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A Perfect Planet.
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We live in a world with
a violent atmosphere.
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00:00:51,860 --> 00:00:53,900
Rain clouds form,
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00:00:53,900 --> 00:00:58,140
and powerful winds carry their
fresh water around the globe.
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00:01:00,620 --> 00:01:06,020
Without this, our perfect planet
simply couldn't function...
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00:01:06,020 --> 00:01:10,820
...for all life on land
depends on the weather.
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00:01:23,580 --> 00:01:27,020
We all know that the weather
can change on a daily,
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00:01:27,020 --> 00:01:29,140
even hourly, basis.
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00:01:31,460 --> 00:01:35,540
But annual weather patterns
have been stable for millennia...
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00:01:36,980 --> 00:01:41,620
...and it's this reliability
on which life depends.
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ANIMALS AND BIRDS CALL
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00:01:47,420 --> 00:01:52,260
Every year in October, the weather
brings a dramatic transformation
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00:01:52,260 --> 00:01:55,620
to this tiny patch
of forest in Zambia.
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00:02:00,500 --> 00:02:03,140
Storm clouds begin to build.
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00:02:06,780 --> 00:02:08,660
THUNDER CRASHES
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00:02:11,500 --> 00:02:17,500
And right on cue, straw-coloured
fruit bats start to appear.
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00:02:23,300 --> 00:02:27,980
They've travelled hundreds, if not
thousands, of miles to be here.
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00:02:35,660 --> 00:02:39,540
And they always arrive
at exactly the same time.
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00:02:42,300 --> 00:02:46,420
They know that these rains
will transform this forest,
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allowing countless
fruit trees to ripen.
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00:02:54,340 --> 00:02:58,700
And the bats gorge on
the new-found abundance.
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00:03:17,420 --> 00:03:20,620
For just 12 weeks every year,
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00:03:20,620 --> 00:03:25,740
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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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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00:04:11,980 --> 00:04:18,060
Africa's largest wildlife migration
entirely dependent on the rain
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00:04:18,060 --> 00:04:21,660
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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evaporate from our oceans,
forming clouds.
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00:04:55,820 --> 00:04:58,740
The spin of the Earth
and the prevailing winds
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00:04:58,740 --> 00:05:01,580
determine where these clouds blow.
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00:05:03,420 --> 00:05:06,980
As a consequence,
some places get less rain...
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...and others much more.
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00:05:13,220 --> 00:05:15,300
The Amazon rainforest...
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00:05:16,740 --> 00:05:18,260
THUNDER CRASHES
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00:05:18,260 --> 00:05:21,380
...one of the wettest
places on Earth.
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00:05:31,380 --> 00:05:33,860
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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00:05:56,380 --> 00:06:00,980
...turning the jungle
into a seasonal wetland.
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00:06:02,860 --> 00:06:07,940
Anything living here
must either climb or swim.
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00:06:12,420 --> 00:06:16,620
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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00:06:34,580 --> 00:06:39,260
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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00:07:06,660 --> 00:07:11,260
As their nest floods,
the colony seems to be doomed.
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But from chaos comes order.
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00:07:24,860 --> 00:07:29,540
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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00:07:37,820 --> 00:07:43,260
Each ant is covered in fine hairs
that trap air against its body.
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As the raft forms, this air creates
a cushion for them all to float on.
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00:07:56,300 --> 00:07:58,820
This is the power of the colony.
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00:08:00,260 --> 00:08:03,620
By working together,
they've become unsinkable.
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00:08:08,060 --> 00:08:10,380
And no-one gets left behind.
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00:08:23,420 --> 00:08:28,180
Pulled from the shallows, the colony
is now at the mercy of the flood.
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00:08:33,940 --> 00:08:36,220
Holding tight to the larvae
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00:08:36,220 --> 00:08:39,460
and keeping their queen hidden
at the centre of the raft,
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00:08:39,460 --> 00:08:43,060
the colony drifts
into deeper water...
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00:08:48,380 --> 00:08:50,860
...where they're vulnerable to fish
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that now swim through
the flooded forest.
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00:09:00,180 --> 00:09:05,220
Those that lose their grip must
get back to the safety of the raft.
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00:09:16,860 --> 00:09:20,860
With jaws that join to
become a surgical needle,
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00:09:20,860 --> 00:09:24,540
this pond skater
could suck an ant dry.
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00:09:35,900 --> 00:09:38,980
But together the colony is strong,
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00:09:38,980 --> 00:09:41,780
and it's time to repel boarders.
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00:09:53,380 --> 00:09:56,620
The ants can travel
like this for weeks.
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00:09:59,620 --> 00:10:03,020
They've even come to depend
on the flood to carry them
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00:10:03,020 --> 00:10:05,380
to new feeding grounds.
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00:10:18,380 --> 00:10:22,620
At last, the ants can
make their raft secure.
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00:10:28,140 --> 00:10:31,380
Surging forward, they
claim their new home...
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...evicting current tenants
without hesitation.
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00:10:39,820 --> 00:10:43,340
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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00:10:56,780 --> 00:11:01,220
until the floodwaters recede
and they can head back underground.
