1 00:00:03,164 --> 00:00:05,164 (THEME MUSIC PLAYING) 2 00:00:33,564 --> 00:00:34,924 (BIRDS CHIRPING) 3 00:00:35,004 --> 00:00:37,764 DAVID ATTENBOROUGH: One quarter of all the land on Earth 4 00:00:37,844 --> 00:00:41,404 is covered by a single, remarkable type of plant. 5 00:00:47,804 --> 00:00:52,164 Almost indestructible, it can grow two feet in a day... 6 00:00:58,604 --> 00:01:01,924 And be tall enough to hide a giant. 7 00:01:02,604 --> 00:01:04,284 (GRUNTING) 8 00:01:06,244 --> 00:01:08,564 That plant is grass, 9 00:01:08,644 --> 00:01:11,924 and the world it creates is truly unique. 10 00:01:25,484 --> 00:01:29,204 The grass in northern India is the tallest on the planet, 11 00:01:29,364 --> 00:01:33,404 home to some of the most impressive creatures to tread the Earth. 12 00:01:37,964 --> 00:01:39,244 (GRUNTS) 13 00:01:47,164 --> 00:01:48,324 (TRUMPETS) 14 00:01:48,404 --> 00:01:50,524 These are the good times, 15 00:01:50,604 --> 00:01:54,244 but in just a few months, all this fresh growth will be gone, 16 00:01:54,804 --> 00:01:57,884 and the animals will be forced to move on. 17 00:02:00,604 --> 00:02:05,204 That is the way things are on grasslands across the planet. 18 00:02:08,884 --> 00:02:13,084 A cycle of abundance, destruction and rebirth 19 00:02:13,444 --> 00:02:15,764 that affects every creature that lives here. 20 00:02:23,044 --> 00:02:24,964 (ELEPHANTS GRUNTING) 21 00:02:30,684 --> 00:02:35,284 The largest grassland on Earth, the vast Eurasian Steppe, 22 00:02:35,724 --> 00:02:39,124 stretches one third of the way around our planet. 23 00:02:43,444 --> 00:02:48,604 Spring rain has brought fresh grass, and with it, new life. 24 00:02:52,804 --> 00:02:57,444 A relic from the Ice Age, a baby Saiga antelope, 25 00:02:57,724 --> 00:02:59,524 just three hours old. 26 00:03:02,724 --> 00:03:04,964 His only company, his twin. 27 00:03:06,284 --> 00:03:10,884 Until they can stand, their mother has left them hidden in the grass. 28 00:03:18,604 --> 00:03:22,524 They should be safe, as long as they remain quiet. 29 00:03:24,684 --> 00:03:25,684 (CALLS) 30 00:03:27,524 --> 00:03:30,404 For these calves, the clock is already ticking. 31 00:03:31,964 --> 00:03:36,604 Their herd will soon be moving on, seeking the freshest new grass. 32 00:03:40,324 --> 00:03:41,604 (CALLS) 33 00:03:53,884 --> 00:03:58,444 Their lanky legs are a sure sign that they're built for a life on the move. 34 00:04:22,804 --> 00:04:25,724 Saiga always give birth to twins, 35 00:04:25,804 --> 00:04:29,324 so their numbers grow rapidly just when grass is plentiful. 36 00:04:32,724 --> 00:04:36,084 Their bizarrely shaped nose can detect fresh growth 37 00:04:36,404 --> 00:04:38,364 from hundreds of miles away. 38 00:04:42,284 --> 00:04:44,084 (SAIGAS BAWLING) 39 00:04:50,124 --> 00:04:53,364 The young twins will now begin the nomadic life 40 00:04:53,564 --> 00:04:57,644 they share with most animals on the world's open plains. 41 00:05:12,244 --> 00:05:13,444 (THUNDER RUMBLING) 42 00:05:18,804 --> 00:05:24,404 Grasslands occur where rain is too sporadic for forests to exist. 43 00:05:34,564 --> 00:05:37,924 The rain that a grassland needs to survive for a year 44 00:05:38,204 --> 00:05:40,284 might arrive all at once. 45 00:05:44,164 --> 00:05:45,284 (LIGHTNING CRACKS) 46 00:06:00,884 --> 00:06:05,884 Storms like these can release 12 inches of rain in 24 hours. 47 00:06:05,964 --> 00:06:07,484 (HEAVY RAINFALL) 48 00:06:16,644 --> 00:06:19,284 Not much fun if you're out in it. 49 00:06:31,004 --> 00:06:34,284 Eventually the earth can't soak up any more, 50 00:06:34,884 --> 00:06:36,404 (THUNDER CRACKING) 51 00:06:37,164 --> 00:06:40,604 and the grassland undergoes a radical change. 52 00:06:41,524 --> 00:06:43,364 (WATER FLOWING) 53 00:06:47,444 --> 00:06:51,924 Many plants would drown here, but grasses thrive. 54 00:06:55,044 --> 00:06:56,164 They grow so fast, 55 00:06:56,244 --> 00:06:59,604 their leaves quickly rise above the water and into the sunlight. 56 00:07:04,244 --> 00:07:06,004 Here in southern Africa, 57 00:07:06,084 --> 00:07:10,644 water transforms one of the most remarkable grasslands on Earth, 58 00:07:13,204 --> 00:07:14,244 the Okavango. 59 00:07:17,964 --> 00:07:22,284 Every year, 5, 000 square miles of grassland are flooded. 60 00:07:30,244 --> 00:07:34,244 For one pride of lions, this poses a major problem. 61 00:07:36,564 --> 00:07:38,964 There may be plenty of prey around, 62 00:07:39,044 --> 00:07:41,724 but lions struggle to run it down in water. 63 00:07:48,804 --> 00:07:53,644 The pride has three-month-old cubs. They've never seen water before. 