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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 kilometres
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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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.'

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Roger. Venting now.

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There we are!

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'The sub not only gives us
stunning 360-degree views,

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'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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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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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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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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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 travelling
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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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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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 travelled 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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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 gruelling 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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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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This is looking great. We're getting
much better nesting success,

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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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Inevitably, the tiny, defenceless
hatchlings

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attract scores of predators.

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SQUAWKING

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Terns and herons patrol the beach.

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And in the shallows,
reef sharks lie in wait.

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Great numbers are lost,

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but enough will make it to the ocean
to ensure the species' survival.

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As the young turtles leave the reef,

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they get a helping hand
from the ocean currents.

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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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to the very same beaches
where they hatched.

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Remote islands like Raine
are hugely important

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to both turtles and birds

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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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and there's a habitat
to suit every visitor.

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Turtles need sandy beaches

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and many birds need trees.

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'The Alucia is taking us
to one of these wooded islands

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'near the southern end
of the Great Barrier.'

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Almost 1,000 miles south of Raine
is Heron Island.

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And every year, it attracts

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thousands of birds
seeking somewhere safe to nest.

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The island is surrounded by
fragile coral reef.

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So to reach the shore, I'm leaving
the Alucia anchored in deeper water.

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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.

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But the moment comes in the year
when, in fact, a bird has to lay.

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And to do that,
it has to go onto land.

241
00:21:56,940 --> 00:22:01,220
And the number of sites where they
can build a nest are very limited.

242
00:22:01,220 --> 00:22:04,980
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 --> 00:22:19,660
'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 --> 00:22:32,180
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 --> 00:22:59,660
'The first indication that this
secretive character has arrived

252
00:22:59,660 --> 00:23:02,300
'is its rather unusual song.'

253
00:23:02,300 --> 00:23:04,340
WAILING

254
00:23:09,860 --> 00:23:12,540
The old sailors used to call it
the ghost bird

255
00:23:12,540 --> 00:23:15,340
because of its extraordinary call.

256
00:23:15,340 --> 00:23:18,780
More properly known as
the wedge-tailed shearwater.

257
00:23:18,780 --> 00:23:20,860
WAILING

258
00:23:28,180 --> 00:23:33,020
'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 --> 00:23:54,620
These are true seafaring birds.
Out at sea when they're feeding,

261
00:23:54,620 --> 00:23:57,620
they are very expert at flying
just above the surface,

262
00:23:57,620 --> 00:24:00,820
or indeed swimming on the surface,
catching their fish.

263
00:24:00,820 --> 00:24:02,980
But when they come into land, well,

264
00:24:02,980 --> 00:24:05,700
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 --> 00:24:13,660
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 --> 00:24:35,580
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 --> 00:24:45,020
These birds have travelled

271
00:24:45,020 --> 00:24:46,940
an extraordinary 4,000 miles
to get here.

272
00:24:51,340 --> 00:24:53,580
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 --> 00:25:00,660
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 --> 00:25:10,700
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 --> 00:25:23,500
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 --> 00:25:44,860
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 --> 00:25:56,220
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 --> 00:26:38,300
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 --> 00:26:56,580
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 --> 00:27:09,740
As it spins clockwise,
it pulls up cool waters from below,

294
00:27:09,740 --> 00:27:14,540
which bring rich nutrients
to the surface.

295
00:27:14,540 --> 00:27:20,060
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 --> 00:27:28,820
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 --> 00:27:39,220
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 --> 00:27:51,380
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 --> 00:27:58,900
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 --> 00:28:07,300
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 --> 00:28:16,780
But there are still large animals

308
00:28:16,780 --> 00:28:20,860
whose movements remain
something of a mystery.

309
00:28:20,860 --> 00:28:24,300
Manta rays are the nomads
of the reef.

310
00:28:24,300 --> 00:28:26,540
They're huge creatures.

311
00:28:26,540 --> 00:28:30,140
They can measure 15 feet,
five metres across

312
00:28:30,140 --> 00:28:33,660
and weigh almost
one-and-a-half tonnes.

313
00:28:33,660 --> 00:28:36,780
They come to the reef to feed on
plankton,

314
00:28:36,780 --> 00:28:39,300
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 --> 00:28:50,380
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 --> 00:29:00,660
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 --> 00:29:15,100
These are the beauty salons
of the reef.

321
00:29:15,100 --> 00:29:18,020
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 --> 00:29:28,100
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 --> 00:29:37,220
They provide a vital service,

326
00:29:37,220 --> 00:29:41,260
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 --> 00:29:49,820
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 --> 00:30:19,700
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 --> 00:31:11,900
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 --> 00:31:30,620
She's broken the rules,
and there's a price pay.