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00:11:14,500 --> 00:11:18,060
The average temperature
of our planet hasn't varied
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00:11:18,060 --> 00:11:22,820
by more than a single degree
Celsius in 10,000 years.
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00:11:24,460 --> 00:11:27,260
This has made our climate stable,
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allowing animals to
fine-tune their behaviour
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00:11:30,380 --> 00:11:33,500
around predictable weather patterns.
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00:11:36,740 --> 00:11:38,980
October in the Amazon.
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00:11:40,860 --> 00:11:43,340
The heaviest rains
have come to an end,
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00:11:43,340 --> 00:11:47,700
and the falling river level
exposes a new landscape.
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00:11:50,580 --> 00:11:55,660
Three weeks ago, these mile-wide
sand bars didn't exist.
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00:11:57,980 --> 00:12:02,180
In another three months,
they'll be back under water.
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00:12:04,820 --> 00:12:10,900
But now they provide a crucial
opportunity for giant river turtles.
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00:12:13,740 --> 00:12:18,460
They've been coming here
at precisely this time
of year for generations.
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00:12:24,340 --> 00:12:28,580
50,000 of them - a quarter
of the world's population.
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00:12:32,820 --> 00:12:34,860
They're all here for one reason.
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00:12:36,540 --> 00:12:39,380
But their window of
opportunity is short,
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00:12:39,380 --> 00:12:42,020
so timing is everything.
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00:12:46,660 --> 00:12:50,940
Scaling the three-metre-high
banks will take this female
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00:12:50,940 --> 00:12:54,980
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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00:13:02,300 --> 00:13:04,500
But others have beaten her to it.
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00:13:14,900 --> 00:13:18,060
The early arrivals
have already claimed
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00:13:18,060 --> 00:13:20,580
nearly every inch of the beach...
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00:13:21,820 --> 00:13:24,420
...and there are still
many more turtles to come.
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00:13:30,780 --> 00:13:33,940
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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00:14:21,140 --> 00:14:24,460
Burying them keeps them
safe from predators,
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and the warm sand
incubates the clutch.
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00:14:34,940 --> 00:14:40,380
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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00:14:55,860 --> 00:14:59,100
Hopefully, she has
got her timing right.
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00:15:12,540 --> 00:15:17,780
Two months on, and the hatchlings
emerge into the world.
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They were laid at the perfect time.
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00:15:31,180 --> 00:15:33,420
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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00:15:50,460 --> 00:15:52,340
THUNDER RUMBLES
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The nesting beach is
beginning to flood.
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00:16:23,060 --> 00:16:26,420
Most hatchlings can escape in time.
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00:16:34,020 --> 00:16:36,420
Those still below ground...
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00:16:37,780 --> 00:16:39,820
...will drown in their nests.
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00:16:44,900 --> 00:16:49,820
For thousands of years, giant river
turtles have timed their breeding
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00:16:49,820 --> 00:16:53,860
around the Amazon's
reliable cycles of rain.
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00:16:57,300 --> 00:17:00,820
But today, our weather is changing.
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00:17:05,260 --> 00:17:12,060
Disastrous early floods like this
used to happen once every 20 years.
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00:17:12,060 --> 00:17:16,820
Now the turtles have to
deal with them every four.
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00:17:31,260 --> 00:17:35,460
Winds may carry huge amounts
of rain to the Amazon,
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00:17:35,460 --> 00:17:40,340
but they don't provide this service
to every corner of the planet.
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00:17:42,100 --> 00:17:48,700
A third of the land receives
less than 25cm of rain a year.
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00:17:52,900 --> 00:17:58,460
Deserts are scarred by desiccating
winds and baked by the sun.
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00:18:01,340 --> 00:18:06,660
But even weather as challenging as
this can be perfect for the locals.
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00:18:12,300 --> 00:18:15,900
As darkness falls in the
coastal deserts of South Africa,
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the dunes come alive...
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00:18:18,500 --> 00:18:20,420
HIGH-PITCHED CALL
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00:18:20,420 --> 00:18:24,260
...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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00:18:47,420 --> 00:18:54,300
Not what you'd expect in a place
that gets just 7cm of rain a year.
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00:18:58,820 --> 00:19:02,740
To survive here, she has
to avoid the heat of the day
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00:19:02,740 --> 00:19:04,780
buried in the sand.
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00:19:07,020 --> 00:19:10,060
But each night, she heads out...
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00:19:10,060 --> 00:19:12,780
..on her hunt for moisture.
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00:19:16,340 --> 00:19:20,700
Short, stumpy legs and a plump body
are ideal for digging...
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00:19:23,820 --> 00:19:27,020
...but not so good
for getting around.
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00:19:31,100 --> 00:19:36,980
She can't hop, so she
waddles across the dunes.
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00:19:44,100 --> 00:19:48,340
The world's slowest steeplechaser.
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Obstacles are tackled
with dogged perseverance.
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00:20:03,660 --> 00:20:08,100
She can travel a whopping
38 metres a night.
