1 00:00:00,534 --> 00:00:03,604 It's the greatest wildlife spectacle on earth. 2 00:00:03,604 --> 00:00:07,241 Jean du Plessis follows the wildebeest migration through 3 00:00:07,241 --> 00:00:08,542 the Serengeti 4 00:00:08,542 --> 00:00:09,843 . So there's a birth about to happen just right here 5 00:00:09,843 --> 00:00:11,245 in this group. 6 00:00:11,245 --> 00:00:13,280 . The wildebeests have given birth. 7 00:00:13,280 --> 00:00:16,817 Now they head back North to face the crossing of the treacherous 8 00:00:16,817 --> 00:00:18,085 Mara River. 9 00:00:18,085 --> 00:00:22,689 There's a huge crocodile in the river. A croc of this size only 10 00:00:22,689 --> 00:00:26,293 needs one decent meal once a year. 11 00:00:26,293 --> 00:00:29,263 . Jean aims to time his arrival perfectly 12 00:00:29,263 --> 00:00:31,365 There's another very large group that's also 13 00:00:31,365 --> 00:00:33,300 pushing onto the river. 14 00:00:33,300 --> 00:00:36,403 . But when and where they'll cross is anyone's guess. 15 00:00:36,403 --> 00:00:41,208 There are no timetables for these nomads of the Serengeti. 16 00:00:41,208 --> 00:00:51,251 ♪ 17 00:00:51,251 --> 00:01:11,271 ♪ 18 00:01:11,271 --> 00:01:18,445 ♪ 19 00:01:18,445 --> 00:01:21,348 The Serengeti is one of the oldest intact ecosystems 20 00:01:21,348 --> 00:01:22,516 on earth. 21 00:01:22,516 --> 00:01:27,220 It covers an area nearly the size of Belgium, and spans two 22 00:01:27,220 --> 00:01:32,259 countries - Tanzania in the South and Kenya in the North. 23 00:01:32,259 --> 00:01:36,263 The ecosystem has evolved over millions of years. 24 00:01:36,263 --> 00:01:40,934 Every living thing here - from the tiniest insect to the 25 00:01:40,934 --> 00:01:44,371 largest creature - plays a very specific part in keeping 26 00:01:44,371 --> 00:01:50,377 it balanced. 27 00:01:50,377 --> 00:01:52,646 The most important driver of this system is the 28 00:01:52,646 --> 00:01:54,715 wildebeest migration. 29 00:01:54,715 --> 00:01:57,784 And the mechanism that triggers them to move is 30 00:01:57,784 --> 00:02:00,420 the weather. 31 00:02:00,420 --> 00:02:04,925 Sometime around October, thunder clouds build on the horizon, 32 00:02:04,925 --> 00:02:08,795 and the rains begin to move South - signaling the start of 33 00:02:08,795 --> 00:02:11,465 one of the greatest mass movements of animals on 34 00:02:11,465 --> 00:02:15,402 the planet. 35 00:02:15,402 --> 00:02:19,840 It begins with the actions of a single animal. 36 00:02:19,840 --> 00:02:22,309 Then driven by an ancient instinct, 37 00:02:22,309 --> 00:02:26,613 the rest of the herd follows. 38 00:02:26,613 --> 00:02:29,750 It's a dangerous journey, where predators wait along the route 39 00:02:29,750 --> 00:02:33,553 and prey on the passing herds. 40 00:02:33,553 --> 00:02:36,757 And then there's the treacherous crossing of the Mara River 41 00:02:36,757 --> 00:02:42,763 where wildebeest will die in the thousands. 42 00:02:42,763 --> 00:02:46,400 Wildlife expert and safari guide Jean du Plessis has been 43 00:02:46,400 --> 00:02:48,535 tracking the herds. 44 00:02:48,535 --> 00:02:51,405 The wildebeest have completed the first trek of their 45 00:02:51,405 --> 00:02:53,540 year long journey. 46 00:02:53,540 --> 00:02:57,010 They've arrived on the short grass plains where the females 47 00:02:57,010 --> 00:03:01,014 have begun to give birth in what is the largest mass birth of 48 00:03:01,014 --> 00:03:02,849 mammals on the planet. 