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The Great Barrier Reef.
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It's home to an extraordinarily
diverse community
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of animals and plants.
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'Here, unknown species
are still being found
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'and astonishing things discovered
about creatures we thought we knew.
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'In this series, our research vessel,
the Alucia,
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'will allow us to explore and
understand the reef as never before.
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'This marine paradise may be
best known
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'for its spectacular coral reefs...
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'..but it also has 300 sand islands.'
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600 continental islands.
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Miles of lush forest.
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And deep ocean channels.
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Each of these habitats attracts
a very different set of visitors.
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When I first came here
almost 60 years ago,
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we knew very little
about these communities.
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But today, new tracking systems
are allowing us
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to follow the lives of
these creatures in new ways.
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From the ocean's great predators...
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...to a mysterious whale
that seeks out human contact.
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I'll discover their surprising
reasons for visiting
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and reveal why the reef
is so important for their survival.
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Last time, we looked at the rich
community of animals
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that lives among the coral,
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but the reef also receives visitors.
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Some travel for thousands of miles
in order to get here
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and stay for only a few weeks.
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Others linger on the fringes
and come in every day.
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Each has its own particular reason
for doing so.
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The Great Barrier Reef consists
of 3,000 individual coral reefs.
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It stretches for 1,400 miles
along Australia's northeast coast.
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And every year, it attracts
over a million migrating animals.
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We're beginning our exploration
in the north,
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on the outskirts of
this vast wilderness.
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Our research vessel, the Alucia,
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has brought us out here
to Osprey Reef.
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90 miles, 150 kilometers
out in the Coral Sea
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from the edge of the Great Barrier.
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Isolated though it is, it nonetheless
plays a crucial part
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in the lives of many of the
inhabitants of the Barrier Reef.
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What makes Osprey so interesting
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is that it lies in the path of
the south equatorial current.
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This is a moving highway
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that sweeps a host of different
visitors towards the great reef.
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We are here to discover
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why this remote outpost
is so important to them.
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To do that, we're going to use
a very special piece of technology,
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the Alucia's Triton submarine.
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00:04:23,540 --> 00:04:27,260
It's the first submersible of its
kind ever to dive in these waters.
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Huh! It does look as though
water's gurgling up here,
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but in fact, my feet aren't wet.
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S-O, S-O, this is Nadir.
Am I clear to vent? Over.
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'Copy Nadir. So you are clear
to vent, clear to vent.
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'Have a good dive, guys.'
55
00:04:54,780 --> 00:04:56,180
Roger. Venting now.
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There we are!
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00:05:03,140 --> 00:05:08,419
'The sub not only gives us
stunning 360-degree views,
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00:05:08,420 --> 00:05:13,980
'it allows us to dive to depths where
no unprotected human has ever been.'
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For this dive, we are only
going down to about 35 metres,
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00:05:20,780 --> 00:05:22,619
just over 100 feet,
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where much of the wildlife
we're hoping to film will be feeding.
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Marine geologists have recently
gathered sufficient data
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for us to create an accurate
three-dimensional picture
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of Osprey Reef
for the very first time.
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00:05:43,220 --> 00:05:47,379
It is, in fact, a huge mountain
hidden beneath the waves
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and rising steeply from the seafloor
2,400 metres below.
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The top of this vast seamount
creates a shallow lagoon
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that supports a flourishing
community of corals.
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This wall of rock ahead of me
is the flank of Osprey Reef.
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00:06:11,740 --> 00:06:15,859
When cold, deep,
nutrient-rich currents from the ocean
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come in and strike it,
they defect it upwards.
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00:06:19,660 --> 00:06:24,380
And that creates an oasis
for living creatures of all kinds.
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Many creatures live here
throughout the year.
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And the boss of them all is one kind,
sharks.
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There's one! Close up.
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Whatever else you say about sharks,
they are so beautiful in the water.
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Resident predators mean one thing -
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a plentiful supply of food.
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For creatures traveling
vast distances to get to the reef,
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that makes Osprey a very desirable
waypoint on their journey.
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Seamounts are stopping-off points
for visitors.
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They come from far and wide.
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From tiger sharks to turtles.
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And they come to refuel and also,
it seems, recalibrate.
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It appears that this is a signpost
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and a checkpoint
on the way to the reef.
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Visitors arrive year round.
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Among them are hammerheads.
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00:07:56,180 --> 00:07:59,699
Like all sharks, they have tiny
sensors on their nose
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which can pick up signals
from the earth's magnetic field.
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And that helps them navigate through
the blue infinity of the open ocean.
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There are tiger sharks here, too.
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They come to the reef to feed.
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And they seem to know
exactly where they're going.
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The proportion of their brain
dedicated to smell
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is the largest of any shark.
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00:08:41,860 --> 00:08:43,899
Their two nostrils
work independently,
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allowing them to smell in stereo
and track prey over huge distances.
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From Osprey, some tiger sharks
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travel to a very specific destination
on the reef.
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230 miles north of Osprey
lies Raine Island.
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Every summer, the tiger sharks arrive
without fail.
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They're here to take advantage
of a major event on the reef -
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the arrival of the female
green turtles.
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The tiger sharks aren't here to kill,
they've come to scavenge on the dead.
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The unlucky turtles who have not
survived
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their exhausting immigration.
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This is why the tiger shark
has earned the unflattering title...
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...Dustbin of the Sea.
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They prefer the easy life
of the scavenger,
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so the majority of green turtles have
little to fear from these predators.
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In the summer months,
the turtles arrive in thousands.
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They have come from as far as
New Guinea, Vanuatu
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and New Caledonia to the east,
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as well as from the Torres Straits
and beyond to the west.
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Some have traveled an impressive
1,500 miles
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to reach this particular beach.
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It measures only a few hundred
metres across,
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a tiny speck in a vast ocean.
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But Raine Island plays a major role
in their lives.
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70% of the Barrier Reef's breeding
green turtles come here to lay.
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It's one of the most important
nesting sites in the world.
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I first visited Raine
for a television series
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called Zoo Quest back in 1957.
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At the time, Raine was little known
and rarely visited.
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It was then I met my first
green turtle hatchling.
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Back then, we had no idea
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just how extraordinary a story
these turtles had to tell.
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We now know that if they survive,
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they'll spend the next 40 years
of their lives at sea.
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Only then do they return to Raine
to breed.
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And astonishingly, they return
to exactly the same beach
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where they themselves hatched.
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How they find their way back
after decades at sea
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is one of the mysteries
that surround this species.
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00:12:07,100 --> 00:12:10,339
But new research is suggesting that,
just like the sharks,
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they navigate using
the earth's magnetic field.
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They weigh up to 130 kilos,
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so hauling themselves up the beach
is a grueling task.
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But it's expected that 30,000 of them
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will come ashore
to lay their eggs this year.
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With space in short supply,
it's every female for herself.
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Once they've dug a hole,
laying can begin.
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Each egg is roughly the size of
a Ping-Pong ball.
