Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:43,802 --> 00:00:48,562
Much of our planet
still remains unexplored...
2
00:00:51,322 --> 00:00:54,482
..for most of it is covered
by water.
3
00:00:57,202 --> 00:01:01,602
Every journey below the surface
can reveal something extraordinary.
4
00:01:01,642 --> 00:01:02,002
Every journey below the surface
can reveal something extraordinary.
5
00:01:05,442 --> 00:01:10,122
More than a thousand new species
are discovered here every year.
6
00:01:10,162 --> 00:01:11,082
More than a thousand new species
are discovered here every year.
7
00:01:25,322 --> 00:01:30,282
The ocean is home to 80%
of all animal life on Planet Earth.
8
00:01:30,322 --> 00:01:33,322
The ocean is home to 80%
of all animal life on Planet Earth.
9
00:01:41,082 --> 00:01:46,242
But today,
thriving in this varied world
10
00:01:46,282 --> 00:01:50,482
sometimes demands
the most surprising behaviour.
11
00:01:50,522 --> 00:01:51,082
sometimes demands
the most surprising behaviour.
12
00:02:12,082 --> 00:02:15,482
{\an8}The shallow seas of the tropics.
13
00:02:18,322 --> 00:02:21,642
This may look like a paradise...
14
00:02:24,722 --> 00:02:29,162
..but beneath the surface,
it is an arena
15
00:02:29,202 --> 00:02:32,562
for constant
life-and-death struggles,
16
00:02:32,602 --> 00:02:36,042
where not everything
is quite as it seems.
17
00:02:45,642 --> 00:02:49,242
A predatory lionfish...
18
00:02:52,082 --> 00:02:55,322
..on the hunt for shrimp
and small fish.
19
00:03:04,242 --> 00:03:08,442
With so many places
for its prey to hide,
20
00:03:08,482 --> 00:03:11,442
the lionfish has to be patient.
21
00:03:18,282 --> 00:03:21,642
This shrimp appears tempting.
22
00:03:23,242 --> 00:03:25,722
As the lion-fish closes in,
23
00:03:25,762 --> 00:03:30,362
it fans out its fins
to disorientate its prey.
24
00:03:30,402 --> 00:03:30,522
it fans out its fins
to disorientate its prey.
25
00:03:43,202 --> 00:03:46,122
The hunter becomes the hunted.
26
00:03:52,642 --> 00:03:55,082
Tricked by one
of the shallow sea's
27
00:03:55,122 --> 00:03:57,642
most extraordinary predators...
28
00:04:01,722 --> 00:04:04,442
..a clown frogfish!
29
00:04:07,002 --> 00:04:10,522
On its head, it carries
a fishing rod -
30
00:04:10,562 --> 00:04:12,882
a modified dorsal fin,
31
00:04:12,922 --> 00:04:17,802
baited with a lure -
easily mistaken for a shrimp.
32
00:04:28,242 --> 00:04:30,922
But, when the fish stop biting,
33
00:04:30,962 --> 00:04:33,522
it's time to pack the rod away
34
00:04:33,562 --> 00:04:35,802
and move on.
35
00:04:38,882 --> 00:04:43,682
And, for a frogfish,
that takes time.
36
00:04:43,722 --> 00:04:44,482
And, for a frogfish,
that takes time.
37
00:04:55,202 --> 00:04:59,602
Rather than swim, frogfish walk!
38
00:05:01,602 --> 00:05:05,322
Its fins have, in effect,
become feet.
39
00:05:14,882 --> 00:05:16,962
It may not look pretty,
40
00:05:17,002 --> 00:05:21,922
but what appears to be coral living
on its skin is actually camouflage.
41
00:05:21,962 --> 00:05:23,522
but what appears to be coral living
on its skin is actually camouflage.
42
00:05:37,242 --> 00:05:39,842
As every good angler knows,
43
00:05:39,882 --> 00:05:42,962
picking the right spot is important.
44
00:05:48,442 --> 00:05:51,882
Jigging the rod sends out
pressure waves
45
00:05:51,922 --> 00:05:55,002
to attract the attention
of possible prey.
46
00:06:03,322 --> 00:06:06,362
These dragonets
are certainly interested.
47
00:06:19,042 --> 00:06:21,402
Almost there.
48
00:06:35,522 --> 00:06:38,162
Hook, line, and sinker.
49
00:06:50,322 --> 00:06:53,402
Like all shallow seas,
the cold waters
50
00:06:53,442 --> 00:06:56,442
off the coast of North America,
51
00:06:56,482 --> 00:07:00,082
benefit from the intensity
of the sunshine.
52
00:07:07,282 --> 00:07:09,242
Here, that fuels
53
00:07:09,282 --> 00:07:12,722
one of the fastest-growing
organisms on the planet...
54
00:07:14,762 --> 00:07:16,682
..giant kelp.
55
00:07:19,482 --> 00:07:23,162
Towering forests
can eventually reach the height
56
00:07:23,202 --> 00:07:25,602
of a 12-storey building.
