Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:10,000 --> 00:00:12,520
(HOOTING AND PIPING)
2
00:00:12,560 --> 00:00:13,640
(HONKING)
3
00:00:13,680 --> 00:00:16,760
DAVID ATTENBOROUGH: The natural
world is filled with sound.
4
00:00:16,800 --> 00:00:19,440
(CLICKING, THUNDER CRASHING)
5
00:00:19,480 --> 00:00:21,360
(CLUCKING)
6
00:00:21,400 --> 00:00:23,040
(BRAYING)
7
00:00:23,080 --> 00:00:24,200
(GROWLING)
8
00:00:25,120 --> 00:00:28,880
But, so far, we've been hearing
only part of it.
9
00:00:31,120 --> 00:00:34,360
Some animals call
even before they enter the world.
10
00:00:34,400 --> 00:00:36,880
(SQUEAKING, SOFT HONKING)
11
00:00:36,920 --> 00:00:37,960
(RATTLING SOUND)
12
00:00:40,320 --> 00:00:43,280
Others use sound to communicate
with their siblings.
13
00:00:43,320 --> 00:00:45,000
(CHATTERING)
14
00:00:48,520 --> 00:00:49,720
Or call to their parents.
15
00:00:49,760 --> 00:00:51,600
(GROUP SQUAWKING)
16
00:00:51,640 --> 00:00:55,720
Using the most advanced
audio technology,
17
00:00:55,760 --> 00:00:57,600
we can listen to them all...
(DRAWN-OUT WHINE)
18
00:00:59,280 --> 00:01:02,360
..to reveal how baby animals
use sound to stay alive...
19
00:01:02,400 --> 00:01:03,400
(WHINES)
20
00:01:04,360 --> 00:01:07,160
..in a world where the odds
are stacked against them.
21
00:01:07,200 --> 00:01:08,960
(HOWLING)
22
00:01:16,080 --> 00:01:18,360
(ANIMATED BIRDSONG)
23
00:01:20,920 --> 00:01:23,240
The most perilous time
in an animal's life
24
00:01:24,039 --> 00:01:25,960
is at its very beginning.
25
00:01:29,360 --> 00:01:30,480
(CHUCKLES)
26
00:01:32,200 --> 00:01:34,479
These little cygnets are just
three days old.
27
00:01:41,680 --> 00:01:44,840
And at this stage of their lives,
and for some months to come,
28
00:01:44,880 --> 00:01:47,039
they are unable to fly.
29
00:01:48,520 --> 00:01:53,400
As a consequence, they are easy prey
for a gull or a fox.
30
00:01:56,200 --> 00:02:00,800
But there's just one thing
that is of extreme importance
31
00:02:00,840 --> 00:02:02,200
to their survival.
32
00:02:02,240 --> 00:02:04,160
And that...is sound.
33
00:02:04,200 --> 00:02:06,280
(CHIRPING)
34
00:02:17,280 --> 00:02:20,720
The Kalahari Desert
in southern Africa.
35
00:02:22,160 --> 00:02:24,800
(CHIRRUPING)
36
00:02:24,840 --> 00:02:27,760
This is the home of a kind of
burrowing mongoose...
37
00:02:29,600 --> 00:02:30,920
Meerkats.
38
00:02:30,960 --> 00:02:33,000
(HIGH-PITCHED CHIRPING
AND GRUNTING)
39
00:02:34,560 --> 00:02:37,520
This season's pups are taking
their first steps in the world
40
00:02:37,560 --> 00:02:39,920
outside their family's home.
41
00:02:45,040 --> 00:02:46,200
(CHATTERS)
42
00:02:49,000 --> 00:02:50,920
(SHORT SCREECHES)
43
00:02:55,040 --> 00:02:57,200
(SQUAWKS)
44
00:02:59,960 --> 00:03:03,400
In time, they will get to know
the sounds of everything
45
00:03:04,480 --> 00:03:06,800
that's going on around them.
46
00:03:07,800 --> 00:03:09,160
(FLIES BUZZING)
47
00:03:09,200 --> 00:03:10,240
(SNORTS)
48
00:03:10,280 --> 00:03:14,920
But just now, what they want
is breakfast.
49
00:03:15,680 --> 00:03:17,960
And to get it,
they must make themselves heard.
50
00:03:18,000 --> 00:03:19,480
(SQUEAKS)
51
00:03:20,600 --> 00:03:23,760
The smallest pup has an injured foot
52
00:03:23,800 --> 00:03:25,800
and keeping up with the rest is
a struggle.
53
00:03:30,280 --> 00:03:31,680
(HIGH-PITCHED GRUNTS)
54
00:03:35,079 --> 00:03:38,160
Once they emerge, meerkat pups
need more food
55
00:03:38,200 --> 00:03:40,840
than their own parents
can provide,
56
00:03:40,880 --> 00:03:44,680
so they must persuade other adults
to feed them.
57
00:03:44,720 --> 00:03:46,360
(PURRS)
58
00:03:51,600 --> 00:03:54,240
But in this harsh country,
59
00:03:54,280 --> 00:03:56,960
food isn't easy to find.
60
00:03:58,560 --> 00:04:02,120
Temperatures can reach over 45C,
61
00:04:02,160 --> 00:04:04,520
and most food is hidden underground.
62
00:04:07,400 --> 00:04:11,240
So a meerkat's life is dominated
by digging.
63
00:04:12,640 --> 00:04:15,280
They may have to shift
their entire body weight in sand
64
00:04:15,320 --> 00:04:18,800
to find just one mouthful to eat.
65
00:04:21,399 --> 00:04:24,320
After all this hard work,
the helpers can be more interested
66
00:04:24,360 --> 00:04:26,200
in feeding themselves than the pups.
67
00:04:26,240 --> 00:04:28,920
(RAPID PURRING)
68
00:04:33,600 --> 00:04:37,000
So the youngsters beg continuously.
69
00:04:37,040 --> 00:04:39,760
(SQUEAKING AND PURRING)
70
00:04:44,800 --> 00:04:47,600
The moment food is found,
71
00:04:47,640 --> 00:04:50,880
each pup switches to a high-pitched
begging call
72
00:04:50,920 --> 00:04:54,280
in an attempt to ensure that it,
and not its siblings,
73
00:04:54,320 --> 00:04:55,480
gets the mouthful.
74
00:04:55,520 --> 00:04:56,800
(ALL CHATTERING AND SQUEAKING)
75
00:05:01,760 --> 00:05:04,600
And those who make this begging call
more intensely
76
00:05:04,640 --> 00:05:06,880
get the food.
77
00:05:07,800 --> 00:05:12,800
The biggest pup is successful,
and the smallest misses out again...
78
00:05:14,240 --> 00:05:15,760
..and again.
79
00:05:20,400 --> 00:05:24,080
Staying close to an adult
increases the chances of being heard
80
00:05:24,120 --> 00:05:25,560
and being fed.