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A female may lay up to 120 of them
at a time
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and she's able to do this six times
in a single breeding season.
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Once the eggs are laid,
she buries them.
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For the next 60 days, the sand
will conceal them from predators
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and protect them
from the blistering sun.
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Keeping a very close eye
on the turtles' progress
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is Dr Andy Dunstan of the Great
Barrier Reef Marine Park Authority.
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Raine Island is the biggest
green turtle rookery in the world.
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So it's incredibly important
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with the state of green turtles
at the moment.
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Because of this, Raine is the most
protected island on the reef.
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Only a handful of biologists
are allowed to land here
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and Andy and his team have done so
for very good reason.
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A huge number of turtles
are certainly coming ashore
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to lay their eggs on the island,
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but the team's observations
have revealed a worrying trend.
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The number of young hatchlings
surviving incubation in the sand
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has dropped to just 20%.
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It's a serious cause for concern.
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The hatchlings we're seeing
coming out
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are nowhere near the numbers
that they should be.
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The nests, when we dig them up,
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have got really low levels
of successful eggs hatching.
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And that is happening
because of the very substance
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that makes this island so suitable
for nest-building in the first place.
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Raine Island's a sand island.
They move.
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But specifically
for the green turtles here,
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the nesting area has become lower,
so what we're seeing now
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that we never saw 30 years ago
is inundation of tidal waters.
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This means that at high tide, the
island is being flooded from below
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and the developing turtle eggs
are being drowned.
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75% of the beach-nesting area
is not suitable.
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Because turtles take a long time
to mature,
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we expect to see a crash in those
adult turtle numbers in the future.
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If we do something about hatchling
success and nesting success now,
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we should see that recover again.
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Last year, Andy and his team
made an ambitious plan.
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In a trial sector, they have raised
the turtles nesting area
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by one and a half metres.
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They hope this will keep
the developing eggs
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clear of the tidal waters
and out of harm's way.
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Two long months after
the egg laying began,
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the team returns to see if their plan
is working.
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Under the cover of darkness,
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the first of the evening's hatchlings
start to emerge.
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They started to push their way up
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through the sand
about two days earlier.
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Now comes the moment that Andy
and his team have been waiting for.
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A shallow trench helps to delay
the new arrivals temporarily
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and allow the team to count them.
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00:17:23,980 --> 00:17:26,619
So far, the signs
are very encouraging.
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And as the night wears on,
it gets better and better.
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00:17:32,260 --> 00:17:36,099
This is looking great. We're getting
much better nesting success,
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00:17:36,100 --> 00:17:38,339
much better hatching success,
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the turtles are nesting right across
the whole area
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and not disturbing each other
so much.
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And those clutches which are
underneath the sand
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are hatching much more successfully.
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It's confirmation that Andy and
his team have found the right way
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to restore this vital breeding area.
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But for the young hatchlings, the
trials of life have only just begun.
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Each new arrival will have to make
a perilous dash to reach the ocean.
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Now they're on their own.
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Andy and his team must not interfere
at this stage.
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00:18:22,780 --> 00:18:25,859
Inevitably, the tiny, defenseless
hatchlings
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attract scores of predators.
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00:18:27,900 --> 00:18:29,940
SQUAWKING
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Terns and herons patrol the beach.
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00:18:44,780 --> 00:18:47,940
And in the shallows,
reef sharks lie in wait.
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00:19:41,620 --> 00:19:43,659
Great numbers are lost,
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00:19:43,660 --> 00:19:48,340
but enough will make it to the ocean
to ensure the species' survival.
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00:19:59,300 --> 00:20:02,179
As the young turtles leave the reef,
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00:20:02,180 --> 00:20:06,219
they get a helping hand
from the ocean currents.
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00:20:06,220 --> 00:20:11,379
Swept out into the open ocean
and there, they face new hazards.
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If they survive,
they will eventually return
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00:20:14,740 --> 00:20:18,140
to the very same beaches
where they hatched.
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00:20:21,060 --> 00:20:24,499
Remote islands like Raine
are hugely important
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to both turtles and birds
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00:20:26,900 --> 00:20:29,180
that come to the reef
to lay their eggs.
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There are 900 isolated islands on the
Great Barrier from which to choose
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00:20:36,780 --> 00:20:39,740
and there's a habitat
to suit every visitor.
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00:20:42,620 --> 00:20:45,299
Turtles need sandy beaches
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00:20:45,300 --> 00:20:47,700
and many birds need trees.
228
00:20:50,620 --> 00:20:54,379
'The Alucia is taking us
to one of these wooded islands
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00:20:54,380 --> 00:20:56,820
'near the southern end
of the Great Barrier.'
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00:20:59,060 --> 00:21:03,059
Almost 1,000 miles south of Raine
is Heron Island.
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00:21:03,060 --> 00:21:04,739
And every year, it attracts
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00:21:04,740 --> 00:21:07,780
thousands of birds
seeking somewhere safe to nest.
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00:21:11,020 --> 00:21:14,499
The island is surrounded by
fragile coral reef.
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00:21:14,500 --> 00:21:18,860
So to reach the shore, I'm leaving
the Alucia anchored in deeper water.
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00:21:28,900 --> 00:21:30,380
FAINT BIRDSONG
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The warm waters of the Barrier Reef
are full of fish.
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Full of food, as far as
birds are concerned.
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There are immense numbers of seabirds
throughout the year on the reef.
239
00:21:49,100 --> 00:21:53,139
But the moment comes in the year
when, in fact, a bird has to lay.
240
00:21:53,140 --> 00:21:56,939
And to do that,
it has to go onto land.
241
00:21:56,940 --> 00:22:01,219
And the number of sites where they
can build a nest are very limited.
242
00:22:01,220 --> 00:22:04,979
So they will put up with a great deal
of crowding
243
00:22:04,980 --> 00:22:09,740
and even with intruders, like myself,
without deserting their nest.
244
00:22:13,380 --> 00:22:15,220
Hello.
245
00:22:16,620 --> 00:22:19,659
'Noddies are very protective parents.
246
00:22:19,660 --> 00:22:23,180
'Very little deters them
from their chick-rearing duties.'
247
00:22:29,820 --> 00:22:32,179
Over one-and-a-half million birds
248
00:22:32,180 --> 00:22:35,300
come to the Great Barrier's islands
every year to breed.
249
00:22:38,580 --> 00:22:42,460
To see one of the most intriguing,
you'll have to wait until after dark.
250
00:22:52,900 --> 00:22:54,380
WAILING
251
00:22:55,860 --> 00:22:59,659
'The first indication that this
secretive character has arrived
252
00:22:59,660 --> 00:23:02,299
'is its rather unusual song.'
253
00:23:02,300 --> 00:23:04,340
WAILING
254
00:23:09,860 --> 00:23:12,539
The old sailors used to call it
the ghost bird
255
00:23:12,540 --> 00:23:15,339
because of its extraordinary call.
256
00:23:15,340 --> 00:23:18,779
More properly known as
the wedge-tailed shearwater.
