1 00:00:09,960 --> 00:00:11,960 'The sun. 2 00:00:11,960 --> 00:00:17,640 '15 million degrees Celsius at its core. 3 00:00:17,640 --> 00:00:19,800 'Too close, 4 00:00:19,800 --> 00:00:20,960 'and you burn. 5 00:00:21,960 --> 00:00:23,960 'Too far... 6 00:00:24,960 --> 00:00:26,960 '..you freeze. 7 00:00:26,960 --> 00:00:30,160 'But at just the right distance, 8 00:00:30,160 --> 00:00:31,960 'you get this. 9 00:00:33,960 --> 00:00:37,960 'A living, breathing world. 10 00:00:41,480 --> 00:00:44,640 'No other planet in the known universe 11 00:00:44,640 --> 00:00:49,320 'experiences seasons like our planet, Earth.' 12 00:00:49,320 --> 00:00:51,960 By the beginning of March, 13 00:00:51,960 --> 00:00:55,000 we in the north are turning towards the sun... 14 00:00:57,960 --> 00:01:00,960 '..and winter snow begins to melt. 15 00:01:04,960 --> 00:01:06,960 'Just a little at first. 16 00:01:09,480 --> 00:01:12,960 'Then more and more.' 17 00:01:17,960 --> 00:01:22,960 Until the flow of water becomes truly staggering. 18 00:01:26,960 --> 00:01:30,960 Every year, the returning sun 19 00:01:30,960 --> 00:01:34,960 melts over ten million square miles of snow 20 00:01:34,960 --> 00:01:36,960 in the Northern Hemisphere. 21 00:01:38,960 --> 00:01:42,640 'Allowing the land to reawaken... 22 00:01:44,960 --> 00:01:46,960 '..and bringing new life. 23 00:01:49,960 --> 00:01:54,960 'While in the Southern Hemisphere, life braces itself 24 00:01:54,960 --> 00:01:56,960 'for far tougher times ahead. 25 00:01:58,960 --> 00:02:02,960 'In more than 60 locations across the globe, 26 00:02:02,960 --> 00:02:07,960 'we follow the world's most spectacular animals... 27 00:02:09,960 --> 00:02:12,960 '..and reveal the struggles... 28 00:02:14,960 --> 00:02:17,000 '..and opportunities 29 00:02:17,000 --> 00:02:19,480 'of spring. 30 00:02:20,960 --> 00:02:25,960 'The most magical part of our journey around the sun. 31 00:02:56,960 --> 00:03:00,960 'This is going to be an extraordinary day. 32 00:03:03,960 --> 00:03:06,960 'No matter where you are in the world... 33 00:03:10,320 --> 00:03:13,960 '..there will be 12 hours of daylight... 34 00:03:15,800 --> 00:03:17,960 '..and 12 hours of darkness. 35 00:03:21,320 --> 00:03:24,960 'The spring equinox has arrived. 36 00:03:27,480 --> 00:03:30,960 'Incredibly, there is one animal 37 00:03:30,960 --> 00:03:34,960 'that can detect this unique celestial moment. 38 00:03:45,960 --> 00:03:47,960 'A leatherback turtle. 39 00:03:50,480 --> 00:03:53,960 'She has a translucent spot on her head 40 00:03:53,960 --> 00:03:57,320 'that acts like a skylight, 41 00:03:57,320 --> 00:04:00,960 'letting light shine through her skull, 42 00:04:00,960 --> 00:04:03,960 'directly onto her brain. 43 00:04:04,960 --> 00:04:08,960 'And now, after two decades of wandering the oceans, 44 00:04:08,960 --> 00:04:13,960 'it compels her to return to the beach where she hatched... 45 00:04:17,960 --> 00:04:20,960 '..and lay eggs of her own. 46 00:04:41,960 --> 00:04:44,320 'As graceful as they are in water, 47 00:04:44,320 --> 00:04:47,960 'leatherbacks are poorly-adapted for moving on land. 48 00:04:51,960 --> 00:04:55,160 'The largest turtles in the world, 49 00:04:55,160 --> 00:04:56,960 'over a half a tonne, 50 00:04:56,960 --> 00:04:59,960 'and as a big as a two-seater sofa. 51 00:05:04,160 --> 00:05:09,960 'Every inch is won by extreme labour. 