Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:04,280 --> 00:00:05,680
In this series,
2
00:00:05,680 --> 00:00:09,280
I have travelled the length and breadth of the Great Barrier Reef...
3
00:00:13,520 --> 00:00:16,920
..and used the latest techniques to watch its wildlife.
4
00:00:26,360 --> 00:00:30,040
But the reef has one more story to tell.
5
00:00:32,880 --> 00:00:35,560
The residents of this marine paradise
6
00:00:35,560 --> 00:00:39,600
have seen their habitat change rapidly within the last few decades.
7
00:00:41,240 --> 00:00:43,640
And time is running out for them.
8
00:00:48,280 --> 00:00:51,760
The Barrier Reef is facing one of the most serious challenges
9
00:00:51,760 --> 00:00:54,160
to its continued existence -
10
00:00:54,160 --> 00:00:56,080
the effect of human beings.
11
00:00:57,920 --> 00:00:59,640
But there is hope.
12
00:01:01,520 --> 00:01:04,440
This time, our research vessel, the Alucia,
13
00:01:04,440 --> 00:01:07,120
will be taking me to meet teams of scientists
14
00:01:07,120 --> 00:01:10,680
who are developing new ways to try and save it.
15
00:01:11,960 --> 00:01:14,720
And I'll be going to its deepest parts,
16
00:01:14,720 --> 00:01:16,720
where new discoveries are being made
17
00:01:16,720 --> 00:01:19,440
that might hold clues to its survival.
18
00:01:19,440 --> 00:01:22,720
Nobody has ever dived as deep as this before
19
00:01:22,720 --> 00:01:24,240
on the Great Barrier Reef.
20
00:01:26,240 --> 00:01:31,120
This is one of the greatest and most important ecosystems on the planet -
21
00:01:31,120 --> 00:01:34,000
and what happens here affects us all.
22
00:01:35,480 --> 00:01:39,240
So, what does the future hold for this complex wonder?
23
00:01:51,320 --> 00:01:54,160
I'm travelling along Australia's north east coast
24
00:01:54,160 --> 00:01:55,880
to look at one of the greatest
25
00:01:55,880 --> 00:01:59,600
and most splendid natural treasures that the world possesses -
26
00:01:59,600 --> 00:02:02,480
a chain of tropical islands and coral reefs
27
00:02:02,480 --> 00:02:05,760
that lies between the coast and the open ocean.
28
00:02:12,360 --> 00:02:15,480
I will never forget the first time I came here.
29
00:02:18,880 --> 00:02:20,920
YOUNGER DAVID: 'And what a world this was -
30
00:02:20,920 --> 00:02:23,800
'beneath me lay an endless landscape of coral,
31
00:02:23,800 --> 00:02:26,800
'of every conceivable colour and shape.'
32
00:02:38,400 --> 00:02:42,720
It was unimaginable then to think that we might ever lose the reef.
33
00:02:47,240 --> 00:02:51,160
But now, I've returned, and I can see that the reef is changing.
34
00:02:54,600 --> 00:02:58,880
In the last 30 years, almost half the coral has disappeared.
35
00:03:02,480 --> 00:03:06,680
The greatest concern now is that we might lose the reef altogether.
36
00:03:17,120 --> 00:03:20,280
Parts of the Great Barrier Reef still remain a mystery.
37
00:03:20,280 --> 00:03:22,760
Its immense size and remote depths
38
00:03:22,760 --> 00:03:25,680
make it extremely difficult to explore.
39
00:03:29,600 --> 00:03:32,920
But today, exciting new technology has made it possible
40
00:03:32,920 --> 00:03:37,320
to survey the entire reef from top to bottom.
41
00:03:37,320 --> 00:03:40,120
And that is revealing extraordinary things
42
00:03:40,120 --> 00:03:43,720
about the way in which the reef itself has evolved over time.
43
00:03:45,720 --> 00:03:47,800
By looking into the reef's past,
44
00:03:47,800 --> 00:03:50,640
we may discover something about its future.
45
00:03:52,360 --> 00:03:56,000
So, I'm meeting marine geologist Dr Robin Beaman.
46
00:03:58,600 --> 00:04:00,520
'He is on board the Alucia
47
00:04:00,520 --> 00:04:03,600
'and shows me some of his remarkable discoveries.'
48
00:04:04,960 --> 00:04:08,080
This is a depth model of the Great Barrier Reef -
49
00:04:08,080 --> 00:04:10,160
of the entire Great Barrier Reef.
50
00:04:10,160 --> 00:04:12,600
And there's a whole lot of different tools we use,
51
00:04:12,600 --> 00:04:14,920
the main one being multibeam echosounders,
52
00:04:14,920 --> 00:04:17,440
so it gives you a scan of the seafloor
53
00:04:17,440 --> 00:04:22,040
and we can actually map great areas of the continental shelf.
54
00:04:22,040 --> 00:04:24,360
This white part is land?
55
00:04:24,360 --> 00:04:25,520
That's right.
56
00:04:25,520 --> 00:04:30,160
So, everything that's coloured rainbow colours is under water.
57
00:04:30,160 --> 00:04:33,920
'By combining computer modelling and deep sea surveying,
58
00:04:33,920 --> 00:04:36,160
'Beaman has discovered new evidence
59
00:04:36,160 --> 00:04:39,600
'that the reef has already experienced great changes.'
60
00:04:42,160 --> 00:04:44,240
As a scientist - as geological scientists -
61
00:04:44,240 --> 00:04:46,560
we're trying to understand how the Great Barrier Reef
62
00:04:46,560 --> 00:04:48,600
has responded to changes in the past
63
00:04:48,600 --> 00:04:51,640
and there are clues there as to what the Great Barrier Reef has done,
64
00:04:51,640 --> 00:04:55,400
so if I zoom back, you can see, geologically,
65
00:04:55,400 --> 00:04:57,880
it's gone through some dramatic changes.
66
00:05:01,320 --> 00:05:05,280
Beaman's scans showed traces of an ancient reef
67
00:05:05,280 --> 00:05:08,080
that thrived over the last half million years
68
00:05:08,080 --> 00:05:11,760
and is now hidden along the edge of this great drop-off.
69
00:05:14,120 --> 00:05:18,200
This earlier reef existed long before the one we know today.
70
00:05:18,200 --> 00:05:20,840
It lay up to 70 metres deep
71
00:05:20,840 --> 00:05:24,600
and stretched nearly unbroken for more than 500 miles.
72
00:05:27,520 --> 00:05:30,920
It's been described as the world's largest fossil.
73
00:05:33,000 --> 00:05:36,360
This is what the older Great Barrier Reef looked like.
74
00:05:36,360 --> 00:05:38,200
And we call these "drowned reefs" -
75
00:05:38,200 --> 00:05:41,160
they're drowned in the sense that the water over them is so deep
76
00:05:41,160 --> 00:05:43,000
that the reef no longer grows.
77
00:05:45,160 --> 00:05:48,320
These ancient reefs were drowned by dramatic climate changes
78
00:05:48,320 --> 00:05:50,480
that caused sea levels to rise.
79
00:05:52,160 --> 00:05:55,280
This last happened less than 14,000 years ago.
80
00:05:56,920 --> 00:06:00,000
So, water released from the melting icecaps
81
00:06:00,000 --> 00:06:03,560
- is going to start flooding across here, is it?
- That's right.
82
00:06:03,560 --> 00:06:06,320
The sea level was high enough to actually inundate
83
00:06:06,320 --> 00:06:08,760
and cover these old limestone hills
84
00:06:08,760 --> 00:06:12,080
and created the Great Barrier Reef that we know today.
85
00:06:12,080 --> 00:06:15,040
So, the changes that we're seeing going on now
86
00:06:15,040 --> 00:06:18,080
are nothing new, in terms of change.
87
00:06:18,080 --> 00:06:21,400
I mean, the Barrier Reef has always been changing.