64 00:07:54,364 --> 00:07:55,844 (CUBS MEOWING) 65 00:07:57,564 --> 00:07:59,684 If their mothers don't make a kill soon, 66 00:08:00,284 --> 00:08:02,804 the cubs might not survive the week. 67 00:08:03,724 --> 00:08:04,844 (YOWLS) 68 00:08:12,204 --> 00:08:17,804 But fuelled by the flood, the eruption of grass attracts new possible prey. 69 00:08:21,004 --> 00:08:24,044 Buffalo arrive in herds 2, 000 strong. 70 00:08:30,404 --> 00:08:31,444 (GRUNTS) 71 00:08:31,524 --> 00:08:34,444 Powerful, aggressive and united, 72 00:08:34,844 --> 00:08:37,724 they're the most dangerous animal a lion can face. 73 00:09:01,924 --> 00:09:02,924 (BUFFALO GRUNTS) 74 00:09:15,084 --> 00:09:17,284 The biggest bulls don't run. 75 00:09:19,604 --> 00:09:22,884 They're simply too huge to be scared of lions. 76 00:09:25,364 --> 00:09:30,244 At 900 kilos, he weighs more than all five lionesses combined. 77 00:09:34,684 --> 00:09:37,124 The pride do have numbers on their side, 78 00:09:38,764 --> 00:09:41,604 but one sweep of his horns could be deadly. 79 00:09:55,404 --> 00:09:59,684 One distracts the bull up front, while her sisters attack from behind. 80 00:10:10,564 --> 00:10:12,844 The cats must somehow topple the buffalo, 81 00:10:13,044 --> 00:10:16,204 but with swamp under foot, they can't get any traction. 82 00:10:59,284 --> 00:11:00,884 The bull is weakening, 83 00:11:01,764 --> 00:11:03,924 but the lions are tiring, too. 84 00:11:08,924 --> 00:11:12,564 It's now a battle of will as much as strength. 85 00:11:15,724 --> 00:11:19,204 To live, the bull must somehow shake off the lioness. 86 00:11:21,324 --> 00:11:23,324 (DRAMATIC INSTRUMENTAL MUSIC) 87 00:11:57,044 --> 00:11:58,604 The bull is wounded, 88 00:11:58,684 --> 00:12:02,404 but thanks to his two-inch-thick hide, he will recover. 89 00:12:08,244 --> 00:12:11,564 For the pride, these are hungry times. 90 00:12:11,644 --> 00:12:13,004 (CUB WHIMPERS) 91 00:12:19,684 --> 00:12:24,444 But, ultimately, once the water recedes, there will be new life, 92 00:12:25,444 --> 00:12:27,604 and new food to benefit all. 93 00:12:36,764 --> 00:12:40,684 In the right conditions, grasses have the extraordinary ability 94 00:12:40,764 --> 00:12:45,524 to grow from first shoots to flower in a matter of only days. 95 00:12:52,124 --> 00:12:56,324 Grasses become the miniature equivalents of fruiting trees. 96 00:13:02,044 --> 00:13:03,564 (CRICKET CHIRPS) 97 00:13:03,644 --> 00:13:06,204 And for creatures living within the grass, 98 00:13:06,284 --> 00:13:10,564 this is a landscape as vast and towering as any rainforest. 99 00:13:15,644 --> 00:13:18,524 And excellent place to build a tiny tree house 100 00:13:21,044 --> 00:13:22,244 for a harvest mouse. 101 00:13:27,364 --> 00:13:28,364 (SQUEAKS) 102 00:13:34,324 --> 00:13:38,444 During summer, European meadowlands are full of food, 103 00:13:41,804 --> 00:13:44,004 but only for those that can reach it. 104 00:14:00,404 --> 00:14:01,924 (STEM CRACKS) 105 00:14:02,444 --> 00:14:05,404 Climbing grass is harder than climbing trees, 106 00:14:05,564 --> 00:14:08,804 not least because their stems just won't stay still. 107 00:14:16,564 --> 00:14:19,924 Her prehensile tail acts like a fifth limb, 108 00:14:20,004 --> 00:14:24,004 so she's as agile as a monkey clambering around in a tree. 109 00:14:25,684 --> 00:14:26,684 (STEM CREAKS) 110 00:14:31,724 --> 00:14:33,004 And just as well, 111 00:14:33,364 --> 00:14:37,724 for the best food in this tiny forest is at the very top of its canopy. 112 00:14:48,484 --> 00:14:51,404 Feeding up here, she's exposed. 113 00:14:58,764 --> 00:14:59,924 A barn owl. 114 00:15:30,844 --> 00:15:32,684 Not her finest move... 115 00:15:36,484 --> 00:15:37,684 But it did the trick. 116 00:15:39,844 --> 00:15:43,244 Harvest mice seldom go all the way down to the ground. 117 00:15:46,524 --> 00:15:49,804 It's a tangled and dangerous world down here. 118 00:15:52,564 --> 00:15:54,684 (INSECTS CHITTERING) 119 00:16:03,044 --> 00:16:07,244 But she can read the pattern of the stems overhead like a map, 120 00:16:08,364 --> 00:16:10,244 and so find her way home. 121 00:16:18,284 --> 00:16:20,724 And not a minute too soon. 122 00:16:25,284 --> 00:16:27,324 There are mouths to feed. 123 00:16:36,404 --> 00:16:38,044 (SNIFFS) 124 00:16:41,084 --> 00:16:43,204 Her babies must fatten up quickly. 125 00:16:45,484 --> 00:16:49,964 They need to harvest the summer grasses while they're still rich with food. 126 00:16:58,404 --> 00:17:03,164 On the African savannah, too, seasonal grasses are filled with life, 127 00:17:03,684 --> 00:17:05,044 but it won't last long. 128 00:17:08,604 --> 00:17:11,884 Carmine bee-eaters are superb aerial hunters, 129 00:17:13,604 --> 00:17:17,044 experts at catching insects in midair. 