257
00:23:18,780 --> 00:23:20,860
WAILING
258
00:23:28,180 --> 00:23:33,019
'The birds' haunting calls guide me
to their breeding grounds.'
259
00:23:33,020 --> 00:23:35,420
WAILING
260
00:23:50,060 --> 00:23:54,619
These are true seafaring birds.
Out at sea when they're feeding,
261
00:23:54,620 --> 00:23:57,619
they are very expert at flying
just above the surface,
262
00:23:57,620 --> 00:24:00,819
or indeed swimming on the surface,
catching their fish.
263
00:24:00,820 --> 00:24:02,979
But when they come into land, well,
264
00:24:02,980 --> 00:24:05,699
they have to come in in the dark,
for a start.
265
00:24:05,700 --> 00:24:08,340
And their landing is sometimes
not very expert.
266
00:24:11,620 --> 00:24:13,659
Night-vision cameras probably give us
267
00:24:13,660 --> 00:24:17,300
better pictures of their landing
ground than they seem to have.
268
00:24:32,340 --> 00:24:35,579
Their legs with which they paddle
over the surface of the sea
269
00:24:35,580 --> 00:24:39,980
are placed far back on their body,
and that makes them clumsy walkers.
270
00:24:43,100 --> 00:24:45,019
These birds have traveled
271
00:24:45,020 --> 00:24:46,940
an extraordinary 4,000 miles
to get here.
272
00:24:51,340 --> 00:24:53,579
After spending months feeding at sea,
273
00:24:53,580 --> 00:24:55,500
they've had to come to land
in order to breed.
274
00:24:58,540 --> 00:25:00,659
Once paired, they're devoted couples
275
00:25:00,660 --> 00:25:03,820
and both male and female
share the tasks of parenthood.
276
00:25:08,900 --> 00:25:10,699
Even though there are trees here,
277
00:25:10,700 --> 00:25:13,940
the shearwaters prefer to make
their nests underground.
278
00:25:19,940 --> 00:25:23,499
At the bottom of the nest hole,
their three-week-old chick
279
00:25:23,500 --> 00:25:25,940
is waiting for its next meal.
280
00:25:29,100 --> 00:25:30,860
TWEETING
281
00:25:34,060 --> 00:25:36,700
Being a shearwater parent
is a demanding job.
282
00:25:39,300 --> 00:25:41,780
Their young requires
constant feeding.
283
00:25:43,220 --> 00:25:44,859
It consumes so much food
284
00:25:44,860 --> 00:25:48,500
that eventually, it'll outweigh
its own parents.
285
00:25:51,540 --> 00:25:56,219
But its demands compel the adults
to continually fly out to sea
286
00:25:56,220 --> 00:25:58,260
and come back again with more food.
287
00:26:00,300 --> 00:26:04,100
And their takeoffs are often
just as clumsy as their landings.
288
00:26:35,940 --> 00:26:38,299
Fortunately for their nestlings,
289
00:26:38,300 --> 00:26:40,900
there's no shortage of fish
in the summer months.
290
00:26:42,740 --> 00:26:46,220
And scientists have only just
discovered why that is.
291
00:26:53,260 --> 00:26:56,579
In the waters
just beyond Heron Island,
292
00:26:56,580 --> 00:27:00,820
there's a rich, swirling current
known as the Capricorn Eddy.
293
00:27:05,420 --> 00:27:09,739
As it spins clockwise,
it pulls up cool waters from below,
294
00:27:09,740 --> 00:27:14,539
which bring rich nutrients
to the surface.
295
00:27:14,540 --> 00:27:20,059
That fuels the growth of huge blooms
of tiny marine creatures, plankton,
296
00:27:20,060 --> 00:27:22,860
the foundation of the entire
marine food web.
297
00:27:24,780 --> 00:27:28,819
So this part of the reef
is particularly rich with fish.
298
00:27:28,820 --> 00:27:31,460
Vital food for the hungry young.
299
00:27:36,380 --> 00:27:39,219
By choosing Heron Island
as a nesting ground,
300
00:27:39,220 --> 00:27:42,860
the birds can give their nestlings
the best possible start in life.
301
00:27:48,820 --> 00:27:51,379
When I first came to
the Barrier Reef,
302
00:27:51,380 --> 00:27:54,220
we knew very little about
these seasonal visitors.
303
00:27:55,940 --> 00:27:58,899
We could only speculate
as to why they came here
304
00:27:58,900 --> 00:28:00,940
and where they came from.
305
00:28:03,580 --> 00:28:07,299
Today, new research is enabling us
to understand more clearly
306
00:28:07,300 --> 00:28:12,700
why, every year, particular species
come to specific locations to breed.
307
00:28:14,860 --> 00:28:16,779
But there are still large animals
308
00:28:16,780 --> 00:28:20,859
whose movements remain
something of a mystery.
309
00:28:20,860 --> 00:28:24,299
Manta rays are the nomads
of the reef.
310
00:28:24,300 --> 00:28:26,539
They're huge creatures.
311
00:28:26,540 --> 00:28:30,139
They can measure 15 feet,
five metres across
312
00:28:30,140 --> 00:28:33,659
and weigh almost
one-and-a-half tonnes.
313
00:28:33,660 --> 00:28:36,779
They come to the reef to feed on
plankton,
314
00:28:36,780 --> 00:28:39,299
but they also use it as a sanctuary,
315
00:28:39,300 --> 00:28:42,380
where they can breed,
or get a good clean.
316
00:28:46,100 --> 00:28:50,379
Many make their way to the waters
that surround Lady Elliot Island
317
00:28:50,380 --> 00:28:52,740
on the southern end
of the Great Barrier.
318
00:28:57,100 --> 00:29:00,659
For the visiting manta rays,
this is a paradise.
319
00:29:00,660 --> 00:29:03,940
A place where these ocean giants
can get a little pampering.
320
00:29:12,180 --> 00:29:15,099
These are the beauty salons
of the reef.
321
00:29:15,100 --> 00:29:18,019
And they're often run
by a pair of wrasse,
322
00:29:18,020 --> 00:29:21,020
small fish with a stripe
running from head to tail.
323
00:29:26,660 --> 00:29:28,099
These committed cleaners
324
00:29:28,100 --> 00:29:30,900
regularly tend to a host of
different creatures.
325
00:29:35,380 --> 00:29:37,219
They provide a vital service,
326
00:29:37,220 --> 00:29:41,259
removing the dead skin and parasites
from outside
327
00:29:41,260 --> 00:29:44,100
and even inside
their clients' bodies.
328
00:29:47,740 --> 00:29:49,819
It may seem like a thankless task,
329
00:29:49,820 --> 00:29:52,860
but the cleaner fish
are getting a good meal out of it.
330
00:29:57,340 --> 00:30:01,020
And of all their clients, the
manta rays are their star customers.
331
00:30:08,100 --> 00:30:10,940
When business is brisk,
they patiently wait in line.