88
00:06:21,400 --> 00:06:23,000
We do find it's quite robust.
89
00:06:23,000 --> 00:06:24,880
It has actually reformed,
90
00:06:24,880 --> 00:06:30,160
despite these catastrophic changes that have occurred.
91
00:06:31,320 --> 00:06:36,360
It's been exposed and flooded at least four times that we know of.
92
00:06:36,360 --> 00:06:38,200
To us, it's astounding.
93
00:06:41,480 --> 00:06:44,960
This new insight into the ancient history of the reef
94
00:06:44,960 --> 00:06:48,560
shows that, given enough time, it can regenerate.
95
00:06:53,080 --> 00:06:56,200
It seems that if seawater is clear and warm,
96
00:06:56,200 --> 00:06:58,960
simple organisms will eventually evolve
97
00:06:58,960 --> 00:07:01,680
that can build limestone homes to protect themselves
98
00:07:01,680 --> 00:07:03,600
from the waves and their enemies.
99
00:07:05,800 --> 00:07:10,280
But most of these events started long before human beings appeared on Earth
100
00:07:10,280 --> 00:07:13,000
and took many thousands of years to complete.
101
00:07:16,160 --> 00:07:20,040
We now know the reef has dwindled and recovered
102
00:07:20,040 --> 00:07:23,000
many times in its long history,
103
00:07:23,000 --> 00:07:27,920
but it also has to withstand a major change every 24 hours,
104
00:07:27,920 --> 00:07:30,960
as the tide retreats and comes back.
105
00:07:35,480 --> 00:07:38,800
At low tide, the water drains away very quickly,
106
00:07:38,800 --> 00:07:42,520
leaving the topmost community of creatures dangerously exposed.
107
00:07:48,240 --> 00:07:50,600
Some are washed out with the tide.
108
00:07:56,880 --> 00:07:58,640
Others swim to safety.
109
00:08:01,160 --> 00:08:03,600
But the coral polyps can't move.
110
00:08:08,160 --> 00:08:10,560
Temperatures on the surface of the reef
111
00:08:10,560 --> 00:08:13,560
can now reach a scorching 30 degrees centigrade.
112
00:08:16,520 --> 00:08:19,160
The exposed corals could easily dry out
113
00:08:19,160 --> 00:08:22,160
and be damaged by intense ultraviolet rays.
114
00:08:24,440 --> 00:08:27,320
But corals have ways of protecting themselves.
115
00:08:29,520 --> 00:08:33,360
When exposed to air, they produce huge amounts of mucus,
116
00:08:33,360 --> 00:08:36,360
which keeps them wet and acts like a sunscreen.
117
00:08:38,400 --> 00:08:43,080
This remarkable slime actually increases its UV resistance,
118
00:08:43,080 --> 00:08:45,800
becoming stronger if the temperatures soar.
119
00:08:47,680 --> 00:08:52,440
So, the coral manages to survive for the few hours that it's out of water.
120
00:08:55,880 --> 00:09:00,480
But there's one fish that manages to turn this exposure to its advantage.
121
00:09:13,080 --> 00:09:18,160
The epaulette shark remains on the reef even when the tide goes out.
122
00:09:18,160 --> 00:09:20,480
Of course, with so little water,
123
00:09:20,480 --> 00:09:23,360
it doesn't get as much oxygen as it requires normally,
124
00:09:23,360 --> 00:09:27,920
but it deals with that possibility by shutting off a part of its brain
125
00:09:27,920 --> 00:09:30,280
and so, reducing its oxygen demands.
126
00:09:31,800 --> 00:09:35,760
As the retreating tide exposes the topmost branches of the corals,
127
00:09:35,760 --> 00:09:39,960
the shark remains in the little pools between them for as long as it can.
128
00:09:42,480 --> 00:09:46,640
And then, it sets off to try and find food -
129
00:09:46,640 --> 00:09:51,560
shrimps, crabs and small worms that live on the reef.
130
00:09:51,560 --> 00:09:55,720
And it does that by exploiting another talent it has.
131
00:09:55,720 --> 00:09:57,760
It can, in effect, walk.
132
00:10:10,640 --> 00:10:14,560
It may be slow-going, but the little shark manages to make its way
133
00:10:14,560 --> 00:10:18,800
between the rocky pools to look for prey that may be imprisoned in them.
134
00:10:26,760 --> 00:10:28,480
It has the run of the place,
135
00:10:28,480 --> 00:10:31,920
until the tide returns once more to flood the reeftop.
136
00:10:46,440 --> 00:10:50,200
So, the inhabitants of the reef, each in its own way,
137
00:10:50,200 --> 00:10:53,560
deal with the daily hazards brought by exposure.
138
00:11:00,160 --> 00:11:03,600
But there is one catastrophe that can strike each year
139
00:11:03,600 --> 00:11:05,800
against which there is no defence.
140
00:11:14,040 --> 00:11:15,840
From November onwards,
141
00:11:15,840 --> 00:11:18,760
warm, moisture-laden winds from the northwest
142
00:11:18,760 --> 00:11:22,000
sweep down across these tropic seas
143
00:11:22,000 --> 00:11:24,560
and it's then that cyclones form.
144
00:11:27,840 --> 00:11:32,520
They are, in fact, the biggest killers of the reef's corals.
145
00:11:34,000 --> 00:11:38,680
But that doesn't mean that the corals are permanently destroyed.
146
00:11:38,680 --> 00:11:41,720
Their resilience once more comes apparent.
147
00:11:45,920 --> 00:11:49,000
And there's an extraordinary example of that
148
00:11:49,000 --> 00:11:51,080
in the most unlikely of places.
149
00:12:07,560 --> 00:12:11,040
This is the wreck of the SS Yongala.
150
00:12:14,440 --> 00:12:17,440
It was sunk by a cyclone in 1911.
151
00:12:23,040 --> 00:12:27,840
It lies 30 metres below the surface on a barren, sandy plain...
152
00:12:31,520 --> 00:12:34,920
..miles away from any natural coral reefs.
153
00:12:39,520 --> 00:12:42,360
By the time it was discovered, decades later,
154
00:12:42,360 --> 00:12:44,720
it had become an artificial reef...
155
00:12:47,200 --> 00:12:51,240
..and had been colonised by an extraordinary variety of life.
156
00:12:57,320 --> 00:13:00,200
It was an oasis in the featureless ocean.
157
00:13:16,520 --> 00:13:18,800
But in the century since it sank,
158
00:13:18,800 --> 00:13:22,560
the wreck has been hit repeatedly by more cyclones.
159
00:13:27,040 --> 00:13:29,560
The waters here are not deep
160
00:13:29,560 --> 00:13:34,400
so the turbulence created by a cyclone can reach the sea floor.
161
00:13:43,600 --> 00:13:46,160
THUNDERCLAP
162
00:13:52,360 --> 00:13:55,000
Cyclones travelling towards the coast
163
00:13:55,000 --> 00:13:57,840
can rip up hundreds of miles of coral.
164
00:14:02,680 --> 00:14:06,440
Captain Trevor Jackson, who has been diving on this wreck for decades,
165
00:14:06,440 --> 00:14:13,000
saw the devastating effects caused in 2011 by a category five cyclone.
166
00:14:14,480 --> 00:14:16,720
Cyclone Yahtzee, a massive system,
167
00:14:16,720 --> 00:14:19,040
crossed the coast just north of here.
168
00:14:19,040 --> 00:14:20,480
The cyclone was so large,
169
00:14:20,480 --> 00:14:23,560
it generated waves that exposed the top of the Yongala.
170
00:14:28,920 --> 00:14:31,640
THUNDERCLAP
171
00:14:40,400 --> 00:14:42,120
There was a lifting action...
172
00:14:45,120 --> 00:14:46,720
..and in the process,
173
00:14:46,720 --> 00:14:49,800
this scoured the top of the reef of all marine life.
174
00:15:01,320 --> 00:15:06,320
What was once a thriving ecosystem was now an almost bare skeleton.
