1 00:00:34,500 --> 00:00:38,660 One quarter of all the land on Earth is covered by a single, 2 00:00:38,660 --> 00:00:40,540 remarkable type of plant. 3 00:00:47,300 --> 00:00:51,220 Almost indestructible, it can grow two feet in a day... 4 00:00:58,060 --> 00:01:01,780 ..and be tall enough to hide a giant. 5 00:01:01,780 --> 00:01:04,060 LOW RUMBLING 6 00:01:05,780 --> 00:01:10,780 That plant is grass, and the world it creates is truly unique. 7 00:01:24,940 --> 00:01:28,620 The grass in northern India is the tallest on the planet, 8 00:01:28,620 --> 00:01:32,580 home to some of the most impressive creatures to tread the Earth. 9 00:01:35,500 --> 00:01:38,980 GRUNTING 10 00:01:47,900 --> 00:01:51,420 These are the good times, but in just a few months, 11 00:01:51,420 --> 00:01:54,140 all this fresh growth will be gone 12 00:01:54,140 --> 00:01:57,100 and the animals will be forced to move on. 13 00:02:00,100 --> 00:02:04,420 That is the way things are on grasslands across the planet. 14 00:02:04,420 --> 00:02:07,180 BIRDS TWEET 15 00:02:08,380 --> 00:02:12,660 A cycle of abundance, destruction and rebirth 16 00:02:12,660 --> 00:02:15,100 that affects every creature that lives here. 17 00:02:22,220 --> 00:02:25,580 LOW RUMBLING 18 00:02:30,420 --> 00:02:34,980 The largest grassland on Earth, the vast Eurasian Steppe, 19 00:02:34,980 --> 00:02:43,020 stretches one third of the way around our planet. 20 00:02:43,020 --> 00:02:47,820 Spring rain has brought fresh grass and, with it, new life. 21 00:02:52,140 --> 00:02:54,700 A relic from the ice age, 22 00:02:54,700 --> 00:02:57,060 a baby saiga antelope, 23 00:02:57,060 --> 00:02:58,540 just three hours old. 24 00:03:02,220 --> 00:03:04,500 His only company, his twin. 25 00:03:06,020 --> 00:03:10,300 Until they can stand, their mother has left them hidden in the grass. 26 00:03:18,340 --> 00:03:21,340 They should be safe, as long as they remain quiet. 27 00:03:23,780 --> 00:03:24,780 HE BLEATS 28 00:03:27,060 --> 00:03:29,780 For these calves, the clock is already ticking. 29 00:03:31,380 --> 00:03:36,020 Their herd will soon be moving on, seeking the freshest, new grass. 30 00:03:36,020 --> 00:03:38,380 BLEATING 31 00:03:39,620 --> 00:03:40,780 HE BLEATS 32 00:03:48,300 --> 00:03:49,900 HE BLEATS 33 00:03:53,340 --> 00:03:56,460 Their lanky legs are a sure sign that they're built for a life 34 00:03:56,460 --> 00:03:58,180 on the move. 35 00:04:04,740 --> 00:04:06,620 HE BLEATS 36 00:04:09,180 --> 00:04:11,300 BLEATING 37 00:04:22,140 --> 00:04:24,340 Saiga always give birth to twins, 38 00:04:24,340 --> 00:04:26,380 so their numbers grow rapidly 39 00:04:26,380 --> 00:04:28,420 just when grass is plentiful. 40 00:04:32,500 --> 00:04:35,780 Their bizarrely shaped nose can detect fresh growth 41 00:04:35,780 --> 00:04:37,780 from hundreds of miles away. 42 00:04:41,900 --> 00:04:45,580 BLEATING 43 00:04:49,740 --> 00:04:53,940 The young twins will now begin the nomadic life they share with 44 00:04:53,940 --> 00:04:56,780 most animals on the world's open plains. 45 00:05:18,340 --> 00:05:21,260 Grasslands occur where rain is too 46 00:05:21,260 --> 00:05:23,980 sporadic for forests to exist. 47 00:05:23,980 --> 00:05:26,740 THUNDER RUMBLES 48 00:05:26,740 --> 00:05:30,340 WIND WHOOSHES 49 00:05:34,100 --> 00:05:37,540 The rain that a grassland needs to survive for a year 50 00:05:37,540 --> 00:05:39,460 might arrive all at once. 51 00:05:43,700 --> 00:05:48,140 CRASHING AND RUMBLING 52 00:06:00,380 --> 00:06:02,820 Storms like these can release 53 00:06:02,820 --> 00:06:05,060 12 inches of rain in 24 hours. 54 00:06:15,860 --> 00:06:18,540 Not much fun if you're out in it. 55 00:06:30,460 --> 00:06:34,860 Eventually, the Earth can't soak up any more... 56 00:06:34,860 --> 00:06:36,140 RUMBLING 57 00:06:36,140 --> 00:06:39,740 ..and the grassland undergoes a radical change. 58 00:06:46,900 --> 00:06:51,220 Many plants would drown here, but grasses thrive. 59 00:06:54,340 --> 00:06:55,740 They grow so fast, 60 00:06:55,740 --> 00:06:59,420 their leaves quickly rise above the water and into the sunlight. 61 00:07:02,020 --> 00:07:03,540 BIRDS TWEET 62 00:07:03,540 --> 00:07:05,580 Here in southern Africa, 63 00:07:05,580 --> 00:07:12,260 water transforms one of the most remarkable grasslands on Earth. 64 00:07:12,260 --> 00:07:13,540 The Okavango. 65 00:07:17,340 --> 00:07:21,540 Every year, 5,000 square miles of grassland are flooded. 