332
00:30:17,820 --> 00:30:19,699
Like planes in a holding pattern,
333
00:30:19,700 --> 00:30:22,700
they circle
until an opportunity arrives.
334
00:30:31,820 --> 00:30:35,900
When it's their turn, the manta rays
surrender themselves completely.
335
00:30:38,980 --> 00:30:42,020
Within seconds,
a host of fish rush to their side.
336
00:30:43,620 --> 00:30:46,700
Manta rays are rarely left waiting
for long.
337
00:30:55,220 --> 00:30:59,300
Each fish tends to a very specific
part of the manta's body.
338
00:31:00,860 --> 00:31:03,340
And the cleaning can last
a full hour.
339
00:31:08,780 --> 00:31:11,899
For the most part,
the service is second to none.
340
00:31:11,900 --> 00:31:15,340
But occasionally, the cleaners
can get a little carried away.
341
00:31:21,700 --> 00:31:25,460
A female wrasse has taken a nibble
out of the manta ray's flesh.
342
00:31:26,740 --> 00:31:30,619
She's broken the rules,
and there's a price pay.
343
00:31:30,620 --> 00:31:33,459
Her partner chases after her.
344
00:31:33,460 --> 00:31:36,540
It's the cleaner fish equivalent
of a stern telling off.
345
00:31:39,700 --> 00:31:43,380
Scientists believe males do this
to protect future business.
346
00:31:45,780 --> 00:31:49,419
If the bite is a one-off,
the manta ray will return.
347
00:31:49,420 --> 00:31:52,659
But research has shown
that if it happens too often,
348
00:31:52,660 --> 00:31:56,140
the pair risks driving
regular visitors away.
349
00:32:01,060 --> 00:32:03,299
Fortunately,
it seems her indiscretion
350
00:32:03,300 --> 00:32:05,499
hasn't put their client off.
351
00:32:05,500 --> 00:32:09,340
The manta is back
and business has resumed.
352
00:32:13,380 --> 00:32:16,059
Manta rays come here in such numbers
353
00:32:16,060 --> 00:32:20,140
that the island has become the
focal point for a research project.
354
00:32:26,100 --> 00:32:29,499
Dr Kathy Townsend has been tracking
the manta's movements
355
00:32:29,500 --> 00:32:31,900
and numbers for the last seven years.
356
00:32:42,500 --> 00:32:45,379
Lady Elliot Island
is like the center of the universe
357
00:32:45,380 --> 00:32:48,659
for manta rays on
the east coast of Australia.
358
00:32:48,660 --> 00:32:50,459
We come back time and time again
359
00:32:50,460 --> 00:32:53,660
because we get large aggregations
of these animals.
360
00:32:54,900 --> 00:32:57,179
We are doing several things
with the manta rays.
361
00:32:57,180 --> 00:32:59,099
First of all, we're trying
to understand
362
00:32:59,100 --> 00:33:00,939
how many there are potentially here.
363
00:33:00,940 --> 00:33:03,700
And to do that, you need to do
some sort of tagging.
364
00:33:06,020 --> 00:33:10,499
This is a key part of Kathy's work in
tracking these gentle ocean giants.
365
00:33:10,500 --> 00:33:13,779
And the team has already attached
acoustic tags
366
00:33:13,780 --> 00:33:17,299
to a large number of study animals.
367
00:33:17,300 --> 00:33:21,459
We have six acoustic listening
stations around Lady Elliot Island.
368
00:33:21,460 --> 00:33:23,299
And as an animal goes past,
369
00:33:23,300 --> 00:33:26,779
within a 500-meter radius
of this listening station,
370
00:33:26,780 --> 00:33:30,140
it picks up the tag and we know
that that animal's been past.
371
00:33:33,900 --> 00:33:36,899
That has revealed that many
of the mantas have traveled
372
00:33:36,900 --> 00:33:40,340
hundreds of miles up the eastern
coast of Australia to get here.
373
00:33:44,340 --> 00:33:46,659
One of the lovely things
about working with manta rays
374
00:33:46,660 --> 00:33:48,459
is that they're extremely curious
375
00:33:48,460 --> 00:33:51,540
and they'll seek you out to come
and see what you're up to.
376
00:34:06,140 --> 00:34:08,179
It's really unusual behaviour.
377
00:34:08,180 --> 00:34:10,059
Most sharks and rays
have no interest
378
00:34:10,060 --> 00:34:12,859
in having any interaction
with people whatsoever.
379
00:34:12,860 --> 00:34:16,819
But for whatever reason, manta rays
are highly-curious creatures
380
00:34:16,820 --> 00:34:19,060
and will basically look at you
eye to eye.
381
00:34:21,620 --> 00:34:25,939
The manta ray's inquisitive nature
works to Kathy's advantage.
382
00:34:25,940 --> 00:34:30,140
It means she can get close enough to
photograph them for identification.
383
00:34:31,980 --> 00:34:35,860
And one of the best places to do that
is at the cleaning stations.
384
00:34:48,460 --> 00:34:50,499
We need to get in underneath
the animal
385
00:34:50,500 --> 00:34:53,059
and take a photograph from below.
386
00:34:53,060 --> 00:34:57,099
Each individual has a very unique
spot pattern
387
00:34:57,100 --> 00:35:00,819
that stays with them from birth
until they pass away.
388
00:35:00,820 --> 00:35:02,420
That's very handy for us.
389
00:35:07,700 --> 00:35:10,419
When Project Manta began
seven years ago,
390
00:35:10,420 --> 00:35:14,979
it was thought that fewer than
40 individuals came to Lady Elliot.
391
00:35:14,980 --> 00:35:19,060
Today, Kathy and her team
have catalogued more than 800.
392
00:35:22,540 --> 00:35:25,139
I think manta ray research is quite
important
393
00:35:25,140 --> 00:35:28,099
because first of all,
this is a very large-bodied animal
394
00:35:28,100 --> 00:35:31,259
that very little information
is known about.
395
00:35:31,260 --> 00:35:33,099
Various places around the world,
396
00:35:33,100 --> 00:35:36,019
the manta ray populations
have declined dramatically,
397
00:35:36,020 --> 00:35:39,699
to the point where they've now been
listed as threatened
398
00:35:39,700 --> 00:35:41,820
on that list for endangered species.
399
00:35:44,260 --> 00:35:48,340
For the visiting mantas, the Great
Barrier Reef really is a sanctuary.
400
00:35:50,380 --> 00:35:53,220
Here, this ocean giant
is properly protected.
401
00:35:55,220 --> 00:35:56,459
While they're in these waters,
402
00:35:56,460 --> 00:36:00,100
they're safe from the fisheries
that threaten them elsewhere.
403
00:36:03,980 --> 00:36:07,220
Manta rays aren't the only animals
that find refuge here.
404
00:36:08,820 --> 00:36:12,420
The Great Barrier protects
its visitors in many different ways.
405
00:36:19,140 --> 00:36:23,460
'That becomes clear when you
look at the reef from above.