49 00:03:02,849 --> 00:03:05,585 We just passed a female with legs sticking out of her. 50 00:03:05,585 --> 00:03:13,293 So there's a birth about to happen. 51 00:03:13,293 --> 00:03:16,430 She found a flat patch and she's just kind of circling around. 52 00:03:16,430 --> 00:03:20,467 She's chosen the safety of the herd to give birth for 53 00:03:20,467 --> 00:03:21,668 obvious reasons. 54 00:03:21,668 --> 00:03:25,005 Hyenas, lions and all kinds of predators are out on the prowl 55 00:03:25,005 --> 00:03:29,609 this time of the morning and they are keeping a watchful eye 56 00:03:29,609 --> 00:03:36,850 out for something just like this. 57 00:03:36,850 --> 00:03:42,322 Yeah, it's going to happen any moment now. 58 00:03:42,322 --> 00:03:42,889 There you go, 59 00:03:42,889 --> 00:03:44,057 she just stood back up. 60 00:03:44,057 --> 00:03:47,627 That's like having gravity help her - but then there the 61 00:03:47,627 --> 00:03:51,598 baby drops! 62 00:03:51,598 --> 00:03:52,699 It's incredible. 63 00:03:52,699 --> 00:03:55,469 She's just coming round sniffing on the baby now. 64 00:03:55,469 --> 00:04:01,808 It's amazing how quickly this all happens. 65 00:04:01,808 --> 00:04:05,545 It's about five to ten minutes now and the baby is starting to 66 00:04:05,545 --> 00:04:07,314 move around a bit more. 67 00:04:07,314 --> 00:04:11,551 It's kind of trying to stand up pushing off with it's hind legs 68 00:04:11,551 --> 00:04:15,455 but very off balance still. 69 00:04:15,455 --> 00:04:25,499 This young guy will be ready to go in the next five minutes. 70 00:04:25,499 --> 00:04:31,938 This young guy will be ready to go in the next five minutes. 71 00:04:31,938 --> 00:04:32,806 There you go. 72 00:04:32,806 --> 00:04:35,475 The new generation starting all over. 73 00:04:35,475 --> 00:04:38,011 In a few months time this baby would even be strong enough to 74 00:04:38,011 --> 00:04:42,349 start up the migration up North and by July - August, 75 00:04:42,349 --> 00:04:44,417 even cross the Mara River. 76 00:04:44,417 --> 00:04:47,120 It's incredible to think that that little thing just born 77 00:04:47,120 --> 00:04:50,123 there so, so helpless... 78 00:04:50,123 --> 00:04:54,427 in six months time will be crossing huge rivers full of 79 00:04:54,427 --> 00:04:58,064 crocodiles that are 12-13 feet long. 80 00:04:58,064 --> 00:05:01,601 You know, and besides that of course they also have to travel 81 00:05:01,601 --> 00:05:05,438 250 miles to get there through hyena and 82 00:05:05,438 --> 00:05:09,843 lion infested savannah. 83 00:05:09,843 --> 00:05:13,980 Less than 10 minutes after 's born the baby is on it's 84 00:05:09,843 --> 00:05:13,980 feet. 85 00:05:13,980 --> 00:05:16,850 This is where the baby will imprint on it's mother. 86 00:05:16,850 --> 00:05:21,721 They will get to know one another's scent and call. 87 00:05:21,721 --> 00:05:24,991 This is just the start of the wildebeest's mass births 88 00:05:24,991 --> 00:05:28,895 200,000 calves will be born over the coming weeks. It's an 89 00:05:28,895 --> 00:05:32,499 extremely smart adaptive strategy. 90 00:05:32,499 --> 00:05:36,136 On these open plains the newborns are easy prey to the 91 00:05:36,136 --> 00:05:38,872 predators that follow the migration. 92 00:05:38,872 --> 00:05:42,742 So by flooding the market with so many newborns at once tilts 93 00:05:42,742 --> 00:05:45,679 the odds in the wildebeests favor. 94 00:05:45,679 --> 00:05:52,419 Some will be taken, but many more will survive. 