66 00:07:29,740 --> 00:07:33,620 For one pride of lions, this poses a major problem. 67 00:07:36,180 --> 00:07:39,780 There may be plenty of prey around, but lions struggle 68 00:07:39,780 --> 00:07:41,020 to run it down in water. 69 00:07:53,620 --> 00:07:55,660 CUBS MEOW 70 00:07:56,980 --> 00:07:59,740 If their mothers don't make a kill soon, 71 00:07:59,740 --> 00:08:01,780 the cubs might not survive the week. 72 00:08:11,740 --> 00:08:13,420 But fuelled by the flood, 73 00:08:13,420 --> 00:08:17,420 the eruption of grass attracts new possible prey. 74 00:08:20,460 --> 00:08:23,060 Buffalo arrive in herds 2,000 strong. 75 00:08:30,940 --> 00:08:34,580 Powerful, aggressive and united, 76 00:08:34,580 --> 00:08:37,340 they're the most dangerous animal a lion can face. 77 00:09:01,580 --> 00:09:03,220 HE GRUNTS 78 00:09:14,620 --> 00:09:16,420 The biggest bulls don't run. 79 00:09:19,140 --> 00:09:22,380 They're simply too huge to be scared of lions. 80 00:09:24,980 --> 00:09:29,740 At 900 kilos, he weighs more than all five lionesses combined. 81 00:09:34,380 --> 00:09:36,540 The pride do have numbers on their side... 82 00:09:38,020 --> 00:09:40,620 ..but one sweep of his horns could be deadly. 83 00:09:54,780 --> 00:09:56,460 One distracts the bull up front, 84 00:09:56,460 --> 00:09:58,620 while her sisters attack from behind. 85 00:10:10,100 --> 00:10:13,860 The cats must somehow topple the buffalo, but with swamp underfoot, 86 00:10:13,860 --> 00:10:15,500 they can't get any traction. 87 00:10:15,500 --> 00:10:16,700 LIONS ROAR 88 00:10:58,580 --> 00:10:59,980 The bull is weakening... 89 00:11:01,180 --> 00:11:03,220 ..but the lions are tiring too. 90 00:11:08,420 --> 00:11:11,700 It's now a battle of will as much as strength. 91 00:11:15,100 --> 00:11:18,580 To live, the bull must somehow shake off the lioness. 92 00:11:56,500 --> 00:12:00,260 The bull is wounded, but thanks to his two-inch-thick hide, 93 00:12:00,260 --> 00:12:01,420 he will recover. 94 00:12:07,740 --> 00:12:11,260 For the pride, these are hungry times. 95 00:12:11,260 --> 00:12:13,220 CUB SQUEAKS 96 00:12:19,180 --> 00:12:22,780 But ultimately, once the water recedes, 97 00:12:22,780 --> 00:12:26,860 there will be new life and new food to benefit all. 98 00:12:35,940 --> 00:12:37,620 In the right conditions, 99 00:12:37,620 --> 00:12:40,780 grasses have the extraordinary ability to grow from 100 00:12:40,780 --> 00:12:44,260 first shoots to flower in a matter of only days. 101 00:12:51,740 --> 00:12:55,700 Grasses become the miniature equivalents of fruiting trees. 102 00:13:03,140 --> 00:13:05,700 And, for creatures living within the grass, 103 00:13:05,700 --> 00:13:09,820 this is a landscape as vast and towering as any rainforest. 104 00:13:15,340 --> 00:13:18,060 An excellent place to build a tiny treehouse... 105 00:13:20,260 --> 00:13:21,860 ..for a harvest mouse. 106 00:13:33,740 --> 00:13:37,660 During summer, European meadowlands are full of food... 107 00:13:40,900 --> 00:13:42,940 ..but only for those that can reach it. 108 00:14:02,020 --> 00:14:05,020 Climbing grass is harder than climbing trees, 109 00:14:05,020 --> 00:14:07,980 not least because their stems just won't stay still. 110 00:14:16,060 --> 00:14:19,140 A prehensile tail acts like a fifth limb, 111 00:14:19,260 --> 00:14:19,340 A prehensile tail acts like a fifth limb, 112 00:14:19,340 --> 00:14:23,300 so she's as agile as a monkey clambering around in a tree. 113 00:14:25,540 --> 00:14:27,380 STEM 'CREAKS' 114 00:14:31,540 --> 00:14:35,100 And just as well, for the best food in this tiny forest 115 00:14:35,100 --> 00:14:37,220 is at the very top of its canopy. 116 00:14:47,900 --> 00:14:50,700 Feeding up here, she's exposed. 117 00:14:57,860 --> 00:14:59,100 A barn owl. 118 00:15:30,260 --> 00:15:31,820 Not her finest move... 119 00:15:35,620 --> 00:15:36,940 ..but it did the trick. 120 00:15:39,420 --> 00:15:42,700 Harvest mice seldom go all the way down to the ground. 121 00:15:46,260 --> 00:15:49,260 It's a tangled and dangerous world down here. 122 00:16:02,580 --> 00:16:07,740 But she can read the pattern of the stems overhead like a map, 123 00:16:07,740 --> 00:16:09,620 and so find her way home. 124 00:16:17,700 --> 00:16:19,980 And not a minute too soon. 125 00:16:24,740 --> 00:16:26,860 There are mouths to feed. 126 00:16:40,020 --> 00:16:42,460 Her babies must fatten up quickly. 