343
00:31:30,620 --> 00:31:33,460
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 --> 00:31:49,420
If the bite is a one-off,
the manta ray will return.

347
00:31:49,420 --> 00:31:52,660
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 --> 00:32:03,300
Fortunately,
it seems her indiscretion

350
00:32:03,300 --> 00:32:05,500
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 --> 00:32:16,060
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 --> 00:32:29,500
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 --> 00:32:45,380
Lady Elliot Island
is like the centre of the universe

357
00:32:45,380 --> 00:32:48,660
for manta rays on
the east coast of Australia.

358
00:32:48,660 --> 00:32:50,460
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 --> 00:32:57,180
We are doing several things
with the manta rays.

361
00:32:57,180 --> 00:32:59,100
First of all, we're trying
to understand

362
00:32:59,100 --> 00:33:00,940
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 --> 00:33:10,500
This is a key part of Kathy's work in
tracking these gentle ocean giants.

365
00:33:10,500 --> 00:33:13,780
And the team has already attached
acoustic tags

366
00:33:13,780 --> 00:33:17,300
to a large number of study animals.

367
00:33:17,300 --> 00:33:21,460
We have six acoustic listening
stations around Lady Elliot Island.

368
00:33:21,460 --> 00:33:23,300
And as an animal goes past,

369
00:33:23,300 --> 00:33:26,780
within a 500-metre 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 --> 00:33:36,900
That has revealed that many
of the mantas have travelled

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 --> 00:33:46,660
One of the lovely things
about working with manta rays

374
00:33:46,660 --> 00:33:48,460
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 --> 00:34:08,180
It's really unusual behaviour.

377
00:34:08,180 --> 00:34:10,060
Most sharks and rays
have no interest

378
00:34:10,060 --> 00:34:12,860
in having any interaction
with people whatsoever.

379
00:34:12,860 --> 00:34:16,820
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 --> 00:34:25,940
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 --> 00:34:50,500
We need to get in underneath
the animal

385
00:34:50,500 --> 00:34:53,060
and take a photograph from below.

386
00:34:53,060 --> 00:34:57,100
Each individual has a very unique
spot pattern

387
00:34:57,100 --> 00:35:00,820
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 --> 00:35:10,420
When Project Manta began
seven years ago,

390
00:35:10,420 --> 00:35:14,980
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 --> 00:35:25,140
I think manta ray research is quite
important

393
00:35:25,140 --> 00:35:28,100
because first of all,
this is a very large-bodied animal

394
00:35:28,100 --> 00:35:31,260
that very little information
is known about.

395
00:35:31,260 --> 00:35:33,100
Various places around the world,

396
00:35:33,100 --> 00:35:36,020
the manta ray populations
have declined dramatically,

397
00:35:36,020 --> 00:35:39,700
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 --> 00:35:56,460
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 --> 00:36:28,780
'This part of tropical Australia

407
00:36:28,780 --> 00:36:32,620
'lies right in the path of regular
seasonal cyclones.

408
00:36:32,620 --> 00:36:35,780
'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 --> 00:36:41,940
This tangle of limestone walls

411
00:36:41,940 --> 00:36:45,980
acts as a barrier
against the open ocean.

412
00:36:45,980 --> 00:36:50,460
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 --> 00:36:58,220
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 --> 00:37:33,260
WHALE SONG

418
00:37:33,260 --> 00:37:35,060
Weighing up to 40 tonnes,

419
00:37:35,060 --> 00:37:38,180
they're the largest of
the Great Barrier Reef's visitors

420
00:37:38,180 --> 00:37:41,300
and they have also travelled
great distances to get here.

421
00:37:51,540 --> 00:37:55,940
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 --> 00:38:14,780
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 --> 00:38:25,140
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 --> 00:38:41,020
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 --> 00:38:57,460
In fact, there's one species which
does quite the opposite.

433
00:38:57,460 --> 00:39:01,300
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 --> 00:39:24,060
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 --> 00:39:33,980
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 --> 00:39:59,780
Dr Alistair Birtles knows more about

443
00:39:59,780 --> 00:40:03,460
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 --> 00:40:19,260
The very first time I got in
the water, um...

447
00:40:19,260 --> 00:40:25,420
was with a degree of apprehension,
great excitement.

448
00:40:25,420 --> 00:40:29,460
Um...I don't think I'd ever been
in the water with a whale before.