95 00:05:52,419 --> 00:05:55,755 There are huge challenges ahead for the newborn wildebeests. 96 00:05:55,755 --> 00:05:58,491 In two months time, the calves will be ready to join their 97 00:05:58,491 --> 00:06:01,161 mothers on the return trip up North. 98 00:06:01,161 --> 00:06:09,569 But this first 24 hours is crucial for it's survival. 99 00:06:09,569 --> 00:06:11,605 But with so many newborns today, 100 00:06:11,605 --> 00:06:16,109 the first day is a trying time. 101 00:06:16,109 --> 00:06:18,745 . This is a little water hole outside of camp and this is 102 00:06:18,745 --> 00:06:21,681 some of the only standing water in the area. 103 00:06:21,681 --> 00:06:24,517 And these animals found it. 104 00:06:24,517 --> 00:06:24,985 Yeah. 105 00:06:24,985 --> 00:06:27,654 Great delight. 106 00:06:27,654 --> 00:06:29,222 There's a bit of a disturbance. 107 00:06:29,222 --> 00:06:31,958 For many of these young wildebeest that were born this 108 00:06:31,958 --> 00:06:35,662 morning or last night, this will be the first time that they are 109 00:06:35,662 --> 00:06:39,532 drinking and there's a little bit of pandemonium as the 110 00:06:39,532 --> 00:06:42,469 wildebeest start to run around and they lose their mothers. 111 00:06:42,469 --> 00:06:47,007 And there's a fear of them just standing around. 112 00:06:47,007 --> 00:06:51,478 There's one here in the grass that clearly lost it's mom, 113 00:06:51,478 --> 00:06:54,848 and a few of the adult females have been coming around just 114 00:06:54,848 --> 00:06:58,118 smelling it and showing a little bit of concern. 115 00:06:58,118 --> 00:06:59,919 The poor thing must've been born this morning, 116 00:06:59,919 --> 00:07:05,125 early, and to already lose your mom... 117 00:07:05,125 --> 00:07:06,259 There's some interest. 118 00:07:06,259 --> 00:07:07,761 And there's a second baby that's also coming up now, 119 00:07:07,761 --> 00:07:09,696 even younger. 120 00:07:09,696 --> 00:07:11,264 That one is tiny. 121 00:07:11,264 --> 00:07:18,905 You can still see the umbilical cord hanging down. 122 00:07:18,905 --> 00:07:20,974 You can see there's a few mothers coming up smelling 123 00:07:20,974 --> 00:07:23,143 some of these lost babies. 124 00:07:23,143 --> 00:07:25,979 And they will immediately push them away once they realize 125 00:07:25,979 --> 00:07:27,881 that's not their calf. 126 00:07:27,881 --> 00:07:31,518 Wildebeests are very much like bats or flamingos where every 127 00:07:31,518 --> 00:07:35,922 calf has a particular frequency that the mother zones in on. 128 00:07:35,922 --> 00:07:43,096 And it's not uncommon for babies to get lost but they generally 129 00:07:43,096 --> 00:07:49,669 find each other. 130 00:07:49,669 --> 00:07:52,706 . Luckily for this calf, it's mother responds to it's cries 131 00:07:52,706 --> 00:07:56,009 and the two are reunited. 132 00:07:56,009 --> 00:08:06,886 The pair head off with the baby sticking closer by this time. 133 00:08:06,886 --> 00:08:09,289 Wildlife expert and safari Guide Jean du Plessis, 134 00:08:09,289 --> 00:08:12,258 is in the central Serengeti following the year long 135 00:08:12,258 --> 00:08:15,195 wildebeest migration. 136 00:08:15,195 --> 00:08:20,333 It's February - the midway point on the migration route. 137 00:08:20,333 --> 00:08:23,269 Jean is on the short grass plains in the South observing 138 00:08:23,269 --> 00:08:26,940 the mass births - the wildebeest females all give 139 00:08:26,940 --> 00:08:29,309 birth at the same time. 140 00:08:29,309 --> 00:08:32,145 Hundreds of thousands of calves are born in a two to 141 00:08:32,145 --> 00:08:33,980 three week period. 