81
00:05:27,800 --> 00:05:31,040
But this brings its own hazards.
82
00:05:33,200 --> 00:05:36,640
(PUP SQUEAKS)
83
00:05:38,159 --> 00:05:40,480
Finally, the small one does get
a mouthful.
84
00:05:44,320 --> 00:05:47,520
But he takes a long time
to eat it...
85
00:05:51,840 --> 00:05:55,360
..and when he looks up,
everyone else has gone.
86
00:05:55,400 --> 00:05:56,800
(SOFT SQUEAK)
87
00:06:01,520 --> 00:06:04,480
If there's one thing more important
to a meerkat than food,
88
00:06:05,440 --> 00:06:06,960
it's family.
89
00:06:08,680 --> 00:06:12,880
Without their guidance, he wouldn't
last for long in this intense heat.
90
00:06:15,960 --> 00:06:17,080
(CHIRPS)
91
00:06:17,120 --> 00:06:18,640
He calls for help.
92
00:06:18,680 --> 00:06:20,920
(CHIRPS)
93
00:06:23,720 --> 00:06:25,040
(LONG CHIRP)
94
00:06:25,080 --> 00:06:27,040
Making such a noise, however,
has risks.
95
00:06:27,080 --> 00:06:28,200
(CHIRPS)
96
00:06:34,200 --> 00:06:35,800
(DISTANT CHIRP)
97
00:06:37,320 --> 00:06:39,080
At last an adult hears him.
98
00:06:39,960 --> 00:06:41,159
(SQUEAKING)
99
00:07:00,120 --> 00:07:04,200
But the heat and exhaustion
have taken their toll.
100
00:07:05,080 --> 00:07:06,600
It may be too late.
101
00:07:08,360 --> 00:07:11,680
His sister encourages him
to get back on his feet.
102
00:07:11,720 --> 00:07:14,320
(CHEEPING)
103
00:07:28,680 --> 00:07:32,760
Once again, the little meerkat
has been saved...by sound.
104
00:07:35,560 --> 00:07:38,920
(URGENT BARKING)
105
00:07:40,440 --> 00:07:45,240
As the pups grow, they will face
many new challenges...
106
00:07:47,159 --> 00:07:49,840
..including predators.
107
00:07:51,600 --> 00:07:54,880
Sound will be invaluable to help
them navigate these dangers.
108
00:07:54,920 --> 00:07:56,920
(CROAKING)
109
00:07:58,080 --> 00:08:02,400
But some baby animals use sound
before they even enter the world.
110
00:08:03,280 --> 00:08:04,880
(BIRDS HOOT AND PIPE)
111
00:08:06,360 --> 00:08:08,080
The swamps of South America.
112
00:08:12,320 --> 00:08:13,800
There is danger everywhere.
113
00:08:13,840 --> 00:08:16,480
(SNORTING)
114
00:08:20,240 --> 00:08:23,560
One vigilant mother here is
on guard.
115
00:08:25,560 --> 00:08:26,640
A caiman.
116
00:08:28,960 --> 00:08:32,360
Over two metres long and weighing
around 60 kilograms,
117
00:08:32,400 --> 00:08:36,840
she lives by ambushing prey
in these murky waters.
118
00:08:39,200 --> 00:08:41,559
On the bank, close to the river,
119
00:08:42,280 --> 00:08:43,480
there is a great mound.
120
00:08:47,920 --> 00:08:50,240
It's her nest.
121
00:08:55,200 --> 00:08:56,840
And inside, there are her eggs,
122
00:08:58,960 --> 00:09:00,840
30 or so of them.
123
00:09:05,720 --> 00:09:10,040
Her nest-guarding duties, however,
are coming to an end.
124
00:09:13,800 --> 00:09:16,040
The young, still within the eggs,
125
00:09:16,080 --> 00:09:18,760
are approaching one of the most
dangerous moments
126
00:09:18,800 --> 00:09:20,560
they will ever face.
127
00:09:20,600 --> 00:09:22,960
And they are squeaking.
128
00:09:24,200 --> 00:09:26,520
(PULSING SQUEAKS)
129
00:09:26,560 --> 00:09:30,040
Their chances of survival
will depend on these noises.
130
00:09:32,040 --> 00:09:36,280
We have a special camera
with 60 super-sensitive microphones
131
00:09:36,320 --> 00:09:39,960
which can show us which squeak
is coming from which egg.
132
00:09:40,000 --> 00:09:41,760
(SQUEAKING)
133
00:09:41,800 --> 00:09:44,480
(SQUEAKING)
134
00:09:46,520 --> 00:09:47,920
The first starts to hatch.
135
00:09:50,080 --> 00:09:52,240
(SQUEAKING)
136
00:09:52,280 --> 00:09:56,000
But the youngsters would stand
a much better chance of survival
137
00:09:56,040 --> 00:09:58,880
if they all hatched simultaneously.
138
00:09:58,920 --> 00:10:00,080
(VARIOUS TONES OF SQUEAKING)
139
00:10:00,880 --> 00:10:02,080
So they call to one another
140
00:10:02,120 --> 00:10:05,200
to indicate how close they are
to emerging.
141
00:10:06,640 --> 00:10:09,400
(SHORT GRUNTS AND SQUEAKS)
142
00:10:12,000 --> 00:10:14,400
It succeeds in struggling free
from the egg.
143
00:10:18,400 --> 00:10:20,120
But it has a problem.
144
00:10:20,160 --> 00:10:21,720
(BIRDS CHIRPING)
145
00:10:23,400 --> 00:10:26,120
The nest that once kept them
all safe...
146
00:10:27,640 --> 00:10:29,200
..now keeps them trapped.
147
00:10:29,240 --> 00:10:31,560
(GULPING SQUEAKS AND HONKS)
148
00:10:35,160 --> 00:10:38,080
The calls of the emerged
now encourage the others
149
00:10:38,120 --> 00:10:40,640
to break out of their eggs.
150
00:10:40,680 --> 00:10:42,960
(HONKS)
151
00:10:44,600 --> 00:10:48,440
But they still can't get out of
the nest without help.
152
00:10:51,880 --> 00:10:54,320
Individually,
they can barely be heard.
153
00:10:54,360 --> 00:10:56,160
(HONKS)
154
00:10:57,320 --> 00:11:01,160
But together they become loud enough
for their mother to hear them.
155
00:11:01,200 --> 00:11:04,400
(MANY HONKING SIMULTANEOUSLY)
156
00:11:04,440 --> 00:11:06,760
(CHORUS OF HONKS)
157
00:11:06,800 --> 00:11:10,640
She has been waiting for these
sounds for nearly 70 days.
158
00:11:11,800 --> 00:11:15,280
(ANIMATED HONKING)
159
00:11:21,040 --> 00:11:22,760
(HONKING)
160
00:11:24,760 --> 00:11:26,120
And she goes into action.
