
shape life across our planet.
278
00:35:12,240 --> 00:35:14,400
In some parts of the world,
279
00:35:14,400 --> 00:35:18,840
seasonal cycles of wet and dry
can bring dramatic change.
280
00:35:21,320 --> 00:35:24,240
And there are few places
where this is more apparent
281
00:35:24,240 --> 00:35:26,520
than southern Africa.
282
00:35:33,560 --> 00:35:35,920
The Zambezi River.
283
00:35:37,400 --> 00:35:43,880
It flows across six countries and
drains half a million square miles.
284
00:35:57,920 --> 00:36:00,440
At the peak of the wet season,
285
00:36:00,440 --> 00:36:07,080
5,000 tonnes of water cascade
over Victoria Falls every second.
286
00:36:09,560 --> 00:36:13,000
And yet, each year
when the rains stop,
287
00:36:13,000 --> 00:36:16,280
these falls run dry.
288
00:36:23,920 --> 00:36:28,000
It's almost as if someone
turns off the tap.
289
00:36:33,080 --> 00:36:34,560
May...
290
00:36:37,960 --> 00:36:39,560
..December.
291
00:36:42,760 --> 00:36:44,480
Wet season...
292
00:36:48,000 --> 00:36:49,800
..dry season.
293
00:36:52,600 --> 00:36:56,520
It's happened like this
for thousands of years.
294
00:37:02,520 --> 00:37:07,600
But there are signs that
the weather here is changing.
295
00:37:07,600 --> 00:37:12,440
In recent years, the volume of
water flowing over Victoria Falls
296
00:37:12,440 --> 00:37:14,960
has dropped by half.
297
00:37:19,120 --> 00:37:22,520
A concern for animals
that have come to rely on
298
00:37:22,520 --> 00:37:26,200
the natural rhythms of wet and dry.
299
00:37:39,160 --> 00:37:45,040
Zambia's Luangwa River is a
major tributary of the Zambezi.
300
00:37:46,800 --> 00:37:50,000
Every year, as the
dry season takes hold,
301
00:37:50,000 --> 00:37:53,120
it dwindles into pools.
302
00:37:56,480 --> 00:38:00,080
Accommodation starts to
get tight for the locals.
303
00:38:00,080 --> 00:38:01,960
HIPPO SNORTS
304
00:38:03,920 --> 00:38:09,040
With no other water around, the
river becomes a magnet for visitors.
305
00:38:14,880 --> 00:38:19,600
Millions of red-billed quelea
flock to the water's edge.
306
00:38:23,800 --> 00:38:27,640
These seed eaters need
to drink every day...
307
00:38:46,680 --> 00:38:49,360
...and Nile crocodiles know it.
308
00:38:50,800 --> 00:38:53,200
They may not have
eaten for six months.
309
00:38:54,360 --> 00:38:59,320
For them, the dry season is
the start of the good times.
310
00:39:08,840 --> 00:39:13,720
And they are not the only ones
to depend on this time of year.
311
00:39:18,880 --> 00:39:22,680
Carmine bee-eaters have
flown hundreds of miles
312
00:39:22,680 --> 00:39:24,960
from the rainforests of the Congo...
313
00:39:26,600 --> 00:39:29,880
...arriving at the
peak of the dry season,
314
00:39:29,880 --> 00:39:34,800
when steep sandbanks are
exposed by the falling water.
315
00:39:41,200 --> 00:39:43,840
They're a perfect place to nest,
316
00:39:43,840 --> 00:39:46,760
out of reach of
predators from above.
317
00:39:56,080 --> 00:40:01,600
Bee-eater burrows can extend for
two metres into the soft river sand.
318
00:40:03,080 --> 00:40:05,880
Already home to 6,000 nests,
319
00:40:05,880 --> 00:40:10,600
real estate at Bee-eater Towers
is in high demand.
320
00:40:14,520 --> 00:40:18,440
But it pays not to build
too close to the neighbours.
321
00:40:28,920 --> 00:40:34,000
As more birds arrive, competition
for the best nesting sites heats up.
322
00:40:44,960 --> 00:40:47,000
It's thirsty work.
