1 00:00:03,120 --> 00:00:05,122 (THEME MUSIC PLAYING) 2 00:00:33,520 --> 00:00:34,885 (BIRDS CHIRPING) 3 00:00:34,960 --> 00:00:37,725 DAVID ATTENBOROUGH: One quarter of all the land on Earth 4 00:00:37,800 --> 00:00:41,361 is covered by a single, remarkable type of plant. 5 00:00:47,760 --> 00:00:52,129 Almost indestructible, it can grow two feet in a day... 6 00:00:58,560 --> 00:01:01,882 And be tall enough to hide a giant. 7 00:01:02,560 --> 00:01:04,244 (GRUNTING) 8 00:01:06,200 --> 00:01:08,521 That plant is grass, 9 00:01:08,600 --> 00:01:11,888 and the world it creates is truly unique. 10 00:01:25,440 --> 00:01:29,161 The grass in northern India is the tallest on the planet, 11 00:01:29,320 --> 00:01:33,370 home to some of the most impressive creatures to tread the Earth. 12 00:01:37,920 --> 00:01:39,206 (GRUNTS) 13 00:01:47,120 --> 00:01:48,281 (TRUMPETS) 14 00:01:48,360 --> 00:01:50,488 These are the good times, 15 00:01:50,560 --> 00:01:54,201 but in just a few months, all this fresh growth will be gone, 16 00:01:54,760 --> 00:01:57,843 and the animals will be forced to move on. 17 00:02:00,560 --> 00:02:05,168 That is the way things are on grasslands across the planet. 18 00:02:08,840 --> 00:02:13,050 A cycle of abundance, destruction and rebirth 19 00:02:13,400 --> 00:02:15,721 that affects every creature that lives here. 20 00:02:23,000 --> 00:02:24,923 (ELEPHANTS GRUNTING) 21 00:02:30,640 --> 00:02:35,248 The largest grassland on Earth, the vast Eurasian Steppe, 22 00:02:35,680 --> 00:02:39,082 stretches one third of the way around our planet. 23 00:02:43,400 --> 00:02:48,566 Spring rain has brought fresh grass, and with it, new life. 24 00:02:52,760 --> 00:02:57,402 A relic from the Ice Age, a baby Saiga antelope, 25 00:02:57,680 --> 00:02:59,489 just three hours old. 26 00:03:02,680 --> 00:03:04,921 His only company, his twin. 27 00:03:06,240 --> 00:03:10,848 Until they can stand, their mother has left them hidden in the grass. 28 00:03:18,560 --> 00:03:22,485 They should be safe, as long as they remain quiet. 29 00:03:24,640 --> 00:03:25,641 (CALLS) 30 00:03:27,480 --> 00:03:30,370 For these calves, the clock is already ticking. 31 00:03:31,920 --> 00:03:36,562 Their herd will soon be moving on, seeking the freshest new grass. 32 00:03:40,280 --> 00:03:41,566 (CALLS) 33 00:03:53,840 --> 00:03:58,402 Their lanky legs are a sure sign that they're built for a life on the move. 34 00:04:22,760 --> 00:04:25,684 Saiga always give birth to twins, 35 00:04:25,760 --> 00:04:29,287 so their numbers grow rapidly just when grass is plentiful. 36 00:04:32,680 --> 00:04:36,048 Their bizarrely shaped nose can detect fresh growth 37 00:04:36,360 --> 00:04:38,328 from hundreds of miles away. 38 00:04:42,240 --> 00:04:44,049 (SAIGAS BAWLING) 39 00:04:50,080 --> 00:04:53,323 The young twins will now begin the nomadic life 40 00:04:53,520 --> 00:04:57,605 they share with most animals on the world's open plains. 41 00:05:12,200 --> 00:05:13,406 (THUNDER RUMBLING) 42 00:05:18,760 --> 00:05:24,369 Grasslands occur where rain is too sporadic for forests to exist. 43 00:05:34,520 --> 00:05:37,888 The rain that a grassland needs to survive for a year 44 00:05:38,160 --> 00:05:40,242 might arrive all at once. 45 00:05:44,120 --> 00:05:45,246 (LIGHTNING CRACKS) 46 00:06:00,840 --> 00:06:05,846 Storms like these can release 12 inches of rain in 24 hours. 47 00:06:05,920 --> 00:06:07,445 (HEAVY RAINFALL) 48 00:06:16,600 --> 00:06:19,251 Not much fun if you're out in it. 49 00:06:30,960 --> 00:06:34,248 Eventually the earth can't soak up any more, 50 00:06:34,840 --> 00:06:36,365 (THUNDER CRACKING) 51 00:06:37,120 --> 00:06:40,567 and the grassland undergoes a radical change. 52 00:06:41,480 --> 00:06:43,323 (WATER FLOWING) 53 00:06:47,400 --> 00:06:51,883 Many plants would drown here, but grasses thrive. 54 00:06:55,000 --> 00:06:56,126 They grow so fast, 55 00:06:56,200 --> 00:06:59,568 their leaves quickly rise above the water and into the sunlight. 56 00:07:04,200 --> 00:07:05,964 Here in southern Africa, 57 00:07:06,040 --> 00:07:10,602 water transforms one of the most remarkable grasslands on Earth, 58 00:07:13,160 --> 00:07:14,207 the Okavango. 59 00:07:17,920 --> 00:07:22,244 Every year, 5,000 square miles of grassland are flooded. 60 00:07:30,200 --> 00:07:34,205 For one pride of lions, this poses a major problem. 61 00:07:36,520 --> 00:07:38,921 There may be plenty of prey around, 62 00:07:39,000 --> 00:07:41,685 but lions struggle to run it down in water. 63 00:07:48,760 --> 00:07:53,607 The pride has three-month-old cubs. They've never seen water before. 