1. In the course of making Blue Planet II,
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2. we've explored every corner
of the underwater world.
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3. We've encountered extraordinary animals,
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4. and discovered new insights into
how life is lived beneath the waves.
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5. For years we thought
that the oceans were so vast
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6. and the inhabitants
so infinitely numerous
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7. that nothing we could do
could have an effect upon them.
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8. But now we know that was wrong.
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9. The oceans are under threat now
as never before in human history.
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10. In this final episode,
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11. we will meet the pioneers
who are striving to turn things around.
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12. People who are helping to save
the Ocean's most vulnerable inhabitants
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13. and dedicating their lives
to protecting the seas.
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14. But is time running out?
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15. Many people believe that our oceans
have reached a crisis point.
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16. So just how fragile is our blue planet?
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17. Winter in the Arctic Circle.
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18. Every year, the waters of Norway
are the setting
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19. for one of the greatest
wildlife spectacles in the ocean.
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20. Over a billion herring
pour into these fields.
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21. The Blue Planet II team
spent three years
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22. documenting this astonishing event.
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23. Such a wealth of prey attracts predators
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24. in extraordinary numbers.
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25. Orcas
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26. and humpback whales.
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27. But this migration
hasn't always been so bountiful.
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28. Leif Notastad is a Norwegian
fisheries scientist.
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29. It's been one of
the most important fisheries
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30. that we had for centuries
along the whole coast of Norway.
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31. But in the late 19605
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32. the herrings that we see around us here
was on the brink of Collapse.
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33. 50 years ago, fishing was so intensive
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34. that the herring had all
but disappeared.
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35. Orcas were seen as rivals
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36. and hundreds of them were killed.
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37. It was only after the Norwegian
government imposed severe restrictions
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38. that the herring began to recover.
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39. Today, this is once again
an immensely productive fishery,
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40. closely monitored
by teams of scientists.
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41. Marine biologist Eve jourdain
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42. is one of the resident orca experts.
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43. From 1982, orcas got protected in Norway
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44. and we have clearly one of the largest
orca population in the world out here.
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45. There are now over
a thousand orcas here.
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46. But with so many mouths to feed,
including ours,
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47. can the mistakes of the past be avoided?
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48. To answer this vital question,
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49. Eve and her team are using
multi sensor camera tags.
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50. With the tags we try to see
how the orcas interact with their prey.
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51. How they hunt and all about
the underwater behaviour
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52. that we are not able to see
from the boat.
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53. A tag has to be attached
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54. to the orca in
exactly the right position.
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55. Here it goes. Here it comes.
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56. oh, that's a good shot.
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57. It is the least invasive method.
It is suction cups.
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58. So it is not a Scratch
on the whale afterwards
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59. which is something we really like.
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60. While studying the orcas,
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61. Eve noticed a worrying change
in their behaviour.
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62. They had worked out
the easiest way to get a meal.
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63. We have seen that the orcas are waiting
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64. for those fishing boats to drop the net.
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65. It acts like a dinner bell
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66. and then all the orcas
of the area gather.
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67. Quite a lot of herring slip from the net
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68. and this is exactly what
the orcas are looking for.
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69. But this new tactic
is dangerous, as Eve has witnessed.
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70. We were there to monitor
the behaviour of the orcas
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71. scavenging around the nets.
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72. And we realised that
one large adult male
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73. was actually trapped inside the net.
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74. When the fishermen
started to retrieve the net
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75. the orca was obviously starting to panic
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76. and trying to pull as much as he could.
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77. This orca was really fighting
for his life.
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78. Stringent rules require fishermen
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79. to get permission
before they open their nets.
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80. But that took time.
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81. It was such a long process.
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82. We thought that the whale
was going to die of exhaustion.
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83. Thankfully, the fishermen
finally got the clearance
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84. to release their net
freeing the exhausted orca.
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85. It was a huge relief to see that
this orca made it until the end
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86. and finally got back to his family.
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87. With marine mammals
and humans competing so directly
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88. accidents are inevitable.
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89. Two days after tagging an orca,
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90. it's released and Eve collects it.
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91. This tag is full of secrets, you know,
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92. because it has been on
the whale for several days
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93. and will just reveal exactly
what the whales have been doing.