323
00:40:57,760 --> 00:41:01,640
In the sudden commotion,
they're vulnerable from below...
324
00:41:03,720 --> 00:41:05,280
...and above.
325
00:41:09,240 --> 00:41:11,880
African fish eagles.
326
00:41:20,240 --> 00:41:23,200
They are permanent residents here.
327
00:41:23,200 --> 00:41:27,160
But at this time of the year,
they don't just eat fish.
328
00:41:32,080 --> 00:41:35,680
The safest place to be
is inside a burrow.
329
00:41:37,360 --> 00:41:43,040
But an eagle fly-by sends shock
waves of panic through the colony.
330
00:41:55,920 --> 00:42:00,880
The eagles' strategy is to pin
their prey against the river bank.
331
00:42:04,840 --> 00:42:07,600
With the colony in disarray,
332
00:42:07,600 --> 00:42:10,040
the predators have the advantage.
333
00:42:50,160 --> 00:42:54,560
These fish eagles also choose
to breed in the dry season,
334
00:42:54,560 --> 00:42:58,800
because they need the bee-eaters
as food for their chicks.
335
00:43:06,040 --> 00:43:11,080
But this year's dry season
shows no sign of letting up.
336
00:43:18,680 --> 00:43:22,040
Parts of the river are now bone-dry,
337
00:43:22,040 --> 00:43:25,840
forcing huge male hippos
from their home.
338
00:43:36,280 --> 00:43:38,400
With nowhere left to turn,
339
00:43:38,400 --> 00:43:41,920
they must converge on the few
remaining patches of water...
340
00:43:41,920 --> 00:43:43,840
HIPPO GRUNTS
341
00:43:43,840 --> 00:43:46,560
..but these are already occupied.
342
00:43:59,400 --> 00:44:03,080
The resident bull here can't
tolerate another big male
343
00:44:03,080 --> 00:44:05,600
in his shrinking pool.
344
00:44:08,040 --> 00:44:09,960
HIPPO BELLOWS
345
00:44:36,040 --> 00:44:38,960
The newcomer is banished.
346
00:44:50,000 --> 00:44:53,080
Still the sun bakes the land...
347
00:44:56,200 --> 00:44:59,320
...with devastating consequences.
348
00:45:31,240 --> 00:45:34,320
Hundreds of nests are wiped out.
349
00:45:42,520 --> 00:45:46,640
Southern Africa has
experienced dry seasons
350
00:45:46,640 --> 00:45:48,840
for thousands of years.
351
00:45:50,440 --> 00:45:53,400
But this is something different.
352
00:45:58,360 --> 00:46:04,000
Record high temperatures and the
lowest rainfall in nearly 40 years
353
00:46:04,000 --> 00:46:09,240
have thrown parts of Africa into one
of the worst droughts in a century.
354
00:46:16,560 --> 00:46:18,400
THUNDER CRASHES
355
00:46:24,920 --> 00:46:30,400
Across the planet, our once
stable climate is changing.
356
00:46:35,240 --> 00:46:37,440
Weather is less reliable...
357
00:46:39,840 --> 00:46:43,080
...and is getting more extreme.
358
00:46:46,760 --> 00:46:49,640
Wildfires are becoming
more frequent.
359
00:47:05,360 --> 00:47:08,040
Droughts are more intense.
360
00:47:18,960 --> 00:47:23,040
And storms are more ferocious.
361
00:47:27,200 --> 00:47:32,440
All this from a recent rise
in global temperatures
362
00:47:32,440 --> 00:47:35,360
of just a single degree Celsius.
363
00:47:37,040 --> 00:47:40,400
Yet if climate change
continues unchecked,
364
00:47:40,400 --> 00:47:46,560
we may see a rise of almost five
degrees by the end of the century.
365
00:47:48,400 --> 00:47:53,000
We can only imagine what
this will do to our weather.
366
00:48:11,680 --> 00:48:15,120
There are a few things more daunting
for the wildlife film crew
367
00:48:15,120 --> 00:48:20,120
than the prospect of finding
a very rare animal in a vast area.
