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DAVID ATTENBOROUGH:
The power of the sun drives the seasons,
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transforming our planet.
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00:00:11,967 --> 00:00:15,437
Vast movements of ocean and air currents
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00:00:15,527 --> 00:00:18,519
bring dramatic change
throughout the year.
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00:00:22,727 --> 00:00:26,606
And in a few special places,
these seasonal changes
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00:00:26,687 --> 00:00:31,203
create some of the greatest
wildlife spectacles on Earth.
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00:00:34,287 --> 00:00:36,847
The most dramatic event
in the world's oceans
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happens off the eastern shores
of South Africa.
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These cool waters create
the perfect conditions
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for a spectacle of epic proportions.
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00:00:56,647 --> 00:01:00,526
And everything revolves
around the humble sardine.
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00:01:04,807 --> 00:01:08,641
Each year millions of them
are swept up Africa's coast
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on a desperate winter journey.
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00:01:16,247 --> 00:01:20,320
Following them comes what will become
the biggest army of predators
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anywhere on the planet.
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The climax to this chase depends
on many crucial elements coming together
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for one brief moment in time.
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This can well claim to be
the greatest ''shoal'' on Earth.
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In the deep water
off the southern tip of Africa
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lie the rich fishing grounds
of the Agulhas Bank.
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It's home to billions of sardines.
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They live in immense shoals as
defence against their many predators.
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Moving together as one in a shoal
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gives an individual sardine
its best chance of survival.
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Sardines are so numerous,
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they're on the menu
of most fish-eating predators here.
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It's summer, and the sardines are lost
in the vastness of the ocean.
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The shoals are so dispersed
they're hard to find.
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Common dolphins
are specialist sardine hunters.
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Dolphins aren't
the only ones on their trail.
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Gannets also rely on a diet of sardines.
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The best way for them to find the shoals
is to follow the dolphins.
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When the fish are far out to sea,
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the dolphins need great perseverance
to track them down.
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The dolphins use
their own form of sonar,
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sending out a stream
of clicks and whistles,
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listening for returning echoes.
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(CLICKING)
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At last they've found
what they're looking for.
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Working as a team,
the dolphins isolate a group of fish
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and corral them into a tight ball
close to the surface.
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The gannets can now make their move.
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Gannets can't dive deep,
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so they must rely on dolphins
to keep the sardines near the surface.
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The feeding frenzy is short-lived.
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Most of the shoal escapes to the deep
and the hunters are left still hungry.
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It's December,
the height of the southern summer,
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and the sardines have the advantage.
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With the shoals dispersed,
life is hard for all the predators.
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But in six months' time,
if conditions are right,
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the scene will be set for
astonishing and sustained drama.
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For a few short weeks each winter,
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cold ocean currents can sweep
great shoals of sardines up the coast.
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Trapped close to shore
within this corridor of cool water,
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the fish are vulnerable and
their predators will follow in droves.
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If it happens,
this will be the Sardine Run,
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one of nature's great events,
unique to these shores of South Africa.
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But for this epic event to take place,
many elements have to come together,
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00:07:01,887 --> 00:07:05,960
and with our changing climate
they're less predictable every year.
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00:07:08,727 --> 00:07:12,606
For the predators,
the winter Sardine Run, if it happens,
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can make the difference
between life and death.
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Dolphins rely on the easy hunting
during the run to wean their calves.
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But the omens aren't good.
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Last year the sardines
didn't run at all.
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Gannets follow the same pattern.
They have their chicks in summer,
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so they, too, leave the nest
in time for the Sardine Run.
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This is Bird Island,
just off the Eastern Cape,
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the biggest gannet colony in the world.
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No less than 1 00,000 breeding pairs
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come here every summer
to have their young.
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These incredible numbers
show the wealth of life
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the annual Sardine Run can support.
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They also show how many lives
may be in jeopardy
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if the sardines don't run.
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00:08:41,287 --> 00:08:44,836
Right now the African summer
is taking its toll.