130 00:17:24,404 --> 00:17:27,844 But they have no way of flushing their prey out of the grass. 131 00:17:35,844 --> 00:17:37,484 (INSECTS CHITTERING) 132 00:17:37,964 --> 00:17:41,164 Once alarmed, most insects stay put. 133 00:17:44,524 --> 00:17:48,164 The bee-eaters need someone to stir things up a bit. 134 00:17:48,244 --> 00:17:49,524 (CALLS) 135 00:17:54,084 --> 00:17:55,204 A kori bustard. 136 00:18:00,244 --> 00:18:02,564 It's the world's heaviest flying bird, 137 00:18:02,644 --> 00:18:05,284 so it should be bulky enough to kick up some insects. 138 00:18:11,604 --> 00:18:12,604 (INSECT BUZZING) 139 00:18:13,284 --> 00:18:14,284 Bingo! 140 00:18:17,244 --> 00:18:22,284 Until someone else comes along and cramps your style. 141 00:18:26,444 --> 00:18:27,444 (CHIRPS) 142 00:18:28,204 --> 00:18:32,244 Never mind, perhaps there are bigger opportunities ahead. 143 00:18:35,404 --> 00:18:37,044 What about an ostrich? 144 00:18:39,724 --> 00:18:41,044 The heaviest bird of all. 145 00:18:46,964 --> 00:18:50,604 This time there's more than enough transport to go around. 146 00:18:52,044 --> 00:18:53,044 (SQUAWKING) 147 00:19:00,644 --> 00:19:04,524 Soon, almost every ostrich has its own passenger. 148 00:19:12,284 --> 00:19:15,964 But free riders are only tolerated for so long. 149 00:19:22,524 --> 00:19:24,644 What the bee-eaters really need 150 00:19:24,724 --> 00:19:27,964 is a creature so big it won't even notice them. 151 00:19:32,684 --> 00:19:33,924 (GRUNTING) 152 00:19:38,164 --> 00:19:43,244 Nothing cuts a swathe through grass like an African bull elephant. 153 00:19:59,564 --> 00:20:03,564 The trick is to fly as close to the front of the giant as possible. 154 00:20:04,204 --> 00:20:07,364 They only have a split second to grab the prize. 155 00:20:17,044 --> 00:20:21,204 As more insects are stirred up, the competition intensifies. 156 00:20:24,124 --> 00:20:26,324 (FRENZIED CHIRPING) 157 00:20:43,164 --> 00:20:47,604 With summer drawing to a close, the race to stock up is on. 158 00:20:52,844 --> 00:20:57,884 Soon, the grass will wither, and this opportunity will have gone. 159 00:21:07,404 --> 00:21:09,964 As the dry season takes hold, 160 00:21:10,044 --> 00:21:12,684 food becomes increasingly thin on the ground. 161 00:21:15,364 --> 00:21:20,244 Now, only the most specialised predators on the plains can make a living. 162 00:21:25,764 --> 00:21:30,404 She may be spotted like a cheetah, but this cat is no sprinter. 163 00:21:43,124 --> 00:21:48,444 Instead, she has extra-long legs which give her a high vantage point. 164 00:21:59,524 --> 00:22:04,644 But a serval cat's main weapon are enormous radar ears. 165 00:22:05,084 --> 00:22:06,084 (GRASS RUSTLING) 166 00:22:08,844 --> 00:22:11,964 They help her pinpoint prey hiding in the grass. 167 00:22:20,804 --> 00:22:23,764 But the prey she seeks are canny. 168 00:22:27,564 --> 00:22:28,964 Southern vlei rats. 169 00:22:32,244 --> 00:22:35,604 They know that any sustained movement can give them away. 170 00:22:41,244 --> 00:22:43,724 So they move in short bursts. 171 00:22:43,844 --> 00:22:44,884 (RUSTLING) 172 00:22:51,644 --> 00:22:54,884 But even the slightest rustle will give her a clue. 173 00:22:55,084 --> 00:22:56,084 (RUSTLING) 174 00:23:17,164 --> 00:23:18,164 Warm. 175 00:23:24,724 --> 00:23:25,724 (RUSTLING) 176 00:23:27,324 --> 00:23:28,324 (RUSTLES) 177 00:23:30,524 --> 00:23:31,644 Warmer. 178 00:23:45,924 --> 00:23:47,004 Missed. 179 00:24:20,804 --> 00:24:21,804 (RUSTLING) 180 00:24:33,444 --> 00:24:34,444 (ANIMAL CALLS) 181 00:24:43,804 --> 00:24:44,804 (RUSTLING) 182 00:25:01,364 --> 00:25:02,364 (SQUEAKS) 183 00:25:06,484 --> 00:25:09,564 In better times, she could catch 10 a day, 184 00:25:10,924 --> 00:25:15,404 but now, with so few rodents around, she will have to go hungry. 185 00:25:17,764 --> 00:25:22,204 As drought intensifies, life gets tougher for all. 186 00:25:28,964 --> 00:25:32,604 Predators with permanent territories must tough it out, 187 00:25:33,364 --> 00:25:37,324 while most of their prey disappear over the horizon. 188 00:25:38,244 --> 00:25:40,044 (GRUNTING) 189 00:25:41,564 --> 00:25:47,124 To avoid starvation, many grassland animals follow a nomadic way of life. 190 00:25:49,484 --> 00:25:53,524 Over 2, 000, 000 wildebeests wander the East African savannahs 191 00:25:53,604 --> 00:25:55,284 chasing the rains. 192 00:26:08,924 --> 00:26:11,004 And they are not alone. 