1 00:00:00,000 --> 00:00:02,480 Almost 200 years ago, 2 00:00:02,600 --> 00:00:06,320 Whilst walking these very paths in the English countryside 3 00:00:06,440 --> 00:00:09,800 and observing the banks and meadows near his home, 4 00:00:09,920 --> 00:00:12,560 Charles Darwin developed his ground-breaking ideas 5 00:00:12,680 --> 00:00:13,880 about evolution, 6 00:00:14,000 --> 00:00:16,800 casting a new light on the natural world 7 00:00:16,920 --> 00:00:20,120 and opening our eyes to its true wonder. 8 00:00:20,240 --> 00:00:25,120 Since then, we've explored almost every part of the planet 9 00:00:25,240 --> 00:00:28,880 and seen nature in its astounding variety. 10 00:00:29,000 --> 00:00:31,840 But there's still much to discover. 11 00:00:34,680 --> 00:00:38,520 In this new series of Planet Earth, 12 00:00:38,640 --> 00:00:42,360 we travel to the most astonishing Wild places... 13 00:00:45,000 --> 00:00:46,800 ...see mysterious creatures... 14 00:00:52,520 --> 00:00:55,480 ...witness spectacular wonders... 15 00:00:57,240 --> 00:01:00,400 ...and reveal breathtaking animal dramas. 16 00:01:05,680 --> 00:01:07,560 (SNARLS) 17 00:01:15,880 --> 00:01:19,720 The natural world continues to surprise us. 18 00:01:23,640 --> 00:01:28,880 But since Darwin's time, it has changed beyond recognition... 19 00:01:30,240 --> 00:01:34,960 ...transformed by a powerful force - us. 20 00:01:37,520 --> 00:01:42,240 We will see how animals are adapting in extraordinary ways 21 00:01:42,360 --> 00:01:45,320 to survive the new challenges they face. 22 00:01:48,360 --> 00:01:50,560 At this crucial time in our history, 23 00:01:50,680 --> 00:01:52,720 we must now look at the world 24 00:01:52,840 --> 00:01:55,240 through a new lens. 25 00:01:55,360 --> 00:01:58,480 This is Planet Earth III. 26 00:02:40,800 --> 00:02:42,680 Tasmania, 27 00:02:42,800 --> 00:02:44,880 Shipstern's Bluff, 28 00:02:45,000 --> 00:02:48,560 Where two worlds collide. 29 00:03:11,240 --> 00:03:12,760 These waves have crossed 30 00:03:12,880 --> 00:03:15,680 more than a thousand miles of open ocean... 31 00:03:18,600 --> 00:03:21,080 ...building in strength. 32 00:03:34,920 --> 00:03:38,560 It's here that they meet their explosive end. 33 00:04:05,160 --> 00:04:10,120 Coasts are dangerous and dynamic frontiers. 34 00:04:10,240 --> 00:04:14,800 To succeed here, life must adapt to constant change. 35 00:04:21,480 --> 00:04:24,000 South Africa's Robberg Peninsula. 36 00:04:28,080 --> 00:04:31,760 Thousands of Cape fur seals gather here to breed. 37 00:04:34,160 --> 00:04:37,320 (SEALS BARKING) 38 00:04:44,840 --> 00:04:49,000 This pup was born into a crowded world. 39 00:04:52,840 --> 00:04:55,400 But now, at nearly a year old, 40 00:04:55,520 --> 00:04:58,360 he can escape to the water. 41 00:05:05,760 --> 00:05:07,520 He just has to get there. 42 00:05:14,000 --> 00:05:15,000 (SNARLS) 43 00:05:15,120 --> 00:05:16,760 (GRUNTS) 44 00:05:38,560 --> 00:05:44,000 There is no question as to Where this pup belongs. 45 00:05:51,920 --> 00:05:56,640 In the water, he's fast and agile... 46 00:06:08,760 --> 00:06:11,160 ...and he needs to be. 47 00:06:14,600 --> 00:06:19,400 The rolling surf conceals life-threatening dangers. 48 00:06:45,760 --> 00:06:47,960 (SEAL YELPS) 49 00:06:51,360 --> 00:06:53,960 A great white shark. 50 00:07:11,360 --> 00:07:15,840 This young pup has had a very lucky escape. 51 00:07:32,040 --> 00:07:33,840 (SEALS BARKING) 52 00:07:33,960 --> 00:07:36,200 Here on Africa's southern coast, 53 00:07:36,320 --> 00:07:39,080 seals risk their lives every time 54 00:07:39,200 --> 00:07:41,720 they set out to eat. 55 00:07:46,440 --> 00:07:51,640 Powerful ocean currents attract huge shoals of fish. 56 00:08:00,320 --> 00:08:02,640 But in recent years, 57 00:08:02,760 --> 00:08:05,480 this stretch has attracted increased numbers 58 00:08:05,600 --> 00:08:07,760 of great Whites, too. 59 00:08:10,720 --> 00:08:13,280 The great whites are shrewd hunters 60 00:08:13,400 --> 00:08:16,040 and use Whatever cover is available. 61 00:08:35,200 --> 00:08:38,280 (SEALS BARKING) 62 00:08:45,360 --> 00:08:49,440 This shark won't need to eat for another few days. 63 00:08:53,360 --> 00:08:55,320 But he's not alone. 64 00:08:59,040 --> 00:09:01,840 These usually solitary hunters 65 00:09:01,960 --> 00:09:04,720 are gathering in unprecedented numbers... 