127 00:16:44,900 --> 00:16:47,420 They need to harvest the summer grasses 128 00:16:47,420 --> 00:16:49,460 while they're still rich with food. 129 00:16:57,660 --> 00:17:01,140 On the African savanna, too, seasonal grasses 130 00:17:01,140 --> 00:17:02,980 are filled with life, 131 00:17:02,980 --> 00:17:04,980 but it won't last long. 132 00:17:08,340 --> 00:17:11,300 Carmine bee-eaters are superb aerial hunters... 133 00:17:13,100 --> 00:17:16,180 ..experts at catching insects in mid-air. 134 00:17:23,940 --> 00:17:27,060 But they have no way of flushing their prey out of the grass. 135 00:17:35,380 --> 00:17:37,380 INSECTS HUM AND CLICK 136 00:17:37,380 --> 00:17:40,700 Once alarmed, most insects stay put. 137 00:17:43,820 --> 00:17:47,380 The bee-eaters need someone to stir things up a bit. 138 00:17:53,260 --> 00:17:54,620 A kori bustard. 139 00:17:59,580 --> 00:18:02,100 It's the world's heaviest flying bird, 140 00:18:02,100 --> 00:18:04,940 so it should be bulky enough to kick up some insects. 141 00:18:11,020 --> 00:18:12,660 BUZZING 142 00:18:12,660 --> 00:18:13,820 Bingo! 143 00:18:16,660 --> 00:18:18,700 Until someone else comes along... 144 00:18:20,140 --> 00:18:21,660 ..and cramps your style. 145 00:18:27,500 --> 00:18:29,420 Never mind. 146 00:18:29,420 --> 00:18:32,060 Perhaps there are bigger opportunities ahead. 147 00:18:34,700 --> 00:18:36,340 What about an ostrich? 148 00:18:39,060 --> 00:18:40,780 The heaviest bird of all. 149 00:18:46,300 --> 00:18:49,820 This time, there's more than enough transport to go around. 150 00:18:59,860 --> 00:19:03,700 Soon, almost every ostrich has its own passenger. 151 00:19:11,420 --> 00:19:15,340 But free riders are only tolerated for so long. 152 00:19:22,260 --> 00:19:25,620 What the bee-eaters really need is a creature so big, 153 00:19:25,620 --> 00:19:27,220 it won't even notice them. 154 00:19:29,140 --> 00:19:30,740 SNORTING 155 00:19:31,660 --> 00:19:34,420 LOW RUMBLING 156 00:19:37,580 --> 00:19:42,620 Nothing cuts a swathe through grass like an African bull elephant. 157 00:19:53,140 --> 00:19:55,380 ELEPHANT GROWLS 158 00:19:59,060 --> 00:20:03,740 The trick is to fly as close to the front of the giant as possible. 159 00:20:03,740 --> 00:20:06,420 They only have a split second to grab the prize. 160 00:20:16,660 --> 00:20:20,940 As more insects are stirred up, the competition intensifies. 161 00:20:22,460 --> 00:20:24,740 BIRDS CHIRP 162 00:20:42,660 --> 00:20:46,580 With summer drawing to a close, the race to stock up is on. 163 00:20:52,220 --> 00:20:57,100 Soon the grass will wither, and this opportunity will have gone. 164 00:21:07,140 --> 00:21:09,420 As the dry season takes hold, 165 00:21:09,420 --> 00:21:12,500 food becomes increasingly thin on the ground. 166 00:21:14,860 --> 00:21:17,740 Now, only the most specialised predators on the plains 167 00:21:17,740 --> 00:21:19,180 can make a living. 168 00:21:25,220 --> 00:21:29,780 She may be spotted like a cheetah, but this cat is no sprinter. 169 00:21:42,740 --> 00:21:48,060 Instead, she has extra long legs, which give her a high vantage point. 170 00:21:58,620 --> 00:22:01,620 But a serval cat's main weapon 171 00:22:01,620 --> 00:22:04,180 are enormous radar ears. 172 00:22:04,180 --> 00:22:06,660 RUSTLING 173 00:22:08,460 --> 00:22:11,300 They help her pinpoint prey hiding in the grass. 174 00:22:20,260 --> 00:22:22,940 But the prey she seeks are canny. 175 00:22:26,940 --> 00:22:28,380 Southern vlei rats. 176 00:22:31,620 --> 00:22:34,740 They know that any sustained movement can give them away. 177 00:22:40,620 --> 00:22:43,020 So they move in short bursts. 178 00:22:50,940 --> 00:22:54,980 But even the slightest rustle will give her a clue. 179 00:23:16,740 --> 00:23:17,860 Warm. 180 00:23:30,140 --> 00:23:31,420 Warmer. 181 00:23:45,540 --> 00:23:46,980 Missed. 182 00:23:48,620 --> 00:23:50,460 RUSTLING 183 00:24:20,580 --> 00:24:22,220 RUSTLING 184 00:24:24,100 --> 00:24:25,420 RUSTLING 185 00:24:32,820 --> 00:24:38,620 BIRD TWEETS 186 00:25:00,580 --> 00:25:02,260 SQUEAKING 187 00:25:05,900 --> 00:25:08,980 In better times, she could catch ten a day. 188 00:25:10,300 --> 00:25:14,740 But now, with so few rodents around, she will have to go hungry. 189 00:25:17,300 --> 00:25:19,620 As drought intensifies, 190 00:25:19,620 --> 00:25:22,060 life gets tougher for all. 191 00:25:28,580 --> 00:25:33,060 Predators with permanent territories must tough it out, 192 00:25:33,060 --> 00:25:36,900 while most of their prey disappear over the horizon. 