57
00:07:38,642 --> 00:07:43,242
These forests are nurseries
for young horn sharks.
58
00:07:43,282 --> 00:07:43,602
These forests are nurseries
for young horn sharks.
59
00:07:47,122 --> 00:07:49,282
As the sun begins to set,
60
00:07:49,322 --> 00:07:52,442
they leave their daytime shelter
61
00:07:52,482 --> 00:07:57,042
and set off into the heart
of the kelp forest to find food.
62
00:07:57,082 --> 00:07:58,002
and set off into the heart
of the kelp forest to find food.
63
00:08:08,282 --> 00:08:10,242
Barely half a metre long,
64
00:08:10,282 --> 00:08:13,962
this little shark
is extremely vulnerable.
65
00:08:20,802 --> 00:08:23,802
There are monsters here.
66
00:08:23,842 --> 00:08:26,642
A giant sea bass -
67
00:08:26,682 --> 00:08:29,562
weighing over 200kg...
68
00:08:32,842 --> 00:08:36,442
..and wolf-eels, with big teeth
69
00:08:36,482 --> 00:08:39,722
that can crush
little red sea urchins.
70
00:08:42,122 --> 00:08:45,762
But the biggest danger
comes from other sharks -
71
00:08:50,002 --> 00:08:53,082
houndsharks...
72
00:08:56,762 --> 00:09:00,402
..and huge broadnose sevengills.
73
00:09:12,162 --> 00:09:16,682
In this forest,
it pays to keep a low profile.
74
00:09:50,162 --> 00:09:52,562
An angel shark...
75
00:09:56,002 --> 00:10:00,002
..one of the most deadly sharks
in the kelp forest,
76
00:10:00,042 --> 00:10:03,562
and certainly
the best camouflaged.
77
00:10:14,202 --> 00:10:19,042
An angel shark
will lie in wait for days...
78
00:10:28,562 --> 00:10:33,202
..but this one has already attracted
too much attention.
79
00:10:33,242 --> 00:10:34,322
..but this one has already attracted
too much attention.
80
00:10:40,962 --> 00:10:43,602
It's not welcome here.
81
00:10:50,402 --> 00:10:52,922
Now, the coast is clear.
82
00:11:00,962 --> 00:11:04,602
But angel sharks hunt
around the clock.
83
00:11:14,842 --> 00:11:18,602
Openings for breathing,
called spiracles,
84
00:11:18,642 --> 00:11:21,962
blow out sand
that helps cover its body.
85
00:11:29,242 --> 00:11:32,002
The trap is set.
86
00:11:43,522 --> 00:11:48,642
Staying close to the seabed is
a good way to avoid most predators.
87
00:11:48,682 --> 00:11:49,562
Staying close to the seabed is
a good way to avoid most predators.
88
00:12:39,082 --> 00:12:42,482
Faster than the blink of an eye.
89
00:12:45,882 --> 00:12:48,322
But it's not over yet.
90
00:13:00,402 --> 00:13:04,442
Horn sharks have a secret weapon.
91
00:13:09,242 --> 00:13:13,402
Sharp spikes keep them very much
off the menu for most.
92
00:13:20,042 --> 00:13:24,282
So, this young horn shark
can hunt in safety...
93
00:13:24,322 --> 00:13:25,722
So, this young horn shark
can hunt in safety...
94
00:13:27,722 --> 00:13:29,722
..for now.
95
00:13:56,362 --> 00:14:01,282
Violent winter storms
batter these kelp forests.
96
00:14:08,642 --> 00:14:11,682
The plants can be ripped
from the seafloor...
97
00:14:14,682 --> 00:14:18,242
..and carried away far out to sea.
98
00:14:30,322 --> 00:14:35,482
The open ocean
is a vast, featureless desert.
99
00:14:39,482 --> 00:14:43,962
Even a small piece of drifting kelp
can become valuable.
100
00:14:44,002 --> 00:14:44,082
Even a small piece of drifting kelp
can become valuable.
101
00:14:54,122 --> 00:14:58,842
It's just what these fish
have been searching for.
102
00:14:58,882 --> 00:14:59,042
It's just what these fish
have been searching for.
103
00:15:00,882 --> 00:15:05,242
Here, shelter where eggs can be laid
unobtrusively is rare...
104
00:15:05,282 --> 00:15:05,922
Here, shelter where eggs can be laid
unobtrusively is rare...
105
00:15:07,762 --> 00:15:10,482
..so they make the most of it.
106
00:15:12,522 --> 00:15:16,682
Each female produces
up to a thousand eggs,
107
00:15:16,722 --> 00:15:20,002
and the males rush in
to fertilise them.
108
00:15:30,642 --> 00:15:34,962
All this activity attracts
the attention of blue sharks.
109
00:15:35,002 --> 00:15:35,882
All this activity attracts
the attention of blue sharks.