161
00:11:27,880 --> 00:11:30,720
(HATCHLINGS HONK AND CHITTER)
162
00:11:57,480 --> 00:12:00,120
One by one,
she picks her hatchlings up
163
00:12:00,160 --> 00:12:02,360
and takes them down to the water.
164
00:12:19,440 --> 00:12:23,240
The last to hatch
are sometimes forgotten.
165
00:12:24,800 --> 00:12:28,680
But with the nest fully opened,
they can now get out.
166
00:12:30,600 --> 00:12:33,440
But they have no idea
where their mother is.
167
00:12:35,080 --> 00:12:38,360
(HONK AND CHITTER)
Once again, they are saved by sound.
168
00:12:42,000 --> 00:12:44,840
They can recognise the voices
of their siblings
169
00:12:44,880 --> 00:12:46,840
and follow the sound to the water...
170
00:12:46,880 --> 00:12:49,760
where their mother
will guard them all.
171
00:12:50,560 --> 00:12:52,240
(CHITTERING)
172
00:12:53,880 --> 00:12:57,800
Sound has guided them on the first
and most hazardous journey
173
00:12:57,840 --> 00:12:59,000
of their lives.
174
00:13:02,880 --> 00:13:05,360
(CHITTERING)
175
00:13:16,640 --> 00:13:17,960
(CUCKOO CALLS)
176
00:13:18,000 --> 00:13:22,000
(SHEEP BLEATS, WOODPECKER TAPS,
WOOD PIGEON COOS)
177
00:13:22,040 --> 00:13:25,520
(BLACKBIRDS SING, BEES BUZZING)
178
00:13:25,560 --> 00:13:27,360
The sounds of an English spring.
179
00:13:28,200 --> 00:13:32,040
(BIRDSONG AND BUZZING)
180
00:13:37,080 --> 00:13:39,160
For many of the animals
that live here,
181
00:13:39,960 --> 00:13:42,080
they carry important messages.
182
00:13:44,080 --> 00:13:46,120
(BEE BUZZING)
183
00:13:48,000 --> 00:13:52,080
This bee has discovered that the
flowers are now producing nectar.
184
00:13:55,560 --> 00:13:57,480
She gathers all she can...
185
00:13:59,920 --> 00:14:02,920
and then flies back
with the good news.
186
00:14:02,960 --> 00:14:04,800
(BUZZES)
187
00:14:06,840 --> 00:14:09,920
Her colony has been inactive
during the colder months.
188
00:14:11,520 --> 00:14:15,280
But now the time has come
for action.
189
00:14:15,320 --> 00:14:17,560
(HIVE BUZZES)
190
00:14:26,000 --> 00:14:27,520
(AMPLIFIED BEATING SOUND)
191
00:14:28,680 --> 00:14:31,040
The forager conveys her news
192
00:14:31,080 --> 00:14:34,440
by repeatedly thumping her abdomen
on the comb.
193
00:14:34,480 --> 00:14:41,440
Bees, like many insects,
don't have ears,
194
00:14:43,320 --> 00:14:45,920
so they can't hear airborne sounds.
195
00:14:45,960 --> 00:14:49,000
(BEATING SOUNDS)
196
00:14:49,040 --> 00:14:51,280
(BUZZING)
197
00:14:52,040 --> 00:14:56,200
But they can feel the vibrations
she makes on the comb...
198
00:14:56,240 --> 00:14:59,560
(RAPID TAPPING)
199
00:14:59,600 --> 00:15:04,800
..detecting it with the sense organs
in their legs.
200
00:15:04,840 --> 00:15:06,640
(ECHOEY TAPS)
201
00:15:11,840 --> 00:15:14,440
And those that are still asleep
202
00:15:14,480 --> 00:15:18,760
are alerted by her signal that drums
directly into their body.
203
00:15:18,800 --> 00:15:21,000
(CONSTANT TAPPING)
204
00:15:27,520 --> 00:15:31,480
Eventually, the workers are roused
into action.
205
00:15:51,880 --> 00:15:55,240
Within days,
the hive's depleted stores
206
00:15:55,280 --> 00:15:58,400
are restocked with nectar
and pollen...
207
00:15:59,680 --> 00:16:03,960
..food that will fuel the production
of the next generation of bees.
208
00:16:11,520 --> 00:16:13,840
When a colony has grown so much
209
00:16:13,880 --> 00:16:17,640
that it contains
around 40,000 individuals,
210
00:16:17,680 --> 00:16:19,880
it prepares to swarm.
211
00:16:20,920 --> 00:16:26,040
But a new swarm will need a queen,
and the old queen has already left.
212
00:16:28,040 --> 00:16:30,280
There are several contenders
for the role
213
00:16:30,320 --> 00:16:33,680
who are developing in particularly
large cells.
214
00:16:35,800 --> 00:16:38,840
Tiny super-sensitive microphones
215
00:16:38,880 --> 00:16:41,480
enable us to hear
an extraordinary call,
216
00:16:41,520 --> 00:16:42,800
like the quacking of a duck.
217
00:16:42,840 --> 00:16:44,480
(REPEATED QUACKS)
218
00:16:50,720 --> 00:16:53,400
The unhatched queens are signalling
219
00:16:53,440 --> 00:16:55,480
that they're ready to emerge.
220
00:16:55,520 --> 00:16:56,840
(QUACK-LIKE CHORUS)
221
00:16:57,960 --> 00:17:01,200
The workers detect the vibrations
of these calls
222
00:17:01,240 --> 00:17:05,960
and in response they start
to release the first queen.
223
00:17:06,000 --> 00:17:07,079
(QUACKING)
224
00:17:11,200 --> 00:17:13,960
If two queens are released
at the same time,
225
00:17:14,000 --> 00:17:16,920
they will fight one another
to the death.
226
00:17:18,160 --> 00:17:20,640
So, she does her best to make sure
227
00:17:20,680 --> 00:17:23,680
that her rivals remain
in their cells.
228
00:17:24,800 --> 00:17:26,560
(WHINING SOUND)
229
00:17:26,599 --> 00:17:31,280
She does that by making a sound
beekeepers call a toot.
230
00:17:31,320 --> 00:17:33,480
(WHINY TOOT)
231
00:17:34,520 --> 00:17:35,680
(DEEPER HUM)
232
00:17:35,720 --> 00:17:37,640
Slowed down a thousand times
233
00:17:37,680 --> 00:17:41,480
and using new software that converts
vibration to colour,
234
00:17:41,520 --> 00:17:44,640
we can see
how she creates this call.
235
00:17:44,680 --> 00:17:46,880
(HUM)
236
00:17:50,960 --> 00:17:53,280
The vibrations travel down her legs,
237
00:17:53,320 --> 00:17:57,000
across the comb, and are detected
by the legs of the workers.