193 00:25:36,900 --> 00:25:39,820 GRUNTING AND MOOING 194 00:25:41,020 --> 00:25:44,780 To avoid starvation, many grassland animals follow 195 00:25:44,780 --> 00:25:46,300 a nomadic way of life. 196 00:25:49,140 --> 00:25:52,500 Over two million wildebeest wander the East African savannas, 197 00:25:52,500 --> 00:25:54,300 chasing the rains. 198 00:26:08,380 --> 00:26:10,060 And they are not alone. 199 00:26:12,860 --> 00:26:17,780 Arriving on the wing, Jackson's widowbirds also seek fresh grass. 200 00:26:20,260 --> 00:26:23,380 Although, it's not just food that they're after. 201 00:26:27,740 --> 00:26:30,020 This male wants a mate. 202 00:26:33,380 --> 00:26:36,540 He's grown elaborate breeding plumage for this moment. 203 00:26:38,260 --> 00:26:41,140 But he needs a stage on which to show it off. 204 00:26:45,620 --> 00:26:50,660 By carefully selecting grass blades, each trimmed to the correct length, 205 00:26:50,660 --> 00:26:52,820 he's creating something very special. 206 00:27:07,580 --> 00:27:09,980 He needs an even surface... 207 00:27:12,140 --> 00:27:13,380 ..and a centrepiece. 208 00:27:16,380 --> 00:27:17,820 The stage is set. 209 00:27:25,340 --> 00:27:27,860 The problem is, can she see it? 210 00:27:27,860 --> 00:27:30,420 BIRDS TWEET 211 00:27:31,940 --> 00:27:33,620 He has competition. 212 00:27:33,620 --> 00:27:34,580 TWEETING 213 00:27:36,340 --> 00:27:40,180 TWEETING 214 00:27:43,420 --> 00:27:47,900 It might take more than a little gardening to impress the ladies. 215 00:27:50,060 --> 00:27:51,900 Jumping is the right idea... 216 00:27:53,420 --> 00:27:56,020 ..but he's misjudged the height of the grass. 217 00:27:56,020 --> 00:28:00,020 TWEETING 218 00:28:05,660 --> 00:28:07,820 His rival makes it look easy. 219 00:28:07,820 --> 00:28:09,500 TWEETING 220 00:28:14,580 --> 00:28:15,740 TWEETING 221 00:28:20,220 --> 00:28:23,260 TWEETING 222 00:28:25,660 --> 00:28:27,540 TWEETING 223 00:28:30,780 --> 00:28:32,580 Time to raise his game. 224 00:28:33,940 --> 00:28:36,660 TWEETING 225 00:29:08,540 --> 00:29:10,780 It's not only who jumps the highest, 226 00:29:10,780 --> 00:29:12,820 but who can keep doing so the longest. 227 00:29:22,180 --> 00:29:26,620 Unable to go the distance, his rivals drop out one by one. 228 00:29:31,740 --> 00:29:34,660 Stamina has won him admirers. 229 00:29:36,380 --> 00:29:39,300 Now he can show off his courtship arena. 230 00:29:49,060 --> 00:29:52,220 And engage in a little romantic hide-and-seek. 231 00:30:04,300 --> 00:30:06,980 Finally, he's done enough. 232 00:30:18,460 --> 00:30:22,620 The East African savannas support millions of grazers. 233 00:30:24,060 --> 00:30:27,820 Each year, they devour millions of tonnes of grass. 234 00:30:29,980 --> 00:30:33,940 And yet, there's one creature here whose impact is far greater 235 00:30:33,940 --> 00:30:40,860 than all these animals combined. 236 00:30:40,860 --> 00:30:44,660 They're found wherever grass grows on the planet. 237 00:30:44,660 --> 00:30:48,300 Yet their labours go almost entirely unnoticed. 238 00:30:52,540 --> 00:30:55,420 One of the most remarkable is found here, 239 00:30:55,420 --> 00:30:58,660 on the grasslands of South America. 240 00:31:01,020 --> 00:31:03,260 These blades are so tough 241 00:31:03,260 --> 00:31:06,900 that virtually no large grass eaters can stomach them. 242 00:31:08,020 --> 00:31:12,460 Yet, they are harvested on an industrial scale... 243 00:31:16,020 --> 00:31:18,820 ..by tiny grass-cutter ants. 244 00:31:25,780 --> 00:31:28,580 But they themselves can't digest one bit of it. 245 00:31:30,740 --> 00:31:32,980 So, why bother? 246 00:31:36,420 --> 00:31:39,620 The answer is underground. 247 00:31:41,460 --> 00:31:43,820 And it's very ingenious. 248 00:31:47,980 --> 00:31:54,220 Each blade is cut to length and placed into a garden of fungus. 249 00:31:58,420 --> 00:32:01,220 The rotting grass feeds the fungus 250 00:32:01,220 --> 00:32:05,460 and, in turn, the fungus feeds the ants. 251 00:32:08,020 --> 00:32:13,380 But feeding five million workers requires intensive agriculture. 252 00:32:15,660 --> 00:32:19,100 Luckily, they are an industrious lot. 253 00:32:23,380 --> 00:32:31,940 This colony alone will collect over half a tonne of grass every year. 254 00:32:31,940 --> 00:32:35,820 With billions of ant colonies across the world's grasslands 255 00:32:35,820 --> 00:32:38,500 all doing exactly the same thing, 256 00:32:38,500 --> 00:32:41,380 that's a mind-boggling amount of grass. 257 00:33:13,740 --> 00:33:16,820 will be harvested by an insect. 