110
00:15:38,882 --> 00:15:41,482
They can travel thousands of miles
111
00:15:41,522 --> 00:15:44,122
through the ocean
in search of food...
112
00:15:48,602 --> 00:15:53,042
..and they may not have eaten
for weeks.
113
00:15:53,082 --> 00:15:53,442
..and they may not have eaten
for weeks.
114
00:15:53,482 --> 00:15:56,202
It seems that they're in luck.
115
00:16:04,242 --> 00:16:08,122
But these fish are no easy meal.
116
00:16:14,162 --> 00:16:16,602
They are flying fish!
117
00:17:15,682 --> 00:17:18,442
The blue shark, however,
118
00:17:18,482 --> 00:17:20,562
are not here for the fish...
119
00:17:23,602 --> 00:17:27,722
..they have come for the caviar.
120
00:17:42,402 --> 00:17:45,282
But flying fish lay so many eggs,
121
00:17:45,322 --> 00:17:48,682
that the sharks' feasts
hardly make an impact.
122
00:17:57,082 --> 00:18:01,602
And, in a few months' time, a new
generation will take to the skies.
123
00:18:01,642 --> 00:18:02,482
And, in a few months' time, a new
generation will take to the skies.
124
00:18:15,722 --> 00:18:20,602
Floating islands of weed
are always attractive to creatures
125
00:18:20,642 --> 00:18:24,082
looking for shelter
out in the big blue.
126
00:18:25,722 --> 00:18:30,162
But, in today's ocean, they are
being replaced by something else...
127
00:18:35,602 --> 00:18:37,322
..plastic.
128
00:18:39,402 --> 00:18:43,962
12 million tons of it
end up in the ocean every year.
129
00:18:47,482 --> 00:18:52,602
The deadliest kind are discarded
fishing lines and nets.
130
00:18:52,642 --> 00:18:52,922
The deadliest kind are discarded
fishing lines and nets.
131
00:18:56,642 --> 00:19:01,082
Each year, it's likely over
half a million animals are ensnared
132
00:19:01,122 --> 00:19:01,362
Each year, it's likely over
half a million animals are ensnared
133
00:19:01,402 --> 00:19:05,002
and killed by these "ghost nets."
134
00:19:14,642 --> 00:19:16,962
But some animals are learning
135
00:19:17,002 --> 00:19:20,042
how to take advantage
of the plastic rafts...
136
00:19:22,922 --> 00:19:27,482
..and use them for shelter,
or even as a home.
137
00:19:30,482 --> 00:19:35,082
This male Columbus crab - barely
bigger than your thumb nail -
138
00:19:35,122 --> 00:19:35,482
This male Columbus crab - barely
bigger than your thumb nail -
139
00:19:35,522 --> 00:19:37,882
is a castaway.
140
00:19:41,082 --> 00:19:42,602
Clinging to his net,
141
00:19:42,642 --> 00:19:46,602
he may have been drifting
on ocean currents for months.
142
00:19:49,682 --> 00:19:53,562
Now, fully grown,
he needs to find a partner.
143
00:19:56,002 --> 00:19:58,122
But where?
144
00:20:05,762 --> 00:20:08,162
Certainly not here,
145
00:20:08,202 --> 00:20:10,962
alone on the net.
146
00:20:19,762 --> 00:20:25,042
Columbus crabs are not good
swimmers, so this male is marooned.
147
00:20:34,962 --> 00:20:38,482
Perhaps a passing loggerhead turtle
could be the chance
148
00:20:38,522 --> 00:20:40,202
to hitch a lift.
149
00:21:31,322 --> 00:21:32,682
Made it!
150
00:21:35,682 --> 00:21:39,882
But there's more than one
passenger here -
151
00:21:39,922 --> 00:21:42,882
a female Columbus crab!
152
00:21:50,722 --> 00:21:54,322
They waste no time
in getting acquainted...
153
00:21:57,762 --> 00:22:00,122
..and start to mate.
154
00:22:07,882 --> 00:22:12,322
This pair may well stay together
for the rest of their lives.
155
00:22:12,362 --> 00:22:12,562
This pair may well stay together
for the rest of their lives.
156
00:22:22,482 --> 00:22:27,122
A turtle, after all,
makes an excellent home.
157
00:22:35,482 --> 00:22:39,962
In return, the crabs provide
an onboard grooming service.
158
00:22:40,002 --> 00:22:40,482
In return, the crabs provide
an onboard grooming service.
159
00:23:11,442 --> 00:23:16,122
Finding a partner in the vast ocean
is not easy.
160
00:23:16,162 --> 00:23:16,762
Finding a partner in the vast ocean
is not easy.
161
00:23:23,402 --> 00:23:27,242
Dawn in the Sea of Cortez...
162
00:23:50,722 --> 00:23:53,162
..Mobula rays.
163
00:24:13,402 --> 00:24:17,162
They're gathering here,
most likely to breed.