238
00:18:00,880 --> 00:18:04,160
(TOOTING)
239
00:18:04,200 --> 00:18:08,320
As she toots, the whole colony,
for a few seconds,
240
00:18:08,360 --> 00:18:12,920
stops moving...
(RUSTLING STOPS)
241
00:18:12,960 --> 00:18:16,760
..in recognition that a new queen
has ascended the throne.
242
00:18:18,720 --> 00:18:22,520
Each toot
is answered by a chorus of quacks
243
00:18:22,560 --> 00:18:25,600
from the rival queens
who are still within their cells
244
00:18:25,640 --> 00:18:27,560
and eager to emerge.
245
00:18:28,680 --> 00:18:31,920
But as long as the new queen
continues tooting,
246
00:18:31,960 --> 00:18:34,440
the workers will not release
her rivals.
247
00:18:37,120 --> 00:18:40,880
The crowned queen toots
repeatedly until, after a few days,
248
00:18:40,920 --> 00:18:44,760
she prepares to depart with half
of the workers in a swarm.
249
00:18:44,800 --> 00:18:46,840
(HUGE SQUEAKS AND RUSTLING)
250
00:18:47,800 --> 00:18:50,400
The sounds in the hive become
increasingly intense,
251
00:18:50,440 --> 00:18:54,040
until finally the swarm leaves
the nest.
252
00:18:55,640 --> 00:18:58,160
(UPLIFTING MUSIC)
253
00:19:05,680 --> 00:19:08,360
They re-assemble
on a nearby branch...
254
00:19:11,640 --> 00:19:14,920
..and a new colony
will soon be established.
255
00:19:22,600 --> 00:19:24,400
(CHORUS OF CROAKS AND HONKS)
256
00:19:28,760 --> 00:19:30,360
Many animals,
when they first appear,
257
00:19:30,400 --> 00:19:33,920
rely on their parents
for everything they need
258
00:19:33,960 --> 00:19:36,240
and use sound to keep in touch
with them.
259
00:19:36,280 --> 00:19:40,000
(CROAKING AND HONKING)
260
00:19:42,680 --> 00:19:48,160
20,00 flamingos breeding
off the Yucatan coast in Mexico.
261
00:19:51,080 --> 00:19:53,400
The noise here is deafening.
262
00:19:53,440 --> 00:19:55,800
(CHORUS OF GRUNTS AND HONKS)
263
00:19:57,040 --> 00:20:01,240
The chicks, nonetheless, are able
to exchange intimate sounds
264
00:20:01,280 --> 00:20:02,440
with their parents.
265
00:20:11,440 --> 00:20:14,200
(CROAKS)
266
00:20:14,240 --> 00:20:16,720
This one has only just hatched.
267
00:20:19,560 --> 00:20:23,040
The colony provides protection
for its members.
268
00:20:23,080 --> 00:20:29,000
But living in such a huge crowd
is nonetheless hazardous.
269
00:20:29,040 --> 00:20:32,480
the chick's very survival depends on
its ability
270
00:20:32,520 --> 00:20:35,840
to recognise the voices
of its parents.
271
00:20:38,240 --> 00:20:41,360
So it must learn to do so quickly,
272
00:20:41,400 --> 00:20:42,920
because within ten days of hatching,
273
00:20:42,960 --> 00:20:45,720
it and its parents will leave
the nest.
274
00:20:45,760 --> 00:20:46,920
(CROAKS, CHICK CHIRRUPS)
275
00:20:48,320 --> 00:20:51,520
The call of each flamingo is unique.
276
00:20:53,040 --> 00:20:55,440
It's a kind of vocal fingerprint.
277
00:20:55,480 --> 00:20:58,200
(CROAKS)
How the chick manages in such a din
278
00:20:58,240 --> 00:21:03,280
to memorise and pick out the calls
of its parents is unimaginable.
279
00:21:03,320 --> 00:21:05,280
But it does so.
280
00:21:05,320 --> 00:21:07,000
(CROAKS)
281
00:21:07,040 --> 00:21:09,960
(CHIRRUPING)
282
00:21:13,400 --> 00:21:14,720
(HONKING)
283
00:21:14,760 --> 00:21:16,920
(SOFT MUSIC)
284
00:21:23,160 --> 00:21:27,080
This one is taking its first steps
out of the nest.
285
00:21:29,680 --> 00:21:33,200
But it's not really ready
for the wider world.
286
00:21:38,520 --> 00:21:40,960
Eventually it becomes
a little braver.
287
00:21:42,320 --> 00:21:44,760
but now it has a new problem.
288
00:21:45,920 --> 00:21:49,960
It's growing fast and both it
and its parents need food.
289
00:21:51,840 --> 00:21:56,000
To get it, the adults must leave
the colony and their chick.
290
00:21:57,840 --> 00:22:00,560
The chick cannot fly and will be
unable to do so
291
00:22:00,600 --> 00:22:02,160
for another three months.
292
00:22:02,200 --> 00:22:05,720
So, until then,
it's very vulnerable.
293
00:22:07,840 --> 00:22:12,480
There are hundreds of youngsters
with the same problem.
294
00:22:12,520 --> 00:22:16,880
The young gather together
in an enormous creche.
295
00:22:18,240 --> 00:22:20,040
There's safety in numbers.
296
00:22:24,440 --> 00:22:28,080
A few adults have stayed behind
to keep the creche together.
297
00:22:31,600 --> 00:22:34,040
The others eventually return.
298
00:22:35,600 --> 00:22:39,120
But now each must recognise
its own chick
299
00:22:39,160 --> 00:22:41,880
among the densely packed flock
of thousands.
300
00:22:41,920 --> 00:22:44,600
(CACOPHONY OF CLUCKING
AND CHITTERING)
301
00:22:50,840 --> 00:22:53,800
Amazingly, each family trio —
male, female and chick —
302
00:22:55,640 --> 00:22:58,240
are able to recognise
one another's voices.
303
00:23:01,080 --> 00:23:02,080
(CROAKING)
304
00:23:03,760 --> 00:23:07,080
Distinguishing individual calls
among this deafening chorus
305
00:23:07,120 --> 00:23:08,280
must be difficult.
306
00:23:10,080 --> 00:23:12,720
And this male can't find his chick.
307
00:23:12,760 --> 00:23:13,920
(CROAKING)
308
00:23:15,480 --> 00:23:18,840
Adults aren't the only ones
who are searching.
309
00:23:22,520 --> 00:23:25,080
A crocodile is lurking nearby.
310
00:23:29,120 --> 00:23:30,840
(CALLS) The chick calls...
311
00:23:30,880 --> 00:23:32,240
(CROAKS)
312
00:23:32,280 --> 00:23:34,800
But it can't hear
its father's reply.
313
00:23:39,720 --> 00:23:42,160
The crocodile attacks.