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00:20:08,100 --> 00:20:13,700
No mean feat when you're the same
size and shape as a marshmallow.
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00:20:19,260 --> 00:20:21,260
Termites.
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00:20:21,260 --> 00:20:25,220
They are 75% water -
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a meal and a drink in one.
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00:20:32,860 --> 00:20:37,060
But she's not the
most agile predator.
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00:20:38,660 --> 00:20:42,780
Maybe if they just
came a little closer...?
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Oh, dear.
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00:20:50,900 --> 00:20:53,940
Perhaps if they stop moving...?
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00:21:14,580 --> 00:21:16,220
At last.
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00:21:17,500 --> 00:21:21,220
But now she has another challenge.
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00:21:21,220 --> 00:21:25,220
To swallow her food, she
must squash in her eyeballs
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00:21:25,220 --> 00:21:27,740
to push it down her throat.
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00:21:36,380 --> 00:21:38,620
Termites may be juicy,
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00:21:38,620 --> 00:21:42,300
but they don't provide her with
quite enough water to survive.
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00:21:46,060 --> 00:21:48,620
It rarely rains here,
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00:21:48,620 --> 00:21:54,060
but coastal deserts do get another
reliable source of moisture.
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00:22:04,900 --> 00:22:09,580
At night - cool, moist air
is blown in from the ocean,
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00:22:09,580 --> 00:22:13,940
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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00:22:30,340 --> 00:22:35,700
So it's here that she waits,
absorbing moisture through her skin.
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00:22:43,660 --> 00:22:48,340
Rain frogs are so dependent on this
water that they can only survive
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00:22:48,340 --> 00:22:53,180
in places with at least
100 days of fog a year.
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00:22:55,420 --> 00:22:57,700
And on the foggiest nights,
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00:22:57,700 --> 00:23:00,700
when other frogs have
emerged onto the dunes,
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00:23:00,700 --> 00:23:04,780
she takes her opportunity
to find love.
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00:23:12,300 --> 00:23:16,180
Male rain frogs are
smaller than the females,
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00:23:16,180 --> 00:23:21,420
and his stubby legs
make it hard to hold on...
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00:23:21,420 --> 00:23:25,460
..so he glues himself onto her back.
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00:23:35,980 --> 00:23:38,420
Still locked in their embrace,
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00:23:38,420 --> 00:23:42,940
the pair head back beneath the sand,
where they'll lay their eggs,
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00:23:42,940 --> 00:23:46,180
safe from the heat
of the desert sun.
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00:23:54,780 --> 00:23:58,420
But there's one desert
that gets so cold
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00:23:58,420 --> 00:24:02,260
that liquid water
simply can't exist.
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00:24:05,020 --> 00:24:09,060
Winter in Mongolia's Gobi Desert.
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00:24:10,580 --> 00:24:13,460
40 degrees below freezing.
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00:24:16,180 --> 00:24:20,740
One of the driest and most extreme
environments in the world.
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00:24:27,500 --> 00:24:31,180
Most animals can't survive
weather like this...
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00:24:33,540 --> 00:24:36,220
...but there's one unique mammal
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00:24:36,220 --> 00:24:39,420
that manages to eke
out a living here.
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00:24:42,100 --> 00:24:48,740
The Gobi is home to the last 1,000
wild Bactrian camels on Earth...
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00:24:50,820 --> 00:24:53,620
...surviving at the very
edge of what's possible.
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00:24:54,860 --> 00:24:57,100
CAMEL GRUNTS
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00:24:57,100 --> 00:24:59,580
Even camels need moisture,
201
00:24:59,580 --> 00:25:03,380
but any water here
is now frozen solid.
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00:25:07,060 --> 00:25:10,140
It's down to the bull
to find a solution.
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00:25:12,940 --> 00:25:14,780
BULL GRUNTS
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00:25:17,620 --> 00:25:19,700
Setting off with his herd,
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00:25:19,700 --> 00:25:23,100
his search could cover
thousands of square miles.
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00:25:29,020 --> 00:25:33,700
Driving them forward, he can
keep going for days on end.
207
00:25:44,260 --> 00:25:47,660
Herds come together from
across their vast range...
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00:25:49,140 --> 00:25:51,340
...all looking for the same thing.
209
00:26:00,100 --> 00:26:06,380
These long-distance specialists can
smell moisture from 30 miles away...
210
00:26:06,380 --> 00:26:08,620
...and they've picked up a scent.
211
00:26:13,700 --> 00:26:18,100
Even in the Gobi, one of
the driest places on Earth,
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00:26:18,100 --> 00:26:22,020
wind can provide a rare
source of moisture.
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00:26:24,100 --> 00:26:28,380
Snow is blown to this
desert from Siberia.
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00:26:30,180 --> 00:26:33,460
Where it settles is
impossible to predict,
215
00:26:33,460 --> 00:26:35,620
and it may not last long.
216
00:26:42,620 --> 00:26:47,820
But for now, at least, this bull has
found what he's been searching for.
217
00:26:57,740 --> 00:26:59,980
In the cold, dry air,
218
00:26:59,980 --> 00:27:02,020
snow doesn't melt...