164
00:24:22,162 --> 00:24:25,122
No-one is sure why they leap,
165
00:24:25,162 --> 00:24:29,402
but the loud splashes
certainly seem to attract more rays.
166
00:24:29,442 --> 00:24:29,682
but the loud splashes
certainly seem to attract more rays.
167
00:24:33,922 --> 00:24:38,122
Other creatures, however,
are also listening.
168
00:24:48,602 --> 00:24:51,882
Orca have heard the splashes.
169
00:25:13,482 --> 00:25:17,722
This female specialises
in hunting rays.
170
00:25:25,002 --> 00:25:28,802
But today, she is teaching
two youngsters
171
00:25:28,842 --> 00:25:33,082
the finer points
of Mobula ray hunting.
172
00:25:44,842 --> 00:25:49,082
The rays are fast
and can outmanoeuvre an orca.
173
00:25:49,122 --> 00:25:49,202
The rays are fast
and can outmanoeuvre an orca.
174
00:25:57,482 --> 00:26:01,842
She knows she needs to herd
the prey into a tight group...
175
00:26:01,882 --> 00:26:02,242
She knows she needs to herd
the prey into a tight group...
176
00:26:07,242 --> 00:26:10,722
..but she can't do that on her own.
177
00:26:10,762 --> 00:26:14,682
It will take teamwork,
178
00:26:14,722 --> 00:26:17,402
and that is today's lesson.
179
00:26:24,802 --> 00:26:28,762
The young orca
are quick to catch on.
180
00:26:33,322 --> 00:26:36,602
The rays are surrounded.
181
00:26:40,402 --> 00:26:42,682
They dive...
182
00:26:45,602 --> 00:26:50,722
..only to be forced back up again
by the experienced female.
183
00:26:54,482 --> 00:26:59,242
And now, with the exhausted rays
trapped against the surface,
184
00:26:59,282 --> 00:26:59,842
And now, with the exhausted rays
trapped against the surface,
185
00:26:59,882 --> 00:27:02,122
she attacks...
186
00:27:15,242 --> 00:27:19,082
..and the young ones
follow her lead.
187
00:27:28,242 --> 00:27:32,882
This family are the only orca
known to hunt rays like this...
188
00:27:34,522 --> 00:27:37,442
..and they are lethally efficient.
189
00:27:42,442 --> 00:27:46,722
But it appears that school
is over for today.
190
00:27:48,802 --> 00:27:51,402
For a few battle-scarred survivors,
191
00:27:51,442 --> 00:27:53,882
it's a lucky reprieve.
192
00:28:04,522 --> 00:28:09,322
With the orca gone, the rays
can resume their courtship...
193
00:28:17,682 --> 00:28:21,522
..and they do so
in astounding numbers.
194
00:28:30,722 --> 00:28:34,882
Tens of thousands of rays
in a single shoal.
195
00:28:50,242 --> 00:28:54,162
Vast areas of our ocean
are yet to be explored.
196
00:28:56,202 --> 00:29:00,482
The least known parts of it
are its great depths.
197
00:29:07,082 --> 00:29:11,322
Only highly-specialised vessels
can take you there.
198
00:29:16,682 --> 00:29:21,042
As you descend,
the sunlight rapidly fades.
199
00:29:27,402 --> 00:29:32,122
200m down,
you enter the twilight zone...
200
00:29:39,402 --> 00:29:43,922
..an alien world, inhabited
by creatures beyond imagination.
201
00:29:43,962 --> 00:29:45,562
..an alien world, inhabited
by creatures beyond imagination.
202
00:30:07,322 --> 00:30:12,602
A siphonophore - with a cloak
of lethal stinging tentacles.
203
00:30:12,642 --> 00:30:13,242
A siphonophore - with a cloak
of lethal stinging tentacles.
204
00:30:26,362 --> 00:30:30,362
Siphonophores repeatedly
clone themselves
205
00:30:30,402 --> 00:30:33,442
and so grow to immense lengths.
206
00:30:38,042 --> 00:30:42,322
This one measures 45m and is
the longest animal ever recorded.
207
00:30:42,362 --> 00:30:43,842
This one measures 45m and is
the longest animal ever recorded.
208
00:30:48,682 --> 00:30:50,922
With such deadly predators around,
209
00:30:50,962 --> 00:30:54,602
creatures here go
to great lengths to hide.
210
00:31:05,242 --> 00:31:07,682
A glass squid...
211
00:31:09,402 --> 00:31:12,202
..completely transparent,
212
00:31:12,242 --> 00:31:14,722
except for its eyes...
213
00:31:18,282 --> 00:31:21,562
..and stomach,
214
00:31:21,602 --> 00:31:25,442
so it is extremely difficult
to find in the gloom.
215
00:31:46,602 --> 00:31:49,522
Below 1,000m,
216
00:31:49,562 --> 00:31:53,242
all traces of sunlight
have disappeared.
217
00:31:55,442 --> 00:31:59,042
This is the midnight zone.