314
00:23:45,080 --> 00:23:47,400
(ANXIOUS CHITTER)
315
00:23:59,560 --> 00:24:01,960
(HUGE CHORUS OF CALLS AND CROAKS)
316
00:24:08,800 --> 00:24:10,680
It's failed to grab a chick,
317
00:24:10,720 --> 00:24:14,880
but it did create dangerous
confusion in the flock.
318
00:24:17,240 --> 00:24:19,480
The chick has become separated
from the others
319
00:24:19,520 --> 00:24:21,680
and seems to be lost.
320
00:24:21,720 --> 00:24:23,520
(CHITTERS)
321
00:24:27,440 --> 00:24:30,560
It begs for food from any individual
that passes.
322
00:24:30,600 --> 00:24:32,400
(CHITTERS)
323
00:24:36,760 --> 00:24:40,200
Its father, in another part of
the flock, keeps calling.
324
00:24:40,240 --> 00:24:42,240
(CROAKS)
325
00:24:43,440 --> 00:24:46,360
But the chick is too far away
to hear him.
326
00:24:50,760 --> 00:24:54,240
And this is how many chicks
meet their end.
327
00:24:58,520 --> 00:25:00,280
But not this one.
328
00:25:07,400 --> 00:25:09,400
(HIGH-PITCHED CHIRRUP)
It keeps calling.
329
00:25:11,960 --> 00:25:14,440
And from across the lagoon...
(CROAKS)
330
00:25:14,480 --> 00:25:15,560
..its father replies.
331
00:25:17,520 --> 00:25:20,960
(CHITTERING AND CROAKING)
332
00:25:21,000 --> 00:25:23,720
The unique sound of the chick's
voice has been recognised
333
00:25:23,760 --> 00:25:28,200
by its father, and the two at last
are re-united.
334
00:25:36,480 --> 00:25:38,480
As young animals grow,
335
00:25:38,520 --> 00:25:42,600
they learn to recognise oncoming
dangers and become big enough
336
00:25:42,640 --> 00:25:45,360
for their voices to sound an alarm.
337
00:25:55,160 --> 00:25:57,000
(CHORUS OF HOWLS)
338
00:25:59,880 --> 00:26:01,600
A wolf pack, in Ontario, Canada.
339
00:26:05,400 --> 00:26:08,280
(EERIE HOWLING)
340
00:26:09,320 --> 00:26:12,760
This communal howl binds the pack
together
341
00:26:12,800 --> 00:26:15,480
and registers their ownership
of a territory.
342
00:26:15,520 --> 00:26:18,560
(WOLVES HOWLING)
343
00:26:22,080 --> 00:26:25,720
With only around 500
of these Eastern wolves left,
344
00:26:25,760 --> 00:26:29,240
this heart-stopping sound is now
extremely rare.
345
00:26:29,280 --> 00:26:30,880
(ALL HOWLING)
346
00:26:32,000 --> 00:26:35,400
But this chorus has some new voices.
347
00:26:35,440 --> 00:26:38,040
(HOWLING AND BARKING)
348
00:26:38,080 --> 00:26:41,360
It's August and the pups
are joining in.
349
00:26:43,440 --> 00:26:46,080
These youngsters, however,
create a problem...
350
00:26:46,920 --> 00:26:49,240
..one that could endanger them all.
351
00:26:50,080 --> 00:26:52,360
(BIRDSONG)
352
00:26:57,680 --> 00:26:59,600
(DRONE OF BUZZING)
353
00:27:00,520 --> 00:27:02,480
(CHIRPS)
354
00:27:02,520 --> 00:27:05,200
Now, in summer,
the days are over 14 hours long.
355
00:27:08,520 --> 00:27:11,400
So the wolves have to hunt
in the light.
356
00:27:14,400 --> 00:27:16,520
(WHINES)
357
00:27:18,080 --> 00:27:21,080
The pups are too big
to stay in the den,
358
00:27:21,120 --> 00:27:25,480
but too inexperienced to join in
the hunt.
359
00:27:25,520 --> 00:27:31,280
So the adults leave them
in an open area - a rendezvous site.
360
00:27:32,080 --> 00:27:36,760
Its very openness makes
it a great place for play.
361
00:27:36,800 --> 00:27:40,320
But this is a particularly dangerous
time in their lives.
362
00:27:41,240 --> 00:27:44,720
Half of them won't live beyond
their first year.
363
00:27:46,120 --> 00:27:50,400
What happens here and now will
determine whether these will do so.
364
00:27:58,040 --> 00:28:02,120
Two of the youngsters know exactly
where they are supposed to stay.
365
00:28:02,160 --> 00:28:05,640
But their sister can't resist
exploring.
366
00:28:21,280 --> 00:28:22,680
(HIGH-PITCHED TWEET)
367
00:28:25,720 --> 00:28:29,880
Distracted, she doesn't notice that
a black bear is approaching.
368
00:28:33,280 --> 00:28:37,720
This is one of the few animals
that will kill a wolf pup.
369
00:28:39,880 --> 00:28:43,240
The wandering youngster seems
unaware of the danger.
370
00:28:45,640 --> 00:28:47,360
But her brothers are.
371
00:28:50,640 --> 00:28:53,080
(DISTANT HOWLING)
372
00:28:53,120 --> 00:28:54,960
They sound the alarm.
(BOTH HOWL)
373
00:28:57,520 --> 00:29:01,440
Alerted, the wandering pup spots
the bear.
374
00:29:03,640 --> 00:29:04,720
(HOWLING)
375
00:29:10,320 --> 00:29:11,440
(BARKS)
376
00:29:16,560 --> 00:29:18,840
(BARKING AND HOWLING)
377
00:29:18,880 --> 00:29:22,640
Now the lives of all three pups
are at risk.
378
00:29:25,240 --> 00:29:28,760
But, as the bear moves in,
she hears a different call.
379
00:29:32,120 --> 00:29:33,560
It's her own cub.
380
00:29:33,600 --> 00:29:35,240
And he needs his mother.
381
00:29:35,280 --> 00:29:36,320
(GROANS)
382
00:29:38,680 --> 00:29:41,200
(GROANS)
383
00:29:41,240 --> 00:29:42,560
(HOWLS)
384
00:29:42,600 --> 00:29:44,960
It's been a lucky escape
for the pups...
385
00:29:45,000 --> 00:29:46,000
(HOWLING)
386
00:29:46,800 --> 00:29:49,160
..but they are not yet
in the clear.
387
00:29:51,360 --> 00:29:53,160
The pups' howls are shorter
and higher-pitched
388
00:29:53,200 --> 00:29:55,280
than those of the adults...
389
00:29:57,520 --> 00:30:00,600
..but they can still be heard
many miles away.
390
00:30:03,120 --> 00:30:06,840
(DEEPER HOWL)
And they are answered.