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00:08:44,927 --> 00:08:48,715
With temperatures soaring
and no cover on these exposed islands,
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the birds are in danger of overheating.
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The young are especially vulnerable.
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They have to be fed every day.
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00:09:10,887 --> 00:09:15,244
Even with both parents taking turns,
it's an exhausting task.
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00:09:38,007 --> 00:09:42,364
In summer the sardines are
a long way out to sea.
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The birds fly hundreds of miles
in search of a meal.
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Once they've sighted their target,
they plunge from heights of 30 metres...
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striking the water at 60 mph.
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00:10:25,047 --> 00:10:29,040
Every dive subjects them
to enormous forces.
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00:10:36,247 --> 00:10:39,444
The slightest miscalculation
could be fatal.
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Gannets dive no deeper than 1 0 metres,
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so once again they rely on the dolphins
to keep their prey near the surface.
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But with so much traffic, there's
always the danger of a collision.
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This one has broken her neck.
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Her death will mean
that back on the colony
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her chick will probably starve.
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The rest make the long flight home
with their catch.
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One partner stays on the island
to guard their chick.
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The pair welcome each other
with a ritualised greeting.
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They have a strong bond
and many couples mate for life.
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During the hours of daylight
the sardines stay deep
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in an attempt to avoid their predators.
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As the sun sets, the little fish
themselves can begin to feed.
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00:12:35,287 --> 00:12:38,836
They swim upwards
to sieve the water for plankton,
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microscopic plants and animals.
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00:12:55,207 --> 00:12:59,997
At daybreak they sink once more
into the safety of the deep.
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00:13:13,807 --> 00:13:17,800
It's not just dolphins and gannets
that rely on sardines.
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There are other,
more mysterious predators.
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The Bryde's whale
hardly breaks the surface to breathe
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and never so much as shows a tail fluke.
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For a 1 5-metre whale,
they can vanish with remarkable ease.
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We know little
about these stealthy leviathans,
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other than that they are
sardine-hunters, too.
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Summer is a lean time
for the Bryde's whale,
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as it is for all the predators.
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00:14:31,607 --> 00:14:33,837
Sharks follow the same patterns,
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tracking the shoals offshore
through the summer,
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waiting for the winter Sardine Run
when the hunting will be easier.
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00:14:43,927 --> 00:14:45,838
But being cold-blooded,
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00:14:45,927 --> 00:14:50,523
they don't have the high energy demands
of the whales, dolphins and gannets.
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00:14:57,727 --> 00:15:00,685
All the predators
have to endure the lean months,
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relying on the southern winter in June
to bring a change in their fortunes.
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00:15:10,007 --> 00:15:14,842
Now the changing seasons
create a switch in the ocean currents.
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00:15:15,487 --> 00:15:17,205
As summer gives way to autumn,
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the southerly-flowing
warm current weakens
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00:15:19,847 --> 00:15:24,557
and cold Antarctic water
pushes further north, nearer to land.
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00:15:27,007 --> 00:15:30,602
The sardines are carried along
by these cool waters
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00:15:30,687 --> 00:15:32,917
and pushed closer to shore.
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00:15:37,487 --> 00:15:39,955
If these ocean currents
continue to change,
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the Sardine Run should be
only three months away.
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00:15:48,687 --> 00:15:53,078
It's time for the gannet chicks
to leave the safety of their colony.
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Parents stop feeding their young
when they're three months old.
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This forces the chicks
to take to the sea.
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00:16:12,607 --> 00:16:17,476
The young have enough fat reserves
to survive for just 1 0 days.
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00:16:17,967 --> 00:16:19,559
And in this brief window,
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they must learn how to fly
and hunt for themselves.
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00:16:26,967 --> 00:16:30,642
This is the most critical time
in a gannet's life.
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00:16:30,727 --> 00:16:33,366
Failure will mean starvation.
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To prepare for their maiden flight,
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00:16:47,847 --> 00:16:51,635
they test their wings
and strengthen their flying muscles.