193 00:26:13,364 --> 00:26:14,844 Arriving on the wing, 194 00:26:14,924 --> 00:26:18,604 Jackson's Widowbirds also seek fresh grass. 195 00:26:18,844 --> 00:26:19,844 (CHIRPING) 196 00:26:20,644 --> 00:26:24,004 Although, it's not just food that they're after. 197 00:26:26,004 --> 00:26:27,004 (CHIRPS) 198 00:26:28,564 --> 00:26:30,644 This male wants a mate. 199 00:26:33,804 --> 00:26:36,804 He's grown elaborate breeding plumage for this moment, 200 00:26:38,844 --> 00:26:41,724 but he needs a stage on which to show it off. 201 00:26:46,084 --> 00:26:50,404 By carefully selecting grass blades, each trimmed to the correct length, 202 00:26:51,124 --> 00:26:53,284 he's creating something very special. 203 00:27:08,244 --> 00:27:10,804 He needs an even surface, 204 00:27:12,844 --> 00:27:14,164 and a centre-piece. 205 00:27:16,964 --> 00:27:18,324 The stage is set. 206 00:27:19,684 --> 00:27:24,164 His bachelor pad is sufficiently neat and tidy to attract a female. 207 00:27:26,004 --> 00:27:27,044 The problem is, 208 00:27:27,524 --> 00:27:28,684 can she see it? 209 00:27:28,764 --> 00:27:29,764 (CHIRPS) 210 00:27:32,724 --> 00:27:33,844 He has competition. 211 00:27:33,924 --> 00:27:35,284 (CHIRPING LOUDER) 212 00:27:44,204 --> 00:27:48,364 It might take more than a little gardening to impress the ladies. 213 00:27:50,804 --> 00:27:52,644 Jumping is the right idea, 214 00:27:54,004 --> 00:27:56,364 but he's misjudged the height of the grass. 215 00:28:06,284 --> 00:28:08,204 His rival makes it look easy. 216 00:28:31,444 --> 00:28:33,524 Time to raise his game. 217 00:28:38,484 --> 00:28:40,764 (BOTH CHIRPING) 218 00:29:09,124 --> 00:29:13,844 It's not only who jumps the highest, but who can keep doing so the longest. 219 00:29:22,924 --> 00:29:27,684 Unable to go the distance, his rivals drop out one by one. 220 00:29:32,324 --> 00:29:35,444 Stamina has won him admirers, 221 00:29:36,884 --> 00:29:40,044 now he can show off his courtship arena... 222 00:29:49,484 --> 00:29:53,124 And engage in a little romantic hide-and-seek. 223 00:30:05,044 --> 00:30:07,644 Finally, he's done enough. 224 00:30:19,364 --> 00:30:23,524 The East African savannahs support millions of grazers. 225 00:30:23,604 --> 00:30:24,604 (GRUNTING) 226 00:30:24,844 --> 00:30:28,324 Each year they devour millions of tons of grass, 227 00:30:30,484 --> 00:30:32,604 and yet there's one creature here 228 00:30:32,684 --> 00:30:37,564 whose impact is far greater than all these animals combined. 229 00:30:41,604 --> 00:30:44,564 They're found wherever grass grows on the planet, 230 00:30:45,324 --> 00:30:48,444 yet their labours go almost entirely unnoticed. 231 00:30:53,364 --> 00:30:58,844 One of the most remarkable is found here on the grasslands of South America. 232 00:31:01,804 --> 00:31:07,524 These blades are so tough that virtually no large grass eaters can stomach them. 233 00:31:08,764 --> 00:31:12,404 Yet they're harvested on an industrial scale... 234 00:31:13,044 --> 00:31:14,044 (CRACKING) 235 00:31:16,404 --> 00:31:19,044 ...by tiny grass cutter ants. 236 00:31:25,964 --> 00:31:28,724 But they themselves can't digest one bit of it. 237 00:31:31,964 --> 00:31:33,284 So, why bother? 238 00:31:37,644 --> 00:31:40,124 The answer is underground, 239 00:31:42,164 --> 00:31:44,204 and it's very ingenious. 240 00:31:48,884 --> 00:31:54,164 Each blade is cut to length and placed into a garden of fungus. 241 00:31:59,164 --> 00:32:05,564 The rotting grass feeds the fungus, and in turn the fungus feeds the ants. 242 00:32:09,164 --> 00:32:13,484 But feeding 5, 000, 000 workers requires intensive agriculture. 243 00:32:16,084 --> 00:32:19,324 Luckily, they are an industrious lot. 244 00:32:23,804 --> 00:32:28,724 This colony alone will collect over half a ton of grass every year. 245 00:32:32,924 --> 00:32:36,284 With billions of ant colonies across the world's grasslands 246 00:32:36,444 --> 00:32:41,844 all doing exactly the same thing, that's a mind-boggling amount of grass. 247 00:33:10,084 --> 00:33:14,004 It's estimated that over one third of the grass that grows on Earth 248 00:33:14,484 --> 00:33:17,124 will be harvested by an insect. 249 00:33:23,204 --> 00:33:29,044 In northern Australia, termites memorialise their industry in sculpture. 250 00:33:37,004 --> 00:33:40,044 These astonishing mounds are 10 feet tall. 251 00:33:40,804 --> 00:33:43,724 They're always built on a north-south axis, 252 00:33:43,804 --> 00:33:47,084 which is why their builders are called compass termites. 