219
00:27:03,900 --> 00:27:06,420
...so it must be eaten.
220
00:27:15,660 --> 00:27:19,540
The Gobi's windblown
snow is a lifeline
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00:27:19,540 --> 00:27:22,940
that will sustain his herd
throughout the winter.
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00:27:30,660 --> 00:27:33,980
Even in this most hostile of places,
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00:27:33,980 --> 00:27:38,380
weather still provides
just enough for survival.
224
00:27:50,220 --> 00:27:54,260
The largest, most unpredictable
weather on the planet
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00:27:54,260 --> 00:27:57,300
starts far out at sea.
226
00:28:03,180 --> 00:28:07,020
Hurricanes, typhoons
and tropical cyclones
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00:28:07,020 --> 00:28:10,660
are violent, short-lived megastorms.
228
00:28:12,140 --> 00:28:15,100
But there's a far more
reliable weather system
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00:28:15,100 --> 00:28:17,380
that originates over the ocean...
230
00:28:18,700 --> 00:28:23,140
...one that is eagerly
anticipated by all in its path.
231
00:28:26,140 --> 00:28:32,420
Monsoons are seasonal winds that
blow at the same time each year...
232
00:28:34,900 --> 00:28:39,700
...and they carry colossal amounts
of water from the ocean to the land.
233
00:28:47,140 --> 00:28:48,660
Christmas Island.
234
00:28:50,140 --> 00:28:53,580
A remote speck of rock
in the Indian Ocean.
235
00:28:58,060 --> 00:29:04,460
For the last four months, its forest
interior has remained dry and dusty.
236
00:29:07,740 --> 00:29:11,620
Life here is waiting for change.
237
00:29:14,500 --> 00:29:19,500
In November, the first storms
of the monsoon reach the island.
238
00:29:19,500 --> 00:29:21,940
THUNDER CRASHES
239
00:29:37,060 --> 00:29:41,420
They're a welcome relief for those
that have suffered through the dry.
240
00:29:45,780 --> 00:29:50,900
And they are vital for the island's
most numerous residents.
241
00:30:05,020 --> 00:30:08,380
The red crabs of Christmas Island.
242
00:30:12,580 --> 00:30:15,780
They've spent the dry season
sheltering in damp burrows
243
00:30:15,780 --> 00:30:17,820
beneath the leaf litter.
244
00:30:21,140 --> 00:30:25,340
Crabs breathe through gills
that must be kept moist.
245
00:30:29,780 --> 00:30:33,660
So it's only with the return
of the annual monsoon
246
00:30:33,660 --> 00:30:37,540
that these land crabs
can finally emerge.
247
00:30:44,660 --> 00:30:46,900
With the humidity now high enough,
248
00:30:46,900 --> 00:30:50,540
they can begin an
epic trek to the coast.
249
00:31:03,180 --> 00:31:07,780
Every red crab comes together
from across the island,
250
00:31:07,780 --> 00:31:10,460
and they do so in their millions.
251
00:31:12,860 --> 00:31:15,740
50 million, to be precise.
252
00:31:30,140 --> 00:31:35,420
They've come to release their eggs
that can only develop in the ocean.
253
00:31:36,860 --> 00:31:39,300
There's just one small problem.
254
00:31:40,500 --> 00:31:43,380
They may be crabs...
255
00:31:43,380 --> 00:31:45,580
...but they can't swim.
256
00:31:49,220 --> 00:31:51,500
They're scared of the sea.
257
00:32:05,420 --> 00:32:07,740
But they don't have a choice.
258
00:32:09,140 --> 00:32:13,620
They must release their eggs
on the highest tide.
259
00:32:19,500 --> 00:32:23,580
Each carries around 100,000 eggs,
260
00:32:23,580 --> 00:32:26,260
so over just two or three nights,
261
00:32:26,260 --> 00:32:29,380
trillions are released
into the ocean.
262
00:32:31,700 --> 00:32:35,340
Though some are more
successful than others.
263
00:33:00,580 --> 00:33:05,180
Once their work is done,
the crabs will return to the forest.
264
00:33:22,100 --> 00:33:24,900
Then, four weeks later,
265
00:33:24,900 --> 00:33:27,140
on the next highest tide...
266
00:33:32,580 --> 00:33:34,900
...having hatched out to sea,
267
00:33:34,900 --> 00:33:39,940
a new generation of red crabs
returns to the same beach.
268
00:33:42,180 --> 00:33:44,060
In good years like this one,
269
00:33:44,060 --> 00:33:47,860
countless millions arrive back on
the shores of Christmas Island,
270
00:33:47,860 --> 00:33:50,500
turning the beaches red.
271
00:34:07,580 --> 00:34:12,260
Like their parents, they also need
moisture in the air to breathe.
272
00:34:14,900 --> 00:34:17,180
So before the rains move on,
273
00:34:17,180 --> 00:34:22,860
the young crabs must undertake their
own epic journey into the forest,
274
00:34:22,860 --> 00:34:26,660
where they'll wait out
the next few months of dry.