64 00:07:54,320 --> 00:07:55,810 (CUBS MEOWING) 65 00:07:57,520 --> 00:07:59,648 If their mothers don't make a kill soon, 66 00:08:00,240 --> 00:08:02,766 the cubs might not survive the week. 67 00:08:03,680 --> 00:08:04,806 (YOWLS) 68 00:08:12,160 --> 00:08:17,769 But fuelled by the flood, the eruption of grass attracts new possible prey. 69 00:08:20,960 --> 00:08:24,009 Buffalo arrive in herds 2,000 strong. 70 00:08:30,360 --> 00:08:31,407 (GRUNTS) 71 00:08:31,480 --> 00:08:34,404 Powerful, aggressive and united, 72 00:08:34,800 --> 00:08:37,690 they're the most dangerous animal a lion can face. 73 00:09:01,880 --> 00:09:02,881 (BUFFALO GRUNTS) 74 00:09:15,040 --> 00:09:17,247 The biggest bulls don't run. 75 00:09:19,560 --> 00:09:22,848 They're simply too huge to be scared of lions. 76 00:09:25,320 --> 00:09:30,201 At 900 kilos, he weighs more than all five lionesses combined. 77 00:09:34,640 --> 00:09:37,086 The pride do have numbers on their side, 78 00:09:38,720 --> 00:09:41,564 but one sweep of his horns could be deadly. 79 00:09:55,360 --> 00:09:59,649 One distracts the bull up front, while her sisters attack from behind. 80 00:10:10,520 --> 00:10:12,807 The cats must somehow topple the buffalo, 81 00:10:13,000 --> 00:10:16,163 but with swamp under foot, they can't get any traction. 82 00:10:59,240 --> 00:11:00,844 The bull is weakening, 83 00:11:01,720 --> 00:11:03,882 but the lions are tiring, too. 84 00:11:08,880 --> 00:11:12,521 It's now a battle of will as much as strength. 85 00:11:15,680 --> 00:11:19,162 To live, the bull must somehow shake off the lioness. 86 00:11:21,280 --> 00:11:23,282 (DRAMATIC INSTRUMENTAL MUSIC) 87 00:11:57,000 --> 00:11:58,570 The bull is wounded, 88 00:11:58,640 --> 00:12:02,361 but thanks to his two-inch-thick hide, he will recover. 89 00:12:08,200 --> 00:12:11,522 For the pride, these are hungry times. 90 00:12:11,600 --> 00:12:12,965 (CUB WHIMPERS) 91 00:12:19,640 --> 00:12:24,407 But, ultimately, once the water recedes, there will be new life, 92 00:12:25,400 --> 00:12:27,562 and new food to benefit all. 93 00:12:36,720 --> 00:12:40,645 In the right conditions, grasses have the extraordinary ability 94 00:12:40,720 --> 00:12:45,487 to grow from first shoots to flower in a matter of only days. 95 00:12:52,080 --> 00:12:56,290 Grasses become the miniature equivalents of fruiting trees. 96 00:13:02,000 --> 00:13:03,525 (CRICKET CHIRPS) 97 00:13:03,600 --> 00:13:06,171 And for creatures living within the grass, 98 00:13:06,240 --> 00:13:10,529 this is a landscape as vast and towering as any rainforest. 99 00:13:15,600 --> 00:13:18,490 And excellent place to build a tiny tree house 100 00:13:21,000 --> 00:13:22,206 for a harvest mouse. 101 00:13:27,320 --> 00:13:28,321 (SQUEAKS) 102 00:13:34,280 --> 00:13:38,410 During summer, European meadowlands are full of food, 103 00:13:41,760 --> 00:13:43,967 but only for those that can reach it. 104 00:14:00,360 --> 00:14:01,885 (STEM CRACKS) 105 00:14:02,400 --> 00:14:05,370 Climbing grass is harder than climbing trees, 106 00:14:05,520 --> 00:14:08,763 not least because their stems just won't stay still. 107 00:14:16,520 --> 00:14:19,888 Her prehensile tail acts like a fifth limb, 108 00:14:19,960 --> 00:14:23,965 so she's as agile as a monkey clambering around in a tree. 109 00:14:25,640 --> 00:14:26,641 (STEM CREAKS) 110 00:14:31,680 --> 00:14:32,966 And just as well, 111 00:14:33,320 --> 00:14:37,689 for the best food in this tiny forest is at the very top of its canopy. 112 00:14:48,440 --> 00:14:51,364 Feeding up here, she's exposed. 113 00:14:58,720 --> 00:14:59,881 A barn owl. 114 00:15:30,800 --> 00:15:32,643 Not her finest move... 115 00:15:36,440 --> 00:15:37,646 But it did the trick. 116 00:15:39,800 --> 00:15:43,202 Harvest mice seldom go all the way down to the ground. 117 00:15:46,480 --> 00:15:49,768 It's a tangled and dangerous world down here. 118 00:15:52,520 --> 00:15:54,648 (INSECTS CHITTERING) 119 00:16:03,000 --> 00:16:07,210 But she can read the pattern of the stems overhead like a map, 120 00:16:08,320 --> 00:16:10,209 and so find her way home. 121 00:16:18,240 --> 00:16:20,686 And not a minute too soon. 122 00:16:25,240 --> 00:16:27,288 There are mouths to feed. 123 00:16:36,360 --> 00:16:38,010 (SNIFFS) 124 00:16:41,040 --> 00:16:43,168 Her babies must fatten up quickly. 125 00:16:45,440 --> 00:16:49,923 They need to harvest the summer grasses while they're still rich with food. 126 00:16:58,360 --> 00:17:03,127 On the African savannah, too, seasonal grasses are filled with life, 127 00:17:03,640 --> 00:17:05,005 but it won't last long. 128 00:17:08,560 --> 00:17:11,848 Carmine bee-eaters are superb aerial hunters, 129 00:17:13,560 --> 00:17:17,007 experts at catching insects in midair. 