175
00:15:10,920 --> 00:15:13,640
But amazingly, the reef on the Yongala
176
00:15:13,640 --> 00:15:16,400
began to repair itself within months.
177
00:15:21,720 --> 00:15:23,880
Green algae appeared on the wreck.
178
00:15:25,280 --> 00:15:28,800
Barnacles followed, allowing corals to get a grip.
179
00:15:36,040 --> 00:15:39,920
And soon, a new community had established itself.
180
00:16:05,160 --> 00:16:08,320
One of the things that makes the Yongala so unique
181
00:16:08,320 --> 00:16:12,920
is the way it rejuvenates itself after a major weather event.
182
00:16:12,920 --> 00:16:15,160
In the course of the last four or five years,
183
00:16:15,160 --> 00:16:17,600
about 80% of the reef has re-grown.
184
00:16:26,160 --> 00:16:30,440
The story of the Yongala shows that a coral reef can, remarkably,
185
00:16:30,440 --> 00:16:32,920
recover from natural disaster.
186
00:16:43,520 --> 00:16:46,560
And such recovery can be surprisingly quick
187
00:16:46,560 --> 00:16:49,040
when a reef is healthy and in balance.
188
00:16:52,040 --> 00:16:55,880
Most of the reef's inhabitants depend on one another for survival.
189
00:17:12,080 --> 00:17:15,480
But it is the coral that is the foundation of the reef
190
00:17:15,480 --> 00:17:19,600
and it plays a crucial role in many of the relationships.
191
00:17:28,880 --> 00:17:32,600
This is the crown-of-thorns starfish.
192
00:17:34,440 --> 00:17:37,080
For it, coral is food
193
00:17:37,080 --> 00:17:40,320
and it will eat relentlessly if not kept in check.
194
00:17:41,480 --> 00:17:43,920
But to other creatures, like the guard crab,
195
00:17:43,920 --> 00:17:45,640
coral is home.
196
00:17:50,920 --> 00:17:53,840
The crab is prepared to defend its patch
197
00:17:53,840 --> 00:17:57,040
from the carnivorous starfish at all costs.
198
00:18:02,000 --> 00:18:03,680
The crown-of-thorns, however,
199
00:18:03,680 --> 00:18:06,680
is much larger than most other starfish on the reef,
200
00:18:06,680 --> 00:18:11,080
so the tiny crab is forced to take a more stealthy approach.
201
00:18:15,600 --> 00:18:19,640
Hidden within the coral, it waits for its moment to attack.
202
00:18:34,200 --> 00:18:37,960
The starfish has left itself dangerously exposed,
203
00:18:37,960 --> 00:18:40,160
but the crab is cautious.
204
00:18:44,920 --> 00:18:47,760
When it can, the crab uses its powerful pincers
205
00:18:47,760 --> 00:18:51,960
to snip at the starfish's spines and tube-like feet...
206
00:19:04,960 --> 00:19:08,360
..before retreating back into the safety of the coral.
207
00:19:10,200 --> 00:19:12,400
The crab has won this battle.
208
00:19:15,040 --> 00:19:17,600
But recently, something has changed
209
00:19:17,600 --> 00:19:19,600
and the balance has been upset.
210
00:19:23,560 --> 00:19:26,960
The number of crown-of-thorns has increased dramatically
211
00:19:26,960 --> 00:19:29,720
and they've become a big problem on the reef.
212
00:19:35,640 --> 00:19:37,280
To find out more,
213
00:19:37,280 --> 00:19:41,880
the Alucia is taking me to a research station in the far north of the reef.
214
00:19:50,800 --> 00:19:55,560
It's situated on Lizard Island, where we can observe this problem up close.
215
00:20:00,960 --> 00:20:04,360
Lizard is surrounded by some of the most spectacular reefs
216
00:20:04,360 --> 00:20:06,080
on the entire barrier.
217
00:20:07,840 --> 00:20:11,920
But they are under attack from the coral-eating starfish.
218
00:20:13,560 --> 00:20:16,000
And at the island's research station,
219
00:20:16,000 --> 00:20:20,120
they've been studying why we might be seeing more of them than we used to.
220
00:20:29,840 --> 00:20:32,040
They have an extraordinary ability
221
00:20:32,040 --> 00:20:37,600
to suddenly increase vastly in numbers, like a plague.
222
00:20:37,600 --> 00:20:41,800
There have been three such plagues since the 1960s
223
00:20:41,800 --> 00:20:43,200
and, unfortunately,
224
00:20:43,200 --> 00:20:46,640
it seems as though we're in the middle, now, of a fourth.
225
00:20:48,280 --> 00:20:52,240
You might think that these plagues are just another natural disaster
226
00:20:52,240 --> 00:20:55,360
that the reef has had to withstand, like cyclones.
227
00:20:55,360 --> 00:20:58,120
There are reasons to suppose that, in fact,
228
00:20:58,120 --> 00:21:01,720
the plagues have been affected by human activity -
229
00:21:01,720 --> 00:21:06,640
either through an accumulation of run-off of fertilisers from the land
230
00:21:06,640 --> 00:21:10,520
that creates more food for the young starfish,
231
00:21:10,520 --> 00:21:12,520
or because we have overfished
232
00:21:12,520 --> 00:21:15,440
and so destroyed the natural balance of the reef.
233
00:21:16,920 --> 00:21:20,040
The starfish outbreaks have been responsible
234
00:21:20,040 --> 00:21:23,760
for over 40% of the coral loss of the last 30 years.
235
00:21:24,880 --> 00:21:29,520
It's just one of the huge changes here witnessed by Dr Charlie Veron.
236
00:21:31,080 --> 00:21:33,560
In 1972, Charlie was appointed
237
00:21:33,560 --> 00:21:37,440
the reef's first full-time coral scientist.
238
00:21:37,440 --> 00:21:40,640
He's gone on to become a world authority on coral
239
00:21:40,640 --> 00:21:43,920
and has identified a third of the world's known species.
240
00:21:45,280 --> 00:21:49,680
He was one of the first scientists to spend time in this underwater world
241
00:21:49,680 --> 00:21:52,720
and that was due to a particular piece of technology.
242
00:21:54,400 --> 00:21:58,640
What we knew about corals at the beginning of the scuba era
243
00:21:58,640 --> 00:22:00,680
was just almost nothing.
244
00:22:00,680 --> 00:22:03,680
So, scuba gear must have changed things radically.
245
00:22:03,680 --> 00:22:05,040
It changed everything.
246
00:22:05,040 --> 00:22:07,760
When you went down the face of a coral reef,
247
00:22:07,760 --> 00:22:11,680
you could see how corals fed, how they fought each other,
248
00:22:11,680 --> 00:22:13,400
how they reproduced and still,
249
00:22:13,400 --> 00:22:15,720
we're only just scratching the surface.
250
00:22:15,720 --> 00:22:18,040
Think of all the things that happen in a rainforest,
251
00:22:18,040 --> 00:22:19,440
how much we know about it.
252
00:22:19,440 --> 00:22:22,840
We haven't got a thousandth part of that information on the coral reef yet.
253
00:22:22,840 --> 00:22:25,160
'But since Charlie's first discoveries,
254
00:22:25,160 --> 00:22:27,760
'the reef has altered dramatically.'
255
00:22:27,760 --> 00:22:33,280
I've been going back to the same spots 10, 20, 30, 40 years ago
256
00:22:33,280 --> 00:22:36,000
and every time I go back,
257
00:22:36,000 --> 00:22:39,800
I'm sickened by some of the changes I've seen.
258
00:22:39,800 --> 00:22:42,240
Sometimes, I go back, I know it's the same spot
259
00:22:42,240 --> 00:22:43,960
and I can barely recognise it.
260
00:22:43,960 --> 00:22:46,240
Some species have been wiped out in the shallows now.
261
00:22:46,240 --> 00:22:48,480
It's already happened.