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94. Pictures from the tag
reveal the hunting technique in detail.
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95. They dive below the ball of fish
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96. and then back flip.
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97. The tail slap stuns the herring.
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98. Eve can even work out
how many fish the orcas are taking.
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99. They can kill up to 30 herring
with just one tail slap.
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100. And then what is pretty amazing is
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101. all the individuals of the group
share the dead herring.
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102. And it's not just
the orcas feeding here...
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103. Humpback whales
are also drawn to the feast.
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104. They too are being tagged and monitored
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105. giving fishery scientist Leif
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106. a complete picture of
how much herring is being eaten.
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107. The whales, they take
probably less than 1%.
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108. The fishermen take less than 10%.
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109. So the balance there is that
there is enough for everybody.
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110. Given that we manage to stock
in sustainable
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111. and a long term sustainable way.
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112. But it's estimated that
almost a third of ocean fisheries
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113. are being over exploited.
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114. The remarkable recovery
of the herring here
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115. demonstrates what can happen
if a fishery is carefully managed.
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116. Our maltreatment of the seas
has many effects.
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117. Some are predictable,
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118. but there are others
that are rather more surprising.
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119. Southeast Asia.
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120. The coral reefs here are among
the richest on the planet.
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121. Marine biologist Steve Simpson,
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122. is discovering how important sound is
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123. to the animals that live in these
bustling coral cities.
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124. We're only now just realising
by listening underwater
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125. that the fish are making
all these sounds.
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126. They use sound to attract a mate.
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127. To try and scare away a predator.
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128. You hear pops and grunts
and gurgles and snaps.
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129. There's a whole language underwater
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130. that we're only just starting
to get a handle on.
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131. Using an advanced
multi directional hydrophone,
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132. Steve is trying to make sense
of this extraordinary chorus
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133. by working out who is making
which noise.
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134. One fish is especially talkative.
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135. It's perhaps the reef's
most famous resident.
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136. The clownfish.
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137. While filming for the series,
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138. we followed this particular family
of saddleback clownfish
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139. as they search for a suitable place
to lay their eggs.
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140. It's a noisy affair.
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141. For clownfish sound
really is everything.
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142. They spend all day
talking to each other.
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143. You've got dominance and submission.
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144. You've got all the others
calling to each other.
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145. It seems that they also use sound
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146. in protecting themselves from the many
predators that hunt around the reef.
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147. Including coral trout.
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148. Will this model trout
fool the clownfish?
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149. They react almost immediately.
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150. By mimicking a predator,
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151. Steve manages to record their alarm
calls without putting them at risk.
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152. You can really hear the deeper
pulsing sound of the female
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153. as she tries to scare
the coral trout away.
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154. And all the little ones are
just popping... Pop, pop, pop.
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155. As if to say, "I'm still okay.
I'm still alive."
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156. So they've got this real language
of sounds that they're using
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157. just to try and defend the colony
against this coral trout.
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158. But that discovery
has led to a serious worry.
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159. The fish were really
popping away at the predator.
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160. But as soon as the boat came over
they looked completely distracted.
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161. With all that noise it completely
changed how the fish were behaving.
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162. Unable to make themselves
heard above the noise of boats,
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163. the family can't warn each other
of danger.
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164. And so they are now
vulnerable to attack.
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165. You think about how many boats
are driving around.
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166. All of the ships,
all of the offshore drilling.
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167. All the noise that we're making
in the ocean
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168. you realise just how much
we're drowning out
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169. this natural biological noise,
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170. robbing animals of their ability to be
able to talk to each other.
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171. All this noise may have
serious consequences for many reef fish
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172. because their babies, as soon as they
hatch are swept out to sea.
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173. There they feed and grow
until strong enough to swim back.
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174. And to find the reef, they use sound.
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175. They listen in. They eavesdrop
to the noises that they can hear
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176. and they use that to choose which reef
they want to make their home.
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177. But obviously because we're adding
all this noise to the ocean
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178. it's a wonder whether they can even
hear the reef at all.
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179. Man-made noise is now
everywhere in the ocean.
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180. And it has an effect on
marine creatures of all kinds.