52 00:05:17,640 --> 00:05:20,160 'It's going to be a tough night. 53 00:05:35,960 --> 00:05:39,960 'Her eggs are very sensitive to temperature. 54 00:05:40,960 --> 00:05:44,960 'To prevent them from overheating, she must dig deep. 55 00:05:53,640 --> 00:05:58,000 'Finally, after more than an hour, her nest is ready. 56 00:06:11,960 --> 00:06:14,960 'She lays around 80 eggs... 57 00:06:16,000 --> 00:06:18,960 '..each slightly bigger than a golf ball. 58 00:06:23,800 --> 00:06:25,320 'Now safely buried, 59 00:06:25,320 --> 00:06:27,960 'they will hatch in two months. 60 00:06:29,960 --> 00:06:33,960 'But she won't be here to see her babies emerge. 61 00:06:45,000 --> 00:06:49,960 'Exhausted, she must recoup her energy 62 00:06:49,960 --> 00:06:53,960 'by going to feed in the richest part of the ocean... 63 00:06:55,960 --> 00:06:59,960 '..which now lies thousands of miles north. 64 00:07:02,960 --> 00:07:07,480 'As the sun moves further over the Northern Hemisphere, 65 00:07:07,480 --> 00:07:11,640 'days now become longer than nights. 66 00:07:19,960 --> 00:07:22,960 'And light fuels growth. 67 00:07:29,960 --> 00:07:33,800 'The land bursts with colour. 68 00:07:37,960 --> 00:07:39,640 'And surprisingly, 69 00:07:39,640 --> 00:07:43,000 'some of the most spectacular spring blooms of all 70 00:07:43,000 --> 00:07:46,960 'are found right in the middle of the desert. 71 00:07:49,160 --> 00:07:50,960 'Since December, 72 00:07:50,960 --> 00:07:54,960 'day length here has increased by two hours. 73 00:07:55,960 --> 00:07:59,960 'The solar energy reaching the ground has almost doubled. 74 00:08:00,960 --> 00:08:04,960 'And with the Earth still moist from winter rains, 75 00:08:04,960 --> 00:08:07,960 'conditions for growth are perfect. 76 00:08:11,960 --> 00:08:14,960 'And now these nectar-laden flowers 77 00:08:14,960 --> 00:08:17,960 'attract new life from miles around. 78 00:08:22,960 --> 00:08:27,960 'Including one of the most beautiful birds in the desert. 79 00:08:38,000 --> 00:08:41,960 'A male Costa's hummingbird... 80 00:08:45,960 --> 00:08:48,960 '..preparing for his busiest time of the year. 81 00:08:54,800 --> 00:08:58,960 'Without nectar, he would die of starvation within a few hours. 82 00:09:03,960 --> 00:09:07,960 'Hummingbirds have the fastest metabolisms of any animal. 83 00:09:12,480 --> 00:09:16,800 'His tiny heart beats more than ten times a second. 84 00:09:21,640 --> 00:09:23,960 'And just a few yards away 85 00:09:23,960 --> 00:09:27,960 'is someone that can make it beat faster still. 86 00:09:30,960 --> 00:09:34,960 'A female Costa's hummingbird. 87 00:09:37,960 --> 00:09:40,160 'She may look a little drab... 88 00:09:41,960 --> 00:09:44,960 '..but she is the object of his desire. 89 00:09:47,480 --> 00:09:49,640 ''The only problem is, 90 00:09:49,640 --> 00:09:55,960 'despite his fancy feathers, she doesn't appear to fancy him.' 91 00:09:58,960 --> 00:10:01,960 'Thankfully, he has a trick up his sleeve. 92 00:10:02,960 --> 00:10:06,960 'One of nature's most extraordinary courtship displays. 93 00:10:13,960 --> 00:10:18,960 'Best admired with a full frontal. 