262
00:22:50,000 --> 00:22:54,320
What Charlie had witnessed were the effects of mankind upon the reef.
263
00:22:58,440 --> 00:23:03,520
When I myself first visited the Queensland coast almost 60 years ago,
264
00:23:03,520 --> 00:23:05,240
it was very different.
265
00:23:14,440 --> 00:23:17,600
Since then, like many coastlines around the world,
266
00:23:17,600 --> 00:23:20,480
there has been a massive increase in population
267
00:23:20,480 --> 00:23:22,880
and an explosion of industry.
268
00:23:37,560 --> 00:23:42,800
By 1975, the reef had been declared a National Marine Park.
269
00:23:42,800 --> 00:23:46,240
It was the biggest one of its kind in the world.
270
00:23:46,240 --> 00:23:49,760
But then, a new threat began to be recognised -
271
00:23:49,760 --> 00:23:53,480
not only to the reef, but to the world's oceans -
272
00:23:53,480 --> 00:23:54,960
climate change.
273
00:23:56,440 --> 00:24:00,000
THUNDERCLAPS
274
00:24:02,560 --> 00:24:06,400
There is more carbon dioxide in our atmosphere now
275
00:24:06,400 --> 00:24:09,600
than there has been in 800,000 years.
276
00:24:12,400 --> 00:24:15,560
Industrialised nations have been burning fossil fuels
277
00:24:15,560 --> 00:24:17,560
at an alarming rate.
278
00:24:19,320 --> 00:24:22,120
Global warming is slowly heating up our planet
279
00:24:22,120 --> 00:24:24,880
and threatens to cause huge problems for us all.
280
00:24:27,360 --> 00:24:32,800
Around 30% of the carbon dioxide we produce is absorbed by the ocean.
281
00:24:35,960 --> 00:24:39,200
As a result, we're seeing an increase in the temperature
282
00:24:39,200 --> 00:24:40,840
and acidity of our seas.
283
00:24:43,440 --> 00:24:46,720
Both are killing the inhabitants of the reef.
284
00:24:51,960 --> 00:24:54,160
But how quickly is it being damaged?
285
00:24:57,400 --> 00:25:02,320
To find out, I'm heading to meet Professor Ove Hoegh-Guldberg
286
00:25:02,320 --> 00:25:05,840
He's studying the effects of climate change on coral.
287
00:25:10,560 --> 00:25:12,720
Ove is based on Heron Island,
288
00:25:12,720 --> 00:25:16,080
near the southern end of the Great Barrier.
289
00:25:16,080 --> 00:25:20,360
Heron is a low, sandy island, 50 miles out from the mainland,
290
00:25:20,360 --> 00:25:22,000
right on the reef itself...
291
00:25:24,800 --> 00:25:28,040
..so its research station is very well-placed.
292
00:25:29,640 --> 00:25:32,320
Here, Ove is carrying out an experiment
293
00:25:32,320 --> 00:25:34,320
to see how the reef is going to cope.
294
00:25:35,440 --> 00:25:37,240
At the research station here,
295
00:25:37,240 --> 00:25:41,320
the experiment we're running is really climate change sped up.
296
00:25:42,440 --> 00:25:46,320
Because it's often hard for people to really get their heads around
297
00:25:46,320 --> 00:25:48,760
when you talk about global change over decades
298
00:25:48,760 --> 00:25:51,080
and what might happen to coral reefs.
299
00:25:51,080 --> 00:25:54,080
We have, essentially, in these experiments, sped things up
300
00:25:54,080 --> 00:25:56,400
so that you can literally, over a year,
301
00:25:56,400 --> 00:26:00,240
see the impacts of what might be occurring over the next hundred.
302
00:26:03,960 --> 00:26:07,200
Each of these tanks contains a miniature coral reef
303
00:26:07,200 --> 00:26:09,680
with the same species of coral.
304
00:26:09,680 --> 00:26:11,920
But each is being subjected to
305
00:26:11,920 --> 00:26:15,960
slightly different conditions of temperature and acidity -
306
00:26:15,960 --> 00:26:19,880
the two factors that are most likely to alter with climate change.
307
00:26:24,760 --> 00:26:29,040
Using these tanks, scientists have shown that increasing acidity
308
00:26:29,040 --> 00:26:32,720
restricts hard corals from building their limestone skeletons.
309
00:26:35,920 --> 00:26:37,840
And a rise in temperature -
310
00:26:37,840 --> 00:26:40,400
a single degree centigrade warmer than normal -
311
00:26:40,400 --> 00:26:42,960
can cause corals to become so stressed
312
00:26:42,960 --> 00:26:45,920
that they eject the photosynthesising algae
313
00:26:45,920 --> 00:26:48,640
that enable them to grow and give some colour.
314
00:26:53,840 --> 00:26:57,040
So they bleach, turning ghostly white.
315
00:27:07,400 --> 00:27:09,160
If you go back in time,
316
00:27:09,160 --> 00:27:13,920
you can see the big swings between ice ages and the warm periods
317
00:27:13,920 --> 00:27:16,360
where the Great Barrier Reef disappears and regrows
318
00:27:16,360 --> 00:27:18,960
and that's happened numerous times.
319
00:27:18,960 --> 00:27:21,120
So, we've always had changes,
320
00:27:21,120 --> 00:27:25,680
but we're talking about changes over 10,000 years, in those cases.
321
00:27:25,680 --> 00:27:29,840
But we're now seeing is the equivalent in a few decades.
322
00:27:29,840 --> 00:27:32,960
And that, of course, is stretching life's capacity to keep up.
323
00:27:39,480 --> 00:27:44,240
Organisms, ecosystems are falling behind as the world changes,
324
00:27:44,240 --> 00:27:47,800
faster than it has in this enormous amount of time.
325
00:27:53,040 --> 00:27:58,000
It's been shown here that a rise of just two degrees centigrade
326
00:27:58,000 --> 00:28:01,120
will turn a healthy reef into a decimated one.
327
00:28:02,440 --> 00:28:06,120
And such a rise will almost certainly happen in these seas
328
00:28:06,120 --> 00:28:09,040
if we continue to do what we are doing.
329
00:28:19,480 --> 00:28:21,800
As Ove's tests suggest,
330
00:28:21,800 --> 00:28:24,440
this man-made problem has reached the point
331
00:28:24,440 --> 00:28:26,880
where it needs a man-made solution.
332
00:28:31,000 --> 00:28:33,160
I'm returning to mainland Australia
333
00:28:33,160 --> 00:28:36,080
to meet the scientists who are approaching this problem
334
00:28:36,080 --> 00:28:37,920
in a radically new way.
335
00:28:39,960 --> 00:28:44,240
The Australian Institute of Marine Science, AIMS,
336
00:28:44,240 --> 00:28:47,760
is based in northeast Queensland, right on the coast.
337
00:28:51,000 --> 00:28:55,520
Here, pioneering research is pushing the boundaries of coral science.
338
00:29:00,800 --> 00:29:04,680
Over three million litres of filtered seawater
339
00:29:04,680 --> 00:29:07,360
are pumped through these tanks every day.
340
00:29:08,360 --> 00:29:11,800
So, it's possible for scientists to study the minute
341
00:29:11,800 --> 00:29:16,600
and often very complex changes that can affect coral's health.
342
00:29:20,280 --> 00:29:22,800
So, here, they're also conducting research
343
00:29:22,800 --> 00:29:25,200
to see whether it might not be possible
344
00:29:25,200 --> 00:29:29,480
to devise techniques of restoring damaged reefs back to health.
345
00:29:31,560 --> 00:29:35,800
In these tanks, they can simulate the exact conditions of the reef.
346
00:29:37,640 --> 00:29:40,560
They've been so successful that remarkably,
347
00:29:40,560 --> 00:29:44,320
the corals respond to the same astronomic and seasonal rhythms
348
00:29:44,320 --> 00:29:46,000
as those out in the ocean.