391
00:30:08,280 --> 00:30:10,040
(HOWLS)
392
00:30:14,240 --> 00:30:17,080
The sound has alerted an adult wolf.
393
00:30:20,520 --> 00:30:22,800
(PURPOSEFUL MUSIC)
394
00:30:24,920 --> 00:30:27,040
(HOWLS)
395
00:30:28,760 --> 00:30:29,800
It's their father.
396
00:30:31,040 --> 00:30:32,360
(PUPS WHIMPER)
397
00:30:32,400 --> 00:30:34,400
He's returned with food
for the pups.
398
00:30:35,440 --> 00:30:37,120
(EXCITED YELPS)
399
00:30:40,200 --> 00:30:45,520
As dusk falls, the pack celebrates
with a reunion chorus.
400
00:30:45,560 --> 00:30:48,240
(DISTANT CHORUS OF HOWLS)
401
00:30:49,400 --> 00:30:52,960
Their voices have been crucial
in keeping the pack together.
402
00:30:53,000 --> 00:30:55,560
(DISTANT EERIE HOWLS)
403
00:30:55,600 --> 00:30:58,240
But many animals issue
warning calls
404
00:30:58,280 --> 00:31:01,160
that contain
far more complex information.
405
00:31:01,200 --> 00:31:02,960
(WHIMPERING)
406
00:31:05,760 --> 00:31:09,520
The meerkats, as they grow,
learn how to find their own meals.
407
00:31:12,160 --> 00:31:15,120
And they are discovering how
to avoid becoming someone else's.
408
00:31:17,400 --> 00:31:20,400
The desert is full of
hungry mouths...
409
00:31:21,840 --> 00:31:25,600
..and meerkats are small
and obviously edible.
410
00:31:28,680 --> 00:31:31,480
Their defence is neither armour
nor weapon.
411
00:31:33,840 --> 00:31:36,360
Instead, they use sound -
412
00:31:36,400 --> 00:31:38,200
a complicated system of alarms.
413
00:31:41,600 --> 00:31:44,680
These calls are not just
generalised alerts.
414
00:31:44,720 --> 00:31:47,360
(SHORT WHOOPS)
415
00:31:50,120 --> 00:31:52,320
This one warns of
a flying predator...
416
00:31:53,800 --> 00:31:55,280
(SHORT WHOOPS CONTINUE)
417
00:31:55,320 --> 00:31:58,040
..and those hearing it look up
and scan the sky.
418
00:31:58,080 --> 00:31:59,080
(WHOOPING)
419
00:32:06,760 --> 00:32:10,480
Danger on the ground is indicated
by a different call.
420
00:32:10,520 --> 00:32:12,920
(HIGHER-PITCHED HOOTS)
421
00:32:14,000 --> 00:32:15,360
Best to look around.
422
00:32:17,640 --> 00:32:19,400
(GRUNTING)
423
00:32:21,640 --> 00:32:25,960
Snakes are identified by
a third signal.
424
00:32:28,320 --> 00:32:31,880
(GRUNTS)
425
00:32:31,920 --> 00:32:34,240
A call from the look-out
summons others
426
00:32:34,280 --> 00:32:36,320
to come and help drive it away.
427
00:32:36,360 --> 00:32:38,360
(COBRA HISSES, MEERKATS GROWL)
428
00:32:45,120 --> 00:32:47,560
Meerkat warnings are so detailed
429
00:32:47,600 --> 00:32:50,040
that they can be a bit confusing
for youngsters.
430
00:32:54,080 --> 00:32:57,320
So the best thing is to do
what everybody else is doing.
431
00:32:58,200 --> 00:32:59,640
(SQUEAKS)
432
00:33:01,920 --> 00:33:04,360
The calls also carry
other information,
433
00:33:04,400 --> 00:33:07,680
such as how fast a predator
is approaching.
434
00:33:09,160 --> 00:33:12,480
And there is one call
which should never be ignored.
435
00:33:12,520 --> 00:33:14,040
(SHORT GRUNTS)
436
00:33:14,080 --> 00:33:19,520
This is the high-urgency call,
a warning of immediate danger.
437
00:33:19,560 --> 00:33:23,400
(SERIES OF SHORT GRUNTS)
438
00:33:23,440 --> 00:33:26,120
Not to react to this
could be disastrous.
439
00:33:29,640 --> 00:33:33,600
So when you hear this call...
(GRUNTING)
440
00:33:33,640 --> 00:33:35,160
..run for your life!
441
00:33:42,880 --> 00:33:44,920
(GRUNTS)
442
00:33:44,960 --> 00:33:46,960
(BIRDSONG AND CACKLING)
443
00:33:49,520 --> 00:33:53,120
Sounds in the open air are important
for many animals.
444
00:33:54,880 --> 00:33:58,720
But there is another world of sound
with which we are far less familiar.
445
00:33:59,880 --> 00:34:03,040
We can't hear very well underwater,
446
00:34:03,080 --> 00:34:06,720
because our ears are shaped
to work in the air.
447
00:34:07,480 --> 00:34:11,480
But there is a way in which we can
eavesdrop on this underwater world,
448
00:34:11,520 --> 00:34:14,880
by using a special kind of
underwater microphone
449
00:34:14,920 --> 00:34:17,440
called a hydrophone.
450
00:34:21,400 --> 00:34:24,760
(PULSING CHIRP-LIKE SOUNDS)
451
00:34:24,800 --> 00:34:28,159
I don't know exactly what's making
those noises,
452
00:34:28,199 --> 00:34:32,480
it's probably some small
invertebrates or maybe a small fish.
453
00:34:32,520 --> 00:34:36,440
We've known for some time that
quite a lot of fish produce sounds.
454
00:34:37,440 --> 00:34:40,480
It's only recently, however,
that scientists have discovered
455
00:34:40,520 --> 00:34:43,639
just how widespread that ability is.
456
00:34:54,440 --> 00:34:59,880
The ocean covers around 70% of
our planet's surface.
457
00:35:06,160 --> 00:35:08,280
And sound also plays a crucial role
458
00:35:08,320 --> 00:35:12,280
in the lives of many of the animals
that live in it.
459
00:35:12,320 --> 00:35:14,280
(CROAKING AND CREAKING SOUNDS)
460
00:35:17,800 --> 00:35:20,200
Coral reefs are surprisingly
noisy places.
461
00:35:21,320 --> 00:35:22,400
(DEEP CROAKS)
462
00:35:23,960 --> 00:35:25,960
Many of these sounds are made
by fish.
463
00:35:27,480 --> 00:35:30,840
(GRUNTING AND CROAKING)
464
00:35:40,400 --> 00:35:42,920
Here too, sound can be important
465
00:35:42,960 --> 00:35:45,680
from the very beginning of
an animal's life.