406
00:36:26,700 --> 00:36:28,779
'This part of tropical Australia
407
00:36:28,780 --> 00:36:32,619
'lies right in the path of regular
seasonal cyclones.
408
00:36:32,620 --> 00:36:35,779
'And from up here, you can see
what valuable protection
409
00:36:35,780 --> 00:36:37,500
'the reef can provide.'
410
00:36:39,820 --> 00:36:41,939
This tangle of limestone walls
411
00:36:41,940 --> 00:36:45,979
acts as a barrier
against the open ocean.
412
00:36:45,980 --> 00:36:50,459
Between it and the land,
the waters are warm and shallow.
413
00:36:50,460 --> 00:36:53,420
An ideal haven for visitors.
414
00:36:55,460 --> 00:36:58,219
In the winter, many creatures
come up here to escape
415
00:36:58,220 --> 00:37:00,820
the freezing temperatures
of the Antarctic.
416
00:37:08,220 --> 00:37:11,500
Among them are humpback whales.
417
00:37:31,820 --> 00:37:33,259
WHALE SONG
418
00:37:33,260 --> 00:37:35,059
Weighing up to 40 tonnes,
419
00:37:35,060 --> 00:37:38,179
they're the largest of
the Great Barrier Reef's visitors
420
00:37:38,180 --> 00:37:41,300
and they have also traveled
great distances to get here.
421
00:37:51,540 --> 00:37:55,939
Each year, they make an exhausting
6,000-mile-round trip
422
00:37:55,940 --> 00:37:58,340
from the Antarctic and back again.
423
00:38:03,180 --> 00:38:05,660
Incredibly, 20,000 of them do it.
424
00:38:12,460 --> 00:38:14,779
Here, in these warm
and sheltered waters,
425
00:38:14,780 --> 00:38:17,540
they give birth
and suckle their newborn calves.
426
00:38:22,860 --> 00:38:25,139
But in fact, we still know
very little
427
00:38:25,140 --> 00:38:27,460
about what else they do
once they get here.
428
00:38:32,300 --> 00:38:35,300
Where exactly do they go
during their time on the reef?
429
00:38:39,500 --> 00:38:41,019
The fact that we don't know
430
00:38:41,020 --> 00:38:44,500
is a reminder of just how vast
this great wilderness is.
431
00:38:47,980 --> 00:38:51,140
But not all whales make
the task of tracking them so hard.
432
00:38:54,180 --> 00:38:57,459
In fact, there's one species which
does quite the opposite.
433
00:38:57,460 --> 00:39:01,299
Incredibly, this whale actively
seeks out the scientists
434
00:39:01,300 --> 00:39:03,500
who are trying to study them.
435
00:39:14,180 --> 00:39:18,940
This endearing little character
is the dwarf minke whale.
436
00:39:21,620 --> 00:39:24,059
And surprisingly,
it was only first observed
437
00:39:24,060 --> 00:39:26,260
here on the reef in the 1980s.
438
00:39:29,700 --> 00:39:33,979
But since then, we've realised that
they're extremely faithful visitors,
439
00:39:33,980 --> 00:39:37,660
returning every year to the
same location on the northern reef.
440
00:39:46,180 --> 00:39:48,980
Why they do so,
we still don't understand.
441
00:39:51,660 --> 00:39:54,340
But research is beginning
to reveal their story.
442
00:39:56,940 --> 00:39:59,779
Dr Alistair Birtles knows more about
443
00:39:59,780 --> 00:40:03,459
this still-mysterious species
than anyone else.
444
00:40:03,460 --> 00:40:06,820
So he's affectionately known as
Professor Minke.
445
00:40:09,580 --> 00:40:14,020
To observe the whales in detail,
he has to step into their world.
446
00:40:16,260 --> 00:40:19,259
The very first time I got in
the water, um...
447
00:40:19,260 --> 00:40:25,419
was with a degree of apprehension,
great excitement.
448
00:40:25,420 --> 00:40:29,459
Um... I don't think I'd ever been
in the water with a whale before.
449
00:40:29,460 --> 00:40:33,779
And the first thing you see
is the white shoulder, um...
450
00:40:33,780 --> 00:40:37,939
and then the rest of the Grey animal
emerges around it.
451
00:40:37,940 --> 00:40:41,179
It's very special being in the water
452
00:40:41,180 --> 00:40:44,059
with these animals
in their own environment.
453
00:40:44,060 --> 00:40:46,940
It's an extraordinary experience.
454
00:40:50,380 --> 00:40:53,019
Every year, Alistair
and his research team
455
00:40:53,020 --> 00:40:55,740
return to spend time with
the dwarf minkes.
456
00:40:58,300 --> 00:41:02,339
These annual reunions are beginning
to reveal more and more
457
00:41:02,340 --> 00:41:04,380
about these fascinating creatures.
458
00:41:07,060 --> 00:41:11,139
It seems that they spend most of
their lives out in the open ocean,
459
00:41:11,140 --> 00:41:13,940
leading what's thought to be
a solitary existence.
460
00:41:17,020 --> 00:41:20,539
But surprisingly, when they get here,
on the Great Reef,
461
00:41:20,540 --> 00:41:22,660
they actively seek human contact.
462
00:41:26,980 --> 00:41:29,380
Behaviour like this
happens nowhere else.
463
00:41:31,340 --> 00:41:34,619
It is entirely the world's curiosity
that brings them in.
464
00:41:34,620 --> 00:41:37,699
I think we're a rather
strange object.
465
00:41:37,700 --> 00:41:40,499
We're a visitor into their world.
466
00:41:40,500 --> 00:41:44,299
I'm sure they're wondering exactly
what we are
467
00:41:44,300 --> 00:41:47,860
and what we're doing, just as
we're wondering what they're doing.
468
00:41:50,580 --> 00:41:53,739
For Birtles, there are
many familiar faces here.
469
00:41:53,740 --> 00:41:56,780
And he has his own pet names
for regular visitors.
470
00:41:59,060 --> 00:42:03,300
Bento, I have seen every year
for the last eight years.
471
00:42:04,700 --> 00:42:06,539
She has a bent-over dorsal fin
472
00:42:06,540 --> 00:42:11,299
from I think where she was
fairly savagely mauled by a shark.
473
00:42:11,300 --> 00:42:14,339
And last year's encounter
was a particularly special one
474
00:42:14,340 --> 00:42:16,579
because she had a calf with her.
475
00:42:16,580 --> 00:42:20,579
That's the first time in eight years
that we've known she had a calf.
476
00:42:20,580 --> 00:42:24,820
And it was a little male and it was
a very special interaction.
477
00:42:33,580 --> 00:42:36,379
What Birtles and his team
want to discover
478
00:42:36,380 --> 00:42:38,659
is why this usually-solitary whale
479
00:42:38,660 --> 00:42:42,140
suddenly becomes so extremely
social when it gets here.
480
00:42:43,940 --> 00:42:46,179
There are a number of clues.