349
00:29:49,760 --> 00:29:53,800
And that is proving useful for one particular experiment.
350
00:29:56,280 --> 00:29:59,840
Corals are usually able to adapt to changing circumstances,
351
00:29:59,840 --> 00:30:01,160
given enough time.
352
00:30:05,920 --> 00:30:09,400
And that is partly due to the way they reproduce.
353
00:30:12,640 --> 00:30:14,800
After the first full moon in October,
354
00:30:14,800 --> 00:30:18,080
the great synchronised coral spawning event begins.
355
00:30:38,960 --> 00:30:42,480
It's a wonderful, annual rejuvenation.
356
00:30:48,920 --> 00:30:53,400
Hundreds of species release sperm and eggs into the ocean.
357
00:30:57,000 --> 00:31:01,080
Just as pollen from plants is blown far and wide by the wind,
358
00:31:01,080 --> 00:31:04,680
so coral spawn is swept away by the ocean currents.
359
00:31:07,560 --> 00:31:10,920
And at the same time, under the same moonlight,
360
00:31:10,920 --> 00:31:14,920
the corals will spawn here in the laboratory tanks.
361
00:31:19,160 --> 00:31:22,960
Using red light, so as not to disturb the process,
362
00:31:22,960 --> 00:31:25,480
scientists wait for the moment of release.
363
00:31:39,760 --> 00:31:41,360
And when it finally happens,
364
00:31:41,360 --> 00:31:44,600
they move fast to collect the sperm and the eggs.
365
00:31:49,280 --> 00:31:52,560
It's their one chance to get all the samples they need
366
00:31:52,560 --> 00:31:54,480
for a year's worth of research.
367
00:31:57,680 --> 00:32:00,560
But what exactly are they planning to do with them?
368
00:32:03,960 --> 00:32:08,560
Here, Dr Madeleine van Oppen has been selectively breeding them,
369
00:32:08,560 --> 00:32:13,120
using much the same techniques that we've used to produce crops on land
370
00:32:13,120 --> 00:32:16,320
that are resistant to drought and disease.
371
00:32:16,320 --> 00:32:18,840
It's the first time that selective breeding
372
00:32:18,840 --> 00:32:21,240
has been used in marine conservation.
373
00:32:25,280 --> 00:32:27,600
They release their sperm and eggs in bundles
374
00:32:27,600 --> 00:32:30,600
and those bundles float to the surface of the tank.
375
00:32:30,600 --> 00:32:34,360
We then agitate that to separate the eggs from the sperm.
376
00:32:37,360 --> 00:32:38,880
And we use that to set up
377
00:32:38,880 --> 00:32:41,960
our specific in vitro processes, basically.
378
00:32:45,840 --> 00:32:48,080
In the ocean, there is the potential
379
00:32:48,080 --> 00:32:51,280
for different species of coral to breed with each other.
380
00:32:52,480 --> 00:32:54,440
So, here, scientists wonder
381
00:32:54,440 --> 00:32:57,640
if you might be able to produce a new kind of coral
382
00:32:57,640 --> 00:33:01,320
that proves more successful in the changing waters of the reef.
383
00:33:03,000 --> 00:33:05,520
The problem that corals are facing now is that
384
00:33:05,520 --> 00:33:08,280
the change of the environment is extremely fast -
385
00:33:08,280 --> 00:33:10,080
much faster than ever recorded -
386
00:33:10,080 --> 00:33:12,360
so we need to help them a little bit in the lab.
387
00:33:12,360 --> 00:33:16,080
We need to speed up those natural processes of evolution.
388
00:33:18,400 --> 00:33:23,360
Van Oppen's aim is to use selective breeding to produce strains of coral
389
00:33:23,360 --> 00:33:27,240
that are able to withstand the worst effects of climate change...
390
00:33:29,560 --> 00:33:34,840
..and to use them to bring life back to worst-affected part of the reef.
391
00:33:37,120 --> 00:33:39,120
Maybe in five years or so,
392
00:33:39,120 --> 00:33:42,200
we will be allowed to place those corals
393
00:33:42,200 --> 00:33:45,320
onto a real reef, a disturbed reef -
394
00:33:45,320 --> 00:33:48,000
and test it and these selectively-bred corals
395
00:33:48,000 --> 00:33:50,680
will be able to restore that reef faster.
396
00:33:51,880 --> 00:33:55,040
And you have to realise, this is really a last resort option.
397
00:33:55,040 --> 00:33:58,800
We wouldn't want to do that if the reef is able to restore itself.
398
00:34:04,160 --> 00:34:08,000
But is there a chance that the reef, damaged by our activities,
399
00:34:08,000 --> 00:34:10,720
could restore itself without our help?
400
00:34:13,240 --> 00:34:15,640
Well, we now think that there may be clues
401
00:34:15,640 --> 00:34:18,680
in the reef's most distant and mysterious regions.
402
00:34:25,920 --> 00:34:28,560
There are still parts of the Great Barrier Reef
403
00:34:28,560 --> 00:34:31,200
that are virtually unexplored.
404
00:34:31,200 --> 00:34:35,480
But today, we have got remarkable new underwater vessels,
405
00:34:35,480 --> 00:34:38,400
like this submersible, that can take us to places
406
00:34:38,400 --> 00:34:42,800
where no unprotected human being could possibly go.
407
00:34:42,800 --> 00:34:47,040
What they will find down there, nobody knows.
408
00:34:47,040 --> 00:34:49,320
But I'm lucky enough to be one of those
409
00:34:49,320 --> 00:34:51,800
who's about to go down to find out.
410
00:34:54,360 --> 00:34:56,160
At the outer edge of the reef,
411
00:34:56,160 --> 00:35:01,440
the continental shelf plunges down over 2,000 metres to the seafloor.
412
00:35:05,800 --> 00:35:09,280
The Alucia has brought us over the edge of the drop-off,
413
00:35:09,280 --> 00:35:12,000
90 miles out into the Coral Sea...
414
00:35:15,360 --> 00:35:17,600
..out to Osprey Reef.
415
00:35:19,920 --> 00:35:23,960
Here at Osprey, this sheer vertical drop of the seafloor
416
00:35:23,960 --> 00:35:26,960
enables us to see corals at a variety of depths.
417
00:35:28,480 --> 00:35:31,440
Between 100 and 150 metres down,
418
00:35:31,440 --> 00:35:33,760
daylight is reduced to a glimmer.
419
00:35:33,760 --> 00:35:36,840
This is the mesophotic zone.
420
00:35:36,840 --> 00:35:40,280
Here, a mysterious community of corals is thriving,
421
00:35:40,280 --> 00:35:43,360
despite the damage being done to the reef above.
422
00:35:43,360 --> 00:35:46,240
The Great Barrier Reef, it's a marvel beyond marvels.
423
00:35:46,240 --> 00:35:51,480
It's a million species living in this symbiotic tangle,
424
00:35:51,480 --> 00:35:53,040
half of which we don't know.
425
00:35:53,040 --> 00:35:55,600
I mean, when you get to mesophotic depths,
426
00:35:55,600 --> 00:35:58,080
we know very few of the species down there.
427
00:35:58,080 --> 00:36:01,560
It literally is one of the last frontiers of biology,
428
00:36:01,560 --> 00:36:03,160
to understand this system.
429
00:36:06,520 --> 00:36:09,760
Scientists are now beginning to wonder if these corals
430
00:36:09,760 --> 00:36:14,000
might have the potential to restore the damaged parts of the reef.
431
00:36:15,280 --> 00:36:17,480
- RADIO:
- '..Down about 100 metres...'
432
00:36:23,440 --> 00:36:25,400
Our state-of-the-art submersible
433
00:36:25,400 --> 00:36:29,280
is going to take me to see these deep corals for myself
434
00:36:29,280 --> 00:36:31,040
and even bring back a sample.
435
00:36:36,280 --> 00:36:38,320
Nadir in position.
436
00:36:38,320 --> 00:36:40,440
Are we clear to vent?