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00:17:04,567 --> 00:17:09,516
Eventually, hunger drives them
onwards and upwards.
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00:17:26,007 --> 00:17:29,363
Some get up and away first time.
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00:17:39,407 --> 00:17:43,480
But many don't make it
past the crashing surf.
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00:18:11,487 --> 00:18:14,957
Some bedraggled chicks
struggle back to shore.
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But for others,
the pounding has been too much.
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Fewer than half
of all the chicks on this colony
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survive their first three months
of life.
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The coast of South Africa
is an unforgiving place.
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00:19:23,647 --> 00:19:27,117
The baby dolphins
are still dependent on their mothers.
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00:19:27,207 --> 00:19:31,200
They suckle for six months before they,
like the young gannets,
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have to start fishing for themselves.
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00:19:40,807 --> 00:19:43,799
There is such an abundance of fish
during the Sardine Run,
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that even the calves can catch some and
so begin to learn their hunting skills.
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00:19:56,047 --> 00:20:00,677
But the Sardine Run
might not even happen this year.
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00:20:05,247 --> 00:20:09,718
For now the dolphins will have to
continue to scour the vast ocean.
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00:20:29,767 --> 00:20:34,557
Back at the coast, other youngsters
are getting ready to go it alone.
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Cape fur seals are also waiting
for the sardines to come close to shore.
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But seals have a broad diet,
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00:20:58,127 --> 00:21:01,324
so they can make the most
of other feeding opportunities
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00:21:01,407 --> 00:21:04,126
until the sardines come within range.
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00:21:09,007 --> 00:21:13,285
Young seals are forced from the colony
by the dominant males.
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00:21:24,487 --> 00:21:29,766
Once they're cast out, the adolescents
roam the coastline looking for food.
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00:21:45,647 --> 00:21:49,799
They won't turn their noses up
at a plump young gannet.
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00:21:58,447 --> 00:22:00,517
Hungry seals patrol the surf,
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ready to pick off any birds that
don't get airborne straight away.
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00:22:07,007 --> 00:22:11,000
When the wind is light, the gannet
chicks are stuck on the island.
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00:22:19,447 --> 00:22:21,563
Surely they're safe here?
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00:22:22,527 --> 00:22:27,555
But even on land the seal is
surprisingly fast on his flippers.
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00:23:29,207 --> 00:23:32,722
In this one season,
on this one colony alone,
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seals kill up to1 0,000 fledglings.
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00:23:38,167 --> 00:23:41,204
And, as ever,
it all comes down to sardines,
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for the seals are only after the fish
within the stomach of their victims.
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00:23:50,927 --> 00:23:53,760
For the young birds
who do make it past the seals,
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there are fresh challenges.
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Learning the skills of their parents.
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First they have to find their quarry,
the sardine shoals.
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And the best way to do that
is to follow the expert trackers.
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They're hungry. It's been days
since their parents last fed them.
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As the search goes on,
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the chicks are learning
the most sophisticated
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survival technique of all -
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how to harness the expertise
of another species.
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00:24:56,367 --> 00:24:57,846
After a long search,
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00:24:57,927 --> 00:25:01,124
the dolphins have found
a small school of fish.
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00:25:05,087 --> 00:25:10,400
They drive the sardines to the surface
and within range of the young gannets.
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00:25:10,487 --> 00:25:14,480
Now, quickly, they have to learn
the art of the plunge-dive.
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00:25:21,087 --> 00:25:22,566
But there's a problem.
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00:25:22,647 --> 00:25:26,322
The opportunistic seals
have found the fish, too.
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00:25:30,807 --> 00:25:32,957
The young gannets
have a daunting choice.
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00:25:33,047 --> 00:25:36,642
To risk diving with the enemy
or to starve.
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00:25:38,007 --> 00:25:42,159
If they don't take their chances soon,
there will be nothing left.
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00:25:55,567 --> 00:25:56,602
They're in luck.
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00:25:56,687 --> 00:26:01,078
With sardines back on the menu,
the seals ignore the gannets.