94 00:10:31,960 --> 00:10:34,960 'Positioned at just the right angle to the sun... 95 00:10:35,960 --> 00:10:38,960 '..with feathers splayed... 96 00:10:40,640 --> 00:10:43,160 '..he is absolutely dazzling. 97 00:10:46,960 --> 00:10:49,960 'Having a purple octopus waved in your face 98 00:10:49,960 --> 00:10:52,000 'might not be your thing, 99 00:10:52,000 --> 00:10:56,960 'but the perfection of his plumage shows his quality. 100 00:10:58,960 --> 00:11:00,960 'And it works for her.' 101 00:11:07,960 --> 00:11:10,320 'In just over a month, 102 00:11:10,320 --> 00:11:15,960 'her chicks will have hatched, grown up and flown the nest. 103 00:11:22,960 --> 00:11:27,480 'Spring comes early in the desert, and it doesn't last long. 104 00:11:31,960 --> 00:11:34,160 'But further up in the Northern Hemisphere, 105 00:11:34,160 --> 00:11:36,960 'it's only just begun. 106 00:11:38,960 --> 00:11:44,640 'The greatest baby boom on Earth is still to come. 107 00:11:50,960 --> 00:11:54,960 'In the north, spring is now taking hold. 108 00:11:55,960 --> 00:11:57,960 'The strengthening sun 109 00:11:57,960 --> 00:12:01,960 'fuels billions of tonnes of new plant growth. 110 00:12:03,960 --> 00:12:08,960 'It sends a pulse of energy coursing through the food chain, 111 00:12:08,960 --> 00:12:12,800 'triggering an enormous baby boom. 112 00:12:16,960 --> 00:12:20,960 'A surge of easy-to-catch prey 113 00:12:20,960 --> 00:12:22,960 'makes this the ideal time 114 00:12:22,960 --> 00:12:25,960 'for hunters to raise their families, too. 115 00:12:31,480 --> 00:12:33,960 'But closer to the equator, 116 00:12:33,960 --> 00:12:37,480 'predators aren't having it so easy. 117 00:12:41,000 --> 00:12:42,960 'East Africa, 118 00:12:42,960 --> 00:12:45,960 'home to the planet's greatest population 119 00:12:45,960 --> 00:12:47,960 'of large carnivores. 120 00:12:57,960 --> 00:12:59,960 'Five months ago, 121 00:12:59,960 --> 00:13:02,960 'this landscape was a predator's paradise. 122 00:13:05,960 --> 00:13:08,960 'A million wildebeest. 123 00:13:09,960 --> 00:13:12,960 '300,000 zebras. 124 00:13:12,960 --> 00:13:15,960 'And 200,000 gazelles. 125 00:13:19,960 --> 00:13:21,960 'Nearly all gone. 126 00:13:21,960 --> 00:13:26,960 'And the great migration won't return until summer. 127 00:13:30,960 --> 00:13:34,320 'Now, only the locals remain. 128 00:13:37,960 --> 00:13:40,960 'Experienced and wary. 129 00:13:46,960 --> 00:13:50,960 'Spring can be a tough time for a cheetah mum. 130 00:13:52,960 --> 00:13:56,960 'Her two six-month-old cubs need to be fed every day 131 00:13:56,960 --> 00:13:59,000 'or they'll begin to starve. 132 00:14:06,960 --> 00:14:09,640 'But she must pick her moment... 133 00:14:10,960 --> 00:14:13,960 '..conserve her energy. 134 00:14:18,960 --> 00:14:21,960 'The cubs have a different agenda. 135 00:14:23,960 --> 00:14:29,320 'Playing is how they learn which animals are impossible to catch. 