142 00:08:33,980 --> 00:08:37,317 For a species constantly on the move, this is an 143 00:08:37,317 --> 00:08:41,020 excellent survival strategy. 144 00:08:41,020 --> 00:08:42,288 The newborns are vulnerable 145 00:08:42,288 --> 00:08:45,291 to the predators that follow the migration. 146 00:08:45,291 --> 00:08:47,927 The only safety is in numbers. 147 00:08:47,927 --> 00:08:50,663 So the female wildebeests have timed their births 148 00:08:50,663 --> 00:08:52,332 to flood the market. 149 00:08:52,332 --> 00:08:55,735 Some will fall to predators, but with so many young, 150 00:08:55,735 --> 00:08:59,672 the odds are in the wildebeests favor. 151 00:08:59,672 --> 00:09:02,742 For the newborns, life starts quickly. 152 00:09:02,742 --> 00:09:04,844 The calves are up and running within ten minutes 153 00:09:04,844 --> 00:09:07,280 of being born. 154 00:09:07,280 --> 00:09:11,050 The first 24 hours is crucial for these newborns. 155 00:09:11,050 --> 00:09:13,787 This is when they bond with their mothers. 156 00:09:13,787 --> 00:09:18,291 But in a massive herd, the little ones often get lost. 157 00:09:18,291 --> 00:09:23,863 Jean has found a calf wandering along a main road - alone. 158 00:09:23,863 --> 00:09:25,698 . I just came across a baby wildebeest 159 00:09:25,698 --> 00:09:26,900 that's obviously lost. 160 00:09:26,900 --> 00:09:31,104 And what happens is they, they basically imprint on anything. 161 00:09:31,104 --> 00:09:34,374 So it saw this vehicle driving fairly close to him and came 162 00:09:34,374 --> 00:09:36,109 running up to it. 163 00:09:36,109 --> 00:09:41,080 And at this stage of their lives they're so dependent on a bigger 164 00:09:41,080 --> 00:09:44,951 creature taking care of them, that um, 165 00:09:44,951 --> 00:09:50,023 even if I got out of the car it will come right up to me and 166 00:09:50,023 --> 00:09:51,891 hope for some care. 167 00:09:51,891 --> 00:09:55,962 It's quite sad. 168 00:09:55,962 --> 00:09:59,866 . The baby heads off over the plains in search of it's mother. 169 00:09:59,866 --> 00:10:02,302 Luckily, it chooses the direction that takes it back to 170 00:10:02,302 --> 00:10:05,138 the protection of the herd. 171 00:10:05,138 --> 00:10:08,441 And that's a good thing, Just up the road, 172 00:10:08,441 --> 00:10:11,110 Jean finds a predator. 173 00:10:11,110 --> 00:10:13,279 I just came upon a cheetah, 174 00:10:13,279 --> 00:10:15,415 she's down in a crouching position. 175 00:10:15,415 --> 00:10:17,217 It looks to me like she's hunting. 176 00:10:17,217 --> 00:10:21,888 She's looking at wildebeests; there's quite a few of them 177 00:10:21,888 --> 00:10:25,792 around, but there's also like 4 or 5 Thompson's gazelles here 178 00:10:25,792 --> 00:10:28,027 that she's more than likely after. 179 00:10:28,027 --> 00:10:30,964 It also seems like these Thompson's gazelles are moving 180 00:10:30,964 --> 00:10:33,900 towards her, but also still not looking at her. 181 00:10:33,900 --> 00:10:34,234 There she goes! 182 00:10:34,234 --> 00:10:44,277 ♪ 183 00:10:44,277 --> 00:10:53,019 ♪ 184 00:10:53,019 --> 00:10:55,722 I think she couldn't make up her mind which one to go after, 185 00:10:55,722 --> 00:10:59,759 and it's so important for cheetahs to focus on one gazelle 186 00:10:59,759 --> 00:11:01,394 and just stick behind that. 187 00:11:01,394 --> 00:11:04,797 It seemed like she was going