130 00:17:24,360 --> 00:17:27,807 But they have no way of flushing their prey out of the grass. 131 00:17:35,800 --> 00:17:37,450 (INSECTS CHITTERING) 132 00:17:37,920 --> 00:17:41,129 Once alarmed, most insects stay put. 133 00:17:44,480 --> 00:17:48,121 The bee-eaters need someone to stir things up a bit. 134 00:17:48,200 --> 00:17:49,486 (CALLS) 135 00:17:54,040 --> 00:17:55,166 A kori bustard. 136 00:18:00,200 --> 00:18:02,521 It's the world's heaviest flying bird, 137 00:18:02,600 --> 00:18:05,251 so it should be bulky enough to kick up some insects. 138 00:18:11,560 --> 00:18:12,561 (INSECT BUZZING) 139 00:18:13,240 --> 00:18:14,241 Bingo! 140 00:18:17,200 --> 00:18:22,240 Until someone else comes along and cramps your style. 141 00:18:26,400 --> 00:18:27,401 (CHIRPS) 142 00:18:28,160 --> 00:18:32,210 Never mind, perhaps there are bigger opportunities ahead. 143 00:18:35,360 --> 00:18:37,010 What about an ostrich? 144 00:18:39,680 --> 00:18:41,011 The heaviest bird of all. 145 00:18:46,920 --> 00:18:50,561 This time there's more than enough transport to go around. 146 00:18:52,000 --> 00:18:53,001 (SQUAWKING) 147 00:19:00,600 --> 00:19:04,491 Soon, almost every ostrich has its own passenger. 148 00:19:12,240 --> 00:19:15,926 But free riders are only tolerated for so long. 149 00:19:22,480 --> 00:19:24,608 What the bee-eaters really need 150 00:19:24,680 --> 00:19:27,923 is a creature so big it won't even notice them. 151 00:19:32,640 --> 00:19:33,880 (GRUNTING) 152 00:19:38,120 --> 00:19:43,206 Nothing cuts a swathe through grass like an African bull elephant. 153 00:19:59,520 --> 00:20:03,525 The trick is to fly as close to the front of the giant as possible. 154 00:20:04,160 --> 00:20:07,323 They only have a split second to grab the prize. 155 00:20:17,000 --> 00:20:21,164 As more insects are stirred up, the competition intensifies. 156 00:20:24,080 --> 00:20:26,287 (FRENZIED CHIRPING) 157 00:20:43,120 --> 00:20:47,569 With summer drawing to a close, the race to stock up is on. 158 00:20:52,800 --> 00:20:57,840 Soon, the grass will wither, and this opportunity will have gone. 159 00:21:07,360 --> 00:21:09,931 As the dry season takes hold, 160 00:21:10,000 --> 00:21:12,651 food becomes increasingly thin on the ground. 161 00:21:15,320 --> 00:21:20,201 Now, only the most specialised predators on the plains can make a living. 162 00:21:25,720 --> 00:21:30,362 She may be spotted like a cheetah, but this cat is no sprinter. 163 00:21:43,080 --> 00:21:48,405 Instead, she has extra-long legs which give her a high vantage point. 164 00:21:59,480 --> 00:22:04,611 But a serval cat's main weapon are enormous radar ears. 165 00:22:05,040 --> 00:22:06,041 (GRASS RUSTLING) 166 00:22:08,800 --> 00:22:11,929 They help her pinpoint prey hiding in the grass. 167 00:22:20,760 --> 00:22:23,730 But the prey she seeks are canny. 168 00:22:27,520 --> 00:22:28,931 Southern vlei rats. 169 00:22:32,200 --> 00:22:35,568 They know that any sustained movement can give them away. 170 00:22:41,200 --> 00:22:43,680 So they move in short bursts. 171 00:22:43,800 --> 00:22:44,847 (RUSTLING) 172 00:22:51,600 --> 00:22:54,843 But even the slightest rustle will give her a clue. 173 00:22:55,040 --> 00:22:56,041 (RUSTLING) 174 00:23:17,120 --> 00:23:18,121 Warm. 175 00:23:24,680 --> 00:23:25,681 (RUSTLING) 176 00:23:27,280 --> 00:23:28,281 (RUSTLES) 177 00:23:30,480 --> 00:23:31,606 Warmer. 178 00:23:45,880 --> 00:23:46,961 Missed. 179 00:24:20,760 --> 00:24:21,761 (RUSTLING) 180 00:24:33,400 --> 00:24:34,401 (ANIMAL CALLS) 181 00:24:43,760 --> 00:24:44,761 (RUSTLING) 182 00:25:01,320 --> 00:25:02,321 (SQUEAKS) 183 00:25:06,440 --> 00:25:09,523 In better times, she could catch 10 a day, 184 00:25:10,880 --> 00:25:15,363 but now, with so few rodents around, she will have to go hungry. 185 00:25:17,720 --> 00:25:22,169 As drought intensifies, life gets tougher for all. 186 00:25:28,920 --> 00:25:32,561 Predators with permanent territories must tough it out, 187 00:25:33,320 --> 00:25:37,291 while most of their prey disappear over the horizon. 188 00:25:38,200 --> 00:25:40,009 (GRUNTING) 189 00:25:41,520 --> 00:25:47,084 To avoid starvation, many grassland animals follow a nomadic way of life. 190 00:25:49,440 --> 00:25:53,490 Over 2,000,000 wildebeests wander the East African savannahs 191 00:25:53,560 --> 00:25:55,244 chasing the rains. 192 00:26:08,880 --> 00:26:10,962 And they are not alone. 