136 00:14:33,960 --> 00:14:36,480 'And which ones fight back. 137 00:14:43,960 --> 00:14:46,960 'With practice, they will be able to accelerate 138 00:14:46,960 --> 00:14:48,960 'faster than most sports cars... 139 00:14:50,960 --> 00:14:54,960 '..and reach speeds of up to 65mph. 140 00:14:57,960 --> 00:14:59,960 'But not yet. 141 00:14:59,960 --> 00:15:03,160 'Right now, they're just being a pain in the... 142 00:15:04,800 --> 00:15:05,960 '..tail. 143 00:15:15,640 --> 00:15:17,160 'Enough with the play. 144 00:15:20,960 --> 00:15:22,960 'It's time to go to work. 145 00:15:36,960 --> 00:15:39,640 'As far as we know, 146 00:15:39,640 --> 00:15:42,960 'cheetahs are the fastest land animals to have ever existed. 147 00:15:57,960 --> 00:16:00,960 'They can execute turns 148 00:16:00,960 --> 00:16:04,960 'at speeds that would break the legs of other animals. 149 00:16:26,480 --> 00:16:29,960 'But like any high-performance athlete, 150 00:16:29,960 --> 00:16:35,320 'success or failure is separated by the tiniest of margins. 151 00:16:37,960 --> 00:16:41,160 'The hunter's dinner is never guaranteed... 152 00:16:42,960 --> 00:16:45,480 '..especially at this time of year. 153 00:16:47,960 --> 00:16:50,960 'In many ways, the prey have it easier. 154 00:16:52,160 --> 00:16:55,960 'Their food grows everywhere. 155 00:16:55,960 --> 00:17:00,960 'But it is dependent on one crucial resource. 156 00:17:04,640 --> 00:17:05,960 'Water. 157 00:17:11,960 --> 00:17:13,960 'Since winter, the tropical rain band 158 00:17:13,960 --> 00:17:16,960 'has been steadily moving up the continent... 159 00:17:18,960 --> 00:17:23,960 '..forming wherever the sun shines hottest on the Earth's surface. 160 00:17:24,960 --> 00:17:28,000 'It brings life to the dry lands of Africa. 161 00:17:29,960 --> 00:17:32,640 'But as the rains move north... 162 00:17:33,960 --> 00:17:35,960 '..further south... 163 00:17:36,960 --> 00:17:39,960 '..conditions are becoming critical. 164 00:18:01,960 --> 00:18:04,960 'The water holes are shrinking... 165 00:18:05,960 --> 00:18:07,960 '..getting crowded... 166 00:18:14,960 --> 00:18:17,960 '..and more dangerous. 167 00:18:22,960 --> 00:18:25,960 'Even the elephants are vulnerable. 168 00:18:28,960 --> 00:18:30,960 'Especially the youngsters. 169 00:18:38,960 --> 00:18:42,960 'The old matriarch leader of this group 170 00:18:42,960 --> 00:18:44,960 'knows it's time to move on. 171 00:18:48,800 --> 00:18:51,960 'She has made many journeys in search of water 172 00:18:51,960 --> 00:18:53,960 'in her 50 years, 173 00:18:53,960 --> 00:18:56,960 'and can even remember routes made 174 00:18:56,960 --> 00:19:00,160 'during extreme droughts decades ago. 175 00:19:03,960 --> 00:19:05,960 'And now this four-month-old baby 176 00:19:05,960 --> 00:19:10,960 'must learn the way as he begins his first migration. 177 00:19:13,480 --> 00:19:18,960 'Indeed, much of an elephant's behaviour is learned. 178 00:19:19,960 --> 00:19:25,960 'From birth to adulthood, their brains almost triple in size, 179 00:19:25,960 --> 00:19:29,960 'the greatest increase of any animal apart from us. 180 00:19:32,160 --> 00:19:35,160 'The good times are over. 181 00:19:37,480 --> 00:19:41,960 'Ahead, only a thirsty, gruelling march.' 182 00:19:50,960 --> 00:19:54,960 'The red-billed quelea are also heading off. 183 00:19:56,960 --> 00:20:01,960 'They follow the rains and the pulse of fresh grass seed. 184 00:20:03,640 --> 00:20:06,960 'And they do so in their millions. 185 00:20:10,480 --> 00:20:13,160 'The most abundant wild bird in the world. 