481
00:42:46,180 --> 00:42:50,019
We know they're not feeding.
We've never seen them feed.
482
00:42:50,020 --> 00:42:52,620
But we see a lot of socializing
going on.
483
00:42:54,020 --> 00:42:57,539
Minkes were known as the silent
whale when we began working on them
484
00:42:57,540 --> 00:43:00,060
and there were no recordings
of dwarf minkes.
485
00:43:01,780 --> 00:43:05,660
It went on for quite a while
before we heard any sounds.
486
00:43:12,460 --> 00:43:14,779
And then there's an extraordinary
sound they make
487
00:43:14,780 --> 00:43:18,019
which the researcher who labelled it
488
00:43:18,020 --> 00:43:21,099
called it the Star Wars sound.
489
00:43:21,100 --> 00:43:24,299
I thought it was a little more like
Beethoven's Fifth
490
00:43:24,300 --> 00:43:28,619
because it's got a triple beat
and then a long shwang
491
00:43:28,620 --> 00:43:30,539
that he thought was the lightsaber.
492
00:43:30,540 --> 00:43:32,940
So it goes, da-da-da-dang.
493
00:43:34,100 --> 00:43:36,020
WHALE SONG
494
00:43:37,340 --> 00:43:38,779
WHALE SONG
495
00:43:38,780 --> 00:43:42,859
When you hear it underwater, it kind
of reverberates through your chest.
496
00:43:42,860 --> 00:43:44,859
It's a very powerful sound.
497
00:43:44,860 --> 00:43:46,900
WHALE SONG
498
00:43:50,340 --> 00:43:52,979
The song is only produced by males
499
00:43:52,980 --> 00:43:55,819
and it's thought to be related to
courtship.
500
00:43:55,820 --> 00:43:57,939
WHALE SONG
501
00:43:57,940 --> 00:44:00,899
Curiously, two thirds of
the individuals.
502
00:44:00,900 --> 00:44:03,500
Alistair encounters are adolescents.
503
00:44:05,180 --> 00:44:09,739
One theory is that the whales are
coming here to find potential mates
504
00:44:09,740 --> 00:44:13,100
and learn the dos and don'ts
of minke social behaviour.
505
00:44:15,340 --> 00:44:17,219
Though Birtles' team has amassed
506
00:44:17,220 --> 00:44:19,379
a huge amount of data
over the decades,
507
00:44:19,380 --> 00:44:22,420
there is clearly still much to learn.
508
00:44:23,860 --> 00:44:28,540
Where, for example, do the whales go
after this social gathering?
509
00:44:31,700 --> 00:44:34,219
But now, a brand-new
tagging programme
510
00:44:34,220 --> 00:44:36,900
is shedding more light
on their annual journey.
511
00:44:40,660 --> 00:44:43,380
Tagging is not easy.
512
00:44:46,620 --> 00:44:48,659
The diver has to get into position,
513
00:44:48,660 --> 00:44:51,699
choose his mark
and then discharge the tag,
514
00:44:51,700 --> 00:44:53,780
all on a single breath.
515
00:44:56,780 --> 00:44:58,980
There's no room for error.
516
00:45:20,940 --> 00:45:22,579
After initially taking fright,
517
00:45:22,580 --> 00:45:25,859
the whale comes back
to the dive boat.
518
00:45:25,860 --> 00:45:29,060
It seems that minkes aren't
too distressed by the process.
519
00:45:33,340 --> 00:45:35,979
The tracking data the team is now
collecting
520
00:45:35,980 --> 00:45:40,019
may reveal the piece of the puzzle
that, until now, has been missing.
521
00:45:40,020 --> 00:45:43,699
So for 20 years, we've been
studying what the whales do
522
00:45:43,700 --> 00:45:46,139
in this area of the Great Barrier
Reef.
523
00:45:46,140 --> 00:45:48,979
We know they're only here
for a few weeks
524
00:45:48,980 --> 00:45:51,019
and we had no idea where they went
525
00:45:51,020 --> 00:45:53,259
when they left
the Great Barrier Reef
526
00:45:53,260 --> 00:45:55,260
at the end of their sojourn here.
527
00:45:57,340 --> 00:45:59,339
It really is an extraordinary
journey
528
00:45:59,340 --> 00:46:01,579
that we now know that they make.
529
00:46:01,580 --> 00:46:05,179
Spot, the young male that was
the first ever minke
530
00:46:05,180 --> 00:46:09,739
to have a satellite tag attached
in 2013,
531
00:46:09,740 --> 00:46:15,619
he traveled over 7,000 kilometers
deep into the Subantarctic.
532
00:46:15,620 --> 00:46:21,099
That's an extraordinary journey
for what is a little whale, to make.
533
00:46:21,100 --> 00:46:25,019
The tagging tells us where
the whales are traveling fast
534
00:46:25,020 --> 00:46:27,939
and where they're spending
extra time.
535
00:46:27,940 --> 00:46:31,539
There's a few places along the east
coast of Australia and Bass Strait
536
00:46:31,540 --> 00:46:35,499
where they may spend one,
two or even three weeks of time
537
00:46:35,500 --> 00:46:38,699
milling around, probably feeding.
538
00:46:38,700 --> 00:46:42,459
So we may have discovered
some of these feeding sites
539
00:46:42,460 --> 00:46:45,620
for the dwarf minke whale
along their migration path.
540
00:46:47,460 --> 00:46:49,139
For Birtles, it's not just about
541
00:46:49,140 --> 00:46:52,019
solving the mystery
of where the whales go.
542
00:46:52,020 --> 00:46:55,499
I am worried about them
when they leave the reef.
543
00:46:55,500 --> 00:46:57,819
The dwarf minkes are well protected
544
00:46:57,820 --> 00:46:59,739
when they're in
the Great Barrier Reef,
545
00:46:59,740 --> 00:47:05,139
but when they leave there,
they face many threats and dangers
546
00:47:05,140 --> 00:47:08,819
and they have to cross
major shipping channels.
547
00:47:08,820 --> 00:47:12,739
There are all sorts of threats
from fishing.
548
00:47:12,740 --> 00:47:17,579
I mean, if commercial whaling
is resumed in the Southern Ocean,
549
00:47:17,580 --> 00:47:21,299
which is the objective
of the research that's going on
550
00:47:21,300 --> 00:47:25,260
at the moment from the Japanese,
then these whales would be at risk.
551
00:47:30,420 --> 00:47:33,979
It's hoped the new tagging programme
may help us understand
552
00:47:33,980 --> 00:47:38,060
how best to protect these whales
throughout the entire year.
553
00:47:40,900 --> 00:47:44,979
By venturing into their underwater
world, Birtles and his team
554
00:47:44,980 --> 00:47:48,220
are discovering valuable
new facts about these whales.
555
00:47:49,820 --> 00:47:52,220
But their research
has only just begun.
556
00:47:56,380 --> 00:48:00,419
The more we learn about the creatures
that come here, the more we discover
557
00:48:00,420 --> 00:48:03,860
just how important the Great Barrier
Reef is to their survival.