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181. From tiny fish
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182. to gigantic whales.
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183. But Steve believes there are solutions.
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184. Noise in the ocean is a real problem.
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185. But, it's something that we can control.
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186. We can choose where we make the noise.
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187. We can choose when we make the noise.
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188. We can directly reduce
the amount of noise that we make
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189. and we can start doing that today.
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190. We're only now beginning to realise
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191. what an impact our noise is having
on the inhabitants of the ocean.
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192. Other forms of pollution
are only too familiar.
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193. Since its invention some
hundred years ago,
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194. plastic has become an integral part
of our daily lives.
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195. But every year,
some eight million tons of it
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196. ends up in the ocean.
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197. And there, it could be lethal.
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198. While filming Blue Planet II,
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199. the crews found plastic in every ocean.
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200. Even in the most remote locations.
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201. South Georgia.
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202. 900 miles north of Antarctica,
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203. this isolated Wilderness
is the breeding place
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204. for vast numbers of penguins
and elephant seals.
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205. It's also a favourite nesting site
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206. for the largest bird in the sky.
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207. A wandering albatross.
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208. Here we learn of
the extraordinary lengths
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209. ancient parents go to give their chicks
the best chance of survival.
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210. Each devoted parent travels thousands
of miles searching for fish and squid
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211. to feed their hungry chick.
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212. But despite all their efforts,
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213. the albatross colony here is in trouble.
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214. Lucy Quinn is part of
the British Antarctic Survey team
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215. studying the birds here
for the last 40 years.
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216. Its only through looking at
long terms studies
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217. that you get a sense of these creatures.
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218. And the albatrosses here have,
over the past 10 years, been in decline.
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219. There are a number of possible reasons.
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220. While foraging at sea,
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221. albatross can get entangled
and drowned by fishing gear.
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222. But Lucy is particularly alarmed
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223. by what the parents are bringing back
for their chick.
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224. Albatrosses have the ability to cough up
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225. bits of food that they can't digest.
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226. And from that we can tell
what they've been eating.
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227. A healthy albatross chick in its diet
should really have things like squid.
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228. So we can find the squid beaks
that come out of the pellet.
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229. And also things like fish
so we can find fish bones as well.
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230. But these chicks are being
fed something very different.
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231. We have some plastic that
this poor chick has had to bring up.
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232. Plastic bag.
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233. Here we have some food packaging.
Looks like rice.
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234. Luckily for this chick, he has managed
to get this out of his stomach.
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235. So, fingers crossed he doesn't have
any more plastic left in there
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236. before he fledges.
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237. For other chicks, plastic can be fatal.
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238. Unfortunately,
there is a plastic toothpick
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239. that have actually gone through
the stomach.
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240. Something just as small as that has
actually has managed to kill the bird.
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241. It's really sad to see.
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242. Lucy collects and records
what plastic she finds around the nests.
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243. These are items that were
regurgitated just from last season.
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244. And that's gonna be
a vast underestimation
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245. because that's just ones
that we happen to find.
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246. There'll be many more that
we never see being brought back.
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247. To find out where
all this rubbish is coming from,
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248. Lucy and her team have attached
GPS trackers to adult birds.
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249. It's showing where they're
going to find food for themselves
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250. and to find food to bring back
for their chicks.
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251. It really shows us that
they could be picking up plastic
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252. from thousands of miles away.
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253. Plastics coming from either being
dumped at sea
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254. or also from people's homes.
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255. Plastic gets into the rivers and then
the rivers flow into the sea.
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256. So this isn't just a problem
around these remote parts.
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257. This is happening worldwide.
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258. And it's our rubbish
that's going into the oceans.
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259. It's our problem that we need to solve.
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260. In some parts of the ocean,
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261. it's estimated that there are now over
one million pieces of plastic
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262. for every square mile.
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263. And we're only beginning to discover
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264. just how seriously
that affects marine life.
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265. On the east coast of the United States,
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266. researchers are investigating
the mysterious deaths of young dolphins.
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267. The team is led by Dr Leslie Hart.
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268. It looks to be a young animal.
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269. Maybe a little bit over a year.