275
00:34:46,780 --> 00:34:49,060
The Christmas Island crab -
276
00:34:49,060 --> 00:34:53,380
entirely reliant on the
return of the monsoon.
277
00:35:04,300 --> 00:35:10,340
The annual rhythms of the weather
shape life across our planet.
278
00:35:12,780 --> 00:35:15,020
In some parts of the world,
279
00:35:15,020 --> 00:35:19,260
seasonal cycles of wet and dry
can bring dramatic change.
280
00:35:21,900 --> 00:35:24,780
And there are few places
where this is more apparent
281
00:35:24,780 --> 00:35:26,980
than southern Africa.
282
00:35:34,020 --> 00:35:36,340
The Zambezi River.
283
00:35:38,020 --> 00:35:44,300
It flows across six countries and
drains half a million square miles.
284
00:35:58,340 --> 00:36:00,940
At the peak of the wet season,
285
00:36:00,940 --> 00:36:07,540
5,000 tonnes of water cascade
over Victoria Falls every second.
286
00:36:10,100 --> 00:36:13,500
And yet, each year
when the rains stop,
287
00:36:13,500 --> 00:36:16,780
these falls run dry.
288
00:36:24,500 --> 00:36:28,460
It's almost as if someone
turns off the tap.
289
00:36:33,620 --> 00:36:35,060
May...
290
00:36:38,460 --> 00:36:40,100
..December.
291
00:36:43,220 --> 00:36:44,980
Wet season...
292
00:36:48,460 --> 00:36:50,260
..dry season.
293
00:36:53,180 --> 00:36:56,980
It's happened like this
for thousands of years.
294
00:37:03,100 --> 00:37:08,140
But there are signs that
the weather here is changing.
295
00:37:08,140 --> 00:37:12,900
In recent years, the volume of
water flowing over Victoria Falls
296
00:37:12,900 --> 00:37:15,460
has dropped by half.
297
00:37:19,660 --> 00:37:23,020
A concern for animals
that have come to rely on
298
00:37:23,020 --> 00:37:26,620
the natural rhythms of wet and dry.
299
00:37:39,700 --> 00:37:45,540
Zambia's Luangwa River is a
major tributary of the Zambezi.
300
00:37:47,380 --> 00:37:50,500
Every year, as the
dry season takes hold,
301
00:37:50,500 --> 00:37:53,660
it dwindles into pools.
302
00:37:57,100 --> 00:38:00,540
Accommodation starts to
get tight for the locals.
303
00:38:00,540 --> 00:38:02,380
HIPPO SNORTS
304
00:38:04,460 --> 00:38:09,500
With no other water around, the
river becomes a magnet for visitors.
305
00:38:15,420 --> 00:38:20,060
Millions of red-billed quelea
flock to the water's edge.
306
00:38:24,380 --> 00:38:28,180
These seed eaters need
to drink every day...
307
00:38:47,140 --> 00:38:49,860
...and Nile crocodiles know it.
308
00:38:51,380 --> 00:38:53,700
They may not have
eaten for six months.
309
00:38:54,940 --> 00:38:59,820
For them, the dry season is
the start of the good times.
310
00:39:09,380 --> 00:39:14,140
And they are not the only ones
to depend on this time of year.
311
00:39:19,420 --> 00:39:23,140
Carmine bee-eaters have
flown hundreds of miles
312
00:39:23,140 --> 00:39:25,460
from the rainforests of the Congo...
313
00:39:27,140 --> 00:39:30,380
...arriving at the
peak of the dry season,
314
00:39:30,380 --> 00:39:35,300
when steep sandbanks are
exposed by the falling water.
315
00:39:41,700 --> 00:39:44,420
They're a perfect place to nest,
316
00:39:44,420 --> 00:39:47,260
out of reach of
predators from above.
317
00:39:56,580 --> 00:40:02,020
Bee-eater burrows can extend for
two metres into the soft river sand.
318
00:40:03,620 --> 00:40:06,460
Already home to 6,000 nests,
319
00:40:06,460 --> 00:40:11,100
real estate at Bee-eater Towers
is in high demand.
320
00:40:15,060 --> 00:40:18,900
But it pays not to build
too close to the neighbours.
321
00:40:29,500 --> 00:40:34,460
As more birds arrive, competition
for the best nesting sites heats up.
322
00:40:45,500 --> 00:40:47,500
It's thirsty work.
323
00:40:58,340 --> 00:41:02,180
In the sudden commotion,
they're vulnerable from below...
324
00:41:04,180 --> 00:41:05,820
...and above.
325
00:41:09,740 --> 00:41:12,300
African fish eagles.
326
00:41:20,660 --> 00:41:23,740
They are permanent residents here.
327
00:41:23,740 --> 00:41:27,700
But at this time of the year,
they don't just eat fish.
328
00:41:32,660 --> 00:41:36,220
The safest place to be
is inside a burrow.
329
00:41:37,940 --> 00:41:43,540
But an eagle fly-by sends shock
waves of panic through the colony.
330
00:41:56,420 --> 00:42:01,260
The eagles' strategy is to pin
their prey against the river bank.