218
00:32:04,282 --> 00:32:08,842
Catching food in the perpetual
darkness is not easy.
219
00:32:29,802 --> 00:32:32,202
A gulper eel.
220
00:32:40,282 --> 00:32:42,482
Its giant, extendable mouth
221
00:32:42,522 --> 00:32:45,962
can engulf prey
larger than its own body.
222
00:33:09,482 --> 00:33:14,282
Two miles down,
you finally reach the ocean floor.
223
00:33:14,322 --> 00:33:14,522
Two miles down,
you finally reach the ocean floor.
224
00:33:20,202 --> 00:33:23,682
We know more
about the surface of Mars.
225
00:33:29,122 --> 00:33:33,402
The pressure of the water is 300
times greater than at the surface...
226
00:33:33,442 --> 00:33:35,162
The pressure of the water is 300
times greater than at the surface...
227
00:33:35,202 --> 00:33:37,602
..and it's freezing cold.
228
00:33:39,962 --> 00:33:44,882
Yet, amazingly,
there are animals living here.
229
00:33:50,282 --> 00:33:53,162
Muusoctopus robustus,
230
00:33:53,202 --> 00:33:56,442
nicknamed the pearl octopus.
231
00:33:59,482 --> 00:34:03,122
Breeding, in these
extreme conditions poses
232
00:34:03,162 --> 00:34:06,122
a particular problem
for these animals.
233
00:34:09,282 --> 00:34:11,562
At these low temperatures,
234
00:34:11,602 --> 00:34:15,882
this female's eggs could take
over ten years to develop.
235
00:34:15,922 --> 00:34:16,202
this female's eggs could take
over ten years to develop.
236
00:34:25,402 --> 00:34:29,602
So she travels
to a very special place.
237
00:34:43,802 --> 00:34:48,842
This is the largest known
gathering of octopus in the world.
238
00:34:48,882 --> 00:34:49,122
This is the largest known
gathering of octopus in the world.
239
00:34:59,002 --> 00:35:03,042
She joins 20,000 other females...
240
00:35:05,002 --> 00:35:07,882
..all here to lay their eggs.
241
00:35:14,402 --> 00:35:17,962
Water, heated deep
in the Earth's crust,
242
00:35:18,002 --> 00:35:21,242
rises through cracks
in the seabed...
243
00:35:23,162 --> 00:35:28,122
..raising the temperature
to as much as 10 degrees Celsius.
244
00:35:28,162 --> 00:35:28,402
..raising the temperature
to as much as 10 degrees Celsius.
245
00:35:29,842 --> 00:35:32,562
A deep-sea thermal spa!
246
00:35:37,682 --> 00:35:40,682
This warmth significantly speeds up
247
00:35:40,722 --> 00:35:43,842
the development of their eggs.
248
00:35:43,882 --> 00:35:47,922
Even so, they will still take
nearly two years to hatch.
249
00:35:50,202 --> 00:35:52,562
Once a female is settled,
250
00:35:52,602 --> 00:35:55,162
she won't move from her spot...
251
00:35:56,642 --> 00:35:59,122
..not even to feed.
252
00:36:10,762 --> 00:36:14,762
She will constantly tend
to her brood -
253
00:36:14,802 --> 00:36:17,642
keeping them clean,
254
00:36:17,682 --> 00:36:19,722
and oxygenating them
255
00:36:19,762 --> 00:36:22,322
with jets of water.
256
00:36:26,082 --> 00:36:30,842
Pearl octopus mothers must surely be
amongst the most devoted.
257
00:36:30,882 --> 00:36:31,122
Pearl octopus mothers must surely be
amongst the most devoted.
258
00:36:48,482 --> 00:36:53,122
After almost two years,
the ordeal take its toll.
259
00:36:53,162 --> 00:36:53,922
After almost two years,
the ordeal take its toll.
260
00:37:00,922 --> 00:37:03,682
But the vigil is almost over.
261
00:38:02,522 --> 00:38:06,802
The last of the brood
are gently encouraged to leave.
262
00:38:14,802 --> 00:38:17,802
But this will be a final act.
263
00:38:19,682 --> 00:38:24,522
Like all the mothers here, this
octopus is starved and exhausted.
264
00:38:24,562 --> 00:38:25,842
Like all the mothers here, this
octopus is starved and exhausted.
265
00:38:29,082 --> 00:38:32,002
Her life will soon be over.
266
00:38:50,082 --> 00:38:53,722
But this devotion means
that her offspring are among
267
00:38:53,762 --> 00:38:58,522
the largest and most developed
of any octopus
268
00:38:58,602 --> 00:39:01,242
and have the best chance of survival
269
00:39:01,282 --> 00:39:04,082
in the demanding world of the deep.
270
00:39:20,522 --> 00:39:24,802
We're finding more of these
strange hot springs every year.
271
00:39:35,762 --> 00:39:39,642
In some places,
they can be astonishingly violent.