437
00:36:40,440 --> 00:36:43,360
You are clear to vent, clear to vent.
438
00:36:43,360 --> 00:36:45,000
Roger. Venting now.
439
00:36:57,360 --> 00:37:00,800
We are descending into the twilight zone.
440
00:37:07,840 --> 00:37:10,440
As we drop down the face of the reef,
441
00:37:10,440 --> 00:37:12,560
the light begins to dim.
442
00:37:21,040 --> 00:37:23,360
At about 100 metres,
443
00:37:23,360 --> 00:37:26,440
we enter the mesophotic zone.
444
00:37:26,440 --> 00:37:29,560
"Mesophotic" literally means "middle light".
445
00:37:32,040 --> 00:37:35,320
The corals here are beginning to look very different.
446
00:37:37,760 --> 00:37:40,360
Despite the apparent lack of light down here,
447
00:37:40,360 --> 00:37:44,000
there's still enough for some corals to photosynthesise,
448
00:37:44,000 --> 00:37:46,960
just like their relations closer to the surface.
449
00:37:46,960 --> 00:37:50,760
And to do that, they've formed these flat, broad plates
450
00:37:50,760 --> 00:37:53,200
to collect what little light there is.
451
00:37:57,800 --> 00:38:02,400
Mesophotic corals lie mostly out of reach of cyclones and bleaching.
452
00:38:04,800 --> 00:38:08,000
So, one of the big questions facing scientists is,
453
00:38:08,000 --> 00:38:13,200
could these deeper corals naturally repopulate the damaged reefs above?
454
00:38:24,440 --> 00:38:27,960
We've now passed beyond the mesophotic zone.
455
00:38:31,120 --> 00:38:33,640
The light begins to disappear completely
456
00:38:33,640 --> 00:38:36,240
and the reef changes again.
457
00:38:47,920 --> 00:38:50,960
Most of the light that filters down from above
458
00:38:50,960 --> 00:38:53,840
comes from the blue end of the spectrum,
459
00:38:53,840 --> 00:38:58,280
so the rock surface ahead of me looks very dull.
460
00:38:58,280 --> 00:39:01,560
But turn on the lights and it looks very different.
461
00:39:25,720 --> 00:39:27,720
Despite their remoteness,
462
00:39:27,720 --> 00:39:30,680
these strange relatives of reef-building corals
463
00:39:30,680 --> 00:39:33,080
are still part of the great reef system.
464
00:39:35,080 --> 00:39:38,960
To understand how they're connected, we need to study them closely.
465
00:39:41,080 --> 00:39:44,920
So, this seems an excellent place to collect a sample.
466
00:39:47,280 --> 00:39:51,800
But manoeuvring our eight-tonne submersible close to the rock face
467
00:39:51,800 --> 00:39:53,440
is a delicate operation.
468
00:40:12,400 --> 00:40:14,200
Oh, that's great.
469
00:40:22,800 --> 00:40:26,000
The chances are that this could well be a species
470
00:40:26,000 --> 00:40:28,000
that no-one has ever seen before.
471
00:40:31,440 --> 00:40:34,240
But things don't go quite to plan.
472
00:40:36,960 --> 00:40:39,720
- Oh, no!
- We're going to have to go and fetch that.
473
00:40:52,680 --> 00:40:54,120
There it is.
474
00:41:08,120 --> 00:41:09,560
Oh, terrific!
475
00:41:14,160 --> 00:41:15,720
Success!
476
00:41:25,360 --> 00:41:28,560
As we descend past the 200 metre mark,
477
00:41:28,560 --> 00:41:32,200
the coral finally begins to disappear altogether.
478
00:41:37,640 --> 00:41:39,760
Surface, surface, Nadir.
479
00:41:39,760 --> 00:41:44,200
My depth now, 300 metres. Over.
480
00:41:45,480 --> 00:41:50,160
At this depth, the pressure bearing down on the submersible's sphere
481
00:41:50,160 --> 00:41:53,000
is more than 30 times that at the surface.
482
00:41:55,040 --> 00:41:59,240
That's an incredible 450 pounds per square inch.
483
00:42:03,480 --> 00:42:06,680
Here, there's a sediment that is drifting down from above,
484
00:42:06,680 --> 00:42:09,240
cloaking the surface of the reef.
485
00:42:09,240 --> 00:42:11,920
That means it's very difficult for any organism
486
00:42:11,920 --> 00:42:16,280
to get a hold of the rock, because it's continually being swept down.
487
00:42:16,280 --> 00:42:21,920
The sediment itself is the result of the erosion of the coral skeletons from high above,
488
00:42:21,920 --> 00:42:25,240
but also from the remains of coral
489
00:42:25,240 --> 00:42:28,360
that parrot fish have munched and excreted
490
00:42:28,360 --> 00:42:30,880
and it's slowly drifting down here.
491
00:42:30,880 --> 00:42:34,280
So, this is so deep, it's almost barren.
492
00:42:44,480 --> 00:42:46,200
But not quite.
493
00:42:48,760 --> 00:42:51,480
At almost the deepest point of our dive,
494
00:42:51,480 --> 00:42:53,440
something pays us a visit.
495
00:42:56,760 --> 00:42:59,840
There's a fish to your right, David. On your shoulder.
496
00:42:59,840 --> 00:43:01,360
Look at this!
497
00:43:07,000 --> 00:43:09,520
It's a deep-water grouper.
498
00:43:09,520 --> 00:43:13,720
No-one has ever seen them up close like this, at this depth.
499
00:43:21,200 --> 00:43:24,840
'It appears to find the sub and its occupants fascinating.'
500
00:43:27,040 --> 00:43:30,360
And he's big, this boy. He must be...
501
00:43:32,600 --> 00:43:35,720
..four, five feet long - a couple of metres, almost.
502
00:43:38,520 --> 00:43:39,680
Hello.
503
00:43:39,680 --> 00:43:41,040
Oh, gosh!
504
00:43:45,800 --> 00:43:49,200
And why he is down here, what he's looking for - who knows?
505
00:43:56,960 --> 00:43:58,160
He's going up.
506
00:44:00,000 --> 00:44:01,320
So are we.
507
00:44:11,600 --> 00:44:16,320
As we ascend, light and colour returns to the reef around us.
508
00:44:58,400 --> 00:45:02,240
'Our on-board reef scientist, Professor Justin Marshall,
509
00:45:02,240 --> 00:45:05,840
'is on hand to retrieve the sample we gathered in the darkness.'
510
00:45:05,840 --> 00:45:08,440
- What do you reckon?
- Well, it's fantastic.
511
00:45:08,440 --> 00:45:12,320
This is one of the deepest samples ever from Osprey Reef.
512
00:45:12,320 --> 00:45:14,840
- It's wonderful.
- Will it survive? Will it still live?
513
00:45:14,840 --> 00:45:17,280
It will still live and we'll take samples back
514
00:45:17,280 --> 00:45:20,720
- to the University of Queensland and work on it there.
- Great.
515
00:45:22,600 --> 00:45:25,800
In fact, they think this coral has never been reported
516
00:45:25,800 --> 00:45:29,120
in this part of the world before and may be new to science.
517
00:45:33,720 --> 00:45:36,520
We are a long way off from having a solution
518
00:45:36,520 --> 00:45:39,680
to the threats which now face the Great Barrier Reef.
519
00:45:41,720 --> 00:45:43,600
But in these deep water samples
520
00:45:43,600 --> 00:45:46,680
and in the scientists' experimental tanks,
521
00:45:46,680 --> 00:45:48,600
there is a small glimmer of hope.
522
00:45:51,200 --> 00:45:53,520
But time is not on our side -...
523
00:45:57,520 --> 00:46:01,280
..an opinion shared by many of the scientists I've met along the way.
524
00:46:05,880 --> 00:46:08,360
Are you fearful for the future of the reef?
525
00:46:08,360 --> 00:46:10,000
There will be change, for sure.