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00:26:11,487 --> 00:26:13,842
As ever, the dolphins have
done the hard work
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00:26:13,927 --> 00:26:15,326
of rounding up the fish,
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00:26:15,407 --> 00:26:18,717
and now a host of other predators
take advantage.
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00:26:21,607 --> 00:26:25,725
With the shoal diminishing
by the second, competition is fierce.
194
00:26:26,567 --> 00:26:29,877
But there is still time
for a mighty intruder.
195
00:26:43,487 --> 00:26:47,924
The Bryde's whale
devours the entire ball of fish.
196
00:26:49,287 --> 00:26:51,926
Until the Sardine Run starts in earnest,
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00:26:52,007 --> 00:26:56,159
these minor skirmishes are
mere preludes to the main event.
198
00:26:57,807 --> 00:27:03,006
But winter is finally on the way.
The cold current pushes further north.
199
00:27:03,927 --> 00:27:07,476
This cool water
forces its way up the coast.
200
00:27:07,847 --> 00:27:10,236
If it continues to flow northwards,
201
00:27:10,327 --> 00:27:13,717
it will carry
great shoals of sardines with it.
202
00:27:18,647 --> 00:27:22,686
The predators begin to gather,
in anticipation of a feast.
203
00:27:30,127 --> 00:27:34,359
Sardines can't tolerate water
above 20 degrees centigrade.
204
00:27:34,447 --> 00:27:37,803
So unless the cool water
penetrates further up the coast,
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00:27:37,887 --> 00:27:42,005
the fish won't move and
the annual run just won't happen.
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00:27:44,767 --> 00:27:47,759
Perhaps climate change
has made its mark here.
207
00:27:47,847 --> 00:27:51,760
The waters have stayed too warm,
stalling the movement of fish.
208
00:27:52,167 --> 00:27:55,796
There hasn't been a sardine run
for the past two years.
209
00:28:03,767 --> 00:28:06,804
The entire fleet is becalmed.
210
00:28:40,887 --> 00:28:44,323
A winter storm rolls in
from the Antarctic,
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00:28:44,407 --> 00:28:47,843
battering the Cape, bringing cold water.
212
00:29:00,607 --> 00:29:02,120
Driven by their hunger,
213
00:29:02,207 --> 00:29:06,359
gannets still try to hunt
in these dangerous conditions.
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00:29:11,967 --> 00:29:14,037
In fact, this wild weather
215
00:29:14,127 --> 00:29:17,119
is just what all the predators
have been waiting for.
216
00:29:17,207 --> 00:29:19,880
For them, it's a perfect storm.
217
00:29:22,407 --> 00:29:26,764
It has pushed a narrow tongue
of colder water up the coast.
218
00:29:27,047 --> 00:29:31,325
This chilly current carries wave
after wave of sardines with it.
219
00:29:31,927 --> 00:29:36,000
Hemmed in by the land on one side
and warm water on the other,
220
00:29:36,087 --> 00:29:38,726
the sardines are
being drawn into a trap.
221
00:29:43,167 --> 00:29:46,842
Nature is playing a cruel trick
on these unfortunate fish,
222
00:29:46,927 --> 00:29:50,078
as they'll get no benefit
from their mass voyage.
223
00:29:52,367 --> 00:29:55,359
They're slaves
to the cold ocean currents.
224
00:29:57,967 --> 00:30:02,483
More than 500 million fish
are swimming towards disaster,
225
00:30:02,567 --> 00:30:06,196
and yet this is just a tenth
of the sardine population.
226
00:30:06,567 --> 00:30:08,239
The run is on.
227
00:30:19,367 --> 00:30:22,279
Ahead, an ambush is being prepared.
228
00:30:26,247 --> 00:30:28,203
As the seas begin to calm,
229
00:30:28,287 --> 00:30:31,359
the dolphins relocate
the sardine shoals.
230
00:30:44,767 --> 00:30:49,318
As they track up the coast,
the pods unite, combining forces.