331
00:42:05,340 --> 00:42:08,100
With the colony in disarray,
332
00:42:08,100 --> 00:42:10,460
the predators have the advantage.
333
00:42:50,700 --> 00:42:55,100
These fish eagles also choose
to breed in the dry season,
334
00:42:55,100 --> 00:42:59,340
because they need the bee-eaters
as food for their chicks.
335
00:43:06,620 --> 00:43:11,540
But this year's dry season
shows no sign of letting up.
336
00:43:19,180 --> 00:43:22,540
Parts of the river are now bone-dry,
337
00:43:22,540 --> 00:43:26,380
forcing huge male hippos
from their home.
338
00:43:36,740 --> 00:43:39,020
With nowhere left to turn,
339
00:43:39,020 --> 00:43:42,420
they must converge on the few
remaining patches of water...
340
00:43:42,420 --> 00:43:44,300
HIPPO GRUNTS
341
00:43:44,300 --> 00:43:47,100
..but these are already occupied.
342
00:43:59,940 --> 00:44:03,540
The resident bull here can't
tolerate another big male
343
00:44:03,540 --> 00:44:06,060
in his shrinking pool.
344
00:44:08,500 --> 00:44:10,460
HIPPO BELLOWS
345
00:44:36,500 --> 00:44:39,420
The newcomer is banished.
346
00:44:50,500 --> 00:44:53,580
Still the sun bakes the land...
347
00:44:56,660 --> 00:44:59,820
...with devastating consequences.
348
00:45:31,740 --> 00:45:34,740
Hundreds of nests are wiped out.
349
00:45:43,140 --> 00:45:47,180
Southern Africa has
experienced dry seasons
350
00:45:47,180 --> 00:45:49,340
for thousands of years.
351
00:45:50,860 --> 00:45:53,860
But this is something different.
352
00:45:58,940 --> 00:46:04,620
Record high temperatures and the
lowest rainfall in nearly 40 years
353
00:46:04,620 --> 00:46:09,700
have thrown parts of Africa into one
of the worst droughts in a century.
354
00:46:17,060 --> 00:46:18,860
THUNDER CRASHES
355
00:46:25,540 --> 00:46:30,820
Across the planet, our once
stable climate is changing.
356
00:46:35,700 --> 00:46:37,940
Weather is less reliable...
357
00:46:40,380 --> 00:46:43,580
...and is getting more extreme.
358
00:46:47,300 --> 00:46:50,140
Wildfires are becoming
more frequent.
359
00:47:05,900 --> 00:47:08,540
Droughts are more intense.
360
00:47:19,380 --> 00:47:23,500
And storms are more ferocious.
361
00:47:27,740 --> 00:47:32,980
All this from a recent rise
in global temperatures
362
00:47:32,980 --> 00:47:35,820
of just a single degree Celsius.
363
00:47:37,620 --> 00:47:40,940
Yet if climate change
continues unchecked,
364
00:47:40,940 --> 00:47:46,980
we may see a rise of almost five
degrees by the end of the century.
365
00:47:48,940 --> 00:47:53,500
We can only imagine what
this will do to our weather.
366
00:48:12,220 --> 00:48:15,660
There are a few things more daunting
for the wildlife film crew
367
00:48:15,660 --> 00:48:20,540
than the prospect of finding
a very rare animal in a vast area.
368
00:48:24,700 --> 00:48:28,660
But that is the mission
in Mongolia's Gobi Desert -
369
00:48:28,660 --> 00:48:32,220
to film an animal
numbering less than 500
370
00:48:32,220 --> 00:48:35,940
in a wilderness of
half a million square miles.
371
00:48:41,860 --> 00:48:45,060
We're all loaded up. We got 40 cases
of gear, we got nine vehicles.
372
00:48:45,060 --> 00:48:47,340
We're off,
we're heading to the Gobi.
373
00:48:50,820 --> 00:48:53,260
DAVID ATTENBOROUGH:
From the capital, Ulaanbaatar,
374
00:48:53,260 --> 00:48:56,260
it'll take the team
five days to cross Mongolia
375
00:48:56,260 --> 00:48:58,740
in the depths of winter -
376
00:48:58,740 --> 00:49:02,580
travelling in a convoy
of large camping trucks,
377
00:49:02,580 --> 00:49:04,580
home for the next five weeks.
378
00:49:22,500 --> 00:49:28,340
1,000 miles later, the convoy
reaches the Gobi and makes camp.
379
00:49:32,620 --> 00:49:35,700
Well, we have woken up
on our first morning,
380
00:49:35,700 --> 00:49:38,580
and it's about an hour-and-a-half
before sunrise,
381
00:49:38,580 --> 00:49:43,260
and rather foolishly we let the
fire go out last night, so it's...
382
00:49:43,260 --> 00:49:45,460
..a cool minus 20 in here.
383
00:49:45,460 --> 00:49:49,100
Everything's frozen solid -
toothpaste, hot sauce for breakfast,
384
00:49:49,100 --> 00:49:51,140
even the AP's pee bottle...