253 00:34:00,644 --> 00:34:02,364 These castles of clay 254 00:34:02,444 --> 00:34:05,164 protect their builders from extremes of heat 255 00:34:05,244 --> 00:34:09,084 and seasonal floods experienced on many grasslands. 256 00:34:20,604 --> 00:34:24,884 Termites manage to do what most grass eaters can't, 257 00:34:25,964 --> 00:34:29,284 break down dead grass and extract the nutrients. 258 00:34:30,644 --> 00:34:34,524 But they themselves can be food for those that can reach them. 259 00:34:35,284 --> 00:34:36,604 (SUCKING NOISE) 260 00:34:40,204 --> 00:34:41,964 A two-foot-long tongue 261 00:34:43,284 --> 00:34:45,404 covered in microscopic hooks, 262 00:34:48,804 --> 00:34:53,164 followed by claws longer than those of a velociraptor. 263 00:34:55,764 --> 00:34:56,764 (SNIFFING) 264 00:34:59,364 --> 00:35:02,804 A giant anteater on the plains of South America. 265 00:35:04,084 --> 00:35:05,084 (SLURPING) 266 00:35:07,764 --> 00:35:10,844 It can devour 20, 000 insects a day. 267 00:35:16,124 --> 00:35:21,364 Powerful forelegs enable it to rip apart a termite hill with ease. 268 00:35:31,364 --> 00:35:36,484 And as the sun bakes the grass, the termites face new danger. 269 00:35:45,044 --> 00:35:46,564 (FIRE CRACKLES) 270 00:35:58,564 --> 00:36:02,644 In minutes, fire turns grassland to ash. 271 00:36:16,524 --> 00:36:22,044 But the grasses are not dead. Their underground stems are unharmed. 272 00:36:25,324 --> 00:36:27,684 Weeks, months may pass, 273 00:36:28,124 --> 00:36:32,844 but eventually the rains will return and the grass will sprout again. 274 00:36:39,964 --> 00:36:45,164 Some grasslands must endure not only fire, but ice. 275 00:36:50,484 --> 00:36:55,164 As winter approaches, the prairies of North America begin to freeze. 276 00:36:56,444 --> 00:36:57,444 (CRACKING) 277 00:37:05,564 --> 00:37:07,124 (LOW GROWLING) 278 00:37:11,164 --> 00:37:13,684 In summer, bison roamed freely, 279 00:37:13,764 --> 00:37:17,244 almost continuously cropping the abundant green grass. 280 00:37:19,164 --> 00:37:24,364 Now, that grass is not only withered and frozen, it's about to be buried. 281 00:37:45,924 --> 00:37:50,604 Sixty million tons of snow now blanket this herd's territory. 282 00:37:52,564 --> 00:37:53,724 (SNORTING) 283 00:37:54,644 --> 00:37:57,884 Pushing through deep snow is exhausting work, 284 00:37:57,964 --> 00:38:00,564 and the bison are now slowly starving. 285 00:38:07,564 --> 00:38:10,844 Just keeping warm saps huge amounts of energy. 286 00:38:11,844 --> 00:38:13,764 (GROWLS) 287 00:38:17,364 --> 00:38:21,484 Their thick coats can insulate them down to minus 20 Fahrenheit. 288 00:38:22,404 --> 00:38:24,324 It's now minus 40. 289 00:38:27,324 --> 00:38:32,964 The only thing that will keep them alive is buried beneath three feet of snow. 290 00:38:37,604 --> 00:38:41,084 And that's a problem shared with a surprising neighbour. 291 00:38:58,964 --> 00:39:02,604 The food the fox seeks is also deep beneath the snow. 292 00:39:10,284 --> 00:39:11,724 (GRUNTING) 293 00:39:14,964 --> 00:39:19,604 The survival of both creatures depends on getting through to the ground. 294 00:39:25,084 --> 00:39:28,684 For the bison, it will be a matter of brute strength. 295 00:39:33,444 --> 00:39:38,124 Massive neck muscles enable them to shovel five tonnes of snow a day. 296 00:39:44,604 --> 00:39:47,524 Their light-weight neighbour needs more precision. 297 00:40:07,964 --> 00:40:08,964 (CHEWING) 298 00:40:15,124 --> 00:40:17,084 The bison have reached their goal, 299 00:40:17,884 --> 00:40:20,244 a mouthful of withered grass. 300 00:40:24,004 --> 00:40:28,604 And where the bison have dug, the fox now spots an opportunity. 301 00:40:37,564 --> 00:40:39,644 Every footstep counts, 302 00:40:42,604 --> 00:40:44,244 but he mustn't break through... 303 00:40:45,244 --> 00:40:46,244 Yet. 304 00:40:49,524 --> 00:40:52,924 He listens carefully to pinpoint his target. 305 00:40:57,524 --> 00:40:58,564 (PATTERING) 306 00:40:58,644 --> 00:40:59,644 It's moving. 307 00:41:17,804 --> 00:41:18,804 (SQUEAKS) 308 00:41:21,324 --> 00:41:22,324 A vole. 309 00:41:24,884 --> 00:41:30,244 Small, but 100 times more nutritious than a mouthful of dried grass. 310 00:41:36,964 --> 00:41:42,924 To get through the winter on these prairies, sometimes brain beats brawn. 311 00:41:49,644 --> 00:41:55,124 Ultimately, life on all grasslands depends on the turn of the seasons. 312 00:42:07,924 --> 00:42:08,924 (CRACKING) 313 00:42:20,764 --> 00:42:24,244 Five hundred miles further north than any tree can survive, 314 00:42:24,324 --> 00:42:26,924 grass returns to life. 315 00:42:35,724 --> 00:42:36,724 (CALLS) 316 00:42:37,724 --> 00:42:40,924 Caribou females have journeyed to the far north 317 00:42:41,684 --> 00:42:42,804 to calve. 