258 00:33:22,460 --> 00:33:24,300 In northern Australia, 259 00:33:24,300 --> 00:33:28,780 termites memorialise their industry in sculpture. 260 00:33:35,500 --> 00:33:39,940 These astonishing mounds are ten feet tall. 261 00:33:39,940 --> 00:33:43,140 They're always built on a north-south axis 262 00:33:43,140 --> 00:33:47,580 which is why their builders are called compass termites. 263 00:33:59,980 --> 00:34:04,500 These castles of clay protect their builders from extremes of heat 264 00:34:04,500 --> 00:34:08,540 and seasonal floods experienced on many grasslands. 265 00:34:19,660 --> 00:34:24,860 Termites manage to do what most grass eaters can't - 266 00:34:24,860 --> 00:34:29,140 break down dead grass and extract the nutrients. 267 00:34:29,140 --> 00:34:34,180 But they themselves can be food for those that can reach them. 268 00:34:39,540 --> 00:34:41,340 A two-foot-long tongue... 269 00:34:42,700 --> 00:34:45,180 ..covered in microscopic hooks... 270 00:34:48,700 --> 00:34:53,460 ..followed by claws longer than those of a velociraptor. 271 00:34:58,260 --> 00:35:02,700 A giant anteater on the plains of South America. 272 00:35:07,260 --> 00:35:10,140 It can devour 20,000 insects a day. 273 00:35:15,220 --> 00:35:20,860 Powerful forelegs enable it to rip apart a termite hill with ease. 274 00:35:30,660 --> 00:35:36,220 And, as the sun bakes the grass, the termites face new danger. 275 00:35:57,860 --> 00:36:07,140 In minutes, fire turns grassland to ash. 276 00:36:15,980 --> 00:36:18,620 But the grasses are not dead. 277 00:36:18,620 --> 00:36:22,060 Their underground stems are unharmed. 278 00:36:24,260 --> 00:36:27,500 Weeks, months may pass 279 00:36:27,500 --> 00:36:30,140 but, eventually, the rains will return 280 00:36:30,140 --> 00:36:32,580 and the grass will sprout again. 281 00:36:39,580 --> 00:36:54,940 Some grasslands must endure not only fire, but ice. 282 00:37:04,660 --> 00:37:05,660 BISON GROWLS 283 00:37:10,700 --> 00:37:13,140 In summer, bison roamed freely, 284 00:37:13,140 --> 00:37:16,860 almost continuously cropping the abundant green grass. 285 00:37:18,580 --> 00:37:24,300 Now that grass is not only withered and frozen, it's about to be buried. 286 00:37:34,140 --> 00:37:36,740 GRUNTING 287 00:37:45,300 --> 00:37:50,620 60 million tonnes of snow now blanket this herd's territory. 288 00:37:53,900 --> 00:37:57,180 Pushing through deep snow is exhausting work 289 00:37:57,180 --> 00:38:00,700 and the bison are now slowly starving. 290 00:38:07,060 --> 00:38:11,500 Just keeping warm saps huge amounts of energy. 291 00:38:11,500 --> 00:38:13,340 GROWLING 292 00:38:16,380 --> 00:38:21,380 Their thick coats can insulate them down to minus 20 Fahrenheit. 293 00:38:21,380 --> 00:38:24,100 It's now minus 40. 294 00:38:26,740 --> 00:38:29,740 The only thing that will keep them alive 295 00:38:29,740 --> 00:38:32,460 is buried beneath three feet of snow. 296 00:38:37,140 --> 00:38:40,940 And that's a problem shared with a surprising neighbour. 297 00:38:58,660 --> 00:39:02,300 The food the fox seeks is also deep beneath the snow. 298 00:39:09,380 --> 00:39:11,180 GROWLING 299 00:39:13,780 --> 00:39:16,300 The survival of both creatures 300 00:39:16,300 --> 00:39:19,700 depends on getting through to the ground. 301 00:39:24,780 --> 00:39:28,340 For the bison, it will be a matter of brute strength. 302 00:39:32,740 --> 00:39:38,220 Massive neck muscles enable them to shovel five tonnes of snow a day. 303 00:39:43,900 --> 00:39:47,380 Their lightweight neighbour needs more precision. 304 00:40:07,300 --> 00:40:08,740 BISON GROWLS 305 00:40:14,380 --> 00:40:17,140 The bison have reached their goal. 306 00:40:17,140 --> 00:40:19,940 A mouthful of withered grass. 307 00:40:23,940 --> 00:40:29,100 And where the bison have dug, the fox now spots an opportunity. 308 00:40:36,420 --> 00:40:39,180 Every footstep counts. 309 00:40:41,820 --> 00:40:44,060 But he mustn't break through... 310 00:40:44,060 --> 00:40:45,660 yet. 311 00:40:48,820 --> 00:40:52,580 He listens carefully to pinpoint his target. 312 00:40:57,820 --> 00:40:59,220 It's moving. 313 00:41:20,540 --> 00:41:22,060 A vole. 314 00:41:24,300 --> 00:41:27,340 Small, but 100 times more nutritious 315 00:41:27,340 --> 00:41:30,420 than a mouthful of dried grass. 316 00:41:36,300 --> 00:41:38,900 To get through the winter on these prairies, 317 00:41:38,900 --> 00:41:42,860 sometimes brain beats brawn. 