558
00:48:07,100 --> 00:48:08,820
The reef is immense.
559
00:48:10,260 --> 00:48:14,379
Millions of visitors travel
great distances to get to it.
560
00:48:14,380 --> 00:48:18,700
And there, find food, shelter
and an opportunity to meet a mate.
561
00:48:21,940 --> 00:48:25,780
A global community of animals
rely on this great wilderness.
562
00:48:28,460 --> 00:48:30,899
And that makes it one of
the most important
563
00:48:30,900 --> 00:48:33,180
and influential habitats
on the planet.
564
00:48:38,020 --> 00:48:41,020
Next time, in our final programme...
565
00:48:42,380 --> 00:48:46,139
...we'll investigate the dangers
that now threaten the reef
566
00:48:46,140 --> 00:48:47,540
and its inhabitants.
567
00:48:51,580 --> 00:48:53,419
THUNDERCLAP
568
00:48:53,420 --> 00:48:55,499
We'll meet the extraordinary people
569
00:48:55,500 --> 00:48:57,619
who are doing everything
in their power
570
00:48:57,620 --> 00:48:59,939
to protect this marine paradise.
571
00:48:59,940 --> 00:49:03,979
It is one of the most magnificent
ecosystems on the planet.
572
00:49:03,980 --> 00:49:06,259
What's really quite shocking is
that we may lose it
573
00:49:06,260 --> 00:49:09,139
before we truly understand it.
574
00:49:09,140 --> 00:49:12,499
And we'll attempt
our most ambitious dive yet.
575
00:49:12,500 --> 00:49:17,460
Nobody has ever dived as deep as this
before on the Great Barrier Reef.
576
00:49:19,620 --> 00:49:24,299
As we search for new species and
try to predict what the future holds
577
00:49:24,300 --> 00:49:26,740
for the Great Barrier.
578
00:49:44,820 --> 00:49:47,459
For this episode, one of
our underwater teams
579
00:49:47,460 --> 00:49:50,100
traveled to Lady Elliot Island
in the south.
580
00:49:54,820 --> 00:49:57,379
Here, the reef's majestic manta rays
581
00:49:57,380 --> 00:50:01,660
are stripped of dead skin
and parasites by tiny cleaner fish.
582
00:50:04,260 --> 00:50:06,940
The crew's goal was to film
a rare behaviour.
583
00:50:08,580 --> 00:50:11,659
The moment when the cleaner fish
breaks the rules
584
00:50:11,660 --> 00:50:14,420
and bites a manta ray's flesh.
585
00:50:16,060 --> 00:50:18,419
To film the story,
the team worked closely
586
00:50:18,420 --> 00:50:20,860
with marine biologist,
Dr Kathy Townsend.
587
00:50:24,300 --> 00:50:28,659
Manta rays will often seek out
and spend time with divers,
588
00:50:28,660 --> 00:50:32,420
which, of course, makes them amazing
animals to be in the water with.
589
00:50:33,780 --> 00:50:37,499
Manta rays may be inquisitive,
but they can easily be spooked.
590
00:50:37,500 --> 00:50:40,459
The challenge for cameraman,
Mike Pitts,
591
00:50:40,460 --> 00:50:43,300
was to make himself
as unobtrusive as possible.
592
00:50:45,500 --> 00:50:47,459
You are bulky and clumsy,
593
00:50:47,460 --> 00:50:49,619
you've got large cameras, lights.
594
00:50:49,620 --> 00:50:54,699
So what you don't want to do
is to obstruct the manta ray.
595
00:50:54,700 --> 00:50:58,339
The manta ray might get disturbed
and it'll just swim off.
596
00:50:58,340 --> 00:51:00,579
I generally keep as low as possible.
597
00:51:00,580 --> 00:51:03,419
So your profile sort of matches in
with the reef.
598
00:51:03,420 --> 00:51:05,499
And so what you notice
after a while is
599
00:51:05,500 --> 00:51:08,899
the manta rays will come closer
and closer and closer to you.
600
00:51:08,900 --> 00:51:13,819
And I can literally... I feel them
brushing over my head as they go.
601
00:51:13,820 --> 00:51:16,659
While the team's objective
was to film the cleaning station,
602
00:51:16,660 --> 00:51:18,459
on the fourth day of the shoot,
603
00:51:18,460 --> 00:51:21,300
they were treated to something
truly unexpected.
604
00:51:24,300 --> 00:51:26,299
We were close to the end of the dive
605
00:51:26,300 --> 00:51:29,019
and we hadn't really seen anything
for about 58 minutes
606
00:51:29,020 --> 00:51:31,020
and then I spotted a pair.
607
00:51:34,220 --> 00:51:37,979
I saw Kathy and suddenly
she zoomed off and we followed.
608
00:51:37,980 --> 00:51:41,619
And I could see out in the distance,
there was a male above a female
609
00:51:41,620 --> 00:51:44,979
and he was following her every move
610
00:51:44,980 --> 00:51:47,099
as she moved through the water.
611
00:51:47,100 --> 00:51:48,700
Kathy got really excited.
612
00:51:51,180 --> 00:51:53,659
They were undergoing behaviour
I'd never seen before.
613
00:51:53,660 --> 00:51:55,819
I'd seen various types of courtship
behaviour
614
00:51:55,820 --> 00:51:58,019
that involves having trains,
615
00:51:58,020 --> 00:52:01,299
where there's a female at the front
followed by several males.
616
00:52:01,300 --> 00:52:05,179
What was happening between these two
was really quite unique.
617
00:52:05,180 --> 00:52:08,419
The male was obviously trying
to court her,
618
00:52:08,420 --> 00:52:10,939
but in a very unusual way.
619
00:52:10,940 --> 00:52:12,939
He was taking his front
cephalic lobes
620
00:52:12,940 --> 00:52:15,420
and he was actually stroking her
on her back.
621
00:52:17,540 --> 00:52:19,779
Obviously trying to entice her
to say,
622
00:52:19,780 --> 00:52:22,020
"Listen, you know,
I'm the one for you".
623
00:52:23,260 --> 00:52:26,099
She, on the other hand,
was not quite enthusiastic
624
00:52:26,100 --> 00:52:29,540
about the attention
that he was bestowing upon her.
625
00:52:30,780 --> 00:52:33,619
And all of sudden, she'd just fling
up into the air to shake him off
626
00:52:33,620 --> 00:52:35,659
and say, "No, it's not ready
for that yet".
627
00:52:35,660 --> 00:52:37,660
And then she would settle back down.
628
00:52:46,340 --> 00:52:48,859
I knew it was something very special
because,
629
00:52:48,860 --> 00:52:51,899
seeing Kathy's reactions
to what was going on,
630
00:52:51,900 --> 00:52:55,140
she was so excited about it,
she was bubbling.
631
00:52:57,740 --> 00:53:00,019
You could wait a lifetime
to see something like that.
632
00:53:00,020 --> 00:53:01,860
Just a very rare event.