66 00:09:07,520 --> 00:09:09,320 ...a dozen at a time. 67 00:09:22,000 --> 00:09:23,800 The seals are nimble... 68 00:09:29,680 --> 00:09:31,760 ...but great whites are patient... 69 00:09:38,400 --> 00:09:40,680 ...and have explosive acceleration... 70 00:09:43,880 --> 00:09:47,920 ...hitting top speed with just five swipes of their tails. 71 00:09:59,520 --> 00:10:04,400 Cornered, the seals keep close to the jagged cliffs. 72 00:10:10,840 --> 00:10:12,920 They're trapped. 73 00:10:57,080 --> 00:11:00,280 But as the great whites move in for the kill... 74 00:11:02,080 --> 00:11:04,560 ...the seals do something astonishing. 75 00:11:09,280 --> 00:11:13,400 Together, they turn on their enemy. 76 00:11:26,240 --> 00:11:29,600 As more join, the mob grows... 77 00:11:31,280 --> 00:11:34,280 ...in both number and confidence. 78 00:11:47,160 --> 00:11:49,640 The tables are turning. 79 00:12:15,560 --> 00:12:17,880 By sheer force of numbers, 80 00:12:18,000 --> 00:12:20,040 these fur seals drive 81 00:12:20,160 --> 00:12:22,440 the world's most notorious predator... 82 00:12:24,680 --> 00:12:26,960 ...back out to sea. 83 00:12:34,240 --> 00:12:38,520 Here, animals are adapting to new challenges 84 00:12:38,640 --> 00:12:41,080 in a rapidly changing world. 85 00:12:49,560 --> 00:12:51,720 In the Arctic, 86 00:12:51,840 --> 00:12:55,760 monumental change is a regular event. 87 00:13:01,200 --> 00:13:03,360 (BLOWS) 88 00:13:03,480 --> 00:13:07,560 Summer. Visitors are arriving en masse... 89 00:13:08,840 --> 00:13:12,680 ...attracted by the biggest seasonal transformation 90 00:13:12,800 --> 00:13:14,480 on any coast on Earth. 91 00:13:25,520 --> 00:13:30,360 Over 300 billion tons of ice are melting... 92 00:13:34,960 --> 00:13:38,080 ...releasing nutrient-rich water. 93 00:13:42,360 --> 00:13:45,560 Extraordinary newcomers appear from the depths. 94 00:13:57,080 --> 00:13:58,600 A sea angel... 95 00:14:01,400 --> 00:14:04,080 ...no bigger than your little finger. 96 00:14:13,400 --> 00:14:15,920 It's eaten little for months. 97 00:14:16,040 --> 00:14:19,280 Its empty stomach glows orange. 98 00:14:29,760 --> 00:14:32,560 And there are other hungry arrivals. 99 00:14:37,600 --> 00:14:39,280 A sea butterfly... 100 00:14:41,280 --> 00:14:43,440 ...a snail with Wings. 101 00:14:52,320 --> 00:14:56,240 Both angel and butterfly are blind... 102 00:14:57,960 --> 00:15:01,400 ...but each monitors minute changes in the water 103 00:15:01,520 --> 00:15:03,600 as they search for a meal. 104 00:15:18,760 --> 00:15:21,800 This angel has a devilish side. 105 00:15:24,720 --> 00:15:28,080 Its mouthparts invert... 106 00:15:28,200 --> 00:15:31,080 ...to form a deadly trap of tentacles... 107 00:15:41,960 --> 00:15:45,200 ...from which there is little chance of escape. 108 00:16:23,560 --> 00:16:25,720 With a stomach full of prey, 109 00:16:25,840 --> 00:16:28,440 this angel has lost its glow... 110 00:16:30,440 --> 00:16:32,360 ...but not its appetite. 111 00:16:37,440 --> 00:16:40,200 It feasts While it can. 112 00:16:46,600 --> 00:16:48,480 Both predator and prey 113 00:16:48,600 --> 00:16:50,960 will soon return to the depths... 114 00:16:52,200 --> 00:16:56,160 ...before the ice transforms this coast once again. 115 00:17:00,080 --> 00:17:02,000 (WIND GUSTS) 116 00:17:14,320 --> 00:17:16,520 Namibia, 117 00:17:16,640 --> 00:17:20,960 Where desert lions roam across vast territories. 118 00:17:21,080 --> 00:17:23,520 (LION GROWLS) 119 00:17:29,840 --> 00:17:34,640 These desert cats are on a never-ending search for food. 120 00:17:41,040 --> 00:17:43,720 And that has brought these young sisters... 121 00:17:45,120 --> 00:17:46,560 ...here... 122 00:17:56,400 --> 00:18:00,120 ...Africa's infamous Skeleton Coast. 123 00:18:05,840 --> 00:18:07,880 Following years of persecution, 124 00:18:08,000 --> 00:18:11,040 Namibia's lions are now protected, 125 00:18:11,160 --> 00:18:12,600 and their range 126 00:18:12,720 --> 00:18:14,400 is expanding again. 127 00:18:16,440 --> 00:18:18,400 These are the first to be seen 128 00:18:18,520 --> 00:18:20,880 on these shores for 40 years. 129 00:18:25,600 --> 00:18:29,280 By day, there is little for them here. 130 00:18:29,400 --> 00:18:32,120 (GROW LS SOFTLY) 131 00:18:32,240 --> 00:18:35,240 But at night, it's a different story. 