193 00:26:13,320 --> 00:26:14,810 Arriving on the wing, 194 00:26:14,880 --> 00:26:18,566 Jackson's Widowbirds also seek fresh grass. 195 00:26:18,800 --> 00:26:19,801 (CHIRPING) 196 00:26:20,600 --> 00:26:23,968 Although, it's not just food that they're after. 197 00:26:25,960 --> 00:26:26,961 (CHIRPS) 198 00:26:28,520 --> 00:26:30,602 This male wants a mate. 199 00:26:33,760 --> 00:26:36,764 He's grown elaborate breeding plumage for this moment, 200 00:26:38,800 --> 00:26:41,690 but he needs a stage on which to show it off. 201 00:26:46,040 --> 00:26:50,364 By carefully selecting grass blades, each trimmed to the correct length, 202 00:26:51,080 --> 00:26:53,242 he's creating something very special. 203 00:27:08,200 --> 00:27:10,771 He needs an even surface, 204 00:27:12,800 --> 00:27:14,131 and a centre-piece. 205 00:27:16,920 --> 00:27:18,285 The stage is set. 206 00:27:19,640 --> 00:27:24,123 His bachelor pad is sufficiently neat and tidy to attract a female. 207 00:27:25,960 --> 00:27:27,007 The problem is, 208 00:27:27,480 --> 00:27:28,641 can she see it? 209 00:27:28,720 --> 00:27:29,721 (CHIRPS) 210 00:27:32,680 --> 00:27:33,806 He has competition. 211 00:27:33,880 --> 00:27:35,245 (CHIRPING LOUDER) 212 00:27:44,160 --> 00:27:48,324 It might take more than a little gardening to impress the ladies. 213 00:27:50,760 --> 00:27:52,603 Jumping is the right idea, 214 00:27:53,960 --> 00:27:56,327 but he's misjudged the height of the grass. 215 00:28:06,240 --> 00:28:08,163 His rival makes it look easy. 216 00:28:31,400 --> 00:28:33,482 Time to raise his game. 217 00:28:38,440 --> 00:28:40,727 (BOTH CHIRPING) 218 00:29:09,080 --> 00:29:13,802 It's not only who jumps the highest, but who can keep doing so the longest. 219 00:29:22,880 --> 00:29:27,647 Unable to go the distance, his rivals drop out one by one. 220 00:29:32,280 --> 00:29:35,409 Stamina has won him admirers, 221 00:29:36,840 --> 00:29:40,003 now he can show off his courtship arena... 222 00:29:49,440 --> 00:29:53,081 And engage in a little romantic hide-and-seek. 223 00:30:05,000 --> 00:30:07,606 Finally, he's done enough. 224 00:30:19,320 --> 00:30:23,484 The East African savannahs support millions of grazers. 225 00:30:23,560 --> 00:30:24,561 (GRUNTING) 226 00:30:24,800 --> 00:30:28,282 Each year they devour millions of tons of grass, 227 00:30:30,440 --> 00:30:32,568 and yet there's one creature here 228 00:30:32,640 --> 00:30:37,521 whose impact is far greater than all these animals combined. 229 00:30:41,560 --> 00:30:44,530 They're found wherever grass grows on the planet, 230 00:30:45,280 --> 00:30:48,409 yet their labours go almost entirely unnoticed. 231 00:30:53,320 --> 00:30:58,804 One of the most remarkable is found here on the grasslands of South America. 232 00:31:01,760 --> 00:31:07,483 These blades are so tough that virtually no large grass eaters can stomach them. 233 00:31:08,720 --> 00:31:12,361 Yet they're harvested on an industrial scale... 234 00:31:13,000 --> 00:31:14,001 (CRACKING) 235 00:31:16,360 --> 00:31:19,011 ...by tiny grass cutter ants. 236 00:31:25,920 --> 00:31:28,685 But they themselves can't digest one bit of it. 237 00:31:31,920 --> 00:31:33,251 So, why bother? 238 00:31:37,600 --> 00:31:40,080 The answer is underground, 239 00:31:42,120 --> 00:31:44,168 and it's very ingenious. 240 00:31:48,840 --> 00:31:54,131 Each blade is cut to length and placed into a garden of fungus. 241 00:31:59,120 --> 00:32:05,526 The rotting grass feeds the fungus, and in turn the fungus feeds the ants. 242 00:32:09,120 --> 00:32:13,444 But feeding 5,000,000 workers requires intensive agriculture. 243 00:32:16,040 --> 00:32:19,283 Luckily, they are an industrious lot. 244 00:32:23,760 --> 00:32:28,687 This colony alone will collect over half a ton of grass every year. 245 00:32:32,880 --> 00:32:36,248 With billions of ant colonies across the world's grasslands 246 00:32:36,400 --> 00:32:41,804 all doing exactly the same thing, that's a mind-boggling amount of grass. 247 00:33:10,040 --> 00:33:13,965 It's estimated that over one third of the grass that grows on Earth 248 00:33:14,440 --> 00:33:17,091 will be harvested by an insect. 249 00:33:23,160 --> 00:33:29,008 In northern Australia, termites memorialise their industry in sculpture. 250 00:33:36,960 --> 00:33:40,009 These astonishing mounds are 10 feet tall. 251 00:33:40,760 --> 00:33:43,684 They're always built on a north-south axis, 252 00:33:43,760 --> 00:33:47,048 which is why their builders are called compass termites. 