186 00:20:15,960 --> 00:20:20,960 'The key to their success is a super-fast breeding cycle, 187 00:20:20,960 --> 00:20:24,960 'little more than three weeks from laying eggs to chicks flying. 188 00:20:26,960 --> 00:20:29,960 'Ready to leave when conditions get tough. 189 00:20:36,640 --> 00:20:38,960 'Not everyone has that option. 190 00:20:40,960 --> 00:20:45,960 'In the far south, the darkness is creeping in. 191 00:20:47,960 --> 00:20:50,960 'The sun sinking lower. 192 00:20:52,480 --> 00:20:54,960 'The land growing colder. 193 00:21:05,000 --> 00:21:08,160 'This four-month-old king penguin chick 194 00:21:08,160 --> 00:21:09,960 'is stuck here. 195 00:21:12,960 --> 00:21:14,960 'She won't be ready to leave the island 196 00:21:14,960 --> 00:21:16,960 'for another eight months. 197 00:21:18,960 --> 00:21:22,960 'So she must prepare for the coming cold. 198 00:21:25,320 --> 00:21:29,800 'Since hatching, she's grown from a tiny, naked chick, 199 00:21:29,800 --> 00:21:32,800 'weighing less than 250g, 200 00:21:32,800 --> 00:21:37,960 'into this plump, downy youngster of nearly 12 kilos. 201 00:21:40,960 --> 00:21:45,960 'Just as well - it's the coldest day of the year so far. 202 00:21:48,960 --> 00:21:52,960 'And something new and strange is happening.' 203 00:22:18,960 --> 00:22:21,960 'Curiosity gets the better of her. 204 00:22:42,960 --> 00:22:45,960 'The nasty side of town. 205 00:22:47,960 --> 00:22:50,960 'The source of all this flying fluff? 206 00:22:52,960 --> 00:22:53,960 'Not snow. 207 00:22:55,960 --> 00:22:58,960 'Manky, moulting macaroni penguins. 208 00:23:14,960 --> 00:23:17,320 'And there's something else here. 209 00:23:19,320 --> 00:23:20,960 'Monsters. 210 00:23:22,960 --> 00:23:25,640 'These are giant petrels. 211 00:23:28,160 --> 00:23:31,960 'Three feet tall, and as heavy as a Christmas turkey. 212 00:23:35,960 --> 00:23:39,960 'The stress of moulting makes some macaronis weak. 213 00:23:42,160 --> 00:23:45,800 'But if you show weakness here... 214 00:23:47,960 --> 00:23:50,960 '..there is no mercy.' 215 00:24:11,960 --> 00:24:16,960 'Giant petrels don't miss any opportunity. 216 00:24:21,960 --> 00:24:26,960 'Against these relentless killers, a chick doesn't stand a chance. 217 00:24:28,960 --> 00:24:31,960 'And she's just been spotted. 218 00:24:41,160 --> 00:24:45,640 'When a giant petrel sizes you up like this, 219 00:24:45,640 --> 00:24:49,960 'it's time to get out of here. 220 00:24:53,960 --> 00:24:57,800 'Her nemesis is coming for her.' 221 00:25:31,480 --> 00:25:35,640 'But the giant petrel has underestimated the kings. 222 00:25:39,960 --> 00:25:45,960 'Twice as big as the macaronis, they can stand up to this bully. 223 00:25:58,960 --> 00:26:02,640 'It's all too much for the giant petrel. 224 00:26:08,160 --> 00:26:11,480 'Finally, the chick can relax. 225 00:26:14,800 --> 00:26:16,960 'But not too much. 226 00:26:16,960 --> 00:26:19,960 'Soon, her parents will be gone for weeks, 227 00:26:19,960 --> 00:26:22,960 'even months, on end. 228 00:26:22,960 --> 00:26:25,480 'As the water gets colder, 229 00:26:25,480 --> 00:26:27,960 'the ocean currents shift 230 00:26:27,960 --> 00:26:30,960 'and feeding areas move further away. 231 00:26:32,960 --> 00:26:35,960 'She will grow hungrier, weaker... 