318 00:42:43,284 --> 00:42:44,364 (CALLS) 319 00:42:46,644 --> 00:42:51,444 Over 70, 000 caribou babies will be born in the next few days. 320 00:42:56,284 --> 00:43:01,124 As the calves appear, so too do the leaves of the newly sprouting grass. 321 00:43:04,644 --> 00:43:06,644 And the calves must strengthen quickly. 322 00:43:07,044 --> 00:43:10,284 Within days they will have to keep up with their parents 323 00:43:10,404 --> 00:43:12,364 on a never-ending march. 324 00:43:17,364 --> 00:43:22,404 At one day old, they're already faster than an Olympic sprinter. 325 00:43:23,524 --> 00:43:27,524 They're testing the legs that will carry them thousands of miles, 326 00:43:29,044 --> 00:43:31,324 better to learn their limitations now. 327 00:43:39,444 --> 00:43:40,564 (CALLS) 328 00:43:45,724 --> 00:43:47,844 (CARIBOU GRUNTING) 329 00:43:51,244 --> 00:43:55,364 It may look playful, but there's no harder life on the grasslands 330 00:43:55,444 --> 00:43:58,084 than that facing these infants. 331 00:44:01,484 --> 00:44:03,724 The caribou mothers now join together, 332 00:44:03,804 --> 00:44:06,884 each with an infant exactly the same age. 333 00:44:15,444 --> 00:44:20,564 They're setting off on the greatest overland trek made by any animal. 334 00:44:43,724 --> 00:44:48,884 But wherever grass eaters travel, predators lie in wait. 335 00:44:50,604 --> 00:44:51,644 (CARIBOU CALLING) 336 00:44:55,684 --> 00:44:59,564 Here they are, Arctic wolves. 337 00:45:06,684 --> 00:45:08,284 They must seize their chance 338 00:45:08,364 --> 00:45:10,844 while the caribou pass through their territory. 339 00:45:43,964 --> 00:45:45,164 (PANTING) 340 00:45:46,964 --> 00:45:51,564 The wolf runs at the herd, trying to flush out the weak or the slow. 341 00:46:00,964 --> 00:46:02,644 A calf is separated. 342 00:46:11,004 --> 00:46:15,724 At full tilt, 40 miles an hour, the wolf is just faster. 343 00:46:24,044 --> 00:46:26,524 But the calf has stamina. 344 00:46:56,124 --> 00:47:01,524 Only a few weeks old, and this calf's will to survive is remarkable. 345 00:47:06,844 --> 00:47:08,684 And it needs to be, 346 00:47:09,124 --> 00:47:12,084 for these young caribou have now started a journey 347 00:47:12,364 --> 00:47:14,204 that will last a lifetime. 348 00:47:17,524 --> 00:47:22,324 Forever chasing the seasonal growth of the grass on which they depend. 349 00:47:31,404 --> 00:47:34,604 Like all grassland creatures, they are at the mercy 350 00:47:34,684 --> 00:47:39,124 of these unpredictable but ultimately bountiful lands. 351 00:47:45,244 --> 00:47:49,204 Grass can survive some of the harshest conditions on Earth, 352 00:47:49,284 --> 00:47:53,564 flood, fire and frost, and still flourish. 353 00:48:03,804 --> 00:48:07,204 So it is that grasslands provide a stage 354 00:48:07,484 --> 00:48:11,164 for the greatest gatherings of wildlife on planet Earth. 355 00:48:25,804 --> 00:48:29,524 For the grasslands team, no location would prove as challenging 356 00:48:29,644 --> 00:48:33,284 as that dominated by elephant grass in northeast India. 357 00:48:34,684 --> 00:48:39,724 The aim, to capture intimate images of some the world's most elusive creatures 358 00:48:40,164 --> 00:48:42,364 using the latest technology. 359 00:48:49,524 --> 00:48:51,444 But they will need to be careful. 360 00:48:53,884 --> 00:48:54,884 (COCKS GUN) 361 00:48:55,804 --> 00:48:56,804 (ELEPHANT TRUMPETS) 362 00:48:56,924 --> 00:49:00,124 More people are killed by wildlife here in Kaziranga 363 00:49:02,564 --> 00:49:05,524 than in any other national park on the planet. 364 00:49:07,604 --> 00:49:09,404 Every time we go into these tunnels, 365 00:49:10,084 --> 00:49:11,764 we have to take an armed guard, 366 00:49:12,404 --> 00:49:14,924 'cause there are so many animals in here that are dangerous. 367 00:49:15,004 --> 00:49:17,164 Tigers are probably the least of our worries, 368 00:49:17,484 --> 00:49:19,204 but rhinos and buffalo, 369 00:49:19,604 --> 00:49:22,004 elephants, sloth bear, all of them can injure you. 370 00:49:22,204 --> 00:49:24,284 And we gotta keep up with our armed guard. 371 00:49:30,284 --> 00:49:32,604 ATTENBOROUGH: The team have bumped into their first obstacle. 372 00:49:34,324 --> 00:49:35,804 SANDESH: There's a rhino right there. 373 00:49:39,004 --> 00:49:43,284 Let's go back because it's too risky going through this heavy grass. 374 00:49:45,684 --> 00:49:47,004 Let's get in the open. 375 00:49:48,404 --> 00:49:50,244 - (SPEAKING LOCAL LANGUAGE) - There's another rhino. 