253 00:34:00,600 --> 00:34:02,329 These castles of clay 254 00:34:02,400 --> 00:34:05,131 protect their builders from extremes of heat 255 00:34:05,200 --> 00:34:09,046 and seasonal floods experienced on many grasslands. 256 00:34:20,560 --> 00:34:24,849 Termites manage to do what most grass eaters can't, 257 00:34:25,920 --> 00:34:29,242 break down dead grass and extract the nutrients. 258 00:34:30,600 --> 00:34:34,491 But they themselves can be food for those that can reach them. 259 00:34:35,240 --> 00:34:36,571 (SUCKING NOISE) 260 00:34:40,160 --> 00:34:41,924 A two-foot-long tongue 261 00:34:43,240 --> 00:34:45,368 covered in microscopic hooks, 262 00:34:48,760 --> 00:34:53,129 followed by claws longer than those of a velociraptor. 263 00:34:55,720 --> 00:34:56,721 (SNIFFING) 264 00:34:59,320 --> 00:35:02,767 A giant anteater on the plains of South America. 265 00:35:04,040 --> 00:35:05,041 (SLURPING) 266 00:35:07,720 --> 00:35:10,803 It can devour 20,000 insects a day. 267 00:35:16,080 --> 00:35:21,325 Powerful forelegs enable it to rip apart a termite hill with ease. 268 00:35:31,320 --> 00:35:36,451 And as the sun bakes the grass, the termites face new danger. 269 00:35:45,000 --> 00:35:46,525 (FIRE CRACKLES) 270 00:35:58,520 --> 00:36:02,605 In minutes, fire turns grassland to ash. 271 00:36:16,480 --> 00:36:22,010 But the grasses are not dead. Their underground stems are unharmed. 272 00:36:25,280 --> 00:36:27,647 Weeks, months may pass, 273 00:36:28,080 --> 00:36:32,802 but eventually the rains will return and the grass will sprout again. 274 00:36:39,920 --> 00:36:45,131 Some grasslands must endure not only fire, but ice. 275 00:36:50,440 --> 00:36:55,128 As winter approaches, the prairies of North America begin to freeze. 276 00:36:56,400 --> 00:36:57,401 (CRACKING) 277 00:37:05,520 --> 00:37:07,090 (LOW GROWLING) 278 00:37:11,120 --> 00:37:13,646 In summer, bison roamed freely, 279 00:37:13,720 --> 00:37:17,202 almost continuously cropping the abundant green grass. 280 00:37:19,120 --> 00:37:24,331 Now, that grass is not only withered and frozen, it's about to be buried. 281 00:37:45,880 --> 00:37:50,568 Sixty million tons of snow now blanket this herd's territory. 282 00:37:52,520 --> 00:37:53,681 (SNORTING) 283 00:37:54,600 --> 00:37:57,843 Pushing through deep snow is exhausting work, 284 00:37:57,920 --> 00:38:00,526 and the bison are now slowly starving. 285 00:38:07,520 --> 00:38:10,808 Just keeping warm saps huge amounts of energy. 286 00:38:11,800 --> 00:38:13,723 (GROWLS) 287 00:38:17,320 --> 00:38:21,450 Their thick coats can insulate them down to minus 20 Fahrenheit. 288 00:38:22,360 --> 00:38:24,283 It's now minus 40. 289 00:38:27,280 --> 00:38:32,923 The only thing that will keep them alive is buried beneath three feet of snow. 290 00:38:37,560 --> 00:38:41,042 And that's a problem shared with a surprising neighbour. 291 00:38:58,920 --> 00:39:02,561 The food the fox seeks is also deep beneath the snow. 292 00:39:10,240 --> 00:39:11,685 (GRUNTING) 293 00:39:14,920 --> 00:39:19,562 The survival of both creatures depends on getting through to the ground. 294 00:39:25,040 --> 00:39:28,647 For the bison, it will be a matter of brute strength. 295 00:39:33,400 --> 00:39:38,088 Massive neck muscles enable them to shovel five tonnes of snow a day. 296 00:39:44,560 --> 00:39:47,484 Their light-weight neighbour needs more precision. 297 00:40:07,920 --> 00:40:08,921 (CHEWING) 298 00:40:15,080 --> 00:40:17,048 The bison have reached their goal, 299 00:40:17,840 --> 00:40:20,207 a mouthful of withered grass. 300 00:40:23,960 --> 00:40:28,568 And where the bison have dug, the fox now spots an opportunity. 301 00:40:37,520 --> 00:40:39,602 Every footstep counts, 302 00:40:42,560 --> 00:40:44,210 but he mustn't break through... 303 00:40:45,200 --> 00:40:46,201 Yet. 304 00:40:49,480 --> 00:40:52,882 He listens carefully to pinpoint his target. 305 00:40:57,480 --> 00:40:58,527 (PATTERING) 306 00:40:58,600 --> 00:40:59,601 It's moving. 307 00:41:17,760 --> 00:41:18,761 (SQUEAKS) 308 00:41:21,280 --> 00:41:22,281 A vole. 309 00:41:24,840 --> 00:41:30,210 Small, but 100 times more nutritious than a mouthful of dried grass. 310 00:41:36,920 --> 00:41:42,882 To get through the winter on these prairies, sometimes brain beats brawn. 311 00:41:49,600 --> 00:41:55,084 Ultimately, life on all grasslands depends on the turn of the seasons. 312 00:42:07,880 --> 00:42:08,881 (CRACKING) 313 00:42:20,720 --> 00:42:24,202 Five hundred miles further north than any tree can survive, 314 00:42:24,280 --> 00:42:26,886 grass returns to life. 315 00:42:35,680 --> 00:42:36,681 (CALLS) 316 00:42:37,680 --> 00:42:40,889 Caribou females have journeyed to the far north 317 00:42:41,640 --> 00:42:42,766 to calve. 