272
00:39:41,162 --> 00:39:45,922
Super-heated water -
hot enough to melt lead -
273
00:39:45,962 --> 00:39:48,482
spouts from the seafloor.
274
00:39:50,122 --> 00:39:52,562
Dissolved minerals
condense around them
275
00:39:52,602 --> 00:39:56,962
to form towering chimneys,
known as hydrothermal vents.
276
00:39:57,002 --> 00:39:57,562
to form towering chimneys,
known as hydrothermal vents.
277
00:40:02,042 --> 00:40:05,842
They are home to unique
communities of animals
278
00:40:05,882 --> 00:40:09,602
that all rely on the nutrients
in the scalding water.
279
00:40:19,642 --> 00:40:23,402
Some suggest that vents
like these could be the places
280
00:40:23,442 --> 00:40:27,642
where life on Earth first began
four billion years ago.
281
00:40:35,722 --> 00:40:38,722
And there is now evidence
of hydrothermal vents
282
00:40:38,762 --> 00:40:41,802
on the moons of Jupiter and Saturn.
283
00:40:43,762 --> 00:40:46,482
Could they too be supporting life?
284
00:40:51,242 --> 00:40:55,442
Here on Earth,
the influence of these vents
285
00:40:55,482 --> 00:40:58,402
extends far beyond their chimneys.
286
00:41:00,162 --> 00:41:03,402
The essential nutrients
carried in these plumes
287
00:41:03,442 --> 00:41:08,162
can rise all the way to the surface
two miles above.
288
00:41:08,202 --> 00:41:08,322
can rise all the way to the surface
two miles above.
289
00:41:13,962 --> 00:41:18,722
Here, they stimulate the rapid
growth of tiny marine plants...
290
00:41:18,762 --> 00:41:21,402
..on an astronomic scale.
291
00:41:28,162 --> 00:41:31,602
This phytoplankton is so abundant
292
00:41:31,642 --> 00:41:35,842
that it produces half
of all the oxygen on Earth.
293
00:41:54,042 --> 00:41:58,522
It's also food for a host
of minute animals -
294
00:42:00,042 --> 00:42:02,322
zooplankton.
295
00:42:04,202 --> 00:42:07,842
Together, they are the basis
of the food chains
296
00:42:07,882 --> 00:42:10,922
that sustain
nearly all life in the ocean.
297
00:42:16,682 --> 00:42:20,082
In the Pacific waters
off South America,
298
00:42:20,122 --> 00:42:24,642
they feed anchovy
that gather here in billions.
299
00:42:24,682 --> 00:42:25,002
they feed anchovy
that gather here in billions.
300
00:42:38,402 --> 00:42:42,642
This is one of the world's
most productive ecosystems.
301
00:42:54,402 --> 00:42:58,002
These South American
sea lions are on the hunt.
302
00:43:18,402 --> 00:43:23,082
But the anchovy shoal
has already been located...
303
00:43:23,122 --> 00:43:23,202
But the anchovy shoal
has already been located...
304
00:43:27,882 --> 00:43:31,202
..by the planet's
most efficient hunters.
305
00:43:34,602 --> 00:43:37,322
A net, over half a mile long,
306
00:43:37,362 --> 00:43:39,282
encircles the shoal.
307
00:43:42,322 --> 00:43:45,322
It can trap over a million fish.
308
00:43:57,362 --> 00:44:00,122
But the sea lions
aren't about to go hungry.
309
00:44:02,562 --> 00:44:06,042
They have learnt
to look for holes in the net.
310
00:44:16,682 --> 00:44:21,522
Why waste energy when food
comes to you as easily as this?!
311
00:44:21,562 --> 00:44:23,162
Why waste energy when food
comes to you as easily as this?!
312
00:44:29,882 --> 00:44:33,122
As more and more sea lions arrive,
313
00:44:33,162 --> 00:44:35,642
some change their tactics.
314
00:44:43,282 --> 00:44:46,242
They line up
on both sides of the net...
315
00:44:47,922 --> 00:44:49,722
..and wait.
316
00:45:04,562 --> 00:45:09,322
As the net tightens, the anchovy
panic and rush for the surface.
317
00:45:09,362 --> 00:45:09,402
As the net tightens, the anchovy
panic and rush for the surface.
318
00:45:15,882 --> 00:45:19,882
This is the moment the sea lions
have been waiting for.
319
00:45:34,242 --> 00:45:38,002
It's such an effective way
of hunting that the sea lions here
320
00:45:38,042 --> 00:45:40,762
are changing
their natural behaviour...
321
00:45:43,962 --> 00:45:47,762
..and are raiding the fishing nets
322
00:45:47,802 --> 00:45:50,162
in their thousands.
323
00:45:57,882 --> 00:46:00,122
With the net almost drawn in,
324
00:46:00,162 --> 00:46:03,362
the fishermen beat out
a warning signal.
325
00:46:06,882 --> 00:46:08,842
Time is up.