376 00:49:52,044 --> 00:49:54,244 - Now we have two rhinos. - Let's get in here. 377 00:49:56,604 --> 00:49:57,604 Okay. 378 00:49:58,324 --> 00:50:01,564 ATTENBOROUGH: The guard throws a ball of mud to one side of the rhinos, 379 00:50:01,804 --> 00:50:04,364 moving the animals on without harming them. 380 00:50:05,364 --> 00:50:06,684 (SHOUTS) 381 00:50:12,444 --> 00:50:14,444 - We're okay. It's gone. - Okay. 382 00:50:14,804 --> 00:50:16,124 What about the other one? 383 00:50:16,364 --> 00:50:17,524 Let's go, quick. 384 00:50:22,044 --> 00:50:24,604 ATTENBOROUGH: With the rhinos now a safe distance away, 385 00:50:24,684 --> 00:50:28,604 the crew focus on the best spots to position their camera traps. 386 00:50:29,124 --> 00:50:30,844 I love that tunnel, the effect. 387 00:50:34,964 --> 00:50:38,364 ATTENBOROUGH: Over 100 scaffold poles provide the anchor points 388 00:50:38,444 --> 00:50:40,324 for these secret cameras. 389 00:50:41,324 --> 00:50:43,684 When an animal triggers an infrared beam, 390 00:50:43,764 --> 00:50:47,004 the cameras will switch on automatically and start recording. 391 00:50:48,284 --> 00:50:52,844 If it works, the remote-control cameras should capture close-up footage 392 00:50:53,004 --> 00:50:56,324 without disturbing the animals or putting the crew at risk. 393 00:50:57,724 --> 00:51:00,804 Basically, that's about as much like grass as we can make it look. 394 00:51:00,884 --> 00:51:01,884 (CRICKETS CHIRP) 395 00:51:02,724 --> 00:51:06,124 ATTENBOROUGH: As night falls, the crew head back to base for safety. 396 00:51:08,244 --> 00:51:11,964 It's time for the new technology to prove its worth. 397 00:51:17,884 --> 00:51:22,484 At dawn, the crew have a whodunnit mystery on their hands. 398 00:51:22,684 --> 00:51:24,324 CHADDEN: Oh, wow. 399 00:51:25,124 --> 00:51:26,324 That's carnage! 400 00:51:27,724 --> 00:51:29,484 This looks like elephant, we think? 401 00:51:30,884 --> 00:51:32,724 This is scaffold pole 402 00:51:34,124 --> 00:51:36,604 they have bent. Look at that. (CHUCKLES) 403 00:51:39,964 --> 00:51:42,644 It's a sad day. You win some, you lose some. 404 00:51:43,204 --> 00:51:45,644 And this time, the animals have outsmarted us. 405 00:51:46,684 --> 00:51:48,804 In fact, check this out. (CHUCKLES) 406 00:51:49,324 --> 00:51:50,364 Whoo-hoo. 407 00:51:50,444 --> 00:51:55,084 So this is our little army of guards, protecting our trigger box. 408 00:51:55,684 --> 00:51:58,484 Do they bite? These ones, they bite? 409 00:51:59,044 --> 00:52:00,084 Sting? 410 00:52:00,164 --> 00:52:02,004 Whoa! Argh! Ow! 411 00:52:02,684 --> 00:52:04,804 The little (BLEEP). 412 00:52:08,404 --> 00:52:10,564 ATTENBOROUGH: While Chadden irons out the bugs, 413 00:52:11,524 --> 00:52:14,364 Sandesh has met some grumpy locals. 414 00:52:18,124 --> 00:52:21,684 Wild Asian water buffalo have extraordinary senses. 415 00:52:24,204 --> 00:52:26,724 Mothers will charge if they feel threatened. 416 00:52:29,604 --> 00:52:33,084 The guard carries a gun, in case a warning shot is needed, 417 00:52:33,244 --> 00:52:34,644 and with good reason. 418 00:52:37,404 --> 00:52:42,724 More people are killed by buffalo than by any other animal in Kaziranga. 419 00:52:44,364 --> 00:52:45,444 (GRUNTS) 420 00:52:48,204 --> 00:52:49,724 (SHOUTS) 421 00:52:49,804 --> 00:52:51,524 That'll wake you up in the morning. 422 00:52:52,244 --> 00:52:55,724 ATTENBOROUGH: Many of the park staff have cautionary tales about buffalo. 423 00:52:56,204 --> 00:52:59,124 (SPEAKING HINDI) 424 00:53:00,124 --> 00:53:03,684 The buffalo caught him here, through his throat 425 00:53:04,364 --> 00:53:07,244 and the horn came out through his mouth 426 00:53:07,764 --> 00:53:10,284 and flung him before running away. 427 00:53:10,364 --> 00:53:12,844 It's a miracle that he's still alive. 428 00:53:15,044 --> 00:53:17,564 ATTENBOROUGH: If the wildlife is unfriendly to humans, 429 00:53:18,804 --> 00:53:21,764 it's proving downright hostile to camera traps. 430 00:53:22,164 --> 00:53:25,484 CHADDEN: Completely ripped out the scaffold poles, 431 00:53:26,284 --> 00:53:29,284 they've torn the triggers. 432 00:53:30,484 --> 00:53:32,644 ATTENBOROUGH: While Chadden is convinced it's elephants, 433 00:53:32,724 --> 00:53:34,564 the rest of the crew are not so sure. 434 00:53:34,644 --> 00:53:36,044 SANDESH: This is huge! 435 00:53:36,684 --> 00:53:38,404 It's almost like a human footprint. 436 00:53:38,844 --> 00:53:41,844 You can see the front paw, the rear paw. 437 00:53:42,004 --> 00:53:46,364 CHADDEN: We are now two weeks in and it's very frustrating. 