318 00:41:48,860 --> 00:41:54,940 Ultimately, life on all grasslands depends on the turn of the seasons. 319 00:42:20,100 --> 00:42:24,100 500 miles further north than any tree can survive, 320 00:42:24,100 --> 00:42:26,700 grass returns to life. 321 00:42:36,220 --> 00:42:42,460 Caribou females have journeyed to the far north to calve. 322 00:42:45,740 --> 00:42:51,500 Over 70,000 caribou babies will be born in the next few days. 323 00:42:55,060 --> 00:43:00,980 As the calves appear, so too do the leaves of the newly-sprouting grass. 324 00:43:03,180 --> 00:43:06,380 And the calves must strengthen quickly. 325 00:43:06,380 --> 00:43:09,580 Within days, they will have to keep up with their parents 326 00:43:09,580 --> 00:43:12,140 on a never-ending march. 327 00:43:17,260 --> 00:43:23,100 At one-day-old, they are already faster than an Olympic sprinter. 328 00:43:23,100 --> 00:43:26,740 They are testing the legs that will carry them thousands of miles. 329 00:43:28,260 --> 00:43:31,140 Better to learn their limitations now. 330 00:43:38,660 --> 00:43:40,500 CALF HONKS 331 00:43:50,740 --> 00:43:54,860 It may look playful, but there's no harder life on the grasslands 332 00:43:54,860 --> 00:43:57,580 than that facing these infants. 333 00:44:00,620 --> 00:44:03,260 The caribou mothers now join together, 334 00:44:03,260 --> 00:44:06,740 each with an infant exactly the same age. 335 00:44:14,860 --> 00:44:20,220 They're setting off on the greatest overland trek made by any animal. 336 00:44:43,100 --> 00:44:49,300 But wherever grass eaters travel, predators lie in wait. 337 00:44:54,700 --> 00:44:57,180 Here they are. 338 00:44:57,180 --> 00:44:59,260 Arctic wolves. 339 00:45:05,940 --> 00:45:07,580 They must seize their chance 340 00:45:07,580 --> 00:45:10,740 while the caribou pass through their territory. 341 00:45:29,620 --> 00:45:31,980 CARIBOU GRUNTS 342 00:45:46,140 --> 00:45:51,060 The wolf runs at the herd, trying to flush out the weak or the slow. 343 00:46:00,580 --> 00:46:02,620 A calf is separated. 344 00:46:10,500 --> 00:46:15,140 At full tilt, 40-miles-an-hour, the wolf is just faster. 345 00:46:23,460 --> 00:46:25,940 But the calf has stamina. 346 00:46:55,380 --> 00:46:57,540 Only a few weeks old 347 00:46:57,540 --> 00:47:01,620 and this calf's will to survive is remarkable. 348 00:47:06,140 --> 00:47:08,540 And it needs to be, 349 00:47:08,540 --> 00:47:11,340 for these young caribou have now started a journey 350 00:47:11,340 --> 00:47:13,980 that will last a lifetime... 351 00:47:16,820 --> 00:47:20,500 ..forever chasing the seasonal growth of the grass 352 00:47:20,500 --> 00:47:22,100 on which they depend. 353 00:47:30,860 --> 00:47:32,700 Like all grassland creatures, 354 00:47:32,700 --> 00:47:36,180 they are at the mercy of these unpredictable, 355 00:47:36,180 --> 00:47:38,980 but ultimately bountiful lands. 356 00:47:44,700 --> 00:47:49,020 Grass can survive some of the harshest conditions on Earth - 357 00:47:49,020 --> 00:47:53,380 flood, fire, and frost - and still flourish. 358 00:48:03,260 --> 00:48:07,060 So it is, the grasslands provide a stage 359 00:48:07,060 --> 00:48:11,140 for the greatest gatherings of wildlife on planet Earth. 360 00:48:25,020 --> 00:48:29,340 For the grasslands team, no location would prove as challenging 361 00:48:29,340 --> 00:48:33,820 as that dominated by elephant grass in north-east India. 362 00:48:33,820 --> 00:48:36,380 The aim, to capture intimate images 363 00:48:36,380 --> 00:48:39,180 of some of the world's most elusive creatures 364 00:48:39,180 --> 00:48:42,300 using the latest technology. 365 00:48:48,900 --> 00:48:51,300 But they will need to be careful. 366 00:48:55,380 --> 00:48:56,900 ELEPHANT TRUMPETS 367 00:48:56,900 --> 00:48:59,540 More people are killed by wildlife here in Kaziranga... 368 00:48:59,540 --> 00:49:00,820 ELEPHANT ROARS 369 00:49:02,340 --> 00:49:05,380 ..than in any other national park on the planet. 370 00:49:06,940 --> 00:49:09,220 Every time we go into these tunnels, 371 00:49:09,220 --> 00:49:11,300 we have to take an armed guard 372 00:49:11,300 --> 00:49:14,820 because there are so many animals in here that are dangerous. 373 00:49:14,820 --> 00:49:16,700 Tigers are probably the least of our worries. 374 00:49:16,700 --> 00:49:19,420 But rhinos and buffalo, elephants, 375 00:49:19,420 --> 00:49:22,140 sloth bear - all of them can injure you 376 00:49:22,140 --> 00:49:24,260 and we've got to keep up with our armed guard! 