between two different groups and 188 00:11:04,797 --> 00:11:10,169 she didn't get lucky on this one. 189 00:11:10,169 --> 00:11:13,473 . The cheetah has missed it's prey. 190 00:11:13,473 --> 00:11:15,975 It's too hot now for another attempt, 191 00:11:15,975 --> 00:11:21,447 so it retreats and will look for any shade it can find. 192 00:11:21,447 --> 00:11:24,317 She's now walking back to her cubs, 193 00:11:24,317 --> 00:11:27,020 which seems to be the only shade in the area. 194 00:11:27,020 --> 00:11:29,355 It's actually a safari vehicle, that's parked behind us - 195 00:11:29,355 --> 00:11:33,059 who is also witnessing this, and the cubs are lying under their 196 00:11:33,059 --> 00:11:38,498 vehicle and she is on her way there as well. 197 00:11:38,498 --> 00:11:40,133 . There's no lunch for them. 198 00:11:40,133 --> 00:11:42,902 But the cubs seem fine with that. 199 00:11:42,902 --> 00:11:48,408 Now they have more time to play. 200 00:11:48,408 --> 00:11:51,544 . So the mom just came to this vehicle to join her cubs. 201 00:11:51,544 --> 00:11:57,550 This is the only shade around and they need to improvise and 202 00:11:57,550 --> 00:12:01,988 they are really having a good time lying under the vehicle. 203 00:12:01,988 --> 00:12:04,257 There's three cubs here. 204 00:12:04,257 --> 00:12:06,426 Extremely playful... 205 00:12:06,426 --> 00:12:10,196 and obviously enjoying the new tires on this vehicle and giving 206 00:12:10,196 --> 00:12:15,401 it a good chew. 207 00:12:15,401 --> 00:12:17,503 These guys are going to be stuck here for a while. 208 00:12:17,503 --> 00:12:20,540 I'm trying to make sure none of these cubs come and lie down 209 00:12:20,540 --> 00:12:23,810 under our car, cause the moment they get under your car you 210 00:12:23,810 --> 00:12:25,311 ain't going anywhere. 211 00:12:25,311 --> 00:12:27,547 These cheetahs are pretty much down for the rest of the day so 212 00:12:27,547 --> 00:12:31,150 I hope these guys have lunch with them. 213 00:12:31,150 --> 00:12:40,593 Or maybe they will be lunch! (Laughs) 214 00:12:40,593 --> 00:12:43,329 . The tourists will have to put until the cheetahs decide to 215 00:12:43,329 --> 00:12:47,533 move, which will most likely mean a few more hours until the 216 00:12:47,533 --> 00:12:50,103 temperature starts to cool, and the cheetahs 217 00:12:50,103 --> 00:12:57,110 head off to find dinner. 218 00:12:57,110 --> 00:13:00,046 The wildebeest herds will spend the next few months in the short 219 00:13:00,046 --> 00:13:03,049 grass plains, feeding on the rich grasses, 220 00:13:03,049 --> 00:13:08,921 and nurturing their young. 221 00:13:08,921 --> 00:13:12,358 But soon the rains will start moving North signaling the herds 222 00:13:12,358 --> 00:13:18,164 that it's time to get going again. 223 00:13:18,164 --> 00:13:21,034 The wildebeest migration is not just a defining piece of 224 00:13:21,034 --> 00:13:23,436 life on the Serengeti - 225 00:13:23,436 --> 00:13:27,907 It is also a key driver of the ecosystem. 226 00:13:27,907 --> 00:13:30,877 Over the course of the year, the millions of wildebeests 227 00:13:30,877 --> 00:13:33,546 drastically affect the landscape. 228 00:13:33,546 --> 00:13:37,417 The animals graze on the grasses like a giant team of lawnmowers, 229 00:13:37,417 --> 00:13:42,155 allowing new shoots to grow, and keeping the plains healthy. 230 00:13:42,155 --> 00:13:45,892 With millions of wildebeests, there's a lot of waste. 