231
00:30:58,207 --> 00:31:01,404
They form super-pods
of incredible numbers,
232
00:31:01,487 --> 00:31:04,445
up to 5,000 dolphins in one group.
233
00:31:11,607 --> 00:31:15,236
This is fast becoming one of
the biggest groups of predators
234
00:31:15,327 --> 00:31:17,363
anywhere on the planet.
235
00:31:22,487 --> 00:31:25,399
The attackers spread out
into wide hunting lines,
236
00:31:25,487 --> 00:31:27,921
stretching up to a mile across.
237
00:31:37,967 --> 00:31:41,801
Other divisions follow on,
as ever tracking the dolphins.
238
00:31:50,527 --> 00:31:53,883
Shadowing them all, the Bryde's whale.
239
00:32:03,767 --> 00:32:06,042
They're all heading in one direction,
240
00:32:06,127 --> 00:32:09,278
towards a place
known as Waterfall Bluff.
241
00:32:16,287 --> 00:32:20,678
It's an arc in the coastline
which interrupts the flow of currents,
242
00:32:20,767 --> 00:32:23,440
trapping the water in a swirling eddy.
243
00:32:25,367 --> 00:32:28,200
And the dolphins know
that the massive shoals
244
00:32:28,287 --> 00:32:30,960
often get caught in this bottleneck.
245
00:32:41,087 --> 00:32:44,966
But these sardines
have managed to avoid the trap.
246
00:32:48,287 --> 00:32:52,280
The first shoals have been carried
well to the north of Waterfall Bluff,
247
00:32:52,367 --> 00:32:54,835
ahead of the dolphin super-pods.
248
00:33:02,647 --> 00:33:06,356
As the cool water is squeezed
into an ever thinner band
249
00:33:06,447 --> 00:33:07,800
closer to the shore,
250
00:33:07,887 --> 00:33:10,765
the shoals are forced up
into the shallows.
251
00:33:22,407 --> 00:33:27,117
Only now do we get a real sense
of the sheer volume of fish.
252
00:33:28,727 --> 00:33:33,357
This one shoal stretches
along the coast for 1 5 miles.
253
00:33:38,767 --> 00:33:41,042
The water is 1 5 metres deep
254
00:33:41,127 --> 00:33:44,039
and packed with sardines
from top to bottom.
255
00:33:47,047 --> 00:33:52,121
There could be more than 1 00 million
fish in this single shoal alone.
256
00:33:53,127 --> 00:33:55,846
As long as the sardines
are in such shallow water,
257
00:33:55,927 --> 00:33:57,838
they're beyond
the reach of the dolphins,
258
00:33:57,927 --> 00:34:00,885
who won't follow for fear of stranding.
259
00:34:02,367 --> 00:34:06,406
And the gannets can't risk diving
into such shallow water either.
260
00:34:10,767 --> 00:34:13,361
But there are hunters who can follow.
261
00:34:14,087 --> 00:34:16,840
And they've arrived in their thousands.
262
00:34:19,007 --> 00:34:20,360
Sharks.
263
00:34:38,327 --> 00:34:43,481
Dusky, copper and ragged-tooth sharks
encircle the sardines.
264
00:34:47,647 --> 00:34:51,959
But for the little fish,
there's safety in such vast numbers.
265
00:34:52,247 --> 00:34:56,445
The sheer volume of sardines,
the way they twist and turn in harmony,
266
00:34:56,527 --> 00:34:58,279
confuses the sharks.
267
00:35:05,127 --> 00:35:07,277
Without dolphins to round up the fish,
268
00:35:07,367 --> 00:35:10,439
these sharks have to
find their own solution.
269
00:35:22,407 --> 00:35:26,320
They try to trap the fish
against the water's surface.
270
00:35:31,767 --> 00:35:35,282
But this boiling water
is mostly sardines escaping.
271
00:35:35,367 --> 00:35:37,323
Few are actually eaten.
272
00:35:49,967 --> 00:35:53,676
Tiny fish triumph
over the marauding sharks.