449
00:40:29,460 --> 00:40:33,780
And the first thing you see
is the white shoulder, um...

450
00:40:33,780 --> 00:40:37,940
and then the rest of the grey animal
emerges around it.

451
00:40:37,940 --> 00:40:41,180
It's very special being in the water

452
00:40:41,180 --> 00:40:44,060
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 --> 00:40:53,020
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 --> 00:41:02,340
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 --> 00:41:11,140
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 --> 00:41:20,540
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 --> 00:41:34,620
It is entirely the world's curiosity
that brings them in.

464
00:41:34,620 --> 00:41:37,700
I think we're a rather
strange object.

465
00:41:37,700 --> 00:41:40,500
We're a visitor into their world.

466
00:41:40,500 --> 00:41:44,300
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 --> 00:41:53,740
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 --> 00:42:06,540
She has a bent-over dorsal fin

472
00:42:06,540 --> 00:42:11,300
from I think where she was
fairly savagely mauled by a shark.

473
00:42:11,300 --> 00:42:14,340
And last year's encounter
was a particularly special one

474
00:42:14,340 --> 00:42:16,580
because she had a calf with her.

475
00:42:16,580 --> 00:42:20,580
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 --> 00:42:36,380
What Birtles and his team
want to discover

478
00:42:36,380 --> 00:42:38,660
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 --> 00:42:46,180
There are a number of clues.

481
00:42:46,180 --> 00:42:50,020
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 socialising
going on.

483
00:42:54,020 --> 00:42:57,540
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 --> 00:43:14,780
And then there's an extraordinary
sound they make

487
00:43:14,780 --> 00:43:18,020
which the researcher who labelled it

488
00:43:18,020 --> 00:43:21,100
called it the Star Wars sound.

489
00:43:21,100 --> 00:43:24,300
I thought it was a little more like
Beethoven's Fifth

490
00:43:24,300 --> 00:43:28,620
because it's got a triple beat
and then a long shwang

491
00:43:28,620 --> 00:43:30,540
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 --> 00:43:38,780
WHALE SONG

495
00:43:38,780 --> 00:43:42,860
When you hear it underwater, it kind
of reverberates through your chest.

496
00:43:42,860 --> 00:43:44,860
It's a very powerful sound.

497
00:43:44,860 --> 00:43:46,900
WHALE SONG

498
00:43:50,340 --> 00:43:52,980
The song is only produced by males

499
00:43:52,980 --> 00:43:55,820
and it's thought to be related to
courtship.

500
00:43:55,820 --> 00:43:57,940
WHALE SONG

501
00:43:57,940 --> 00:44:00,900
Curiously, two thirds of
the individuals

502
00:44:00,900 --> 00:44:03,500
Alistair encounters are adolescents.

503
00:44:05,180 --> 00:44:09,740
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 --> 00:44:17,220
Though Birtles' team has amassed

506
00:44:17,220 --> 00:44:19,380
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 --> 00:44:34,220
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 --> 00:44:48,660
The diver has to get into position,

513
00:44:48,660 --> 00:44:51,700
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 --> 00:45:22,580
After initially taking fright,

517
00:45:22,580 --> 00:45:25,860
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 --> 00:45:35,980
The tracking data the team is now
collecting

520
00:45:35,980 --> 00:45:40,020
may reveal the piece of the puzzle
that, until now, has been missing.

521
00:45:40,020 --> 00:45:43,700
So for 20 years, we've been
studying what the whales do

522
00:45:43,700 --> 00:45:46,140
in this area of the Great Barrier
Reef.

523
00:45:46,140 --> 00:45:48,980
We know they're only here
for a few weeks

524
00:45:48,980 --> 00:45:51,020
and we had no idea where they went

525
00:45:51,020 --> 00:45:53,260
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 --> 00:45:59,340
It really is an extraordinary
journey

528
00:45:59,340 --> 00:46:01,580
that we now know that they make.

529
00:46:01,580 --> 00:46:05,180
Spot, the young male that was
the first ever minke

530
00:46:05,180 --> 00:46:09,740
to have a satellite tag attached
in 2013,

531
00:46:09,740 --> 00:46:15,620
he travelled over 7,000 kilometres
deep into the Subantarctic.

532
00:46:15,620 --> 00:46:21,100
That's an extraordinary journey
for what is a little whale, to make.

533
00:46:21,100 --> 00:46:25,020
The tagging tells us where
the whales are travelling fast

534
00:46:25,020 --> 00:46:27,940
and where they're spending
extra time.