132 00:18:39,520 --> 00:18:42,440 (BIRDS CALL) 133 00:18:45,360 --> 00:18:49,880 Sea birds come here to roost in their thousands. 134 00:19:00,680 --> 00:19:05,120 These hungry sisters have never seen an opportunity like this. 135 00:19:09,480 --> 00:19:12,960 But no cats, certainly no desert cats, 136 00:19:13,080 --> 00:19:15,960 enjoy getting their paws wet. 137 00:19:28,520 --> 00:19:33,680 These roosting cormorants are sitting ducks 138 00:19:33,800 --> 00:19:36,400 for hunters with good night vision... 139 00:19:40,360 --> 00:19:43,560 (BIRDS SQUAWK) 140 00:19:46,840 --> 00:19:48,160 ...in theory. 141 00:19:58,200 --> 00:20:01,080 Birds are not a big cat's usual prey, 142 00:20:01,200 --> 00:20:03,240 let alone sea birds... 143 00:20:05,120 --> 00:20:08,320 ...and these sisters need to get their eye in. 144 00:20:37,720 --> 00:20:39,440 (CHICK CHIRPS) 145 00:20:41,200 --> 00:20:45,040 Catching flying prey in the dark is not easy... 146 00:20:46,120 --> 00:20:49,280 ...but these lions have acquired the knack. 147 00:20:53,600 --> 00:20:56,280 Coasts can not only provide food... 148 00:21:09,120 --> 00:21:12,120 ...they can also be a sanctuary. 149 00:21:15,760 --> 00:21:18,400 (WHALE GRUNTS) 150 00:21:22,880 --> 00:21:24,760 (CLICKING) 151 00:21:24,880 --> 00:21:28,560 This female southern right whale is nearing the end 152 00:21:28,680 --> 00:21:32,960 of a 5,000-mile journey across open ocean. 153 00:21:45,880 --> 00:21:48,200 She's kept a steady course... 154 00:21:50,120 --> 00:21:53,640 ...to a special place she has known all her life... 155 00:21:58,560 --> 00:22:02,000 ...Peninsula Valdés, Argentina. 156 00:22:24,520 --> 00:22:27,800 In these calm, shallow waters, 157 00:22:27,920 --> 00:22:30,920 her behaviour starts to change. 158 00:22:33,200 --> 00:22:36,640 She rolls and shifts her great body. 159 00:22:41,560 --> 00:22:44,200 Perhaps she's trying to get comfortable. 160 00:22:44,320 --> 00:22:46,320 (GRUNTS) 161 00:22:52,520 --> 00:22:54,840 (GRUNTS) 162 00:23:07,200 --> 00:23:09,360 (GRUNTS) 163 00:23:12,680 --> 00:23:14,800 Other females are close by. 164 00:23:18,480 --> 00:23:21,720 Some have been coming here for five decades... 165 00:23:23,040 --> 00:23:25,240 ...seeking the shelter of this bay 166 00:23:25,360 --> 00:23:27,520 at a key time in their lives. 167 00:23:30,240 --> 00:23:32,720 (GRUNTING) 168 00:23:44,440 --> 00:23:47,800 This whale is here 169 00:23:47,920 --> 00:23:50,160 to give birth. 170 00:24:16,880 --> 00:24:18,600 (BLOWS) 171 00:24:20,080 --> 00:24:22,960 A new life begins. 172 00:24:34,840 --> 00:24:38,160 The calf is totally dependent on its mother. 173 00:24:40,880 --> 00:24:45,600 She's producing as much as 200 litres of milk a day. 174 00:24:47,960 --> 00:24:49,840 The strength she loses, 175 00:24:49,960 --> 00:24:52,360 the calf gains... 176 00:24:58,320 --> 00:25:03,600 ...and it becomes more and more independent and playful. 177 00:25:13,400 --> 00:25:15,080 In this nursery bay, 178 00:25:15,200 --> 00:25:17,920 there are plenty of playmates. 179 00:25:28,040 --> 00:25:31,800 But a mother never lets her calf stray too far... 180 00:25:39,280 --> 00:25:43,520 ...and will always offer a welcome embrace. 181 00:25:52,240 --> 00:25:56,360 (CALLS GENTLY) 182 00:25:56,480 --> 00:26:01,840 The family keeps in constant contact with Whispered calls. 183 00:26:03,280 --> 00:26:07,120 New research has revealed that in shallow coastal waters 184 00:26:07,240 --> 00:26:10,840 their calls not only fade quickly, 185 00:26:10,960 --> 00:26:12,520 but are also concealed 186 00:26:12,640 --> 00:26:15,800 by the sound of waves breaking on the shore... 187 00:26:15,920 --> 00:26:17,600 (WAVES LAP) 188 00:26:17,720 --> 00:26:19,560 (WHALE CALLS GENTLY) 189 00:26:21,760 --> 00:26:25,680 ...so they won't attract the attention of predators. 190 00:26:30,640 --> 00:26:34,920 Not so long ago, these whales faced a graver threat. 191 00:26:38,040 --> 00:26:40,840 They were hunted to near extinction. 192 00:26:43,880 --> 00:26:45,440 But 40 years ago, 193 00:26:45,560 --> 00:26:48,560 commercial Whaling was banned. 194 00:26:51,800 --> 00:26:56,800 Today, their population is 12,000 strong, 195 00:26:56,920 --> 00:27:00,440 and this bay now attracts one of the largest gatherings 196 00:27:00,560 --> 00:27:03,760 of these whales anywhere on Earth. 