438 00:53:46,604 --> 00:53:49,204 I've never actually been anywhere where the animals 439 00:53:49,924 --> 00:53:52,604 go after your equipment and destroy it, more than here. 440 00:53:53,724 --> 00:53:56,884 ATTENBOROUGH: It's time for the team to do some detective work. 441 00:53:58,844 --> 00:54:01,684 Here is our little security camera. 442 00:54:01,764 --> 00:54:04,964 If any animals are coming through and vandalising our main cameras, 443 00:54:05,684 --> 00:54:09,124 we hope that they're being caught on these little things. 444 00:54:12,164 --> 00:54:14,604 ATTENBOROUGH: As the crew up their spying efforts, 445 00:54:14,684 --> 00:54:17,084 the guards take them to a promising lead. 446 00:54:18,124 --> 00:54:21,324 Nothing attracts tigers like a rhino carcass. 447 00:54:22,004 --> 00:54:24,924 It's very fresh. It's like from the morning. 448 00:54:25,284 --> 00:54:27,164 And it looks like there's a tiger cub, 449 00:54:28,164 --> 00:54:33,004 so it should be a tigress with cubs, coming to feed on this rhino carcass. 450 00:54:33,284 --> 00:54:34,364 It's pretty cool. 451 00:54:35,804 --> 00:54:39,444 ATTENBOROUGH: Chadden decides to give the camera traps one last chance. 452 00:54:40,124 --> 00:54:44,884 If there are tigers around, they might scare away the mystery vandals. 453 00:54:46,404 --> 00:54:47,684 Elsewhere in the park, 454 00:54:47,764 --> 00:54:51,404 the security cameras are turning up some unexpected results. 455 00:54:51,884 --> 00:54:55,444 At nighttime, survived another... Ooh! 456 00:54:56,124 --> 00:54:57,244 It's a bear. 457 00:54:58,244 --> 00:54:59,964 Wow, that's a very rare sighting. 458 00:55:00,124 --> 00:55:01,804 SANDESH: I've never seen a bear in Kaziranga. 459 00:55:01,884 --> 00:55:03,444 In all my years, never. 460 00:55:04,844 --> 00:55:08,684 - Oh, his fingernails... - Look at his claws, right on the lens. 461 00:55:09,684 --> 00:55:11,844 CHADDEN: So I thought this was elephant damage. 462 00:55:12,844 --> 00:55:15,924 I never thought we'd see a sloth bear doing that. 463 00:55:16,764 --> 00:55:17,804 That's amazing. 464 00:55:21,884 --> 00:55:26,124 ATTENBOROUGH: A return to the rhino carcass and the plot thickens. 465 00:55:27,484 --> 00:55:28,804 SANDESH: Our transmitter's gone. 466 00:55:29,684 --> 00:55:31,044 CHADDEN: That's what tigers think of camera traps. 467 00:55:31,124 --> 00:55:33,044 CREW MEMBER: Do you think there's a bit over there? 468 00:55:33,204 --> 00:55:34,204 Pieces. 469 00:55:34,644 --> 00:55:38,164 ATTENBOROUGH: The security cameras have caught a new culprit. 470 00:55:38,284 --> 00:55:40,164 CHADDEN: Oh, my goodness, there they are. 471 00:55:40,244 --> 00:55:41,244 SANDESH: Ooh! 472 00:55:41,364 --> 00:55:43,644 There it's a tigress, see that. It's a tigress. 473 00:55:43,724 --> 00:55:45,924 It snarled at the camera trap, look at that. 474 00:55:46,004 --> 00:55:47,524 Sure don't like camera traps. 475 00:55:48,284 --> 00:55:49,284 Okay. 476 00:55:50,684 --> 00:55:52,804 ATTENBOROUGH: With the technology struggling, 477 00:55:52,884 --> 00:55:56,484 Sandesh decides to put himself on the frontline. 478 00:55:56,564 --> 00:55:58,324 CHADDEN: It's on. SANDESH: And now we're ready. 479 00:55:59,204 --> 00:56:00,524 Time to get the tiger. 480 00:56:02,164 --> 00:56:05,684 ATTENBOROUGH: He'll have no protection apart from a thin wall of grass, 481 00:56:06,004 --> 00:56:09,684 and must hope he's as well-hidden as the local wildlife. 482 00:56:11,884 --> 00:56:15,124 Over the next five days, Sandesh plays the role 483 00:56:15,204 --> 00:56:16,844 of human camera trap. 484 00:56:18,724 --> 00:56:19,844 (BIRDS CAWING) 485 00:56:19,924 --> 00:56:23,804 Eventually, the more hands-on approach pays off. 486 00:56:50,164 --> 00:56:53,364 Traditional filming methods and a little bit of patience, 487 00:56:53,564 --> 00:56:57,364 have helped reveal the hidden creatures of Kaziranga. 488 00:57:02,284 --> 00:57:03,284 (GRUNTS) 489 00:57:03,404 --> 00:57:06,364 But it's good to know there are still wild places 490 00:57:06,484 --> 00:57:09,524 where animals like to keep their secrets. 491 00:57:13,204 --> 00:57:14,484 (CREAKING) 492 00:57:15,804 --> 00:57:17,164 CHADDEN: I knew it was elephants. 493 00:57:20,204 --> 00:57:21,324 ATTENBOROUGH: Next time, 494 00:57:22,684 --> 00:57:25,404 we venture to the newest habitat on Earth, 495 00:57:26,084 --> 00:57:27,604 our cities. 496 00:57:28,404 --> 00:57:31,284 To reveal the extraordinary ways 497 00:57:32,004 --> 00:57:35,324 that animals survive in this man-made world. 498 00:57:40,204 --> 00:57:42,204 (THEME MUSIC PLAYING)