368
00:48:24,120 --> 00:48:28,120
But that is the mission
in Mongolia's Gobi Desert -
369
00:48:28,120 --> 00:48:31,640
to film an animal
numbering less than 500
370
00:48:31,640 --> 00:48:35,480
in a wilderness of
half a million square miles.
371
00:48:41,280 --> 00:48:44,480
We're all loaded up. We got 40 cases
of gear, we got nine vehicles.
372
00:48:44,480 --> 00:48:46,880
We're off,
we're heading to the Gobi.
373
00:48:50,240 --> 00:48:52,720
DAVID ATTENBOROUGH:
From the capital, Ulaanbaatar,
374
00:48:52,720 --> 00:48:55,720
it'll take the team
five days to cross Mongolia
375
00:48:55,720 --> 00:48:58,120
in the depths of winter -
376
00:48:58,120 --> 00:49:02,040
travelling in a convoy
of large camping trucks,
377
00:49:02,040 --> 00:49:04,160
home for the next five weeks.
378
00:49:22,000 --> 00:49:27,920
1,000 miles later, the convoy
reaches the Gobi and makes camp.
379
00:49:32,040 --> 00:49:35,120
Well, we have woken up
on our first morning,
380
00:49:35,120 --> 00:49:38,080
and it's about an hour-and-a-half
before sunrise,
381
00:49:38,080 --> 00:49:42,800
and rather foolishly we let the
fire go out last night, so it's...
382
00:49:42,800 --> 00:49:44,920
..a cool minus 20 in here.
383
00:49:44,920 --> 00:49:48,560
Everything's frozen solid -
toothpaste, hot sauce for breakfast,
384
00:49:48,560 --> 00:49:50,680
even the AP's pee bottle...
385
00:49:50,680 --> 00:49:52,480
..so that's nice.
386
00:49:55,000 --> 00:49:58,600
Finding a scarce animal in
an area the size of Belgium
387
00:49:58,600 --> 00:50:01,480
is clearly no small task...
388
00:50:01,480 --> 00:50:04,400
GARBLED RADIO CONVERSATION
389
00:50:04,400 --> 00:50:08,400
...but impossible without
the help of local researchers.
390
00:50:10,120 --> 00:50:14,480
Each day, the team scour
thousands of square miles.
391
00:50:14,480 --> 00:50:17,000
It's a huge area,
and there's only 450 camels,
392
00:50:17,000 --> 00:50:20,360
so it really is a bit like
a needle in a haystack.
393
00:50:21,600 --> 00:50:24,840
A truly enormous haystack.
394
00:50:29,040 --> 00:50:31,120
450 camels...
395
00:50:29,040 --> 00:50:31,120
ADIYA LAUGHS
396
00:50:31,120 --> 00:50:32,720
...28,000 square miles.
397
00:50:32,720 --> 00:50:34,720
Easy, yeah? Yeah.
398
00:50:34,720 --> 00:50:37,720
And when scanning the
horizon for camels,
399
00:50:37,720 --> 00:50:39,760
mistakes are all too easy.
400
00:50:39,760 --> 00:50:41,240
Another bush.
401
00:50:42,320 --> 00:50:44,600
A bush. Sorry.
402
00:50:46,040 --> 00:50:48,960
Sometimes there's not
even a bush to look at.
403
00:50:48,960 --> 00:50:50,520
See anything? Nothing.
404
00:50:51,800 --> 00:50:53,800
Another hill climbed.
405
00:50:53,800 --> 00:50:55,640
Another trail followed.
406
00:50:55,640 --> 00:50:57,840
Another dead end.
407
00:50:57,840 --> 00:51:00,680
Thankfully, the experts
remain positive.
408
00:51:00,680 --> 00:51:02,520
I hope you can see them soon.
409
00:51:02,520 --> 00:51:04,160
Yeah, yeah. Please.
410
00:51:06,960 --> 00:51:08,840
Two weeks since leaving the UK.
411
00:51:08,840 --> 00:51:11,280
I'm just hoping that we haven't...
412
00:51:11,280 --> 00:51:13,160
...been slightly
overambitious on this one.