231 00:13:45,892 --> 00:13:49,295 Some of that dung fertilizes the grass, which in turn helps it 232 00:13:49,295 --> 00:13:52,932 to grow for the next time the animals pass. 233 00:13:52,932 --> 00:13:55,902 But there is so much dung - that nature has developed other 234 00:13:55,902 --> 00:14:00,640 solutions to make sure plains are not overwhelmed. 235 00:14:00,640 --> 00:14:09,315 On the Serengeti an army of it's smallest residents go to work. 236 00:14:09,315 --> 00:14:13,953 . We just came upon this great dung beetle making a dung ball 237 00:14:13,953 --> 00:14:16,055 out of some zebra droppings. 238 00:14:16,055 --> 00:14:18,291 It's incredible to actually watch the whole thing happen 239 00:14:18,291 --> 00:14:22,261 from the beginning, where the beetle has almost cut out this 240 00:14:22,261 --> 00:14:27,200 ball and then selecting these really good pieces of dung to 241 00:14:27,200 --> 00:14:29,035 complete the ball. 242 00:14:29,035 --> 00:14:32,438 And it's using these spade- like legs to pat it down 243 00:14:32,438 --> 00:14:35,308 and make it round. 244 00:14:35,308 --> 00:14:39,178 What it's going to do now is it will start to roll it, 245 00:14:39,178 --> 00:14:43,716 and the idea about the rolling is to now cover it in soil, 246 00:14:43,716 --> 00:14:48,087 making a really solid casing that will eventually protect the 247 00:14:48,087 --> 00:14:53,526 egg and then later on the larvae that's going to be inside this 248 00:14:53,526 --> 00:14:55,561 wet pile of dung. 249 00:14:55,561 --> 00:14:56,562 Ah, there we go! 250 00:14:56,562 --> 00:14:57,330 There we go! 251 00:14:57,330 --> 00:14:58,498 Quite amazing. 252 00:14:58,498 --> 00:15:00,399 Look at that. 253 00:15:00,399 --> 00:15:03,536 This thing is like 10 times the size of this dung beetle, 254 00:15:03,536 --> 00:15:07,607 and it's moving it. 255 00:15:07,607 --> 00:15:10,109 It's not only going to move it, it's going to push it quite a 256 00:15:10,109 --> 00:15:12,011 considerable distance. 257 00:15:12,011 --> 00:15:15,414 And the idea about the distance pushing is to cover this wet mud 258 00:15:15,414 --> 00:15:19,652 with this soil. 259 00:15:19,652 --> 00:15:22,555 . Insect life is crucial to the ecosystem, 260 00:15:22,555 --> 00:15:26,058 and true to the Serengeti's epic nature, 261 00:15:26,058 --> 00:15:30,997 even the small creatures do things in big ways. 262 00:15:30,997 --> 00:15:34,100 Scattered throughout Africa are impressive structures built of 263 00:15:34,100 --> 00:15:36,302 mud and clay. 264 00:15:36,302 --> 00:15:38,271 These are termite mounds. 265 00:15:38,271 --> 00:15:42,408 Their architects, although tiny, have a huge role to play. 266 00:15:42,408 --> 00:15:47,079 With 2.5 million mammals in the migration, one would think that 267 00:15:47,079 --> 00:15:51,517 nothing can out-compete them when it comes to the amount of 268 00:15:51,517 --> 00:15:53,286 grass that's consumed. 269 00:15:53,286 --> 00:15:57,023 But the true champions are in fact these little guys. 270 00:15:57,023 --> 00:16:01,661 Within a termite mount there's no sexes. 271 00:16:01,661 --> 00:16:04,497 Theoretically they are all sterile females. 272 00:16:04,497 --> 00:16:10,136 But they are categorized in classes and what I see here are 273 00:16:10,136 --> 00:16:14,173 lots of different individuals doing different functions. 