197 00:27:25,200 --> 00:27:29,720 There are over a million miles of coastline around the world. 198 00:27:31,280 --> 00:27:33,080 Together, they constitute 199 00:27:33,200 --> 00:27:36,320 the most varied habitat on the planet. 200 00:27:40,000 --> 00:27:42,640 Here, on Canada's west coast, 201 00:27:42,760 --> 00:27:46,160 some of the most powerful of all ocean currents 202 00:27:46,280 --> 00:27:49,160 deliver a constant supply of nutrients 203 00:27:49,280 --> 00:27:51,960 to the shores of countless islands. 204 00:27:54,920 --> 00:27:56,720 (BIRDSONG) 205 00:28:06,000 --> 00:28:07,920 And those that live here 206 00:28:08,040 --> 00:28:10,280 take full advantage. 207 00:28:16,560 --> 00:28:21,840 This is the aptly named wandering garter snake. 208 00:28:26,680 --> 00:28:29,440 (HISSES) 209 00:28:31,720 --> 00:28:33,000 (HISSES) 210 00:28:39,800 --> 00:28:41,640 He may seem out of place, 211 00:28:41,760 --> 00:28:44,440 but he's here to eat. 212 00:28:56,360 --> 00:28:59,880 The water here is more than ten degrees colder 213 00:29:00,000 --> 00:29:01,360 than the air. 214 00:29:07,400 --> 00:29:11,360 But that doesn't deter this intrepid hunter 215 00:29:11,480 --> 00:29:13,320 from taking the plunge. 216 00:29:18,840 --> 00:29:22,560 Under the water, there is an abundance of food... 217 00:29:24,600 --> 00:29:26,200 ...if you can catch it. 218 00:29:53,640 --> 00:29:55,360 Snakes are cold-blooded, 219 00:29:55,480 --> 00:29:59,000 so he can't stay in these chilly waters for long. 220 00:30:06,360 --> 00:30:09,520 Back in the sunshine, he warms his head, 221 00:30:09,640 --> 00:30:12,560 perhaps sharpening his senses. 222 00:30:15,520 --> 00:30:17,680 And then, with a gulp of air... 223 00:30:19,440 --> 00:30:21,240 ...he continues his hunt. 224 00:30:28,640 --> 00:30:30,400 It's thought that garter snakes 225 00:30:30,520 --> 00:30:33,200 can use their forked tongue underwater, 226 00:30:33,320 --> 00:30:38,240 as they do in air, smelling in stereo, 227 00:30:38,360 --> 00:30:41,400 detecting prey wherever it hides. 228 00:30:57,320 --> 00:30:58,720 He's got something. 229 00:31:00,080 --> 00:31:01,520 A small fish. 230 00:31:06,960 --> 00:31:09,360 Now he has to land it. 231 00:31:13,320 --> 00:31:14,760 Success. 232 00:31:19,680 --> 00:31:22,400 For those animals able to cross the divide 233 00:31:22,520 --> 00:31:26,880 between land and sea, there are surprising rewards. 234 00:31:33,400 --> 00:31:36,360 Raja Ampat in Indonesia. 235 00:31:40,080 --> 00:31:43,280 Here, there's a greater variety of animals 236 00:31:43,400 --> 00:31:45,840 than on any other coast on Earth. 237 00:31:51,960 --> 00:31:55,040 The corals are protected by mangroves, 238 00:31:55,160 --> 00:31:57,760 salt-tolerant trees 239 00:31:57,880 --> 00:32:01,680 that prop themselves on curving aerial roots. 240 00:32:14,640 --> 00:32:17,520 These fish have learned how to catch prey 241 00:32:17,640 --> 00:32:19,960 from high in the trees. 242 00:32:26,000 --> 00:32:29,920 Archerfish use jets of water like arrows. 243 00:32:34,720 --> 00:32:37,280 This pinpoint accuracy 244 00:32:37,400 --> 00:32:40,240 requires some complex calculations. 245 00:32:42,200 --> 00:32:45,840 The hunter first estimates the range of its target... 246 00:32:48,920 --> 00:32:52,560 ...then loads with a precise amount of water. 247 00:32:52,680 --> 00:32:53,760 (GULPS) 248 00:32:54,840 --> 00:32:59,080 Aiming, they allow for the refraction and distortion 249 00:32:59,200 --> 00:33:01,960 created by the water's moving surface. 250 00:33:05,800 --> 00:33:07,800 And then... 251 00:33:07,920 --> 00:33:09,840 ...release... 252 00:33:12,360 --> 00:33:14,120 ...an arrow of water. 253 00:33:16,520 --> 00:33:18,920 They can hit prey 254 00:33:19,040 --> 00:33:21,880 up to two metres above them. 255 00:33:30,760 --> 00:33:34,000 But they're not born with this skill. 256 00:33:35,920 --> 00:33:37,440 They have to learn it. 257 00:33:39,560 --> 00:33:42,800 And they do that by studying others. 258 00:33:47,760 --> 00:33:52,840 This youngster is watching a master at work. 259 00:34:08,760 --> 00:34:11,760 It's time for the apprentice to have a go. 260 00:34:14,480 --> 00:34:17,440 First, he must select a target. 261 00:34:20,760 --> 00:34:22,800 This seems rather ambitious. 262 00:34:31,720 --> 00:34:33,200 Missed. 263 00:34:34,480 --> 00:34:37,400 Others watch to learn from his mistakes... 