413
00:51:13,160 --> 00:51:16,200
Getting slightly worried it
might actually be impossible.
414
00:51:18,000 --> 00:51:19,680
ED SIGHS
415
00:51:21,560 --> 00:51:23,400
Hmm... Good support there, thanks.
416
00:51:24,760 --> 00:51:28,720
Eventually, the team
spot their first camel...
417
00:51:28,720 --> 00:51:31,640
..but, unfortunately,
it spotted them first.
418
00:51:33,040 --> 00:51:35,040
Very far away.
419
00:51:35,040 --> 00:51:38,320
Poaching has made the
surviving camels very nervous,
420
00:51:38,320 --> 00:51:42,280
and once they start running
they can keep going for miles.
421
00:51:44,520 --> 00:51:46,760
WIND HOWLS
422
00:51:46,760 --> 00:51:49,200
And when the winter winds kick off,
423
00:51:49,200 --> 00:51:52,080
all signs of camel vanish.
424
00:51:52,080 --> 00:51:54,640
So, for about the past 24 hours,
we've been experiencing
425
00:51:54,640 --> 00:51:57,520
the Gobi winds. It's been gusting
up to 70mph hour all night,
426
00:51:57,520 --> 00:51:59,840
and the temps have probably
been down to almost -50
427
00:51:59,840 --> 00:52:03,040
with the wind-chill. We just have to
hunker down, we can't film in this.
428
00:52:07,160 --> 00:52:11,440
When the gale eases,
the search reveals new hope.
429
00:52:12,760 --> 00:52:14,840
We got a load of fresh
camel tracks here.
430
00:52:16,320 --> 00:52:19,560
And all tracks head one way -
431
00:52:19,560 --> 00:52:24,120
towards the even more remote
mountainous southern Gobi.
432
00:52:28,160 --> 00:52:31,840
The team must decide
if they should follow.
433
00:52:31,840 --> 00:52:35,600
Do you think that landscape
is likely to be better for us?
434
00:52:35,600 --> 00:52:38,560
More camels and
closer encounters or...?
435
00:52:38,560 --> 00:52:40,560
What's your gut telling you?
436
00:52:42,760 --> 00:52:44,960
Because of the wintertime,
437
00:52:44,960 --> 00:52:47,600
we need to see some snow... Mm.
438
00:52:47,600 --> 00:52:48,760
...to see camels.
439
00:52:50,200 --> 00:52:54,760
To survive in this waterless desert,
the camels depend on finding snow.
440
00:52:56,520 --> 00:52:58,720
So, with none in sight,
441
00:52:58,720 --> 00:53:03,160
the team decide to try their luck
in the icy mountains to the south.
442
00:53:07,640 --> 00:53:09,520
Sure enough, there's snow -
443
00:53:09,520 --> 00:53:11,240
and lots of it.
444
00:53:14,600 --> 00:53:18,840
But the larger camping trucks
struggle in the mountainous terrain,
445
00:53:18,840 --> 00:53:22,000
and the team are forced
to go on without them,
446
00:53:22,000 --> 00:53:27,120
leaving them somewhat more
exposed to the winter conditions.
447
00:53:27,120 --> 00:53:29,440
It's been down to
-25 over the last week.
448
00:53:29,440 --> 00:53:32,920
So very thin canvas tents
will be a whole new experience
449
00:53:32,920 --> 00:53:35,480
in the Gobi Desert for us.
450
00:53:35,480 --> 00:53:39,000
I'm wearing, currently,
two pairs of trousers, thermals,
451
00:53:39,000 --> 00:53:42,880
thermals on top, two pairs of
jumpers, three coats, two hats...
452
00:53:42,880 --> 00:53:45,480
So I THINK I should be all right.
453
00:53:45,480 --> 00:53:46,600
HE EXHALES
454
00:53:48,920 --> 00:53:50,480
TOBY: You all right, Eddie?
455
00:53:50,480 --> 00:53:52,200
Oh, I'm terrific, yeah.
456
00:53:52,200 --> 00:53:54,560
HE LAUGHS
457
00:53:52,200 --> 00:53:54,560
Really terrific!