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270. So we're gonna try to find out more
information on why this dolphin died.
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271. Looking at young dolphins...
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272. The very young dolphins,
it's always heart-breaking.
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273. Leslie takes tissue samples.
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274. Their chemical analysis
could provide crucial evidence.
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275. We are often shocked
by the high levels of toxins
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276. that we detect in these animals.
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277. These young calves are dying
for a number of reasons.
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278. But we suspect man-made toxins
are playing a large role.
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279. And plastic could be
part of the problem.
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280. Once in the ocean,
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281. plastic breaks down into tiny fragments.
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282. Micro plastics.
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283. Along with all the industrial chemicals
that have drained into the ocean
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284. these form a potentially toxic soup.
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285. The really small organisms
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286. can mistake these tiny,
tiny plastics as food.
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287. Then the larger organisms
eat the plankton.
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288. Then the larger fish
eat the smaller fish,
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289. and so on and so forth.
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290. Dolphins are
at the top of this food chain
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291. and it's now thought that pollutants
may be building up in their tissues
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292. to such a degree that a mother's
contaminated' milk could kill her calf.
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293. Industrial pollution
and the discarding of plastic waste
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294. must be tackled for the sake of
all life in the ocean.
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295. Around the world,
people are now devoting their lives
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296. to saving some of the most
threatened sea creatures.
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297. As here in the Caribbean.
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298. Every year on just a few islands,
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299. a remarkable event takes place.
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300. As the sun sets,
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301. giant reptiles begin to emerge.
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302. This magnificent creature preparing...
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303. Whoops.
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304. Preparing to lay her eggs
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305. is the largest of all turtles.
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306. A leatherback.
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307. They can grow up to
half a ton in weight.
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308. And they have an ancestry that
goes back a hundred million years
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309. to the age of the dinosaur.
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310. But in recent times their numbers
have fallen catastrophically.
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311. Here, however, in the Caribbean
there is hope.
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312. Leatherback turtles leave the sea
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313. in order to lay their eggs
in the dry sand.
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314. But out of water, these huge creatures
are easy targets for hunters.
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315. In a small fishing village in Trinidad,
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316. Len Peters has experienced this
first hand.
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317. I grew up in a household where
the presence of turtle meat was normal.
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318. The fridge was always full of it.
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319. Everybody... Everybody harvested
turtles, including my parents.
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320. It's only when I became
exposed to things
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321. that were being published
about leatherbacks
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322. who were on the verge of extinction.
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323. And nobody cares.
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324. That piqued my interest.
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325. Len took the leatherback's
future into his own hands.
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326. He began patrolling the beach at night
to protect the turtles.
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327. A brave thing to do.
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328. We were met with tremendous resistance.
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329. People would pelt us at night.
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330. I have had persons insult me.
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331. I've had persons curse me.
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332. I've had persons physically
try to wrestle me with a machete.
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333. So it was really
a hostile time back then.
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334. If Len was going to save these turtles
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335. he needed to win over
the whole community.
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336. We had to find a way to
get the villagers to benefit
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337. from the presence of these animals.
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338. He began to encourage
tourists to visit the beach
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339. and trained some villagers
to be their guides.
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340. To help secure the turtle's future,
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341. he took the message
to the next generation.
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342. Now what's... What's the largest size
a leatherback can grow to?
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343. Uh, Shame.
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344. - 2,000 pounds.
- That's correct.
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345. Leatherbacks can grow to 2,000 pounds.
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346. Well, that's a big turtle.
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347. Len's hard work paid off.
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348. And now, attitudes have changed.
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349. It took us a while to
reach out to the villagers.
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350. But gradually we got them
involved as well.
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351. We got some of the poachers who
would be hunting the animals to
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352. be part of the conservation programme.
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353. As well as protecting the adult turtles,
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354. the team also collect any eggs
that might be flooded at high tide.
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355. If the eggs are laid
too close to the sea,
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356. we relocate the eggs and rebury them.
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357. Thanks to the efforts of this community,
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358. these turtles have had an extraordinary
change in fortune.
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359. This is now thought to be
one of the densest
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360. leatherback nesting beaches
in the world.