466
00:35:47,320 --> 00:35:51,840
Without it, one of the most
strikingly coloured fish on the reef
467
00:35:51,880 --> 00:35:54,200
would never find its way home.
468
00:35:58,440 --> 00:36:00,840
It's just days before a full moon
469
00:36:00,880 --> 00:36:04,560
and this female clownfish is about
to lay her eggs.
470
00:36:10,200 --> 00:36:12,280
Clownfish live in small communities,
471
00:36:13,520 --> 00:36:18,280
each based around a particularly
large anemone.
472
00:36:23,760 --> 00:36:28,480
In this busy colony,
only two adults will reproduce -
473
00:36:28,520 --> 00:36:31,200
the largest, the dominant female...
474
00:36:32,120 --> 00:36:35,680
..and her partner, the next in size,
the dominant male.
475
00:36:37,560 --> 00:36:40,800
There's a strict hierarchy,
one that's based on size,
476
00:36:40,840 --> 00:36:43,280
but policed by sound.
477
00:36:44,920 --> 00:36:46,120
(CROAKY GRUNTS)
478
00:36:46,160 --> 00:36:50,280
Her larger body enables her
to make the deepest sound
479
00:36:50,320 --> 00:36:54,560
by snapping her teeth together
to produce pops and pulses.
480
00:36:54,600 --> 00:36:57,440
(PULSING GRUNTS)
481
00:37:02,320 --> 00:37:04,960
(SHORT GRUNTS)
482
00:37:07,160 --> 00:37:10,000
The male signals
his subordinate status
483
00:37:10,040 --> 00:37:12,120
by quivering his head
484
00:37:12,160 --> 00:37:14,360
and producing a purring noise.
485
00:37:16,800 --> 00:37:20,840
And everyone around the anemone
knows that she is the boss.
486
00:37:25,840 --> 00:37:28,960
At full moon, she will be ready
to lay eggs.
487
00:37:31,440 --> 00:37:34,480
So the group needs to find
a firm surface for them.
488
00:37:36,680 --> 00:37:39,000
A coconut shell, brought in
by the currents,
489
00:37:39,040 --> 00:37:41,080
would be ideal.
490
00:37:43,480 --> 00:37:45,760
But it needs to be moved
into the right position.
491
00:37:47,800 --> 00:37:50,560
She indicates her needs
with a low-pitched grunt,
492
00:37:50,600 --> 00:37:55,320
and the juveniles in the colony
comply by shaking their heads.
493
00:38:03,000 --> 00:38:04,960
(MYSTERIOUS MUSIC)
494
00:38:05,000 --> 00:38:09,320
Working together, they manoeuvre
the coconut shell into position.
495
00:38:12,040 --> 00:38:15,360
Team work takes a lot of
co-ordination,
496
00:38:15,400 --> 00:38:18,200
and a lot of grunting
and jaw-grinding.
497
00:38:25,960 --> 00:38:30,120
Next, the stage needs
to be prepared.
498
00:38:36,360 --> 00:38:38,080
And at last, the moment arrives.
499
00:38:44,680 --> 00:38:48,040
She lays her eggs in neat lines.
500
00:39:02,920 --> 00:39:07,400
The male then makes HIS contribution
- fertilising the eggs.
501
00:39:14,440 --> 00:39:16,000
Now he takes charge.
502
00:39:20,240 --> 00:39:24,080
For the next seven days, he will fan
and clean the eggs as they develop.
503
00:39:34,160 --> 00:39:37,480
Three more days and the embryos
begin to respond
504
00:39:37,520 --> 00:39:39,800
to the sounds around them.
505
00:39:39,840 --> 00:39:41,760
(GRUNTING)
506
00:39:41,800 --> 00:39:45,960
The sounds that they hear now
could play a critical role
507
00:39:46,000 --> 00:39:48,400
in the next stage of their lives.
508
00:39:53,680 --> 00:39:58,200
But a different sort of noise is
already threatening their survival.
509
00:40:04,480 --> 00:40:07,840
The male reacts to the noise of
a boat as he would to a predator.
510
00:40:12,880 --> 00:40:14,800
If there is constant motor traffic,
511
00:40:14,840 --> 00:40:18,840
he spends more time hiding
and less tending the eggs...
512
00:40:18,880 --> 00:40:21,320
so they are more vulnerable
to predators and disease.
513
00:40:21,360 --> 00:40:24,720
(THRUM OF MOTOR BOAT)
514
00:40:25,920 --> 00:40:29,280
The noise around these reefs
has increased dramatically
515
00:40:29,320 --> 00:40:33,840
in recent decades, and that has
affected the lives of the fish here.
516
00:40:36,560 --> 00:40:40,240
But the clownfish father has managed
to keep his young healthy,
517
00:40:40,280 --> 00:40:43,160
and a week later,
they begin to change.
518
00:40:46,280 --> 00:40:49,240
The plankton-sized fry wriggle free
519
00:40:49,280 --> 00:40:53,040
and are then swept away from
the reef by ocean currents.
520
00:40:53,080 --> 00:40:55,480
(UPLIFTING CELLO MUSIC)
521
00:41:03,760 --> 00:41:08,680
For ten days, the larval fish drift
out in the open ocean.
522
00:41:14,640 --> 00:41:16,240
(BIRDS CRY)
523
00:41:20,200 --> 00:41:24,120
By the time that each is about
the size of a grain of rice,
524
00:41:24,160 --> 00:41:27,760
they are strong enough to swim
against the current.
525
00:41:28,960 --> 00:41:32,240
And they need to find their way
back to a reef.
526
00:41:40,200 --> 00:41:43,560
The key to their homecoming
is sound.
527
00:41:45,720 --> 00:41:50,640
Underwater, the sounds of a reef
can be heard for many miles around.
528
00:41:50,680 --> 00:41:55,280
The tiny young clownfish can hear
this noise and swim towards it.
529
00:41:58,720 --> 00:42:02,080
They can even judge the health of
a reef by its sound.
530
00:42:02,120 --> 00:42:05,480
The noisier it is,
the more vigorous it is.
531
00:42:05,520 --> 00:42:07,520
(CLACKING AND BUBBLING)
532
00:42:26,160 --> 00:42:29,880
The anemone will provide him with
shelter and sanctuary
533
00:42:29,920 --> 00:42:33,640
for the rest of his life.
534
00:42:33,680 --> 00:42:36,320
Sound has brought him home.
535
00:42:36,360 --> 00:42:38,280
(UPLIFTING MUSIC)
536
00:42:40,920 --> 00:42:44,440
For these fish, and for many other
baby animals,
537
00:42:44,480 --> 00:42:48,920
sound is crucial for launching
themselves into the world
538
00:42:48,960 --> 00:42:53,480
and learning what they need to stay
safe and to thrive.
539
00:42:54,560 --> 00:42:58,040
For them, sound is survival.