326
00:46:38,322 --> 00:46:42,322
In the confusion,
not everyone manages to escape.
327
00:46:51,002 --> 00:46:55,482
The trapped sea lions are in danger
of being drowned.
328
00:47:17,202 --> 00:47:20,882
Pups are separated
from their mothers.
329
00:48:24,722 --> 00:48:29,082
Then, at the last minute, the
fishermen briefly drop their net...
330
00:48:29,122 --> 00:48:29,362
Then, at the last minute, the
fishermen briefly drop their net...
331
00:48:36,842 --> 00:48:39,882
..and the trapped sea lions
can escape.
332
00:48:48,202 --> 00:48:51,402
But many are not so lucky.
333
00:48:53,362 --> 00:48:57,762
Around the world, millions
of animals are accidently caught
334
00:48:57,802 --> 00:48:58,322
Around the world, millions
of animals are accidently caught
335
00:48:58,362 --> 00:49:02,402
and die in fishing nets every day.
336
00:49:04,842 --> 00:49:08,682
And this by-catch, as it's known,
337
00:49:08,722 --> 00:49:12,002
is pushing many species
toward extinction.
338
00:49:16,962 --> 00:49:20,242
Animals have evolved
in remarkable ways
339
00:49:20,282 --> 00:49:22,882
to the demands of life in the ocean.
340
00:49:27,642 --> 00:49:30,562
But can they now adapt
to the new challenge -
341
00:49:31,882 --> 00:49:34,362
living alongside us?
342
00:49:51,642 --> 00:49:54,722
The open ocean is home
to some of the largest
343
00:49:54,762 --> 00:49:57,402
and most extraordinary animals
on Earth.
344
00:49:59,882 --> 00:50:02,162
But here, off the Canary Islands,
345
00:50:02,202 --> 00:50:05,682
the Planet Earth team are searching
for one of its smaller,
346
00:50:05,722 --> 00:50:08,362
and less familiar residents.
347
00:50:08,402 --> 00:50:10,922
We're looking for a tiny creature
called a Columbus crab,
348
00:50:10,962 --> 00:50:13,082
which is only about the size
of your thumbnail,
349
00:50:13,122 --> 00:50:16,762
which live on floating objects
in the open ocean.
350
00:50:16,802 --> 00:50:20,042
Columbus crabs were once
only found on natural debris,
351
00:50:20,082 --> 00:50:22,162
like driftwood or seaweed,
352
00:50:22,202 --> 00:50:24,202
but the oceans are changing,
353
00:50:24,242 --> 00:50:26,362
and they've been forced to adapt.
354
00:50:40,882 --> 00:50:45,082
One of the most common items
they find is discarded fishing gear.
355
00:50:45,122 --> 00:50:45,162
One of the most common items
they find is discarded fishing gear.
356
00:50:47,562 --> 00:50:52,522
Over a million tons is left adrift
in the ocean each year.
357
00:50:52,562 --> 00:50:52,762
Over a million tons is left adrift
in the ocean each year.
358
00:50:54,402 --> 00:50:57,122
And Columbus crabs are now
making their homes
359
00:50:57,162 --> 00:50:59,642
on these unnatural materials.
360
00:51:07,202 --> 00:51:10,442
Surprisingly, Columbus crabs
are thriving on this new habitat.
361
00:51:15,802 --> 00:51:20,122
But, for larger ocean creatures,
these nets can be lethal.
362
00:51:20,162 --> 00:51:20,602
But, for larger ocean creatures,
these nets can be lethal.
363
00:51:22,722 --> 00:51:26,322
Loggerhead sea turtles
are especially vulnerable.
364
00:51:29,962 --> 00:51:33,362
Many times, they are very injured
365
00:51:33,402 --> 00:51:37,202
and many times
they don't even survive.
366
00:51:37,242 --> 00:51:39,762
It's a sad situation.
367
00:51:41,242 --> 00:51:45,162
As a rule, wildlife film-makers
observe natural behaviour
368
00:51:45,202 --> 00:51:47,242
and do not interfere.
369
00:51:50,922 --> 00:51:54,242
But this is far from natural.
370
00:51:54,282 --> 00:51:57,682
The team feel they must take action.
371
00:52:07,242 --> 00:52:10,042
Sh...
372
00:52:10,082 --> 00:52:12,402
It seems that the turtle
is quite OK.
373
00:52:12,442 --> 00:52:17,002
We'll just finish to cut
the plastic and then we release it.
374
00:52:33,522 --> 00:52:35,682
It's a bittersweet moment,
375
00:52:35,722 --> 00:52:40,882
as this is one of eight turtles
they rescued whilst filming here.
376
00:52:40,922 --> 00:52:44,242
This situation is not natural,
377
00:52:44,282 --> 00:52:48,002
it's something that is
being caused by human beings.
378
00:52:49,642 --> 00:52:53,002
Sadly, the crew now face
dilemmas like this
379
00:52:53,042 --> 00:52:56,362
on many of their
filming expeditions...