264 00:34:47,480 --> 00:34:48,840 ...OI'... 265 00:34:51,120 --> 00:34:52,960 ...to steal his prize. 266 00:35:30,040 --> 00:35:32,320 Enough is enough. 267 00:35:34,400 --> 00:35:36,800 There is one way to beat the thieves. 268 00:35:41,880 --> 00:35:44,600 The archer himself 269 00:35:44,720 --> 00:35:46,760 becomes the arrow. 270 00:36:08,360 --> 00:36:12,360 Mangroves are unusually stable coastal environments, 271 00:36:12,480 --> 00:36:16,800 Where an archerfish can focus on beating the competition. 272 00:36:36,360 --> 00:36:40,440 But on the exposed coast of Mexico's Yucatan, 273 00:36:40,560 --> 00:36:42,520 life is precarious. 274 00:36:45,000 --> 00:36:48,040 Concentrated by the tropical sunshine, 275 00:36:48,160 --> 00:36:50,720 the brine in these shallow lagoons 276 00:36:50,840 --> 00:36:53,800 cannot be tolerated by most animals. 277 00:36:57,960 --> 00:37:01,480 And yet these Caribbean flamingos 278 00:37:01,600 --> 00:37:04,840 have flown hundreds of miles to gather here. 279 00:37:28,440 --> 00:37:31,200 (FLAMINGOS SQUAWK) 280 00:37:41,200 --> 00:37:45,720 These hypersaline waters keep many predators at bay... 281 00:37:48,680 --> 00:37:51,440 ...so it's here they choose to nest. 282 00:37:54,400 --> 00:37:57,240 There are more than 10,000 pairs here. 283 00:37:57,360 --> 00:38:00,840 It's the largest breeding colony in North America. 284 00:38:00,960 --> 00:38:02,680 (FLAMINGOS SQUAWKING) 285 00:38:14,880 --> 00:38:18,200 Nest mounds keep chicks clear of the brine 286 00:38:18,320 --> 00:38:21,080 While they're still at their most vulnerable. 287 00:38:23,360 --> 00:38:24,640 (CHIRPS) 288 00:38:31,160 --> 00:38:32,560 (CHIRPS) 289 00:38:41,960 --> 00:38:43,600 (CHIRPS) 290 00:38:43,720 --> 00:38:45,240 (CHIRPING) 291 00:38:57,400 --> 00:39:00,440 But this generation faces a problem. 292 00:39:00,560 --> 00:39:01,720 (CHIRPS) 293 00:39:01,840 --> 00:39:04,920 (THUNDER RUMBLES) 294 00:39:08,600 --> 00:39:10,680 The storms that come each season 295 00:39:10,800 --> 00:39:13,640 are arriving earlier every year... 296 00:39:17,320 --> 00:39:21,240 ...and the colony lies directly in their path. 297 00:39:22,280 --> 00:39:24,880 (WIND GUSTS) 298 00:39:31,400 --> 00:39:35,240 Rising winds create a storm surge 299 00:39:35,360 --> 00:39:38,760 that overwhelms the most exposed nests. 300 00:39:40,160 --> 00:39:42,280 (SQUAWKING) 301 00:39:53,360 --> 00:39:56,080 (THUNDER RUMBLES) 302 00:40:02,120 --> 00:40:05,560 And then...it rains. 303 00:40:14,160 --> 00:40:18,240 The adults do what they can, bailing out their nests. 304 00:40:25,200 --> 00:40:27,840 But they can only do so much. 305 00:40:44,400 --> 00:40:49,640 The storm passes...but leaves devastation in its wake. 306 00:40:54,200 --> 00:40:56,480 Most nests are submerged. 307 00:41:07,600 --> 00:41:09,840 (CHIRPS) 308 00:41:13,080 --> 00:41:15,720 The chicks are soaked and cold... 309 00:41:17,440 --> 00:41:20,240 ...and will soon perish 310 00:41:20,360 --> 00:41:23,000 unless they can get out of the water. 311 00:41:29,360 --> 00:41:31,360 (CHIRPING) 312 00:41:36,760 --> 00:41:39,560 The adults are unable to help. 313 00:41:44,040 --> 00:41:46,680 A chick must save itself. 314 00:41:55,280 --> 00:41:57,360 (WATER SPLASHES) 315 00:41:57,480 --> 00:41:59,160 (CHIRPING) 316 00:42:13,160 --> 00:42:14,480 Some years, 317 00:42:14,600 --> 00:42:17,720 no chicks survive in this colony. 318 00:42:21,560 --> 00:42:25,720 Our coasts are vulnerable places, 319 00:42:25,840 --> 00:42:29,400 increasingly so as rising global temperatures 320 00:42:29,520 --> 00:42:31,560 create bigger storms. 321 00:42:34,120 --> 00:42:35,720 (RUMBLING) 322 00:42:35,840 --> 00:42:39,120 The biggest are hurricanes. 323 00:42:42,480 --> 00:42:45,520 They form over warm tropical water, 324 00:42:45,640 --> 00:42:48,040 building in strength at sea. 325 00:42:51,320 --> 00:42:55,200 But their full force is unleashed on our coasts... 326 00:42:58,120 --> 00:43:01,800 ...Where 40% of the world's human population 327 00:43:01,920 --> 00:43:03,480 have made their homes. 328 00:43:16,720 --> 00:43:18,680 In this changing world... 329 00:43:20,440 --> 00:43:22,920 ...coasts are on the front line. 330 00:43:39,400 --> 00:43:41,920 Raine Island, 331 00:43:42,040 --> 00:43:45,080 one of the planet's most important breeding sites 332 00:43:45,200 --> 00:43:48,360 for one particularly precious species. 