273
00:36:05,407 --> 00:36:10,322
The sharks continue to harry the shoal,
pushing it ever northwards.
274
00:36:21,167 --> 00:36:24,079
Back at Waterfall Bluff,
the dolphins and gannets
275
00:36:24,167 --> 00:36:26,920
are waiting for the next
pulse of sardines
276
00:36:27,007 --> 00:36:29,362
to come up from the south.
277
00:36:29,967 --> 00:36:31,400
If there is another shoal,
278
00:36:31,487 --> 00:36:35,480
this kink in the coastline
is the perfect place to ambush them.
279
00:36:35,767 --> 00:36:37,598
But if the fish don't come,
280
00:36:37,687 --> 00:36:42,397
these hungry predators face a long
journey all the way back to the Cape.
281
00:36:48,007 --> 00:36:50,396
To the north,
the survivors of the shark attack
282
00:36:50,487 --> 00:36:54,366
are nearing the end of their run
at the beaches around Durban.
283
00:36:58,567 --> 00:37:01,127
These seem like the lucky ones.
284
00:37:01,207 --> 00:37:05,359
On their epic journey
they've evaded an army of hunters.
285
00:37:07,447 --> 00:37:11,520
But one final, unexpected
predator lies in wait.
286
00:37:24,287 --> 00:37:28,485
Fishermen can only net the sardines
once they've swum this far north,
287
00:37:28,567 --> 00:37:30,876
within easy reach of the shore.
288
00:37:34,127 --> 00:37:37,517
Last year no sardines
were seen on this coast.
289
00:37:37,727 --> 00:37:41,606
So far this winter, the fishermen
have landed only 50 tonnes,
290
00:37:41,687 --> 00:37:45,680
barely a tenth of what they'd expect
in a good year.
291
00:37:51,727 --> 00:37:55,276
That's how unpredictable
the Sardine Run has become.
292
00:38:08,727 --> 00:38:11,366
After such a long and hazardous voyage,
293
00:38:11,447 --> 00:38:14,803
it's a sad end for these sardines.
294
00:38:23,807 --> 00:38:29,006
At Waterfall Bluff, the dolphins
and gannets have had to bide their time.
295
00:38:33,927 --> 00:38:35,963
After missing the first shoal,
296
00:38:36,047 --> 00:38:38,163
these predators
are relying on the currents
297
00:38:38,247 --> 00:38:42,126
to sweep another big pulse of sardines
up the coast.
298
00:38:44,447 --> 00:38:47,678
Now another great shoal is on the way.
299
00:38:47,767 --> 00:38:50,918
And it's heading straight
for Waterfall Bluff.
300
00:38:58,007 --> 00:39:02,205
Trapped between the shore on one side
and the warm water on the other,
301
00:39:02,287 --> 00:39:05,563
these fish are swimming straight
towards the enemy.
302
00:39:18,327 --> 00:39:21,763
The sardines fall back
on their instinctive defence,
303
00:39:21,847 --> 00:39:25,920
swarming into a huge mass
that confuses a predator.
304
00:39:37,247 --> 00:39:41,399
But the dolphins have a strategy
that turns this to their advantage.
305
00:39:46,087 --> 00:39:49,966
Working together,
they separate off a pocket of sardines.
306
00:39:53,967 --> 00:39:59,087
In smaller numbers the fishes
shoaling defence now works against them.
307
00:40:00,407 --> 00:40:04,639
The dolphins corral the bait ball
and herd it to the surface.
308
00:40:18,567 --> 00:40:21,923
This is what the other hunters
have been waiting for.
309
00:40:24,367 --> 00:40:27,518
Now the sardines are within range
of the gannets.
310
00:40:49,367 --> 00:40:51,961
The bait balls form and reform,
311
00:40:52,047 --> 00:40:55,198
seldom lasting longer than
a few minutes each.
312
00:41:19,127 --> 00:41:23,484
The sharks pile in, taking advantage
of the dolphins' hard work.