377 00:49:29,700 --> 00:49:32,460 The team have bumped into their first obstacle. 378 00:49:33,620 --> 00:49:34,940 There's a rhino right there. 379 00:49:38,460 --> 00:49:40,940 Let's go back, because it's too risky 380 00:49:40,940 --> 00:49:43,140 going through this heavy grass. 381 00:49:45,300 --> 00:49:46,420 Let's get in the open. 382 00:49:47,900 --> 00:49:49,260 Another rhino. 383 00:49:51,300 --> 00:49:53,460 Now we have two rhinos. Let's get in here. 384 00:49:54,940 --> 00:49:55,940 GUARD SHOUTS 385 00:49:55,940 --> 00:49:57,980 OK. 386 00:49:57,980 --> 00:50:00,740 The guard throws a ball of mud to one side of the rhinos, 387 00:50:00,740 --> 00:50:06,780 moving the animals on without harming them. 388 00:50:11,700 --> 00:50:14,100 OK, it's gone. OK. 389 00:50:14,100 --> 00:50:15,860 What about the other one? 390 00:50:15,860 --> 00:50:17,100 Let's go, quick. 391 00:50:20,900 --> 00:50:23,900 With the rhinos now a safe distance away, 392 00:50:23,900 --> 00:50:25,700 the crew focus on the best spots 393 00:50:25,700 --> 00:50:28,060 to position their camera traps. 394 00:50:28,060 --> 00:50:30,460 I love that tunnel. The effect. 395 00:50:34,380 --> 00:50:37,460 Over 100 scaffold poles provide the anchor points 396 00:50:37,460 --> 00:50:40,220 for these secret cameras. 397 00:50:40,220 --> 00:50:43,620 When an animal triggers an infrared beam, 398 00:50:43,620 --> 00:50:46,620 the cameras will switch on automatically and start recording. 399 00:50:46,620 --> 00:50:48,860 If it works, 400 00:50:48,860 --> 00:50:52,140 the remote-control cameras should capture close-up footage 401 00:50:52,140 --> 00:50:56,140 without disturbing the animals or putting the crew at risk. 402 00:50:56,140 --> 00:51:00,340 Basically, that's about as much like grass as we can make it look. 403 00:51:02,180 --> 00:51:06,020 As night falls, the crew head back to base for safety. 404 00:51:07,500 --> 00:51:11,580 It's time for the new technology to prove its worth. 405 00:51:16,980 --> 00:51:21,940 At dawn, the crew have a whodunnit mystery on their hands. 406 00:51:21,940 --> 00:51:24,860 Oh, wow! 407 00:51:24,860 --> 00:51:26,180 That's carnage. 408 00:51:27,460 --> 00:51:29,300 This looks like elephant, we think. 409 00:51:30,620 --> 00:51:33,660 This is scaffold pole, huh. 410 00:51:33,660 --> 00:51:35,820 They have bent... Look at that! 411 00:51:38,740 --> 00:51:42,460 It's a sad day. You win some, you lose some 412 00:51:42,460 --> 00:51:45,900 and, this time, the animals have outsmarted us. 413 00:51:45,900 --> 00:51:48,580 And, in fact, check this out! 414 00:51:48,580 --> 00:51:49,940 Woohoo! 415 00:51:49,940 --> 00:51:54,580 So, this is our little army of guards, protecting our trigger box. 416 00:51:54,580 --> 00:51:56,820 Do they bite? These ones? 417 00:51:56,820 --> 00:51:59,540 Do they bite? Sting? 418 00:51:59,540 --> 00:52:02,060 Argh! Argh. Ow! Oh. 419 00:52:02,060 --> 00:52:04,540 These little... BLEEP! 420 00:52:07,500 --> 00:52:10,740 While Chadden irons out the bugs, 421 00:52:10,740 --> 00:52:14,100 Sandesh has met some grumpy locals. 422 00:52:17,540 --> 00:52:21,380 Wild Asian water buffalo have extraordinary senses. 423 00:52:23,340 --> 00:52:26,260 Mothers will charge if they feel threatened. 424 00:52:28,900 --> 00:52:32,460 The guard carries a gun in case a warning shot is needed, 425 00:52:32,460 --> 00:52:34,340 and with good reason. 426 00:52:35,980 --> 00:52:38,900 More people are killed by buffalo 427 00:52:38,900 --> 00:52:42,620 than by any other animal in Kaziranga. 428 00:52:47,580 --> 00:52:49,540 GUARD SHOUTS A WARNING 429 00:52:49,540 --> 00:52:51,460 That will wake you up in the morning! 430 00:52:51,460 --> 00:52:55,700 Many of the park staff have cautionary tales about buffalo. 431 00:52:55,700 --> 00:52:59,900 HE SPEAKS IN HIS LANGUAGE 432 00:52:59,900 --> 00:53:02,020 The buffalo caught him here. 433 00:53:02,020 --> 00:53:06,860 Through his throat, and the horn came out through his mouth 434 00:53:06,860 --> 00:53:12,380 and flung him, before running away. 435 00:53:14,220 --> 00:53:17,100 If the wildlife is unfriendly to humans... 436 00:53:18,140 --> 00:53:21,860 ..it's proving downright hostile to camera traps. 437 00:53:21,860 --> 00:53:25,380 Completely ripped-out the scaffold poles. 438 00:53:25,380 --> 00:53:29,460 They've torn the triggers. 439 00:53:29,460 --> 00:53:31,860 While Chadden is convinced it's elephants, 440 00:53:31,860 --> 00:53:34,900 the rest of the crew are not so sure. 441 00:53:34,900 --> 00:53:38,180 That's huge! It's almost like a human footprint. 