385
00:49:51,140 --> 00:49:52,940
..so that's nice.
386
00:49:55,620 --> 00:49:59,020
Finding a scarce animal in
an area the size of Belgium
387
00:49:59,020 --> 00:50:01,900
is clearly no small task...
388
00:50:01,900 --> 00:50:04,980
GARBLED RADIO CONVERSATION
389
00:50:04,980 --> 00:50:08,860
...but impossible without
the help of local researchers.
390
00:50:10,700 --> 00:50:15,100
Each day, the team scour
thousands of square miles.
391
00:50:15,100 --> 00:50:17,540
It's a huge area,
and there's only 450 camels,
392
00:50:17,540 --> 00:50:20,860
so it really is a bit like
a needle in a haystack.
393
00:50:22,100 --> 00:50:25,300
A truly enormous haystack.
394
00:50:29,540 --> 00:50:31,620
450 camels...
ADIYA LAUGHS
395
00:50:31,620 --> 00:50:33,140
...28,000 square miles.
396
00:50:33,140 --> 00:50:35,220
Easy, yeah? Yeah.
397
00:50:35,220 --> 00:50:38,260
And when scanning the
horizon for camels,
398
00:50:38,260 --> 00:50:40,260
mistakes are all too easy.
399
00:50:40,260 --> 00:50:41,700
Another bush.
400
00:50:42,780 --> 00:50:45,060
A bush. Sorry.
401
00:50:46,580 --> 00:50:49,420
Sometimes there's not
even a bush to look at.
402
00:50:49,420 --> 00:50:51,020
See anything? Nothing.
403
00:50:52,300 --> 00:50:54,300
Another hill climbed.
404
00:50:54,300 --> 00:50:56,100
Another trail followed.
405
00:50:56,100 --> 00:50:58,380
Another dead end.
406
00:50:58,380 --> 00:51:01,220
Thankfully, the experts
remain positive.
407
00:51:01,220 --> 00:51:03,020
I hope you can see them soon.
408
00:51:03,020 --> 00:51:04,620
Yeah, yeah. Please.
409
00:51:07,500 --> 00:51:09,300
Two weeks since leaving the UK.
410
00:51:09,300 --> 00:51:11,780
I'm just hoping that we haven't...
411
00:51:11,780 --> 00:51:13,660
...been slightly
overambitious on this one.
412
00:51:13,660 --> 00:51:16,700
Getting slightly worried it
might actually be impossible.
413
00:51:18,460 --> 00:51:20,180
ED SIGHS
414
00:51:22,100 --> 00:51:23,940
Hmm... Good support there, thanks.
415
00:51:25,300 --> 00:51:29,260
Eventually, the team
spot their first camel...
416
00:51:29,260 --> 00:51:32,140
..but, unfortunately,
it spotted them first.
417
00:51:33,500 --> 00:51:35,540
Very far away.
418
00:51:35,540 --> 00:51:38,900
Poaching has made the
surviving camels very nervous,
419
00:51:38,900 --> 00:51:42,780
and once they start running
they can keep going for miles.
420
00:51:45,060 --> 00:51:47,300
WIND HOWLS
421
00:51:47,300 --> 00:51:49,740
And when the winter winds kick off,
422
00:51:49,740 --> 00:51:52,620
all signs of camel vanish.
423
00:51:52,620 --> 00:51:55,180
So, for about the past 24 hours,
we've been experiencing
424
00:51:55,180 --> 00:51:58,100
the Gobi winds. It's been gusting
up to 70mph hour all night,
425
00:51:58,100 --> 00:52:00,460
and the temps have probably
been down to almost -50
426
00:52:00,460 --> 00:52:03,540
with the wind-chill. We just have to
hunker down, we can't film in this.
427
00:52:07,660 --> 00:52:11,860
When the gale eases,
the search reveals new hope.
428
00:52:13,340 --> 00:52:15,340
We got a load of fresh
camel tracks here.
429
00:52:16,740 --> 00:52:20,140
And all tracks head one way -
430
00:52:20,140 --> 00:52:24,620
towards the even more remote
mountainous southern Gobi.
431
00:52:28,780 --> 00:52:32,420
The team must decide
if they should follow.
432
00:52:32,420 --> 00:52:36,180
Do you think that landscape
is likely to be better for us?
433
00:52:36,180 --> 00:52:39,100
More camels and
closer encounters or...?
434
00:52:39,100 --> 00:52:41,060
What's your gut telling you?
435
00:52:43,260 --> 00:52:45,420
Because of the wintertime,
436
00:52:45,420 --> 00:52:48,100
we need to see some snow... Mm.
437
00:52:48,100 --> 00:52:49,260
...to see camels.
438
00:52:50,700 --> 00:52:55,300
To survive in this waterless desert,
the camels depend on finding snow.
439
00:52:56,980 --> 00:52:59,300
So, with none in sight,
440
00:52:59,300 --> 00:53:03,660
the team decide to try their luck
in the icy mountains to the south.
441
00:53:08,140 --> 00:53:09,980
Sure enough, there's snow -
442
00:53:09,980 --> 00:53:11,740
and lots of it.