232 00:26:37,160 --> 00:26:40,160 '..and she'll be alone. 233 00:26:50,480 --> 00:26:53,800 'While conditions in the south grow harsher... 234 00:26:54,960 --> 00:26:58,960 '..the Northern Hemisphere is in the full flush of spring. 235 00:27:09,960 --> 00:27:13,960 'And here, in this seasonal rainforest, 236 00:27:13,960 --> 00:27:17,960 'the fresh growth feeds all kinds of animals. 237 00:27:20,960 --> 00:27:26,320 'Including one of the most striking monkeys on the planet. 238 00:27:50,480 --> 00:27:53,960 'Red-shanked doucs. 239 00:27:57,960 --> 00:28:02,960 'Timed with the burst of fresh spring leaves and flowers, 240 00:28:02,960 --> 00:28:06,960 'these doucs are having a baby boom of their own. 241 00:28:11,000 --> 00:28:12,960 'Only four years old, 242 00:28:12,960 --> 00:28:16,000 'this is the youngest mum in the community. 243 00:28:18,320 --> 00:28:21,960 'And this is her first baby. 244 00:28:23,000 --> 00:28:25,960 'Just days old. 245 00:28:34,960 --> 00:28:38,960 'Right now, it's a worrying time for Mum. 246 00:28:40,960 --> 00:28:43,480 'Newborns make easy targets... 247 00:28:44,960 --> 00:28:47,960 '..for all kinds of predators. 248 00:29:13,960 --> 00:29:18,640 'But too much protection can be stifling. 249 00:29:23,800 --> 00:29:25,960 'He needs to learn key skills, 250 00:29:25,960 --> 00:29:29,960 'like how to move through the forest. 251 00:29:35,960 --> 00:29:40,480 'Doucs make some of the longest leaps of all monkeys, 252 00:29:40,480 --> 00:29:43,160 'frequently exceeding ten metres. 253 00:29:46,960 --> 00:29:50,960 'You can't do this without a lot of practice. 254 00:29:55,320 --> 00:29:58,960 'Sometimes, a mum has to let go. 255 00:30:10,960 --> 00:30:15,960 'We see spring as a time of relief after a long winter. 256 00:30:17,960 --> 00:30:22,960 'Yet for many animals, this is a time of great stress. 257 00:30:25,960 --> 00:30:31,960 'Never will their babies be more needy and more vulnerable. 258 00:30:32,960 --> 00:30:35,960 'And never will parents have to be more vigilant. 259 00:30:38,960 --> 00:30:42,960 'But all a mum can do is take it one day at a time. 260 00:30:57,960 --> 00:30:59,960 'At least she's bringing up baby 261 00:30:59,960 --> 00:31:02,960 'in the relative comfort of the tropics. 262 00:31:02,960 --> 00:31:06,960 'A little further north, just beyond the Himalayas, 263 00:31:06,960 --> 00:31:09,960 'it's a different story. 264 00:31:22,960 --> 00:31:25,000 'The Tibetan Plateau. 265 00:31:28,160 --> 00:31:30,960 'Covering nearly a million square miles, 266 00:31:30,960 --> 00:31:35,960 'and averaging over 4,000 metres high, 267 00:31:35,960 --> 00:31:40,480 'it's the largest and highest plateau in the world. 268 00:31:43,480 --> 00:31:46,960 'With little more than half the oxygen at sea level, 269 00:31:46,960 --> 00:31:49,960 'the air leaves you gasping. 270 00:31:50,960 --> 00:31:55,960 'Winter temperatures can plummet to minus 20 degrees Celsius. 271 00:31:58,960 --> 00:32:02,960 'Not many animals have adapted to life up here. 272 00:32:06,960 --> 00:32:08,960 'This is one of the few. 273 00:32:10,960 --> 00:32:12,320 'A Tibetan fox. 274 00:32:14,800 --> 00:32:17,000 'A mere 2.5 million years 275 00:32:17,000 --> 00:32:20,960 'set it apart from our red fox. 276 00:32:20,960 --> 00:32:25,160 'Yet it's enough to have evolved an extraordinarily wide gape. 277 00:32:32,960 --> 00:32:38,160 'An adaptation for a diet consisting almost entirely of these animals. 