333 00:44:02,400 --> 00:44:04,320 The green turtle. 334 00:44:08,480 --> 00:44:11,240 On a few special nights each year, 335 00:44:11,360 --> 00:44:15,200 as many as 20,000 females come ashore here. 336 00:44:17,960 --> 00:44:20,320 Their instinct to nest is strong... 337 00:44:22,720 --> 00:44:26,720 ...and many haul themselves far inland 338 00:44:26,840 --> 00:44:28,400 in search of nesting space. 339 00:44:31,160 --> 00:44:32,880 In a single night, 340 00:44:33,000 --> 00:44:36,360 they may lay as many as two million eggs. 341 00:44:37,960 --> 00:44:39,880 (HUFFS) 342 00:44:45,360 --> 00:44:48,680 (BIRDS SQUAWK) 343 00:44:49,800 --> 00:44:51,040 Dawn. 344 00:44:53,920 --> 00:44:57,160 This exhausted female has nested, 345 00:44:57,280 --> 00:45:00,280 but now she faces a long return journey 346 00:45:00,400 --> 00:45:02,800 through the dunes to the sea. 347 00:45:02,920 --> 00:45:04,520 (HUFFS) 348 00:45:10,920 --> 00:45:12,880 (HUFFS) 349 00:45:15,960 --> 00:45:17,600 As the sun rises... 350 00:45:19,880 --> 00:45:23,200 ...she is at risk of being baked alive. 351 00:45:31,280 --> 00:45:35,160 Every inch she travels is gruelling. 352 00:45:43,440 --> 00:45:47,400 And the ebbing tide has exposed a rocky reef. 353 00:45:52,960 --> 00:45:55,760 It has already claimed many lives... 354 00:46:00,280 --> 00:46:04,600 ...other females overcome by heat and exhaustion. 355 00:46:14,840 --> 00:46:16,960 Her temperature is rising. 356 00:46:17,080 --> 00:46:19,280 She has to keep going. 357 00:46:36,400 --> 00:46:38,160 (GRUNTS) 358 00:46:44,440 --> 00:46:48,040 As many as 2,000 female turtles 359 00:46:48,160 --> 00:46:50,680 may die here each year. 360 00:46:52,440 --> 00:46:55,080 (GRUNTING) 361 00:47:12,120 --> 00:47:15,160 But the coast is always changing. 362 00:47:24,440 --> 00:47:28,920 And the turning tide may yet save her. 363 00:47:57,880 --> 00:48:01,000 Half of all the green turtles in the Pacific 364 00:48:01,120 --> 00:48:02,880 come here to nest, 365 00:48:03,000 --> 00:48:06,640 as they have done for at least 1,000 years. 366 00:48:15,360 --> 00:48:17,720 But for how much longer? 367 00:48:23,560 --> 00:48:26,120 If sea levels rise as predicted, 368 00:48:26,240 --> 00:48:28,640 Within the next 30 years 369 00:48:28,760 --> 00:48:33,400 Raine Island will disappear beneath the waves. 370 00:48:41,040 --> 00:48:44,520 Coasts are dynamic, dangerous frontiers. 371 00:48:46,840 --> 00:48:49,640 And they are changing faster than ever before 372 00:48:49,760 --> 00:48:51,120 in human history. 373 00:48:54,920 --> 00:48:58,720 Life is remarkably resilient 374 00:48:58,840 --> 00:49:01,440 and adapts to new challenges. 375 00:49:04,080 --> 00:49:06,480 But there is a limit 376 00:49:06,600 --> 00:49:09,320 on how fast it can do so. 377 00:49:30,200 --> 00:49:33,680 As far as I know, I was one of the first people to film 378 00:49:33,800 --> 00:49:36,800 on Raine Island, back in 1957. 379 00:49:39,360 --> 00:49:41,440 YOUNG DAVID: After a fortnight of travelling north, 380 00:49:41,560 --> 00:49:45,040 we at last sighted Raine Island. 381 00:49:45,160 --> 00:49:47,520 From the sea, it looked no more 382 00:49:47,640 --> 00:49:50,080 than a low sandbank covered in scrub, 383 00:49:50,200 --> 00:49:52,800 but as we rowed ashore, 384 00:49:52,920 --> 00:49:57,400 we were deafened by the cries of thousands of sea birds 385 00:49:57,520 --> 00:49:59,920 which hung above the island like a black cloud. 386 00:50:03,200 --> 00:50:04,640 DAVID: [was 31, 387 00:50:04,760 --> 00:50:08,280 and it was here that I first met a green turtle. 388 00:50:09,640 --> 00:50:12,360 YOUNG DAVID: The turtles come up to lay at night, 389 00:50:12,480 --> 00:50:16,240 and after a night spent laying maybe over 100 eggs, 390 00:50:16,360 --> 00:50:18,080 she's very weary 391 00:50:18,200 --> 00:50:20,520 and very anxious to get back to the sea. 392 00:50:24,040 --> 00:50:27,160 DAVID: Nearly 70 years later, the Planet Earth III team 393 00:50:27,280 --> 00:50:29,240 are welcomed by people 394 00:50:29,360 --> 00:50:30,800 whose connection to the island 395 00:50:30,920 --> 00:50:32,920 goes back very much further than mine. 396 00:50:33,040 --> 00:50:34,960 Welcome to Raine! 