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361. When we started at the height
of the nesting season,
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362. the numbers will be 30-40 turtles
a night.
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363. Now, it's over 500.
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364. So, we have seen an increase
from 40 turtles
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365. to 500 turtles a night
in just around 20 years.
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366. Precious new hatchlings
are also given a helping hand.
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367. Any that emerge during the day
are collected
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368. to be released safely back to the sea,
away from hungry birds.
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369. This little leatherback will have to
face a thousand hazards
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370. before it returns as an adult
to this beach where it hatched.
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371. And those dangers will be
greatly increased
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372. because of damage that we have done
to the ocean.
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373. Good luck, little leatherback.
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374. Protecting breeding sites on beaches
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375. may improve the fortune
of some marine animals,
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376. but safeguarding them while they roam
the high seas is much more difficult.
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377. Out here, there is little protection.
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378. Every night, thousands of miles of
fishing lines laden with hooks are set.
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379. There's enough, it's said,
to wrap twice around the world.
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380. Nets large enough to engulf cathedrals
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381. trap hundreds of tons of fish at a time.
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382. Long distance travellers such as sharks
are particularly at risk.
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383. It's estimated that tens of millions
are killed every year,
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384. including the biggest fish in the sea,
the whale shark.
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385. Shark biologist Jonathan Green
is concerned
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386. that time is running out
for these extraordinary creatures.
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387. We know that they're being fished
possibly at a massive rate.
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388. They may be taken by the thousands,
possibly tens of thousands a year.
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389. If that is indeed true,
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390. we don't know how long they can
withstand that kind of fishing pressure.
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391. To save them,
Jonathan is flying to solve
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392. the mystery of where they give birth.
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393. And, for the first time, he has a clue
as to where this might be.
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394. Pregnant whale sharks are thought to be
travelling from across the Pacific Ocean
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395. to Darwin Island in the Galapagos.
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396. Jonathan is going to try and attach
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397. a multi-sensor camera tag
to a pregnant female.
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398. Okay. We're good to go.
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399. These sharks only stay in the area
for a few days.
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400. This may be his only chance.
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401. Jonathan has to attach the tag before
the shark dives to dangerous depths.
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402. The tag will remain on the giant's fin
for two days
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403. before it's automatically released.
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404. Once retrieved, it reveals
some unusual behaviour.
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405. Oh, beautiful, beautiful.
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406. There's a silky rubbing at the in front.
Next to her right.
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407. The silky sharks are
brushing up against her rough skin,
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408. perhaps to scrape off parasites.
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409. These predatory sharks make the surface
waters very unsafe places
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410. for young fish of any kind.
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411. There is a surprise in store.
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412. The tag's depth sensor reveals
that she dived
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413. to a depth of 600 metres.
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414. But down there,
it's too dark for the camera.
Copy !req
415. The only way Jonathan can prove
if they're giving birth
Copy !req
416. is to go down and look.
Copy !req
417. Out of the gloom, a shape materialises.
Copy !req
418. Another massive whale shark.
Copy !req
419. Oh, look at her. She's having a look
at us. She's looking right at us.
Copy !req
420. She is huge.
Copy !req
421. And look at the belly.
Absolutely massive.
Copy !req
422. That's a large pregnant female.
Copy !req
423. She's turning around.
She's turning around.
Copy !req
424. Goes to show we can follow them.
We can follow them in the submarine.
Copy !req
425. She leads them down into the darkness.
Copy !req
426. Rover control.
Passing 100 metres, descending.
Copy !req
427. Heading down.
I think she's accelerated slightly.
Copy !req
428. She's too fast.
Copy !req
429. And with the strong current running
against them, the sub can't keep up.
Copy !req
430. But, for the first time,
Jonathan can see for himself
Copy !req
431. exactly where she's headed.
Copy !req
432. What specifically Darwin could provide
Copy !req
433. is a safe refuge for those new-born pups
where predators can't access.
Copy !req
434. Perfect conditions
for the formative years
Copy !req
435. of these ocean-travelling giants.
Copy !req
436. That was unbelievable.
Copy !req
437. Dream of a lifetime.
Copy !req
438. His discovery that pregnant whale sharks
Copy !req
439. are visiting this very deep patch
of the sea floor
Copy !req
440. is strong evidence that this is indeed
where the giants produce their young.