633
00:53:04,420 --> 00:53:07,739
In the far north, another wildlife
crew had their sights set
634
00:53:07,740 --> 00:53:11,539
on filming a very special
seasonal visitor.
635
00:53:11,540 --> 00:53:15,099
In winter, dwarf minke whales
come to the reef
636
00:53:15,100 --> 00:53:17,500
for just a few short weeks.
637
00:53:19,100 --> 00:53:21,139
Wildlife cameraman, Dean Miller,
638
00:53:21,140 --> 00:53:24,100
has been documenting these whales
for 15 years.
639
00:53:26,220 --> 00:53:28,619
It's a little bit unnerving
sometimes jumping in
640
00:53:28,620 --> 00:53:32,059
and seeing a seven-tonne,
seven-meter animal
641
00:53:32,060 --> 00:53:34,019
come out from the gloom.
642
00:53:34,020 --> 00:53:36,779
And you're hoping that it is going
to be the whale
643
00:53:36,780 --> 00:53:38,980
and not something
with a few more teeth.
644
00:53:40,260 --> 00:53:42,459
Every animal presents
a very different challenge
645
00:53:42,460 --> 00:53:44,499
when it comes to filming behaviour,
646
00:53:44,500 --> 00:53:48,260
but over the years, Dean has learned
the minke tricks of the trade.
647
00:53:51,020 --> 00:53:53,859
It's sometimes a game of
cat and mouse, in a way.
648
00:53:53,860 --> 00:53:56,499
Because if you're not looking,
they tend to come a lot closer.
649
00:53:56,500 --> 00:53:59,339
So if I can see a whale approaching
in the distance
650
00:53:59,340 --> 00:54:02,059
and I know it's going to be
a good approach this time,
651
00:54:02,060 --> 00:54:04,219
I'll purposely hold off
and turn my dome around
652
00:54:04,220 --> 00:54:07,259
and actually see in the reflection
of the dome the whale coming to me
653
00:54:07,260 --> 00:54:10,539
and then, when I think it's probably
about five to six metres away,
654
00:54:10,540 --> 00:54:13,339
I'll turn around and get
the best shot I've had all day.
655
00:54:13,340 --> 00:54:15,180
They sneak up on you.
656
00:54:16,780 --> 00:54:18,859
Over time, they build up
that confidence
657
00:54:18,860 --> 00:54:22,659
and they just really, really try
to edge much closer
658
00:54:22,660 --> 00:54:24,500
each and every time
and get a good look.
659
00:54:26,940 --> 00:54:29,779
I do have other tricks, as well.
I'll sing through my snorkel.
660
00:54:29,780 --> 00:54:31,620
HUMMING
661
00:54:33,460 --> 00:54:36,139
You can be in the water
for seven, eight hours a day
662
00:54:36,140 --> 00:54:38,739
and you might only get two of these
passes for that whole day.
663
00:54:38,740 --> 00:54:41,979
And when they happen,
they're just mind-blowing.
664
00:54:41,980 --> 00:54:43,819
You've got this big, big animal.
665
00:54:43,820 --> 00:54:46,220
I mean, it's the size of a minibus,
coming to look at you.
666
00:54:49,300 --> 00:54:52,339
You can get out at the end of a day
and just have the biggest smile.
667
00:54:52,340 --> 00:54:54,739
I've just watched the sunset
from in the water.
668
00:54:54,740 --> 00:54:58,420
A whale nearly touched me.
It just doesn't get any better.
669
00:55:03,900 --> 00:55:05,619
'While our underwater crews
670
00:55:05,620 --> 00:55:08,299
'were rewarded with
spectacular interactions,
671
00:55:08,300 --> 00:55:11,219
'on Heron Island,
I had the opportunity
672
00:55:11,220 --> 00:55:13,260
'to meet one of
my favourite visitors.'
673
00:55:15,940 --> 00:55:17,380
The noddy.
674
00:55:19,060 --> 00:55:22,859
The birds' relaxed nature
and attachment to their nests
675
00:55:22,860 --> 00:55:26,060
meant we could tell their story
without disturbing them.
676
00:55:27,260 --> 00:55:28,900
Without deserting their nest.
677
00:55:32,540 --> 00:55:33,859
Hello.
678
00:55:33,860 --> 00:55:36,219
But when cameraman, Mike Pitts
returns
679
00:55:36,220 --> 00:55:38,659
to film the hatchlings
three months later,
680
00:55:38,660 --> 00:55:41,540
disaster hits the island
on his first night.
681
00:55:43,140 --> 00:55:44,780
THUNDERCLAP
682
00:55:49,420 --> 00:55:51,660
WIND GUSTS
683
00:55:58,980 --> 00:56:02,619
The following morning, Mike discovers
that the storm has destroyed
684
00:56:02,620 --> 00:56:04,860
the very spot where I had filmed.
685
00:56:06,980 --> 00:56:09,179
It was shattered.
It was like a warzone.
686
00:56:09,180 --> 00:56:12,379
You think of these idyllic,
tropical islands
687
00:56:12,380 --> 00:56:14,380
and you couldn't be further from
the truth.
688
00:56:21,340 --> 00:56:22,819
Are you still rolling?
689
00:56:22,820 --> 00:56:25,539
You can see that
many of the trees are down.
690
00:56:25,540 --> 00:56:28,019
And it's brought down the chicks
with them and the nests.
691
00:56:28,020 --> 00:56:30,859
Eggs are smashed, chicks are dying.
692
00:56:30,860 --> 00:56:32,899
And the chicks that have survived
693
00:56:32,900 --> 00:56:35,419
are now on these trunks and branches
694
00:56:35,420 --> 00:56:37,139
and on the ground
of the forest itself,
695
00:56:37,140 --> 00:56:39,419
hoping for their parent birds
696
00:56:39,420 --> 00:56:41,619
to find them
and bring the food they need.
697
00:56:41,620 --> 00:56:43,419
But the parent birds are so confused
698
00:56:43,420 --> 00:56:45,499
because so many of the trees
are gone.
699
00:56:45,500 --> 00:56:49,260
It's very disheartening to see it,
and, er... it's a real sad sight.
700
00:56:53,180 --> 00:56:56,420
I'd never seen the aftermath
of such a strong storm.
701
00:56:57,500 --> 00:57:00,820
But, of course, your emotions
always get the better of you.
702
00:57:04,980 --> 00:57:09,099
You still see survivors,
just sitting on the nest,
703
00:57:09,100 --> 00:57:11,659
protecting the egg or the chick.
704
00:57:11,660 --> 00:57:14,420
It really is quite amazing,
their resilience.
705
00:57:15,940 --> 00:57:19,459
It puts the whole reef
into a context whereby
706
00:57:19,460 --> 00:57:22,219
you're following
the rhythms of life.
707
00:57:22,220 --> 00:57:25,019
We were there to record it
and film it
708
00:57:25,020 --> 00:57:27,140
and that's part of
the Great Reef story.
61028
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