278 00:32:42,960 --> 00:32:45,960 'Thanks to a surge of spring breeding, 279 00:32:45,960 --> 00:32:48,960 'plateau pika are everywhere. 280 00:32:49,960 --> 00:32:53,960 'But they have hundreds of boltholes. 281 00:32:59,960 --> 00:33:01,960 'To catch one, you have to be... 282 00:33:04,960 --> 00:33:06,960 '..patient.' 283 00:33:54,960 --> 00:33:58,800 'A lot of work for such a small snack. 284 00:34:00,960 --> 00:34:03,160 'And she's not even going to eat it. 285 00:34:07,640 --> 00:34:11,960 'It's for her three eight-week-old cubs. 286 00:34:19,960 --> 00:34:20,960 'In fox families, 287 00:34:20,960 --> 00:34:24,960 'fathers usually stick around to help. 288 00:34:26,960 --> 00:34:30,960 'But Dad hasn't been seen for weeks. 289 00:34:34,960 --> 00:34:40,960 'Up here, conditions are so harsh, lives are often cut short. 290 00:34:42,960 --> 00:34:46,960 'Keeping the family fed is now a real struggle. 291 00:34:54,960 --> 00:34:57,960 'By the time the cubs are up... 292 00:34:58,960 --> 00:35:01,640 '..Mum's already out hunting. 293 00:35:05,800 --> 00:35:08,960 'All this play is hungry work. 294 00:35:12,960 --> 00:35:14,960 'But for some reason, 295 00:35:14,960 --> 00:35:17,480 'breakfast is late. 296 00:35:24,960 --> 00:35:27,960 'Constantly sprinting after prey 297 00:35:27,960 --> 00:35:30,960 'over potholed ground 298 00:35:30,960 --> 00:35:32,960 'has taken its toll. 299 00:35:37,960 --> 00:35:42,960 'An injury as serious as this could stop her hunting. 300 00:35:47,960 --> 00:35:52,000 'And that means starvation for the whole family.' 301 00:36:11,960 --> 00:36:16,160 'Though clearly in pain, Mum is off hunting again. 302 00:36:21,960 --> 00:36:25,800 'With cubs to feed, she has no choice. 303 00:36:32,320 --> 00:36:37,640 'But sometimes, adversity brings out the best in you. 304 00:37:10,000 --> 00:37:13,320 'She's found her A-game. 305 00:37:24,960 --> 00:37:27,960 'Perhaps her luck is returning. 306 00:37:35,480 --> 00:37:39,960 'Thanks to Mum's extraordinary determination, 307 00:37:39,960 --> 00:37:43,800 'the cubs should keep growing strong. 308 00:37:44,960 --> 00:37:47,000 'With so many mouths to feed, 309 00:37:47,000 --> 00:37:51,960 'spring can be the most challenging time of year. 310 00:38:04,960 --> 00:38:06,480 'This cheetah mum... 311 00:38:07,960 --> 00:38:10,960 '..desperately needs a change in fortune. 312 00:38:40,960 --> 00:38:43,480 'No matter how hard she tries... 313 00:38:46,960 --> 00:38:49,960 '..it always ends in frustration. 314 00:38:51,960 --> 00:38:54,800 'Mum is exhausted. 315 00:38:54,800 --> 00:38:57,960 'She can't afford any more failures. 316 00:39:06,960 --> 00:39:10,000 'Hyenas will kill cheetah cubs. 317 00:39:13,960 --> 00:39:17,960 'They're too big to beat in a fight. 318 00:39:19,960 --> 00:39:23,320 'The whole family has to be very careful. 319 00:39:25,960 --> 00:39:27,960 'All she can do 320 00:39:27,960 --> 00:39:32,960 'is stay by her cubs and hope the danger passes. 