Copy !req
441. If I can actually prove
that they are giving birth in this area,
Copy !req
442. then we'll have
the information necessary
Copy !req
443. to go to governments and actually say,
Copy !req
444. "You must preserve those routes
that they're migrating through."
Copy !req
445. And then, and only then,
can we really truly afford protection
Copy !req
446. for this beautiful ocean traveller.
Copy !req
447. Today, less than one percent
Copy !req
448. of our international waters
are protected.
Copy !req
449. And the creation of marine reserves
is vital
Copy !req
450. if we're to safeguard the future
of many ocean creatures.
Copy !req
451. It will require
international cooperation.
Copy !req
452. But here, too, there is hope.
Copy !req
453. We can turn things around.
Copy !req
454. We've done so once before.
Copy !req
455. For centuries,
the sea-going nations of the world
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456. hunted the great whales
until they were close to extinction.
Copy !req
457. And then, in 1986,
those nations got together
Copy !req
458. and agreed to put a stop
to commercial whaling.
Copy !req
459. Today, although a few nations
continue to hunt whales,
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460. some of the great whales
are making a recovery.
Copy !req
461. In the tropical seas
surrounding Sri Lanka,
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462. there are stories of vast gatherings
of whales.
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463. When the civil war ended in 2009,
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464. locals here were able once again
to fish these waters.
Copy !req
465. There were soon reports of assemblies
of sperm whales,
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466. the likes of which had not been seen
for centuries.
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467. Marine guide Daya was determined
to get to the truth
Copy !req
468. behind these fishermen's tales.
Copy !req
469. The fishermen told me that
there are lots of whales
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470. a little bit north from here.
Copy !req
471. They didn't actually tell me a number,
Copy !req
472. but in big numbers, not one or twos.
Copy !req
473. Er, many.
Copy !req
474. It took him three years,
Copy !req
475. but eventually, he found evidence
to support these rumours.
Copy !req
476. We saw about 15 sperm whales go past us.
Copy !req
477. Then, another four came past us.
Copy !req
478. After about 40 then passed me,
I started counting.
Copy !req
479. Still, they kept coming,
so I lost count.
Copy !req
480. I estimated that we saw about
300 sperm whales.
Copy !req
481. Sperm whales were once
killed in vast numbers
Copy !req
482. and it's thought that if the slaughter
had continued,
Copy !req
483. the species would be in danger
of extermination.
Copy !req
484. But now, here at least,
they are being seen in huge numbers.
Copy !req
485. I believe they come here to feed,
mate, and raise their young.
Copy !req
486. So, this must be a holiday spot
for them, you know.
Copy !req
487. At the moment, I don't know
of any other place in the world
Copy !req
488. that, er, sperm whales gather like this.
Copy !req
489. Although some whale
populations are still in decline,
Copy !req
490. scenes like this prove that when
sea-going nations come together,
Copy !req
491. they can achieve astonishing results.
Copy !req
492. But today, the oceans face threats
on a truly global scale.
Copy !req
493. The Great Barrier Reef.
Copy !req
494. The largest coral reef system
in the world.
Copy !req
495. Here, we filmed stories which reveal
just how smart fish can be.
Copy !req
496. This ingenious tuskfish, for example,
Copy !req
497. used a favourite coral anvil
to smash open shellfish.
Copy !req
498. This astonishing behaviour
has been closely studied
Copy !req
499. by local scientist Alex Vail.
Copy !req
500. We're calling Percy
"Percy the Persistent"
Copy !req
501. because he took, like, an hour
to open the first shell.
Copy !req
502. He must have hit it well over 50 times,
Copy !req
503. but he just kept on going
and finally got it open.
Copy !req
504. Alex grew up on the Great Barrier Reef
Copy !req
505. on one of its more remote islands,
Lizard.
Copy !req
506. He knows the reef intimately.
Copy !req
507. But, in 2076, while he was filming
for Blue Planet II,
Copy !req
508. Alex witnessed a catastrophe.
Copy !req
509. When we started filming,
everything was pretty much fine.
Copy !req
510. All of the corals
were basically healthy.