397 00:50:35,080 --> 00:50:38,560 The Wuthathi and Meriam people have been coming here 398 00:50:38,680 --> 00:50:40,560 for several thousand years. 399 00:50:41,800 --> 00:50:44,200 Raine Island is a beautiful and special place. 400 00:50:44,320 --> 00:50:46,640 Like, there's nowhere else in the planet 401 00:50:46,760 --> 00:50:48,840 Where you come and see this much turtles. 402 00:50:48,960 --> 00:50:50,960 It's a wonder to see. 403 00:50:54,760 --> 00:50:56,440 Since I was there, 404 00:50:56,560 --> 00:50:58,560 it's been discovered that Raine Island attracts 405 00:50:58,680 --> 00:51:02,240 more nesting green turtles than anywhere else on the planet. 406 00:51:08,400 --> 00:51:11,560 So many! As soon as you're up, you're, "Oh, there are a lot." 407 00:51:12,560 --> 00:51:16,120 And the crew soon meet some other residents, too. 408 00:51:16,240 --> 00:51:19,520 This is behind the behind-the-scenes! 409 00:51:22,560 --> 00:51:23,760 Yeah! 410 00:51:23,880 --> 00:51:25,680 Aww. See you, mate. 411 00:51:29,160 --> 00:51:30,960 The team are here to record 412 00:51:31,080 --> 00:51:34,360 the mother turtles' perilous journeys back to the sea. 413 00:51:36,320 --> 00:51:37,840 CREW MEMBER: Oh, God. 414 00:51:40,080 --> 00:51:42,360 Trapped turtles can often free themselves 415 00:51:42,480 --> 00:51:44,800 with the help of the rising tide. 416 00:51:44,920 --> 00:51:48,000 Yeah, nearly. Just a bit more to the right. There... 417 00:51:48,120 --> 00:51:49,160 Yeah, there. 418 00:51:49,280 --> 00:51:53,600 But in this case, Keron makes the decision to intervene. 419 00:51:54,600 --> 00:51:56,800 Ready? One. two, three. 420 00:51:56,920 --> 00:51:58,920 KERON: Yeah, any time we're here, 421 00:51:59,040 --> 00:52:00,280 we'll walk the beach. 422 00:52:00,400 --> 00:52:03,680 Any turtles that have no chance of making it back to the ocean, 423 00:52:03,800 --> 00:52:06,240 if we can save 'em, we save 'em, 424 00:52:06,360 --> 00:52:09,000 because every turtle is precious. 425 00:52:09,120 --> 00:52:11,840 At the time of my first visit, little was known 426 00:52:11,960 --> 00:52:14,160 to outsiders about Raine Island. 427 00:52:14,280 --> 00:52:17,560 But for the last few decades, scientists have been working 428 00:52:17,680 --> 00:52:21,480 with the Wuthathi and Meriam people to understand 429 00:52:21,600 --> 00:52:24,000 more about this special place. 430 00:52:24,120 --> 00:52:26,320 WOMAN: Scientists have been coming to Raine Island 431 00:52:26,440 --> 00:52:27,440 since about the mid-'70s, 432 00:52:27,560 --> 00:52:30,360 and over that time they've been monitoring 433 00:52:30,480 --> 00:52:31,920 the nesting population here. 434 00:52:33,840 --> 00:52:36,200 This work involves long hours... 435 00:52:38,320 --> 00:52:39,960 98.7, yeah. 436 00:52:40,080 --> 00:52:42,160 ...and a certain degree of patience. 437 00:52:44,120 --> 00:52:45,640 MAN: AW! 438 00:52:45,760 --> 00:52:46,960 (KATHARINE LAUGHS) 439 00:52:47,080 --> 00:52:49,200 MAN: Urgh! 440 00:52:51,000 --> 00:52:53,120 KATHARINE: We're going to be wearing half of Raine Island 441 00:52:53,240 --> 00:52:55,080 by the end of tonight! 442 00:52:57,320 --> 00:52:59,400 Helping the year's first hatchlings 443 00:52:59,520 --> 00:53:01,800 is a little easier. 444 00:53:01,920 --> 00:53:03,880 So, we'll take these ones down to the water's edge, 445 00:53:04,000 --> 00:53:07,240 so hopefully we'll see these turtles back here laying eggs 446 00:53:07,360 --> 00:53:08,960 in 30 years' time. 447 00:53:09,080 --> 00:53:11,680 With the help of this dedicated team, 448 00:53:11,800 --> 00:53:13,240 Raine Island's turtles 449 00:53:13,360 --> 00:53:15,640 might seem to have a good future. 450 00:53:20,560 --> 00:53:23,600 But research is revealing a hidden threat. 451 00:53:28,160 --> 00:53:30,880 The direct effects of climate change. 452 00:53:35,120 --> 00:53:36,520 Do you want to hold this 453 00:53:36,640 --> 00:53:39,240 against the flat part of the data logger? 454 00:53:39,360 --> 00:53:40,720 A developing turtle's sex 455 00:53:40,840 --> 00:53:44,000 is determined by the temperature of its nest. 456 00:53:45,040 --> 00:53:48,880 Higher temperatures produce female hatchlings. 457 00:53:50,800 --> 00:53:53,840 The temperature of the sand on Raine Island is now 458 00:53:53,960 --> 00:53:56,000 at a record high, 459 00:53:56,120 --> 00:54:00,840 so 99% of the turtles that hatch here are female. 