318 00:42:43,240 --> 00:42:44,321 (CALLS) 319 00:42:46,600 --> 00:42:51,401 Over 70,000 caribou babies will be born in the next few days. 320 00:42:56,240 --> 00:43:01,087 As the calves appear, so too do the leaves of the newly sprouting grass. 321 00:43:04,600 --> 00:43:06,602 And the calves must strengthen quickly. 322 00:43:07,000 --> 00:43:10,243 Within days they will have to keep up with their parents 323 00:43:10,360 --> 00:43:12,328 on a never-ending march. 324 00:43:17,320 --> 00:43:22,360 At one day old, they're already faster than an Olympic sprinter. 325 00:43:23,480 --> 00:43:27,485 They're testing the legs that will carry them thousands of miles, 326 00:43:29,000 --> 00:43:31,287 better to learn their limitations now. 327 00:43:39,400 --> 00:43:40,526 (CALLS) 328 00:43:45,680 --> 00:43:47,808 (CARIBOU GRUNTING) 329 00:43:51,200 --> 00:43:55,330 It may look playful, but there's no harder life on the grasslands 330 00:43:55,400 --> 00:43:58,051 than that facing these infants. 331 00:44:01,440 --> 00:44:03,681 The caribou mothers now join together, 332 00:44:03,760 --> 00:44:06,843 each with an infant exactly the same age. 333 00:44:15,400 --> 00:44:20,531 They're setting off on the greatest overland trek made by any animal. 334 00:44:43,680 --> 00:44:48,846 But wherever grass eaters travel, predators lie in wait. 335 00:44:50,560 --> 00:44:51,607 (CARIBOU CALLING) 336 00:44:55,640 --> 00:44:59,531 Here they are, Arctic wolves. 337 00:45:06,640 --> 00:45:08,244 They must seize their chance 338 00:45:08,320 --> 00:45:10,800 while the caribou pass through their territory. 339 00:45:43,920 --> 00:45:45,126 (PANTING) 340 00:45:46,920 --> 00:45:51,528 The wolf runs at the herd, trying to flush out the weak or the slow. 341 00:46:00,920 --> 00:46:02,604 A calf is separated. 342 00:46:10,960 --> 00:46:15,682 At full tilt, 40 miles an hour, the wolf is just faster. 343 00:46:24,000 --> 00:46:26,480 But the calf has stamina. 344 00:46:56,080 --> 00:47:01,484 Only a few weeks old, and this calf's will to survive is remarkable. 345 00:47:06,800 --> 00:47:08,643 And it needs to be, 346 00:47:09,080 --> 00:47:12,050 for these young caribou have now started a journey 347 00:47:12,320 --> 00:47:14,163 that will last a lifetime. 348 00:47:17,480 --> 00:47:22,281 Forever chasing the seasonal growth of the grass on which they depend. 349 00:47:31,360 --> 00:47:34,569 Like all grassland creatures, they are at the mercy 350 00:47:34,640 --> 00:47:39,089 of these unpredictable but ultimately bountiful lands. 351 00:47:45,200 --> 00:47:49,171 Grass can survive some of the harshest conditions on Earth, 352 00:47:49,240 --> 00:47:53,529 flood, fire and frost, and still flourish. 353 00:48:03,760 --> 00:48:07,162 So it is that grasslands provide a stage 354 00:48:07,440 --> 00:48:11,126 for the greatest gatherings of wildlife on planet Earth. 355 00:48:25,760 --> 00:48:29,481 For the grasslands team, no location would prove as challenging 356 00:48:29,600 --> 00:48:33,241 as that dominated by elephant grass in northeast India. 357 00:48:34,640 --> 00:48:39,680 The aim, to capture intimate images of some the world's most elusive creatures 358 00:48:40,120 --> 00:48:42,327 using the latest technology. 359 00:48:49,480 --> 00:48:51,403 But they will need to be careful. 360 00:48:53,840 --> 00:48:54,841 (COCKS GUN) 361 00:48:55,760 --> 00:48:56,761 (ELEPHANT TRUMPETS) 362 00:48:56,880 --> 00:49:00,089 More people are killed by wildlife here in Kaziranga 363 00:49:02,520 --> 00:49:05,490 than in any other national park on the planet. 364 00:49:07,560 --> 00:49:09,369 Every time we go into these tunnels, 365 00:49:10,040 --> 00:49:11,724 we have to take an armed guard, 366 00:49:12,360 --> 00:49:14,886 'cause there are so many animals in here that are dangerous. 367 00:49:14,960 --> 00:49:17,122 Tigers are probably the least of our worries, 368 00:49:17,440 --> 00:49:19,169 but rhinos and buffalo, 369 00:49:19,560 --> 00:49:21,961 elephants, sloth bear, all of them can injure you. 370 00:49:22,160 --> 00:49:24,242 And we gotta keep up with our armed guard. 371 00:49:30,240 --> 00:49:32,561 ATTENBOROUGH: The team have bumped into their first obstacle. 372 00:49:34,280 --> 00:49:35,770 SANDESH: There's a rhino right there. 373 00:49:38,960 --> 00:49:43,249 Let's go back because it's too risky going through this heavy grass. 374 00:49:45,640 --> 00:49:46,971 Let's get in the open. 375 00:49:48,360 --> 00:49:50,203 - (SPEAKING LOCAL LANGUAGE) - There's another rhino. 