380
00:52:58,442 --> 00:53:02,522
..including, when they travelled
to the Pacific coast of Chile,
381
00:53:02,562 --> 00:53:05,482
to show how sea lions
are competing for food
382
00:53:05,522 --> 00:53:08,042
with one of the biggest fisheries
on Earth.
383
00:53:13,162 --> 00:53:17,842
Expedition leader Fernando Olivares
takes the team to the fleet.
384
00:53:25,122 --> 00:53:28,722
Diving near fishing nets
is extremely dangerous,
385
00:53:28,762 --> 00:53:32,202
so the crew must ensure they have
the full cooperation
386
00:53:32,242 --> 00:53:34,162
of the fishermen.
387
00:53:58,642 --> 00:54:01,682
Pretty hazardous place to dive.
388
00:54:01,722 --> 00:54:04,002
It's just a case of trying
to keep an eye on the divers,
389
00:54:04,042 --> 00:54:06,562
but the sea lions also like
to go down and blow bubbles,
390
00:54:06,602 --> 00:54:08,362
so you'll think
you're following the divers,
391
00:54:08,402 --> 00:54:10,682
and then a sea lion will pop up.
392
00:54:16,322 --> 00:54:18,402
Taking the utmost care,
393
00:54:18,442 --> 00:54:20,482
the divers get a close-up view
394
00:54:20,522 --> 00:54:23,042
of the sheer scale of the operation.
395
00:54:29,042 --> 00:54:32,562
This one net must have
about 15 tons of fish in it
396
00:54:32,602 --> 00:54:35,642
and there's eight or nine boats
in this one little bay,
397
00:54:35,682 --> 00:54:37,402
and these are just the small boats.
398
00:54:37,442 --> 00:54:39,402
Out there, there are huge
factory ships that are taking
399
00:54:39,442 --> 00:54:41,562
even bigger catches.
400
00:54:42,842 --> 00:54:45,242
How much fish a year from just here?
401
00:54:45,282 --> 00:54:49,002
From a million tons a year
more or less.
402
00:54:57,082 --> 00:54:59,722
The catches are so vast,
403
00:54:59,762 --> 00:55:02,842
the sea lions have changed
their natural behaviour
404
00:55:02,882 --> 00:55:06,082
to collect anchovies
directly from the nets.
405
00:55:10,322 --> 00:55:12,322
But it's a risky strategy.
406
00:55:13,962 --> 00:55:17,842
The crew witnessed sea lions
caught in nets multiple times.
407
00:55:18,962 --> 00:55:22,042
Whoa, it's intense mate,
there are so many in there.
408
00:55:28,362 --> 00:55:30,882
There's a pup stuck in the net,
calling to its mother,
409
00:55:30,922 --> 00:55:33,882
and its mother's just on the outside
of the net calling back.
410
00:55:40,202 --> 00:55:42,762
That's really hard to watch.
411
00:55:48,362 --> 00:55:50,562
Oh, the pup's really panicking now.
412
00:55:53,122 --> 00:55:57,442
Sometimes, fishermen are able
to release trapped sea lions...
413
00:55:57,482 --> 00:55:57,602
Sometimes, fishermen are able
to release trapped sea lions...
414
00:55:58,922 --> 00:56:01,042
..but not this time.
415
00:56:03,402 --> 00:56:05,722
The pup is in serious danger.
416
00:56:07,882 --> 00:56:11,482
Once again,
the crew decide to step in.
417
00:56:13,442 --> 00:56:16,642
Hey, he's going to go
inside of the net to save him.
418
00:56:40,362 --> 00:56:42,562
Wow.
419
00:56:46,442 --> 00:56:50,322
Nice, really nice.
420
00:56:50,362 --> 00:56:52,442
It's a relief this time...
421
00:56:55,002 --> 00:57:00,122
..but it highlights the new
realities of filming wildlife
422
00:57:00,162 --> 00:57:00,402
..but it highlights the new
realities of filming wildlife
423
00:57:00,442 --> 00:57:04,042
in today's changing ocean.
424
00:57:13,162 --> 00:57:17,402
Next time, a journey to Earth's
greatest wilderness -
425
00:57:21,162 --> 00:57:24,722
deserts and grasslands...
426
00:57:30,322 --> 00:57:33,682
..where nature puts on
its most dramatic show.
427
00:57:36,642 --> 00:57:40,762
Habitat Explorer brings animals
and their habitats to life.
428
00:57:40,802 --> 00:57:44,322
Explore this free interactive
and make origami animals.
429
00:57:44,362 --> 00:57:48,442
Go to...
430
00:57:48,482 --> 00:57:50,802
And follow the links
to the Open University.
431
00:57:50,842 --> 00:57:53,042
Or to order a free printed version,
432
00:57:53,082 --> 00:57:56,722
visit the website
or call the numbers on the screen.
36673
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.