460 00:54:02,320 --> 00:54:03,720 More alarmingly, 461 00:54:03,840 --> 00:54:05,960 we now know this has been the case 462 00:54:06,080 --> 00:54:08,440 for at least the last 20 years. 463 00:54:09,640 --> 00:54:13,880 You do the math - all females, no males. 464 00:54:14,000 --> 00:54:15,280 What's gonna happen? 465 00:54:15,400 --> 00:54:17,480 There's going to be a population crash 466 00:54:17,600 --> 00:54:19,640 and there'll be no more turtles. 467 00:54:22,920 --> 00:54:25,840 Work is under way to find solutions, 468 00:54:25,960 --> 00:54:28,400 but that's not their only problem. 469 00:54:29,800 --> 00:54:32,920 Not only are temperatures rising, 470 00:54:33,040 --> 00:54:35,680 sea levels are, too. 471 00:54:35,800 --> 00:54:38,960 Increasingly, high tides on Raine are flooding 472 00:54:39,080 --> 00:54:41,640 many of the nests from below... 473 00:54:44,480 --> 00:54:47,720 ...drowning the developing turtles before they hatch. 474 00:54:48,960 --> 00:54:51,240 It's really upsetting. You'll dig down 475 00:54:51,360 --> 00:54:53,040 to check to see success, 476 00:54:53,160 --> 00:54:55,720 and you get down to the nest 477 00:54:55,840 --> 00:54:58,080 and you're just pulling up dead eggs. 478 00:54:59,720 --> 00:55:01,080 To try and stop this happening, 479 00:55:01,200 --> 00:55:04,520 they have devised a heavy-duty solution. 480 00:55:09,240 --> 00:55:12,040 These machines have been shipped hundreds of miles 481 00:55:12,160 --> 00:55:16,000 from the Australian mainland to reshape the beach. 482 00:55:18,840 --> 00:55:20,840 They have already shifted sand 483 00:55:20,960 --> 00:55:24,360 that would fill 16 Olympic-sized swimming pools 484 00:55:24,480 --> 00:55:27,080 and doubled the number of safe nesting sites. 485 00:55:29,640 --> 00:55:32,080 The hope is that this will ensure 486 00:55:32,200 --> 00:55:34,240 that over five million more eggs 487 00:55:34,360 --> 00:55:36,480 will hatch in the next decade. 488 00:55:39,760 --> 00:55:42,480 But from then on, the future of Raine Island 489 00:55:42,600 --> 00:55:45,160 looks very uncertain. 490 00:55:46,240 --> 00:55:48,600 KATHARINE: At this stage, we think that we have 491 00:55:48,720 --> 00:55:50,520 until about 2050 until we start seeing 492 00:55:50,640 --> 00:55:53,520 massive impacts of sea level rise. 493 00:55:53,640 --> 00:55:56,000 It's crazy to think that, you know, 494 00:55:56,120 --> 00:55:57,640 the work that we do here, 495 00:55:57,760 --> 00:55:59,560 someone might not be doing this in 30 years' time 496 00:55:59,680 --> 00:56:01,640 cos there's no island to do it on. 497 00:56:05,400 --> 00:56:08,880 KERON: What sort of world is it going to be for my children 498 00:56:09,000 --> 00:56:10,560 and their children? 499 00:56:10,680 --> 00:56:13,880 Is there going to be anything for... 500 00:56:14,000 --> 00:56:18,320 ...for them, or is it...all in vain? 501 00:56:23,680 --> 00:56:27,960 We'll always be here fighting for Raine Island, the turtles, 502 00:56:28,080 --> 00:56:29,160 but we can't do it alone. 503 00:56:29,280 --> 00:56:32,040 We need government and big business to wake up 504 00:56:32,160 --> 00:56:34,120 and see what they're doing to the planet 505 00:56:34,240 --> 00:56:35,920 and get real. 506 00:56:41,720 --> 00:56:44,600 YOUNG DAVID: This little fellow is newly hatched from an egg 507 00:56:44,720 --> 00:56:46,600 which had been laid a month or so earlier, 508 00:56:46,720 --> 00:56:50,240 and he, too, is very anxious to get down to the sea. 509 00:56:54,080 --> 00:56:56,640 Having at last successfully reached the water, 510 00:56:56,760 --> 00:56:59,400 he's still got a great number of hazards to face 511 00:56:59,520 --> 00:57:00,920 before he grows up. 512 00:57:02,080 --> 00:57:04,560 DAVID: Little did I know then 513 00:57:04,680 --> 00:57:07,720 what hazards that little turtle would have to face, 514 00:57:07,840 --> 00:57:11,200 or the extraordinary lengths to which people would go 515 00:57:11,320 --> 00:57:13,800 to protect it and its island. 516 00:57:15,080 --> 00:57:18,240 In the 66 years since my visit, 517 00:57:18,360 --> 00:57:20,360 Raine Island has remained 518 00:57:20,480 --> 00:57:24,720 the most important green turtle nesting site on the planet. 519 00:57:24,840 --> 00:57:28,760 The question is, can it last another lifetime?