376 00:49:52,000 --> 00:49:54,207 - Now we have two rhinos. - Let's get in here. 377 00:49:56,560 --> 00:49:57,561 Okay. 378 00:49:58,280 --> 00:50:01,523 ATTENBOROUGH: The guard throws a ball of mud to one side of the rhinos, 379 00:50:01,760 --> 00:50:04,331 moving the animals on without harming them. 380 00:50:05,320 --> 00:50:06,651 (SHOUTS) 381 00:50:12,400 --> 00:50:14,402 - We're okay. It's gone. - Okay. 382 00:50:14,760 --> 00:50:16,091 What about the other one? 383 00:50:16,320 --> 00:50:17,481 Let's go, quick. 384 00:50:22,000 --> 00:50:24,571 ATTENBOROUGH: With the rhinos now a safe distance away, 385 00:50:24,640 --> 00:50:28,565 the crew focus on the best spots to position their camera traps. 386 00:50:29,080 --> 00:50:30,809 I love that tunnel, the effect. 387 00:50:34,920 --> 00:50:38,322 ATTENBOROUGH: Over 100 scaffold poles provide the anchor points 388 00:50:38,400 --> 00:50:40,289 for these secret cameras. 389 00:50:41,280 --> 00:50:43,647 When an animal triggers an infrared beam, 390 00:50:43,720 --> 00:50:46,963 the cameras will switch on automatically and start recording. 391 00:50:48,240 --> 00:50:52,802 If it works, the remote-control cameras should capture close-up footage 392 00:50:52,960 --> 00:50:56,282 without disturbing the animals or putting the crew at risk. 393 00:50:57,680 --> 00:51:00,763 Basically, that's about as much like grass as we can make it look. 394 00:51:00,840 --> 00:51:01,841 (CRICKETS CHIRP) 395 00:51:02,680 --> 00:51:06,082 ATTENBOROUGH: As night falls, the crew head back to base for safety. 396 00:51:08,200 --> 00:51:11,921 It's time for the new technology to prove its worth. 397 00:51:17,840 --> 00:51:22,448 At dawn, the crew have a whodunnit mystery on their hands. 398 00:51:22,640 --> 00:51:24,290 CHADDEN: Oh, wow. 399 00:51:25,080 --> 00:51:26,286 That's carnage! 400 00:51:27,680 --> 00:51:29,444 This looks like elephant, we think? 401 00:51:30,840 --> 00:51:32,683 This is scaffold pole 402 00:51:34,080 --> 00:51:36,560 they have bent. Look at that. (CHUCKLES) 403 00:51:39,920 --> 00:51:42,605 It's a sad day. You win some, you lose some. 404 00:51:43,160 --> 00:51:45,606 And this time, the animals have outsmarted us. 405 00:51:46,640 --> 00:51:48,768 In fact, check this out. (CHUCKLES) 406 00:51:49,280 --> 00:51:50,327 Whoo-hoo. 407 00:51:50,400 --> 00:51:55,042 So this is our little army of guards, protecting our trigger box. 408 00:51:55,640 --> 00:51:58,450 Do they bite? These ones, they bite? 409 00:51:59,000 --> 00:52:00,047 Sting? 410 00:52:00,120 --> 00:52:01,963 Whoa! Argh! Ow! 411 00:52:02,640 --> 00:52:04,768 The little (BLEEP). 412 00:52:08,360 --> 00:52:10,522 ATTENBOROUGH: While Chadden irons out the bugs, 413 00:52:11,480 --> 00:52:14,324 Sandesh has met some grumpy locals. 414 00:52:18,080 --> 00:52:21,641 Wild Asian water buffalo have extraordinary senses. 415 00:52:24,160 --> 00:52:26,686 Mothers will charge if they feel threatened. 416 00:52:29,560 --> 00:52:33,042 The guard carries a gun, in case a warning shot is needed, 417 00:52:33,200 --> 00:52:34,611 and with good reason. 418 00:52:37,360 --> 00:52:42,685 More people are killed by buffalo than by any other animal in Kaziranga. 419 00:52:44,320 --> 00:52:45,401 (GRUNTS) 420 00:52:48,160 --> 00:52:49,685 (SHOUTS) 421 00:52:49,760 --> 00:52:51,489 That'll wake you up in the morning. 422 00:52:52,200 --> 00:52:55,682 ATTENBOROUGH: Many of the park staff have cautionary tales about buffalo. 423 00:52:56,160 --> 00:52:59,084 (SPEAKING HINDI) 424 00:53:00,080 --> 00:53:03,641 The buffalo caught him here, through his throat 425 00:53:04,320 --> 00:53:07,210 and the horn came out through his mouth 426 00:53:07,720 --> 00:53:10,246 and flung him before running away. 427 00:53:10,320 --> 00:53:12,800 It's a miracle that he's still alive. 428 00:53:15,000 --> 00:53:17,526 ATTENBOROUGH: If the wildlife is unfriendly to humans, 429 00:53:18,760 --> 00:53:21,730 it's proving downright hostile to camera traps. 430 00:53:22,120 --> 00:53:25,442 CHADDEN: Completely ripped out the scaffold poles, 431 00:53:26,240 --> 00:53:29,244 they've torn the triggers. 432 00:53:30,440 --> 00:53:32,602 ATTENBOROUGH: While Chadden is convinced it's elephants, 433 00:53:32,680 --> 00:53:34,523 the rest of the crew are not so sure. 434 00:53:34,600 --> 00:53:36,011 SANDESH: This is huge! 435 00:53:36,640 --> 00:53:38,369 It's almost like a human footprint. 436 00:53:38,800 --> 00:53:41,804 You can see the front paw, the rear paw. 437 00:53:41,960 --> 00:53:46,329 CHADDEN: We are now two weeks in and it's very frustrating. 