526
00:46:10,000 --> 00:46:14,800
I mean, we're seeing change within our own human lives' timescales now.
527
00:46:14,800 --> 00:46:16,600
And what's your prediction about
528
00:46:16,600 --> 00:46:19,800
what it's going to look like in another hundred years?
529
00:46:19,800 --> 00:46:21,720
The sea levels will be higher.
530
00:46:21,720 --> 00:46:24,520
We want to know - as a scientist, we want to know
531
00:46:24,520 --> 00:46:26,920
how the Great Barrier Reef will respond.
532
00:46:26,920 --> 00:46:30,640
Whether it has the resilience to bounce back
533
00:46:30,640 --> 00:46:35,240
with the future changes to the climate remains to be seen.
534
00:46:39,880 --> 00:46:41,480
Here on the Great Barrier Reef,
535
00:46:41,480 --> 00:46:45,160
we've lost about 50% of the coral since the early 1980s.
536
00:46:47,280 --> 00:46:51,480
Coral provides a habitat for over a million species.
537
00:46:51,480 --> 00:46:54,720
This is such a fundamental part of our oceans
538
00:46:54,720 --> 00:46:57,640
and the fact that it's going to disappear on our watch,
539
00:46:57,640 --> 00:46:58,840
it's incredible.
540
00:47:16,440 --> 00:47:20,160
When the Great Barrier Reef starts to go seriously backwards,
541
00:47:20,160 --> 00:47:21,960
the next generation is going to say,
542
00:47:21,960 --> 00:47:25,760
"Why didn't you guys do something about it when you had a chance?"
543
00:47:25,760 --> 00:47:27,720
And well may they ask that
544
00:47:27,720 --> 00:47:30,840
because we're not doing what we should be doing
545
00:47:30,840 --> 00:47:32,880
and we're going to pay the price.
546
00:47:51,000 --> 00:47:54,400
The Great Barrier Reef is in grave danger.
547
00:47:54,400 --> 00:47:57,560
The twin perils brought by climate change
548
00:47:57,560 --> 00:48:02,120
and increase in the temperature of the ocean and in its acidity
549
00:48:02,120 --> 00:48:05,080
threaten its very existence.
550
00:48:05,080 --> 00:48:08,400
If they continue to rise at the present rate,
551
00:48:08,400 --> 00:48:11,960
the reefs will be gone within decades.
552
00:48:11,960 --> 00:48:15,720
And that would be a global catastrophe.
553
00:48:18,480 --> 00:48:22,440
About one quarter of the species of fish in the world
554
00:48:22,440 --> 00:48:25,960
spend some part of their lives in the reefs.
555
00:48:25,960 --> 00:48:29,560
If the reefs go, the fish will also disappear.
556
00:48:30,800 --> 00:48:33,400
And that could affect the livelihood
557
00:48:33,400 --> 00:48:36,960
and diet of human communities worldwide.
558
00:48:38,440 --> 00:48:42,440
But there's surely another reason why we should protect the reefs.
559
00:48:42,440 --> 00:48:46,680
They are among this planet's richest, most complex
560
00:48:46,680 --> 00:48:49,200
and most beautiful ecosystems.
561
00:49:05,880 --> 00:49:10,600
Do we really care so little about the Earth on which we live
562
00:49:10,600 --> 00:49:14,560
that we don't wish to protect one of its greatest wonders
563
00:49:14,560 --> 00:49:17,640
from the consequences of our behaviour?
564
00:49:42,440 --> 00:49:45,160
For this series, the production team were determined
565
00:49:45,160 --> 00:49:47,960
to show the Barrier Reef in a new way,
566
00:49:47,960 --> 00:49:50,800
by filming in some of its most remote areas...
567
00:49:53,280 --> 00:49:54,920
..and allowing me to meet
568
00:49:54,920 --> 00:49:58,080
some of its more unusual and surprising inhabitants.
569
00:50:00,440 --> 00:50:03,800
'This took us out onto the top of Heron Island's reef,
570
00:50:03,800 --> 00:50:05,960
'which is only exposed at low tide.
571
00:50:09,520 --> 00:50:12,360
'But we had to tread carefully, accompanied by guides,
572
00:50:12,360 --> 00:50:15,560
'to ensure that we didn't damage any of the coral.'
573
00:50:16,840 --> 00:50:19,040
Anybody who's coming on here, it's weird at first,
574
00:50:19,040 --> 00:50:22,400
but just try and walk on the dead coral - the concrete stuff.
575
00:50:22,400 --> 00:50:24,880
'We were there to film an elusive creature
576
00:50:24,880 --> 00:50:28,640
'that feeds in this special habitat when the tide is out -
577
00:50:28,640 --> 00:50:30,160
'the epaulette shark.'
578
00:50:31,360 --> 00:50:34,920
There's one with a tail - the first one is there.
579
00:50:34,920 --> 00:50:37,520
- Just gone.
- It's gone under there.
580
00:50:39,640 --> 00:50:44,680
'Professor Gillian Renshaw has been studying these sharks for 20 years.'
581
00:50:44,680 --> 00:50:46,800
It's very hard to see the epaulettes
582
00:50:46,800 --> 00:50:50,040
because they're cryptically coloured and blend in very well
583
00:50:50,040 --> 00:50:53,800
with the fingers of coral that are rising out of the reef platform.
584
00:50:55,240 --> 00:50:58,040
'It's a challenging location, not least because
585
00:50:58,040 --> 00:51:00,920
'it's only accessible for short periods of time.'
586
00:51:03,080 --> 00:51:05,360
We've got probably about 40 minutes
587
00:51:05,360 --> 00:51:07,440
to get all of the shots that we need,
588
00:51:07,440 --> 00:51:10,840
so I shouldn't really be talking to you, we should be getting this.
589
00:51:10,840 --> 00:51:15,000
- OK, quiet please!
- Camera's rolling. And action, David.
590
00:51:15,000 --> 00:51:18,240
The epaulette shark remains on the reef,
591
00:51:18,240 --> 00:51:20,640
even when the tide goes out.
592
00:51:21,880 --> 00:51:23,880
Of course, with so little water,
593
00:51:23,880 --> 00:51:27,080
it doesn't get as much oxygen as it requires normally, but...
594
00:51:29,040 --> 00:51:30,760
'Although my piece is done,
595
00:51:30,760 --> 00:51:34,160
'the team must now film the shark's unique walking behaviour.'
596
00:51:34,160 --> 00:51:36,880
The water is literally pouring in around the equipment
597
00:51:36,880 --> 00:51:38,560
and over our feet.
598
00:51:38,560 --> 00:51:41,200
We've got about 10 to 15 minutes to get this sequence finished
599
00:51:41,200 --> 00:51:43,680
and get back in the boats before we're literally cut off
600
00:51:43,680 --> 00:51:45,760
and we can't get back to the boats.
601
00:51:47,840 --> 00:51:50,320
'The tide creeps in around us.'
602
00:51:55,880 --> 00:51:58,200
He's walking beautifully, now. Look at that.
603
00:52:00,280 --> 00:52:03,640
Let's try and get it in the water a bit.
604
00:52:03,640 --> 00:52:06,600
Really nice performance from the epaulette shark.
605
00:52:08,480 --> 00:52:11,240
'Now, it's a race against time to get off the reef.'
606
00:52:12,320 --> 00:52:13,800
Are we ready for the boat, now?
607
00:52:13,800 --> 00:52:16,280
Geraldine, can we get David on, please?
608
00:52:21,360 --> 00:52:23,800
Yeah, looked stunning. Worth the stress.
609
00:52:25,560 --> 00:52:28,720
'This trip took us from the very top of the reef
610
00:52:28,720 --> 00:52:30,800
'down almost to its bottom...
611
00:52:31,920 --> 00:52:34,720
'..for our most ambitious sequence of the series -...