Copy !req
511. But in the last few weeks,
everything changed.
Copy !req
512. I have never seen anything
like this before.
Copy !req
513. A combination of a warming ocean
Copy !req
514. and an unpredictable weather event
called El Niño
Copy !req
515. raised sea temperatures
to record levels.
Copy !req
516. And this had a disastrous effect
on the corals.
Copy !req
517. The heat causes reef-building corals
to lose their nourishing algae,
Copy !req
518. exposing their white skeletons.
Copy !req
519. When temperatures remain high,
bleached corals die off.
Copy !req
520. The bleaching this year has been
the worst in history
Copy !req
521. for the Great Barrier Reef.
Copy !req
522. About 90 percent of the branching corals
Copy !req
523. on the reef out here at Lizard Island
are dead.
Copy !req
524. It also has disastrous consequences
Copy !req
525. for the other creatures that live here.
Copy !req
526. Percy swimming around out there.
Copy !req
527. The really sad thing is that his
castle's starting to bleach.
Copy !req
528. If we lose our coral, there's a chance
we're going to lose our tuskfish.
Copy !req
529. It's incredibly sad to see areas
that you've dived on
Copy !req
530. since you were a little kid
just turn to rubble.
Copy !req
531. I cried in my mask, when I saw,
Copy !req
532. you know, some of the devastation
from this bleaching.
Copy !req
533. In the last three years,
Copy !req
534. over two-thirds
of the world's coral reefs
Copy !req
535. are thought to have suffered from rises
in ocean temperatures.
Copy !req
536. This is not the only challenge
they face.
Copy !req
537. Research is revealing
how the fundamental
Copy !req
538. Chemistry of the ocean is changing.
Copy !req
539. Professor Chris Langdon shows me
what this might mean
Copy !req
540. for the future of our seas
by pouring dilute acid over shells.
Copy !req
541. And how much more acidic is this
than the present ocean?
Copy !req
542. This is more concentrated than
the pH of the ocean
Copy !req
543. but it accelerates the process
so we can see something visually.
Copy !req
544. So, what's happening is, these shells,
they're made out of calcium carbonate,
Copy !req
545. and the acid is dissolving them.
Copy !req
546. And coral reefs are made out of
the same material as these shells here.
Copy !req
547. But surely this is not happening
in the ocean now. Right now?
Copy !req
548. What we're seeing here is more dramatic
than what's happening in the ocean.
Copy !req
549. But the shells and the reefs
are really truly dissolving.
Copy !req
550. Coral reefs could be gone by the end
of this century.
Copy !req
551. And the cause of this? Carbon dioxide.
Copy !req
552. Dissolved in the sea water,
it forms carbonic acid.
Copy !req
553. The more carbon dioxide
in the atmosphere,
Copy !req
554. the more acidic the ocean becomes.
Copy !req
555. Evidence points to the burning
of fossil fuels
Copy !req
556. as the primary cause for these
increasing levels of carbon dioxide.
Copy !req
557. And this is man-made beyond question.
Copy !req
558. Beyond question.
Copy !req
559. But Chris believes all is not lost.
Copy !req
560. All we have to do, and I say all,
is reduce our C02 emissions.
Copy !req
561. We can switch to renewable fuels,
wind and solar,
Copy !req
562. instead of natural fossil fuels.
Copy !req
563. And so, none of this has to
Copy !req
564. - develop to the worst case.
- And that could fix it?
Copy !req
565. Yeah, absolutely. So, this future does
not have to play out. It's up to us.
Copy !req
566. As the climate changes, the seas warm.
Copy !req
567. Our oceans are being seriously affected.
Copy !req
568. And this is nowhere more apparent
than at the poles.
Copy !req
569. Antarctica.
Copy !req
570. For the Blue Planet II team, this was
their most ambitious expedition.
Copy !req
571. For the first time in history,
a manned submersible
Copy !req
572. will try to dive to a depth
of 1,000 metres
Copy !req
573. and reach the Antarctic seabed.
Copy !req
574. A true journey into the unknown.
Copy !req
575. Control rover. Passing 40 metres. Over.
Copy !req
576. Leading the team on this historic dive
Copy !req
577. is deep sea scientist John Copley.