438 00:53:46,560 --> 00:53:49,166 I've never actually been anywhere where the animals 439 00:53:49,880 --> 00:53:52,565 go after your equipment and destroy it, more than here. 440 00:53:53,680 --> 00:53:56,843 ATTENBOROUGH: It's time for the team to do some detective work. 441 00:53:58,800 --> 00:54:01,644 Here is our little security camera. 442 00:54:01,720 --> 00:54:04,929 If any animals are coming through and vandalising our main cameras, 443 00:54:05,640 --> 00:54:09,087 we hope that they're being caught on these little things. 444 00:54:12,120 --> 00:54:14,566 ATTENBOROUGH: As the crew up their spying efforts, 445 00:54:14,640 --> 00:54:17,041 the guards take them to a promising lead. 446 00:54:18,080 --> 00:54:21,289 Nothing attracts tigers like a rhino carcass. 447 00:54:21,960 --> 00:54:24,884 It's very fresh. It's like from the morning. 448 00:54:25,240 --> 00:54:27,129 And it looks like there's a tiger cub, 449 00:54:28,120 --> 00:54:32,967 so it should be a tigress with cubs, coming to feed on this rhino carcass. 450 00:54:33,240 --> 00:54:34,321 It's pretty cool. 451 00:54:35,760 --> 00:54:39,401 ATTENBOROUGH: Chadden decides to give the camera traps one last chance. 452 00:54:40,080 --> 00:54:44,847 If there are tigers around, they might scare away the mystery vandals. 453 00:54:46,360 --> 00:54:47,646 Elsewhere in the park, 454 00:54:47,720 --> 00:54:51,361 the security cameras are turning up some unexpected results. 455 00:54:51,840 --> 00:54:55,401 At nighttime, survived another... Ooh! 456 00:54:56,080 --> 00:54:57,206 It's a bear. 457 00:54:58,200 --> 00:54:59,929 Wow, that's a very rare sighting. 458 00:55:00,080 --> 00:55:01,764 SANDESH: I've never seen a bear in Kaziranga. 459 00:55:01,840 --> 00:55:03,410 In all my years, never. 460 00:55:04,800 --> 00:55:08,646 - Oh, his fingernails... - Look at his claws, right on the lens. 461 00:55:09,640 --> 00:55:11,802 CHADDEN: So I thought this was elephant damage. 462 00:55:12,800 --> 00:55:15,883 I never thought we'd see a sloth bear doing that. 463 00:55:16,720 --> 00:55:17,767 That's amazing. 464 00:55:21,840 --> 00:55:26,084 ATTENBOROUGH: A return to the rhino carcass and the plot thickens. 465 00:55:27,440 --> 00:55:28,771 SANDESH: Our transmitter's gone. 466 00:55:29,640 --> 00:55:31,005 CHADDEN: That's what tigers think of camera traps. 467 00:55:31,080 --> 00:55:33,003 CREW MEMBER: Do you think there's a bit over there? 468 00:55:33,160 --> 00:55:34,161 Pieces. 469 00:55:34,600 --> 00:55:38,127 ATTENBOROUGH: The security cameras have caught a new culprit. 470 00:55:38,240 --> 00:55:40,129 CHADDEN: Oh, my goodness, there they are. 471 00:55:40,200 --> 00:55:41,201 SANDESH: Ooh! 472 00:55:41,320 --> 00:55:43,607 There it's a tigress, see that. It's a tigress. 473 00:55:43,680 --> 00:55:45,887 It snarled at the camera trap, look at that. 474 00:55:45,960 --> 00:55:47,485 Sure don't like camera traps. 475 00:55:48,240 --> 00:55:49,241 Okay. 476 00:55:50,640 --> 00:55:52,768 ATTENBOROUGH: With the technology struggling, 477 00:55:52,840 --> 00:55:56,447 Sandesh decides to put himself on the frontline. 478 00:55:56,520 --> 00:55:58,284 CHADDEN: It's on. SANDESH: And now we're ready. 479 00:55:59,160 --> 00:56:00,491 Time to get the tiger. 480 00:56:02,120 --> 00:56:05,647 ATTENBOROUGH: He'll have no protection apart from a thin wall of grass, 481 00:56:05,960 --> 00:56:09,646 and must hope he's as well-hidden as the local wildlife. 482 00:56:11,840 --> 00:56:15,083 Over the next five days, Sandesh plays the role 483 00:56:15,160 --> 00:56:16,810 of human camera trap. 484 00:56:18,680 --> 00:56:19,806 (BIRDS CAWING) 485 00:56:19,880 --> 00:56:23,771 Eventually, the more hands-on approach pays off. 486 00:56:50,120 --> 00:56:53,329 Traditional filming methods and a little bit of patience, 487 00:56:53,520 --> 00:56:57,320 have helped reveal the hidden creatures of Kaziranga. 488 00:57:02,240 --> 00:57:03,241 (GRUNTS) 489 00:57:03,360 --> 00:57:06,330 But it's good to know there are still wild places 490 00:57:06,440 --> 00:57:09,489 where animals like to keep their secrets. 491 00:57:13,160 --> 00:57:14,446 (CREAKING) 492 00:57:15,760 --> 00:57:17,125 CHADDEN: I knew it was elephants. 493 00:57:20,160 --> 00:57:21,286 ATTENBOROUGH: Next time, 494 00:57:22,640 --> 00:57:25,371 we venture to the newest habitat on Earth, 495 00:57:26,040 --> 00:57:27,565 our cities. 496 00:57:28,360 --> 00:57:31,250 To reveal the extraordinary ways 497 00:57:31,960 --> 00:57:35,282 that animals survive in this man-made world. 498 00:57:40,160 --> 00:57:42,162 (THEME MUSIC PLAYING)