612
00:52:36,040 --> 00:52:38,560
'..to attempt the deepest dive in this area
613
00:52:38,560 --> 00:52:42,320
'and collect a sample of the mysterious coral that survives there.
614
00:52:43,720 --> 00:52:46,160
'And it's down to cameraman Paul Williams
615
00:52:46,160 --> 00:52:48,480
'to film our mission single-handedly.'
616
00:52:50,400 --> 00:52:52,200
I'm on my own down there.
617
00:52:52,200 --> 00:52:54,240
I've gone over it and over it again in my mind,
618
00:52:54,240 --> 00:52:57,040
about what we're trying to do and how we're going to do it,
619
00:52:57,040 --> 00:52:59,040
so I think I've got it locked in.
620
00:52:59,040 --> 00:53:01,120
I hope haven't forgotten anything.
621
00:53:01,120 --> 00:53:03,200
'It's something of a squeeze in the sub,
622
00:53:03,200 --> 00:53:06,160
'with all of Paul's filming equipment.'
623
00:53:06,160 --> 00:53:08,800
Do you mind if I just give you that for a moment?
624
00:53:09,880 --> 00:53:12,520
'But our third crew member is essential.
625
00:53:12,520 --> 00:53:14,920
'He's the pilot, Buck Taylor.'
626
00:53:19,120 --> 00:53:22,240
I'm sitting with a big camera on my shoulder
627
00:53:22,240 --> 00:53:25,280
and two other cameras, which were outside the sub,
628
00:53:25,280 --> 00:53:28,480
controlled by laptops which were both on my lap.
629
00:53:32,160 --> 00:53:35,200
The sound kit was under Buck's feet.
630
00:53:35,200 --> 00:53:36,440
It was tight in there.
631
00:53:44,720 --> 00:53:46,080
David, do you mind?
632
00:53:46,080 --> 00:53:49,120
- Would you get your towel and just give that a little wipe there?
- Yup.
633
00:53:49,120 --> 00:53:50,920
Thank you, sir.
634
00:53:53,800 --> 00:53:55,920
'For the first part of the dive,
635
00:53:55,920 --> 00:53:58,720
'underwater cameramen filmed the sub's descent.
636
00:53:59,800 --> 00:54:02,960
'But at about 60 metres, they reached their limit.
637
00:54:05,040 --> 00:54:07,120
'It's only possible to venture further
638
00:54:07,120 --> 00:54:09,560
'within the protection of the submarine.
639
00:54:10,760 --> 00:54:14,240
'As we enter the mesophotic zone, around 100 metres down,
640
00:54:14,240 --> 00:54:15,840
'we're on our own.
641
00:54:20,120 --> 00:54:22,680
'To get the best shots of the reef beyond,
642
00:54:22,680 --> 00:54:25,640
'Paul requires all of Buck's skill as a pilot.'
643
00:54:26,800 --> 00:54:29,440
Do you want to try some other light options?
644
00:54:29,440 --> 00:54:32,000
- What have you got?
- I can give you that.
645
00:54:32,000 --> 00:54:35,800
Yeah, put the higher ones on, take the lower ones off.
646
00:54:35,800 --> 00:54:39,960
- How's that?
- Yes. Actually, that looks better.
- Isn't it lovely?
647
00:54:39,960 --> 00:54:42,480
- Probably full of nooks and crannies.
- Yeah.
648
00:54:42,480 --> 00:54:44,240
Buck, the sub driver, was brilliant.
649
00:54:44,240 --> 00:54:46,000
He'd find a drift in the currents
650
00:54:46,000 --> 00:54:48,040
and then we'd just drift across the coral.
651
00:54:48,040 --> 00:54:50,360
What's nice is, I can actually see the wall.
652
00:54:50,360 --> 00:54:53,360
- That's a very good angle for me.
- Is it?
- Yeah.
653
00:54:53,360 --> 00:54:56,800
So, just let us drift a tiny bit to starboard.
654
00:54:56,800 --> 00:54:58,640
And...action, David.
655
00:54:58,640 --> 00:55:04,320
This wall of rock ahead of me is actually the flank of Osprey Reef -
656
00:55:04,320 --> 00:55:07,080
an oasis for life.
657
00:55:07,080 --> 00:55:09,720
'But we weren't down here just to look.
658
00:55:09,720 --> 00:55:13,600
'We also wanted to collect samples for deep reef scientists...
659
00:55:15,480 --> 00:55:18,400
'..and that proved easier said than done.'
660
00:55:18,400 --> 00:55:21,480
- Oh, no!
- We have to go and fetch that.
661
00:55:21,480 --> 00:55:22,880
We'll take that on film.
662
00:55:25,200 --> 00:55:28,000
'As we descended beyond 250 metres,
663
00:55:28,000 --> 00:55:31,600
'we entered a landscape rarely seen with the naked eye.
664
00:55:33,760 --> 00:55:37,280
'It was the perfect opportunity simply to explore.'
665
00:55:38,560 --> 00:55:40,920
This is the first time that manned submersibles
666
00:55:40,920 --> 00:55:42,600
have worked at this depth
667
00:55:42,600 --> 00:55:45,320
and it gives one the ability to look and observe
668
00:55:45,320 --> 00:55:48,280
and just do curiosity-driven research.
669
00:55:48,280 --> 00:55:50,120
It's fantastic.
670
00:55:50,120 --> 00:55:52,960
The visibility down here spectacular, isn't it?
671
00:55:52,960 --> 00:55:55,200
It's absolutely pure, yeah.
672
00:55:55,200 --> 00:55:58,400
There were many times when I had to take my eye away from the eyepiece
673
00:55:58,400 --> 00:56:01,320
because I just had to look with my own eyes,
674
00:56:01,320 --> 00:56:04,000
so it goes into the brain properly
675
00:56:04,000 --> 00:56:05,680
in the right perspective.
676
00:56:07,360 --> 00:56:09,640
'Soon, we reached our target depth.'
677
00:56:12,680 --> 00:56:14,200
There it is. 300.
678
00:56:15,760 --> 00:56:21,320
Nobody before has ever been as deep as this on the Great Barrier Reef.
679
00:56:21,320 --> 00:56:22,840
I like it.
680
00:56:22,840 --> 00:56:25,480
LAUGHTER
681
00:56:25,480 --> 00:56:28,240
So, it hasn't even come up on here - 290 metres,
682
00:56:28,240 --> 00:56:31,160
but we've heard that they've just reached 300 metres.
683
00:56:31,160 --> 00:56:34,800
Another thing to add to the things that David's done on this planet.
684
00:56:34,800 --> 00:56:37,080
'The purpose of our record-breaking trip
685
00:56:37,080 --> 00:56:40,880
'was to raise awareness of the reef's fragility.
686
00:56:40,880 --> 00:56:44,200
'Fortunately, while production continued on the series,
687
00:56:44,200 --> 00:56:47,080
'the dive caught the attention of a president.'
688
00:56:48,160 --> 00:56:52,600
- Mr President.
- When I heard that you had gone down,
689
00:56:52,600 --> 00:56:55,400
you dove into the Great Barrier Reef again...
690
00:56:56,880 --> 00:56:58,800
..60 years after the first time you did it?
691
00:56:58,800 --> 00:57:00,480
- Yes.
- That impressed me.
692
00:57:00,480 --> 00:57:02,800
Ah, but I was in a sub.
693
00:57:02,800 --> 00:57:05,440
I mean, I was in a very, very remarkable research sub
694
00:57:05,440 --> 00:57:07,760
and we went down to over 300 metres.
695
00:57:07,760 --> 00:57:10,000
Oh, so you went really deep.
696
00:57:10,000 --> 00:57:11,920
And that was just mind-blowing.
697
00:57:13,120 --> 00:57:16,800
The deep dive proved a truly memorable moment for me
698
00:57:16,800 --> 00:57:19,880
and allowed us the unique opportunity of revealing
699
00:57:19,880 --> 00:57:23,520
a part of this great reef that has never before been seen.
59127
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.