535
00:46:27,940 --> 00:46:31,540
There's a few places along the east
coast of Australia and Bass Strait

536
00:46:31,540 --> 00:46:35,500
where they may spend one,
two or even three weeks of time

537
00:46:35,500 --> 00:46:38,700
milling around, probably feeding.

538
00:46:38,700 --> 00:46:42,460
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 --> 00:46:49,140
For Birtles, it's not just about

541
00:46:49,140 --> 00:46:52,020
solving the mystery
of where the whales go.

542
00:46:52,020 --> 00:46:55,500
I am worried about them
when they leave the reef.

543
00:46:55,500 --> 00:46:57,820
The dwarf minkes are well protected

544
00:46:57,820 --> 00:46:59,740
when they're in
the Great Barrier Reef,

545
00:46:59,740 --> 00:47:05,140
but when they leave there,
they face many threats and dangers

546
00:47:05,140 --> 00:47:08,820
and they have to cross
major shipping channels.

547
00:47:08,820 --> 00:47:12,740
There are all sorts of threats
from fishing.

548
00:47:12,740 --> 00:47:17,580
I mean, if commercial whaling
is resumed in the Southern Ocean,

549
00:47:17,580 --> 00:47:21,300
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 --> 00:47:33,980
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 --> 00:47:44,980
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 --> 00:48:00,420
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 --> 00:48:14,380
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 --> 00:48:30,900
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 --> 00:48:46,140
..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 --> 00:48:53,420
THUNDERCLAP

568
00:48:53,420 --> 00:48:55,500
We'll meet the extraordinary people

569
00:48:55,500 --> 00:48:57,620
who are doing everything
in their power

570
00:48:57,620 --> 00:48:59,940
to protect this marine paradise.

571
00:48:59,940 --> 00:49:03,980
It is one of the most magnificent
ecosystems on the planet.

572
00:49:03,980 --> 00:49:06,260
What's really quite shocking is
that we may lose it

573
00:49:06,260 --> 00:49:09,140
before we truly understand it.

574
00:49:09,140 --> 00:49:12,500
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 --> 00:49:24,300
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 --> 00:49:47,460
For this episode, one of
our underwater teams

579
00:49:47,460 --> 00:49:50,100
travelled to Lady Elliot Island
in the south.

580
00:49:54,820 --> 00:49:57,380
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 --> 00:50:11,660
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 --> 00:50:18,420
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 --> 00:50:28,660
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 --> 00:50:37,500
Manta rays may be inquisitive,
but they can easily be spooked.

590
00:50:37,500 --> 00:50:40,460
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 --> 00:50:47,460
You are bulky and clumsy,

593
00:50:47,460 --> 00:50:49,620
you've got large cameras, lights.

594
00:50:49,620 --> 00:50:54,700
So what you don't want to do
is to obstruct the manta ray.

595
00:50:54,700 --> 00:50:58,340
The manta ray might get disturbed
and it'll just swim off.

596
00:50:58,340 --> 00:51:00,580
I generally keep as low as possible.

597
00:51:00,580 --> 00:51:03,420
So your profile sort of matches in
with the reef.

598
00:51:03,420 --> 00:51:05,500
And so what you notice
after a while is

599
00:51:05,500 --> 00:51:08,900
the manta rays will come closer
and closer and closer to you.

600
00:51:08,900 --> 00:51:13,820
And I can literally... I feel them
brushing over my head as they go.

601
00:51:13,820 --> 00:51:16,660
While the team's objective
was to film the cleaning station,

602
00:51:16,660 --> 00:51:18,460
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 --> 00:51:26,300
We were close to the end of the dive

605
00:51:26,300 --> 00:51:29,020
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 --> 00:51:37,980
I saw Kathy and suddenly
she zoomed off and we followed.

608
00:51:37,980 --> 00:51:41,620
And I could see out in the distance,
there was a male above a female

609
00:51:41,620 --> 00:51:44,980
and he was following her every move

610
00:51:44,980 --> 00:51:47,100
as she moved through the water.

611
00:51:47,100 --> 00:51:48,700
Kathy got really excited.

612
00:51:51,180 --> 00:51:53,660
They were undergoing behaviour
I'd never seen before.

613
00:51:53,660 --> 00:51:55,820
I'd seen various types of courtship
behaviour

614
00:51:55,820 --> 00:51:58,020
that involves having trains,

615
00:51:58,020 --> 00:52:01,300
where there's a female at the front
followed by several males.

616
00:52:01,300 --> 00:52:05,180
What was happening between these two
was really quite unique.