540
00:43:04,960 --> 00:43:07,440
(GENTLE MUSIC)
541
00:43:22,640 --> 00:43:24,720
What's one of the close ones
over here...
542
00:43:24,760 --> 00:43:28,520
Biologist Mark Meekan
became fascinated by coral reefs
543
00:43:28,560 --> 00:43:29,840
more than 30 years ago.
544
00:43:31,040 --> 00:43:33,520
'Coral reefs are these incredible
habitats
545
00:43:33,560 --> 00:43:37,360
and I've always been struck by
their diversity
546
00:43:37,400 --> 00:43:39,720
and just incredible beauty.'
547
00:43:39,760 --> 00:43:43,480
Today he is fighting to save
these reefs
548
00:43:43,520 --> 00:43:46,120
from the ravages of climate change.
549
00:43:46,160 --> 00:43:49,800
This is Australia's Ningaloo Reef
550
00:43:49,840 --> 00:43:52,520
that stretches along the country's
western coast.
551
00:43:54,480 --> 00:43:55,760
But over decades of research,
552
00:43:55,800 --> 00:43:58,440
Mark discovered something else —
553
00:43:58,480 --> 00:44:01,720
that coral reefs are full of sound.
554
00:44:04,160 --> 00:44:06,480
A hunch about the significance
of this inspired him
555
00:44:06,520 --> 00:44:11,400
to try and find a way to use
this sound to save coral reefs.
556
00:44:13,000 --> 00:44:14,840
'If we could hear underwater,
557
00:44:14,880 --> 00:44:18,640
we would hear this cacophony of
hoots and yowls,
558
00:44:18,680 --> 00:44:21,440
really strange screams made by fish.
559
00:44:22,600 --> 00:44:26,120
And these little fish may actually
be helping the coral to grow.
560
00:44:26,160 --> 00:44:31,720
Basically, by sheltering in
the coral, pooping in the coral,
561
00:44:31,760 --> 00:44:33,120
fertilising the coral.
562
00:44:35,040 --> 00:44:38,760
A healthy reef is really
very noisy.'
563
00:44:38,800 --> 00:44:41,080
This sound is key.
564
00:44:41,120 --> 00:44:44,960
After hatching, reef fish are swept
out to sea.
565
00:44:45,000 --> 00:44:48,960
When they return,
they use these healthy sounds
566
00:44:49,000 --> 00:44:51,680
to choose the reef
that will be their home.
567
00:44:51,720 --> 00:44:54,040
And this was just a wow moment.
568
00:44:54,080 --> 00:44:57,920
We suddenly thought, "We can
actually use this to help the reef."
569
00:45:00,480 --> 00:45:05,280
The result is a multi-million-dollar
project with one goal —
570
00:45:05,320 --> 00:45:10,320
to discover if sound can also help
save a dying reef.
571
00:45:16,000 --> 00:45:20,520
The first step is to collect three
and a half tons of coral debris.
572
00:45:22,440 --> 00:45:24,840
It's alive and extremely vulnerable.
573
00:45:28,920 --> 00:45:31,320
Mark's team build
60 experimental reefs.
574
00:45:34,280 --> 00:45:38,440
Underwater speakers are guided
to some of these and turned on.
575
00:45:41,120 --> 00:45:43,400
It's their job to attract fish
576
00:45:43,440 --> 00:45:46,160
by playing the sounds of
a healthy reef.
577
00:45:47,320 --> 00:45:51,280
The results will be compared
to experimental reefs
578
00:45:51,320 --> 00:45:53,240
without speakers.
579
00:45:57,880 --> 00:46:00,960
At Ningaloo, it's a new moon.
580
00:46:03,760 --> 00:46:06,440
Tonight,
the reef fish are coming home.
581
00:46:08,320 --> 00:46:09,880
(BUBBLING AND POPPING SOUNDS)
582
00:46:09,920 --> 00:46:13,400
At the experimental sites,
speakers are on,
583
00:46:13,440 --> 00:46:17,120
broadcasting the sounds of
a healthy reef.
584
00:46:19,280 --> 00:46:20,960
OK, get ready, Daphne.
585
00:46:21,000 --> 00:46:23,440
They are laying out light traps
586
00:46:23,480 --> 00:46:26,680
and assessing if the speakers are
attracting fish
587
00:46:26,720 --> 00:46:30,280
to the experimental reefs with sound
588
00:46:30,320 --> 00:46:32,400
versus ones without.
589
00:46:33,360 --> 00:46:34,680
And they are!
590
00:46:34,720 --> 00:46:36,800
'We actually got the fish to come.
591
00:46:38,280 --> 00:46:41,480
They arrived in big numbers
on the reefs.'
592
00:46:45,440 --> 00:46:50,360
Mark's team have been photographing
these reefs for 12 months.
593
00:46:54,800 --> 00:46:57,760
Now they're going to see if the fish
have helped the coral to grow again.
594
00:47:01,240 --> 00:47:05,560
So, on the left here, we've got our
patch reef model from one year ago.
595
00:47:05,600 --> 00:47:09,360
And on the right-hand side, our reef
model from a couple of days ago.
596
00:47:09,400 --> 00:47:13,400
You can see fairly obviously
already
597
00:47:13,440 --> 00:47:16,200
there's been a fair bit of growth
over the year.
598
00:47:18,520 --> 00:47:22,240
Wow!
This one's roughly 20cm across,
599
00:47:22,280 --> 00:47:23,640
maximum diameter,
600
00:47:23,680 --> 00:47:26,000
and the same colony a year later,
it's almost 40.
601
00:47:26,040 --> 00:47:30,040
So we've doubled in size.
Fantastic, man.
602
00:47:31,440 --> 00:47:32,680
(LAUGHS)
603
00:47:32,720 --> 00:47:34,400
Wow.
604
00:47:34,440 --> 00:47:35,800
(SOUNDS OF PIPS AND POPS)
605
00:47:37,800 --> 00:47:40,000
oral reefs today are in such a state
606
00:47:40,040 --> 00:47:43,640
that we're beyond shouting
to everybody that it's bad.
607
00:47:43,680 --> 00:47:47,240
We have to move into doing something
about it.
608
00:47:50,520 --> 00:47:54,560
The sound made by fish might just be
a vital tool
609
00:47:54,600 --> 00:47:58,640
to help scientists save coral reefs
around the globe.
610
00:48:03,600 --> 00:48:06,640
(SPRINGTIME BIRDSONG)
611
00:48:09,120 --> 00:48:11,400
(CUCKOO CALLS)
612
00:48:13,720 --> 00:48:16,240
(BLACKBIRD SINGS)
613
00:48:17,920 --> 00:48:20,680
(SHEEP BLEATS)
614
00:48:25,800 --> 00:48:27,560
(WOOD PIGEON COOING)
615
00:48:33,600 --> 00:48:36,040
AccessibleCustomerService@sky.uk
46568
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.