442 00:53:38,180 --> 00:53:41,220 You can see the front paw, the rear paw. 443 00:53:41,220 --> 00:53:46,140 We are now two weeks in and it's very frustrating. 444 00:53:46,140 --> 00:53:49,260 I've never actually been anywhere where the animals 445 00:53:49,260 --> 00:53:52,420 go after your equipment and destroy it, more than here. 446 00:53:52,420 --> 00:53:56,660 It's time for the team to do some detective work. 447 00:53:58,100 --> 00:54:01,220 Here is our little security camera. 448 00:54:01,220 --> 00:54:04,940 If any animals are coming through and vandalising our main cameras, 449 00:54:04,940 --> 00:54:09,340 we hope that they're being caught on these little things. 450 00:54:09,340 --> 00:54:10,460 Good. 451 00:54:11,740 --> 00:54:14,140 As the crew up their spying efforts, 452 00:54:14,140 --> 00:54:16,780 the guards take them to a promising lead. 453 00:54:16,780 --> 00:54:21,500 Nothing attracts tigers like a rhino carcass. 454 00:54:21,500 --> 00:54:22,780 It's very fresh. 455 00:54:22,780 --> 00:54:26,940 It's like from the morning. And it looks like there's a tiger cub. 456 00:54:26,940 --> 00:54:29,780 So there should be a tigress with cubs 457 00:54:29,780 --> 00:54:34,860 coming to feed on this rhino carcass. That's pretty cool. 458 00:54:34,860 --> 00:54:38,860 Chadden decides to give the camera traps one last chance. 459 00:54:38,860 --> 00:54:40,940 If there are tigers around, 460 00:54:40,940 --> 00:54:44,780 they might scare away the mystery vandals. 461 00:54:44,780 --> 00:54:47,060 Elsewhere in the park, 462 00:54:47,060 --> 00:54:51,060 the security cameras are turning up some unexpected results. 463 00:54:51,060 --> 00:54:54,540 The night-time... Yeah. Survived another... Ooh! 464 00:54:54,540 --> 00:54:57,460 It's a bear! 465 00:54:57,460 --> 00:54:59,420 Well, that's a very rare sighting. 466 00:54:59,420 --> 00:55:03,500 I've never seen a bear in Kaziranga. Haven't you? In all my years, never. 467 00:55:03,500 --> 00:55:07,220 Oh, his fingernails... Look at those, look at his claws. 468 00:55:07,220 --> 00:55:08,460 Right on the lens. 469 00:55:08,460 --> 00:55:11,620 So, I thought this was elephant damage. 470 00:55:11,620 --> 00:55:17,540 I never thought we'd see a sloth bear doing that. 471 00:55:21,100 --> 00:55:23,700 A return to the rhino carcass 472 00:55:23,700 --> 00:55:25,460 and the plot thickens. 473 00:55:26,900 --> 00:55:29,020 Our transmitter's gone. 474 00:55:29,020 --> 00:55:30,700 That's what tigers think of camera traps. 475 00:55:30,700 --> 00:55:34,100 There's a bit over there, pieces. 476 00:55:34,100 --> 00:55:37,620 The security cameras have caught a new culprit. 477 00:55:37,620 --> 00:55:40,420 Oh, my goodness! There they are. Oh! 478 00:55:40,420 --> 00:55:41,860 There's the tigress, see that? 479 00:55:41,860 --> 00:55:45,420 It's a tigress. Oh, it snarled at the camera trap. Look at that! 480 00:55:45,420 --> 00:55:47,260 Sure don't like camera traps. 481 00:55:47,260 --> 00:55:48,300 OK. 482 00:55:49,940 --> 00:55:52,020 With the technology struggling, 483 00:55:52,020 --> 00:55:56,300 Sandesh decides to put himself on the front line. 484 00:55:56,300 --> 00:55:58,540 And now we're ready. 485 00:55:58,540 --> 00:55:59,940 Time to get the tiger. 486 00:56:01,500 --> 00:56:05,380 He'll have no protection apart from a thin wall of grass 487 00:56:05,380 --> 00:56:09,060 and must hope he's as well hidden as the local wildlife. 488 00:56:11,540 --> 00:56:13,180 Over the next five days, 489 00:56:13,180 --> 00:56:16,540 Sandesh plays the role of human camera trap. 490 00:56:19,500 --> 00:56:23,300 Eventually, the more hands-on approach pays off. 491 00:56:49,300 --> 00:56:52,540 Traditional filming methods and a little bit of patience 492 00:56:52,540 --> 00:56:57,100 have helped reveal the hidden creatures of Kaziranga. 493 00:57:02,700 --> 00:57:05,860 But it's good to know there are still wild places 494 00:57:05,860 --> 00:57:09,260 where animals like to keep their secrets. 495 00:57:12,340 --> 00:57:15,180 EQUIPMENT CREAKS AND THUDS 496 00:57:15,180 --> 00:57:16,660 I knew it was elephants! 497 00:57:19,780 --> 00:57:22,220 Next time, 498 00:57:22,220 --> 00:57:25,460 we venture to the newest habitat on Earth - 499 00:57:25,460 --> 00:57:27,540 our cities - 500 00:57:27,540 --> 00:57:31,220 to reveal the extraordinary ways 501 00:57:31,220 --> 00:57:35,020 that animals survive in this man-made world.