Copy !req
578. We get our first glimpse
of this landscape.
Copy !req
579. And the carpet of life around us
is astounding.
Copy !req
580. It's beautiful.
Copy !req
581. Diving in a submersible
gives John an entirely new understanding
Copy !req
582. of how this rich ecosystem works.
Copy !req
583. But it also offers him
a unique opportunity
Copy !req
584. to investigate how the ocean here
is changing.
Copy !req
585. While we're observing the marine life
down there,
Copy !req
586. the subs are also recording
what the environment is like,
Copy !req
587. so we're getting measurements
of temperature, of salinity.
Copy !req
588. It's hopefully gonna enable us
to understand the changes
Copy !req
589. that are happening in this vital part
of our planet.
Copy !req
590. To get a fuller picture,
John also lowers
Copy !req
591. a deep sea temperature probe.
Copy !req
592. His data is contributing
to an international attempt
Copy !req
593. to chart the rise in both sea
and air temperatures.
Copy !req
594. What shocks me about
what all the data show
Copy !req
595. is how fast things are changing here.
Copy !req
596. We're headed into uncharted territory.
Copy !req
597. To truly comprehend
Copy !req
598. the effect of the temperature
increases here,
Copy !req
599. John takes to the skies.
Copy !req
600. From here, he can record
the number and size
Copy !req
601. of the icebergs being produced
as the ice shelfs melt and break apart.
Copy !req
602. The bergs we're seeing all around us
give you some idea
Copy !req
603. of how huge this process is
that's taking place on the Antarctic.
Copy !req
604. As the floating shelves
break up, they allow water,
Copy !req
605. which has been locked up on land as ice
for thousands of years,
Copy !req
606. to empty into the sea.
Copy !req
607. And this is predicted to push up
sea levels.
Copy !req
608. If the ice shelves break up,
then that opens the flood gates.
Copy !req
609. Ice on land flows faster into the sea
Copy !req
610. and that's what pushes up
the sea levels.
Copy !req
611. So, what's happening here right now
affects all of us.
Copy !req
612. Already, cities like Miami here
are under threat.
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613. Scientists predict that by the end
of the century,
Copy !req
614. the sea levels could have risen
by a metre or even two.
Copy !req
615. Were that to happen, parts of this city
would certainly be submerged.
Copy !req
616. Around the world, hundreds of millions
of people live near the coast,
Copy !req
617. and as sea levels rise,
their lives will be seriously affected.
Copy !req
618. It's now clear that our actions
are having a significant impact
Copy !req
619. on the world's oceans.
Copy !req
620. During the four years it took
to make this series,
Copy !req
621. we've witnessed many of these changes
first-hand.
Copy !req
622. But we've also worked alongside
men and women
Copy !req
623. dedicating their lives to safeguarding
the ocean's future.
Copy !req
624. The oceans provide us with oxygen,
Copy !req
625. they regulate temperature,
Copy !req
626. they provide us with food
and energy supplies.
Copy !req
627. And it's unthinkable to have a world
without a healthy ocean.
Copy !req
628. I still think we have the capability
Copy !req
629. to change the manner in which
we're wasting resources,
Copy !req
630. in which we're poisoning our oceans,
Copy !req
631. and we can look to a future
with healthy oceans.
Copy !req
632. When I look forward, I believe
that if what we are doing
Copy !req
633. can be duplicated just a little bit.
Copy !req
634. These animals will have a chance
of surviving.
Copy !req
635. It comes down, I think, to us each
taking responsibility
Copy !req
636. for the personal choices that we make
in our everyday lives.
Copy !req
637. That's all any of us can be expected
to do.
Copy !req
638. And it is those everyday choices
that add up.
Copy !req
639. We are at a unique stage in our history.
Copy !req
640. Never before have we had
such an awareness
Copy !req
641. of what we are doing to the planet.
Copy !req
642. And never before have we had the power
to do something about that.
Copy !req
643. Surely, we have a responsibility
to care for our blue planet.
Copy !req
644. The future of humanity,
Copy !req
645. and indeed all life on Earth,
Copy !req
646. now depends on us.
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