443
00:53:15,100 --> 00:53:19,340
But the larger camping trucks
struggle in the mountainous terrain,
444
00:53:19,340 --> 00:53:22,580
and the team are forced
to go on without them,
445
00:53:22,580 --> 00:53:27,700
leaving them somewhat more
exposed to the winter conditions.
446
00:53:27,700 --> 00:53:30,020
It's been down to
-25 over the last week.
447
00:53:30,020 --> 00:53:33,380
So very thin canvas tents
will be a whole new experience
448
00:53:33,380 --> 00:53:36,020
in the Gobi Desert for us.
449
00:53:36,020 --> 00:53:39,540
I'm wearing, currently,
two pairs of trousers, thermals,
450
00:53:39,540 --> 00:53:43,420
thermals on top, two pairs of
jumpers, three coats, two hats...
451
00:53:43,420 --> 00:53:45,940
So I THINK I should be all right.
452
00:53:45,940 --> 00:53:47,100
HE EXHALES
453
00:53:49,380 --> 00:53:51,020
TOBY: You all right, Eddie?
454
00:53:51,020 --> 00:53:52,700
Oh, I'm terrific, yeah.
455
00:53:52,700 --> 00:53:55,100
HE LAUGHS
Really terrific!
456
00:53:55,100 --> 00:53:57,660
HE SIGHS CONTENTEDLY
I'm all cosy.
457
00:53:59,140 --> 00:54:00,580
I'm not. I'm cold.
458
00:54:00,580 --> 00:54:02,020
Really cold!
459
00:54:06,420 --> 00:54:11,740
As Adiya predicted,
with snow come camels.
460
00:54:11,740 --> 00:54:14,540
The signs are everywhere.
461
00:54:17,860 --> 00:54:19,700
But having travelled so far,
462
00:54:19,700 --> 00:54:22,740
they can't risk anything
ruining this chance.
463
00:54:22,740 --> 00:54:26,220
HUSHED: Camels don't seem
to like the cars so...
464
00:54:26,220 --> 00:54:27,700
...now we walk.
465
00:54:29,860 --> 00:54:32,180
We've been walking for
about five miles now,
466
00:54:32,180 --> 00:54:34,500
and hiking across this landscape,
467
00:54:34,500 --> 00:54:38,140
it really does give you a new-found
respect for the camels.
468
00:54:43,660 --> 00:54:46,900
We've seen some camels
way out on the plain here,
469
00:54:46,900 --> 00:54:51,300
but in order not to scare them,
John's going to head out on his own.
470
00:55:04,140 --> 00:55:06,980
Yeah, yeah, I can see him.
He's, um...
471
00:55:06,980 --> 00:55:08,620
ADIYA: Going to south?
472
00:55:08,620 --> 00:55:12,020
Yeah, he's going to the south,
he's just this side of the ridge.
473
00:55:18,660 --> 00:55:20,620
The camels come to John.
474
00:55:20,620 --> 00:55:22,620
They are? The camels
are coming to John?
475
00:55:22,620 --> 00:55:24,020
Yes! Really?
476
00:55:28,620 --> 00:55:31,900
JOHN OVER RADIO: Maybe grab the bags
and come down to where I am now
477
00:55:31,900 --> 00:55:35,500
by these bushes, and we'll see if
we can't slip down into the oasis.
478
00:55:40,940 --> 00:55:43,940
HUSHED: This is just amazing.
It's hard fought...
479
00:55:43,940 --> 00:55:46,820
..but the reward is so worth it.
480
00:55:46,820 --> 00:55:50,180
Because right now we're
about 100 metres away...
481
00:55:51,580 --> 00:55:56,540
...from some of the rarest and
hardiest mammals on the planet.
482
00:55:59,180 --> 00:56:00,580
What a privilege.
483
00:56:02,900 --> 00:56:06,820
The team film behaviour
very few people have seen.
484
00:56:08,340 --> 00:56:12,700
Rare images of one of the world's
most endangered creatures.
485
00:56:14,220 --> 00:56:17,660
Once widespread across Central Asia,
486
00:56:17,660 --> 00:56:22,260
this uninhabited desert is
the wild camels' final home.
487
00:56:24,180 --> 00:56:28,860
Were it not for Adiya's team, it
might have disappeared altogether,
488
00:56:28,860 --> 00:56:33,860
but because of their work we may yet
save this icon of the Gobi.
489
00:56:39,180 --> 00:56:41,580
Next time...
490
00:56:41,580 --> 00:56:42,980
..oceans.
491
00:56:45,660 --> 00:56:49,740
All marine life depends on the
continuous movement of water.
492
00:56:51,620 --> 00:56:54,820
Our oceans are linked
by powerful tides...
493
00:56:56,660 --> 00:56:58,500
..and where there are currents,
494
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there is life.
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00:57:04,460 --> 00:57:07,500
The Open University has
produced a free poster
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exploring our perfect planet.
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To order, please call 0300 303 0901.
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Or go to bbc.co.uk/perfectplanet
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and follow the links
to the Open University.
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