321 00:39:41,960 --> 00:39:45,960 'The threat from lions and hyenas is constant. 322 00:39:46,960 --> 00:39:49,160 'But she can't hide forever. 323 00:39:49,160 --> 00:39:52,480 'Her family needs to eat. 324 00:39:57,960 --> 00:40:00,960 'A male impala. 325 00:40:02,960 --> 00:40:07,960 'Cheetahs usually avoid such large, heavily-armed prey. 326 00:40:08,960 --> 00:40:12,960 'The risk of injury is just too high. 327 00:40:17,960 --> 00:40:20,800 'But not for this mum.' 328 00:41:15,960 --> 00:41:19,960 'For the first time, her cubs actually help. 329 00:41:35,800 --> 00:41:38,960 'Around 80% of cheetah cubs here 330 00:41:38,960 --> 00:41:41,960 'succumb to predators or starvation 331 00:41:41,960 --> 00:41:44,960 'before the reach their first birthday. 332 00:41:46,960 --> 00:41:50,160 'Her cubs still have a long way to go... 333 00:41:51,960 --> 00:41:53,960 '..but with every kill, 334 00:41:53,960 --> 00:41:56,960 'every passing day, 335 00:41:56,960 --> 00:41:59,960 'their chances improve. 336 00:42:13,960 --> 00:42:17,960 'Spring in the north is drawing to an end. 337 00:42:20,640 --> 00:42:22,960 'But here, on this beach, 338 00:42:22,960 --> 00:42:26,960 'it still has one final wonder to offer. 339 00:42:48,960 --> 00:42:50,960 'For eight weeks... 340 00:42:51,960 --> 00:42:53,640 '..the leatherback eggs 341 00:42:53,640 --> 00:42:56,960 'have been gently incubated by the sun. 342 00:42:59,960 --> 00:43:04,160 'Now the baby turtles are beginning their own journey. 343 00:43:06,160 --> 00:43:10,480 'But everything will depend on the next few minutes. 344 00:43:20,160 --> 00:43:23,960 'Black vultures have been waiting for this moment. 345 00:43:49,960 --> 00:43:51,480 'Their mum's sacrifice, 346 00:43:51,480 --> 00:43:53,960 'her toil on the beach, 347 00:43:53,960 --> 00:43:55,960 'may come to nothing. 348 00:44:01,960 --> 00:44:05,000 'But if this hatchling can make it to the sea, 349 00:44:05,000 --> 00:44:09,480 'the odds of reaching adulthood rise dramatically. 350 00:44:31,800 --> 00:44:34,960 'He's passed his first trial. 351 00:44:36,960 --> 00:44:40,960 'With luck, he may go on to live for over 50 years... 352 00:44:42,480 --> 00:44:45,960 '..and cover tens of thousands of miles.' 353 00:44:51,960 --> 00:44:52,960 Within a month, 354 00:44:52,960 --> 00:44:56,960 some of the leatherback turtles that nested in Trinidad 355 00:44:56,960 --> 00:44:58,960 could have come as far north as here, 356 00:44:58,960 --> 00:45:01,960 in Iceland, to feed. 357 00:45:03,640 --> 00:45:07,960 'Soon, the sun will deliver more energy here 358 00:45:07,960 --> 00:45:09,960 'than the hottest part of the tropics.' 359 00:45:11,960 --> 00:45:14,320 We're about to begin summer. 360 00:45:14,320 --> 00:45:18,000 The hottest, most intense, 361 00:45:18,000 --> 00:45:20,960 and most vibrant part 362 00:45:20,960 --> 00:45:23,960 of our journey around the sun. 363 00:45:25,640 --> 00:45:27,000 'Right across the globe... 364 00:45:28,960 --> 00:45:32,960 '..animals will face new challenges... 365 00:45:34,960 --> 00:45:37,800 '..and unique opportunities... 366 00:45:38,960 --> 00:45:42,640 '..during the most extreme season 367 00:45:42,640 --> 00:45:44,960 'on planet Earth.' 368 00:45:53,960 --> 00:45:56,960 Subtitles by accessibility@itv.com