617
00:52:05,180 --> 00:52:08,420
The male was obviously trying
to court her,

618
00:52:08,420 --> 00:52:10,940
but in a very unusual way.

619
00:52:10,940 --> 00:52:12,940
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 --> 00:52:19,780
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 --> 00:52:26,100
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 --> 00:52:33,620
And all of sudden, she'd just fling
up into the air to shake him off

626
00:52:33,620 --> 00:52:35,660
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 --> 00:52:48,860
I knew it was something very special
because,

629
00:52:48,860 --> 00:52:51,900
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 --> 00:53:00,020
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 --> 00:53:07,740
In the far north, another wildlife
crew had their sights set

634
00:53:07,740 --> 00:53:11,540
on filming a very special
seasonal visitor.

635
00:53:11,540 --> 00:53:15,100
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 --> 00:53:21,140
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 --> 00:53:28,620
It's a little bit unnerving
sometimes jumping in

640
00:53:28,620 --> 00:53:32,060
and seeing a seven-tonne,
seven-metre animal

641
00:53:32,060 --> 00:53:34,020
come out from the gloom.

642
00:53:34,020 --> 00:53:36,780
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 --> 00:53:42,460
Every animal presents
a very different challenge

645
00:53:42,460 --> 00:53:44,500
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 --> 00:53:53,860
It's sometimes a game of
cat and mouse, in a way.

648
00:53:53,860 --> 00:53:56,500
Because if you're not looking,
they tend to come a lot closer.

649
00:53:56,500 --> 00:53:59,340
So if I can see a whale approaching
in the distance

650
00:53:59,340 --> 00:54:02,060
and I know it's going to be
a good approach this time,

651
00:54:02,060 --> 00:54:04,220
I'll purposely hold off
and turn my dome around

652
00:54:04,220 --> 00:54:07,260
and actually see in the reflection
of the dome the whale coming to me

653
00:54:07,260 --> 00:54:10,540
and then, when I think it's probably
about five to six metres away,

654
00:54:10,540 --> 00:54:13,340
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 --> 00:54:18,860
Over time, they build up
that confidence

657
00:54:18,860 --> 00:54:22,660
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 --> 00:54:29,780
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 --> 00:54:36,140
You can be in the water
for seven, eight hours a day

662
00:54:36,140 --> 00:54:38,740
and you might only get two of these
passes for that whole day.

663
00:54:38,740 --> 00:54:41,980
And when they happen,
they're just mind-blowing.

664
00:54:41,980 --> 00:54:43,820
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 --> 00:54:52,340
You can get out at the end of a day
and just have the biggest smile.

667
00:54:52,340 --> 00:54:54,740
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 --> 00:55:05,620
'While our underwater crews

670
00:55:05,620 --> 00:55:08,300
'were rewarded with
spectacular interactions,

671
00:55:08,300 --> 00:55:11,220
'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 --> 00:55:22,860
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 --> 00:55:33,860
Hello.

678
00:55:33,860 --> 00:55:36,220
But when cameraman, Mike Pitts
returns

679
00:55:36,220 --> 00:55:38,660
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 --> 00:56:02,620
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 --> 00:56:09,180
It was shattered.
It was like a warzone.

686
00:56:09,180 --> 00:56:12,380
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 --> 00:56:22,820
Are you still rolling?

689
00:56:22,820 --> 00:56:25,540
You can see that
many of the trees are down.

690
00:56:25,540 --> 00:56:28,020
And it's brought down the chicks
with them and the nests.

691
00:56:28,020 --> 00:56:30,860
Eggs are smashed, chicks are dying.

692
00:56:30,860 --> 00:56:32,900
And the chicks that have survived

693
00:56:32,900 --> 00:56:35,420
are now on these trunks and branches

694
00:56:35,420 --> 00:56:37,140
and on the ground
of the forest itself,

695
00:56:37,140 --> 00:56:39,420
hoping for their parent birds

696
00:56:39,420 --> 00:56:41,620
to find them
and bring the food they need.

697
00:56:41,620 --> 00:56:43,420
But the parent birds are so confused

698
00:56:43,420 --> 00:56:45,500
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 --> 00:57:09,100
You still see survivors,
just sitting on the nest,

703
00:57:09,100 --> 00:57:11,660
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 --> 00:57:19,460
It puts the whole reef
into a context whereby

706
00:57:19,460 --> 00:57:22,220
you're following
the rhythms of life.

707
00:57:22,220 --> 00:57:25,020
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.