313
00:41:31,207 --> 00:41:34,995
The predators ignore each other.
There's only one victim here -
314
00:41:35,087 --> 00:41:39,319
the millions of tasty little fish
they've been stalking for so long.
315
00:42:01,527 --> 00:42:03,643
Young gannets join the frenzy.
316
00:42:03,727 --> 00:42:07,845
In just six months they have become
superb aerial hunters.
317
00:42:17,047 --> 00:42:21,962
Time after time, the dolphins round up
another shoal for destruction.
318
00:42:46,767 --> 00:42:49,361
Frantically, the little fish
try to get away
319
00:42:49,447 --> 00:42:54,282
from the seething surface of the water
to dive beyond the range of the gannets.
320
00:42:58,447 --> 00:43:02,326
Now,
something truly astonishing happens.
321
00:43:04,647 --> 00:43:08,356
Diving takes the gannets
down to 1 0 metres.
322
00:43:09,967 --> 00:43:13,642
Then the aerial squadrons
become shoals of swimmers
323
00:43:13,727 --> 00:43:18,164
as they pursue the fish
down to 20 metres.
324
00:43:21,767 --> 00:43:24,406
Sardines join with their predators
325
00:43:24,487 --> 00:43:28,116
in a beautiful
yet macabre underwater ballet.
326
00:43:28,807 --> 00:43:32,004
There's little chance of escape
for these fish.
327
00:44:12,407 --> 00:44:16,241
The stage is set
for the biggest predator of all.
328
00:44:23,287 --> 00:44:28,600
The Bryde's whale takes in
1 0,000 fish in one giant mouthful.
329
00:44:33,007 --> 00:44:36,682
But this time around,
there are plenty of sardines for all.
330
00:44:46,047 --> 00:44:50,723
Each hunter amongst these millions
plays its part in the drama
331
00:44:50,807 --> 00:44:53,401
and each is dependent upon the other.
332
00:45:07,287 --> 00:45:09,960
The annual spectacle of the Sardine Run
333
00:45:10,047 --> 00:45:15,201
is undoubtedly the greatest gathering
of predators anywhere on the planet.
334
00:45:21,447 --> 00:45:25,406
It's surely
one of nature's great events.
335
00:46:15,887 --> 00:46:19,118
Then, almost as quickly as it began,
336
00:46:20,367 --> 00:46:21,880
it's over.
337
00:46:24,247 --> 00:46:26,636
As the brief winter comes to an end,
338
00:46:26,727 --> 00:46:31,801
warm currents flowing south
displace the corridor of cool water.
339
00:46:36,727 --> 00:46:38,399
Despite the massacre,
340
00:46:38,487 --> 00:46:43,003
more than half of all the sardines
swept up on the great run, survive.
341
00:46:47,287 --> 00:46:49,323
As the currents switch,
342
00:46:49,407 --> 00:46:52,285
the fortunate ones
make good their escape.
343
00:46:55,247 --> 00:46:58,239
From here,
they'll follow deep water currents,
344
00:46:58,327 --> 00:47:01,637
hitching a ride
back to the cool waters of the Cape.
345
00:47:07,447 --> 00:47:12,601
The Bryde's whale melts away
to resume its secretive life
346
00:47:12,687 --> 00:47:15,281
somewhere out in the big blue.
347
00:47:21,007 --> 00:47:26,240
The dolphin super-pods break up and
begin their long trek back to the Cape.
348
00:47:31,727 --> 00:47:34,321
Gannets, too, head south.
349
00:47:42,727 --> 00:47:46,037
As Waterfall Bluff
falls quiet once more,
350
00:47:46,127 --> 00:47:48,846
no one can say whether
this spectacular event
351
00:47:48,927 --> 00:47:51,646
will be repeated here in years to come.
352
00:48:00,687 --> 00:48:05,078
The Sardine Run may be unique
to the coast of South Africa,
353
00:48:05,167 --> 00:48:10,639
but it's a vivid reminder of the riches
that our oceans can still support.
31222
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