458
00:53:54,560 --> 00:53:57,200
HE SIGHS CONTENTEDLY
459
00:53:54,560 --> 00:53:57,200
I'm all cosy.
460
00:53:58,640 --> 00:54:00,120
I'm not. I'm cold.
461
00:54:00,120 --> 00:54:01,560
Really cold!
462
00:54:05,800 --> 00:54:11,240
As Adiya predicted,
with snow come camels.
463
00:54:11,240 --> 00:54:14,080
The signs are everywhere.
464
00:54:17,360 --> 00:54:19,080
But having travelled so far,
465
00:54:19,080 --> 00:54:22,200
they can't risk anything
ruining this chance.
466
00:54:22,200 --> 00:54:25,760
HUSHED: Camels don't seem
to like the cars so...
467
00:54:25,760 --> 00:54:27,240
...now we walk.
468
00:54:29,320 --> 00:54:31,640
We've been walking for
about five miles now,
469
00:54:31,640 --> 00:54:33,960
and hiking across this landscape,
470
00:54:33,960 --> 00:54:37,600
it really does give you a new-found
respect for the camels.
471
00:54:43,120 --> 00:54:46,320
We've seen some camels
way out on the plain here,
472
00:54:46,320 --> 00:54:50,800
but in order not to scare them,
John's going to head out on his own.
473
00:55:03,520 --> 00:55:06,520
Yeah, yeah, I can see him.
He's, um...
474
00:55:06,520 --> 00:55:08,120
ADIYA: Going to south?
475
00:55:08,120 --> 00:55:11,480
Yeah, he's going to the south,
he's just this side of the ridge.
476
00:55:18,160 --> 00:55:20,120
The camels come to John.
477
00:55:20,120 --> 00:55:22,120
They are? The camels
are coming to John?
478
00:55:22,120 --> 00:55:23,600
Yes! Really?
479
00:55:28,080 --> 00:55:31,360
JOHN OVER RADIO: Maybe grab the bags
and come down to where I am now
480
00:55:31,360 --> 00:55:35,040
by these bushes, and we'll see if
we can't slip down into the oasis.
481
00:55:40,320 --> 00:55:43,520
HUSHED: This is just amazing.
It's hard fought...
482
00:55:43,520 --> 00:55:46,240
..but the reward is so worth it.
483
00:55:46,240 --> 00:55:49,720
Because right now we're
about 100 metres away...
484
00:55:51,000 --> 00:55:56,080
...from some of the rarest and
hardiest mammals on the planet.
485
00:55:58,640 --> 00:56:00,160
What a privilege.
486
00:56:02,360 --> 00:56:06,320
The team film behaviour
very few people have seen.
487
00:56:07,760 --> 00:56:12,200
Rare images of one of the world's
most endangered creatures.
488
00:56:13,720 --> 00:56:17,040
Once widespread across Central Asia,
489
00:56:17,040 --> 00:56:21,760
this uninhabited desert is
the wild camels' final home.
490
00:56:23,680 --> 00:56:28,320
Were it not for Adiya's team, it
might have disappeared altogether,
491
00:56:28,320 --> 00:56:33,360
but because of their work we may yet
save this icon of the Gobi.
492
00:56:38,720 --> 00:56:41,040
Next time...
493
00:56:41,040 --> 00:56:42,480
..oceans.
494
00:56:45,120 --> 00:56:49,200
All marine life depends on the
continuous movement of water.
495
00:56:51,120 --> 00:56:54,400
Our oceans are linked
by powerful tides...
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00:56:56,240 --> 00:56:58,040
..and where there are currents,
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00:56:58,040 --> 00:56:59,760
there is life.
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00:57:03,960 --> 00:57:07,000
The Open University has
produced a free poster
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00:57:07,000 --> 00:57:09,400
exploring our perfect planet.
500
00:57:09,400 --> 00:57:14,440
To order, please call 0300 303 0901.
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00:57:14,440 --> 00:57:19,320
Or go to bbc.co.uk/perfectplanet
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00:57:19,320 --> 00:57:22,560
and follow the links
to the Open University.
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