274 00:16:14,173 --> 00:16:15,408 There are some bringing up the mud, 275 00:16:15,408 --> 00:16:18,511 building the mound, and there's others that will be collecting 276 00:16:18,511 --> 00:16:21,814 dead plant materials but then there's these big guys, 277 00:16:21,814 --> 00:16:26,419 the soldiers, who would just be walking around and they're 278 00:16:26,419 --> 00:16:27,653 constantly tapping their heads. 279 00:16:27,653 --> 00:16:30,523 It's like a signal, and I'm sure they're a little bit disturbed 280 00:16:30,523 --> 00:16:33,459 with me being here, and that's a signal that they're giving that 281 00:16:33,459 --> 00:16:35,695 there's something close by. 282 00:16:35,695 --> 00:16:39,732 And their sole purpose will be to defend all these smaller ones 283 00:16:39,732 --> 00:16:43,469 which are completely helpless. 284 00:16:43,469 --> 00:16:46,339 These harvester termites don't actually carry the dead plant 285 00:16:46,339 --> 00:16:48,608 material in their mandibles, but they would swallow it and 286 00:16:48,608 --> 00:16:51,477 regurgitate it when they get back into the mound. 287 00:16:51,477 --> 00:16:54,580 These plants then act as a substrate for fungi to grow in 288 00:16:54,580 --> 00:16:59,685 and that is what these termites eat. 289 00:16:59,685 --> 00:17:02,755 That's also one of the main reasons for these chimneys, 290 00:17:02,755 --> 00:17:06,125 is that it creates an air conditioning system that 291 00:17:06,125 --> 00:17:09,362 maintains a constant temperature within the mound of about 26 - 292 00:17:09,362 --> 00:17:13,733 27 degrees Celsius and it's just a perfect environment for fungi 293 00:17:13,733 --> 00:17:14,967 to grow. 294 00:17:14,967 --> 00:17:17,637 . These harvester termites eat enormous amounts of grass and 295 00:17:17,637 --> 00:17:19,739 plant material. 296 00:17:19,739 --> 00:17:22,575 Their eating habits, and the placement of these mounds 297 00:17:22,575 --> 00:17:25,211 changes soil textures. 298 00:17:25,211 --> 00:17:28,648 . In Africa there is lots of different types of mounds that 299 00:17:28,648 --> 00:17:31,684 one can find and the bulk of the mound goes down, 300 00:17:31,684 --> 00:17:34,220 and if I look down into these chimneys. 301 00:17:34,220 --> 00:17:39,592 it is at least 8 feet down that the actual air vent goes. 302 00:17:39,592 --> 00:17:42,795 Because these termites are not actually living inside the air 303 00:17:42,795 --> 00:17:46,799 vents they have got no problem with other creatures making use 304 00:17:46,799 --> 00:17:49,568 of such a safe environment. 305 00:17:49,568 --> 00:17:53,839 This mount have a hive of African honeybees living inside 306 00:17:53,839 --> 00:17:56,909 here; I can constantly see them coming and going. 307 00:17:56,909 --> 00:17:59,845 But even more interesting is that there's some sort of 308 00:17:59,845 --> 00:18:03,916 predator living in here - a small predator that 309 00:18:03,916 --> 00:18:07,486 predominantly feeds off of something like millipedes, 310 00:18:07,486 --> 00:18:10,556 because I can see a lot of millipede shells lying around. 311 00:18:10,556 --> 00:18:13,392 And there's even a dead bird inside. 312 00:18:13,392 --> 00:18:23,436 It's just such a fantastic entire ecosystem. 313 00:18:23,436 --> 00:18:31,911 It's just such a fantastic entire ecosystem. 314 00:18:31,911 --> 00:18:34,513 . The short grass plains in the South of the Serengeti are 315 00:18:34,513 --> 00:18:36,482 beginning to dry out. 316 00:18:36,482 --> 00:18:37,750 The rains are moving North. 317 00:18:37,750 --> 00:18:43,589 As always, the wildebeest's instinct compels them to follow. 318 00:18:43,589 --> 00:18:45,891 Instinct tells them the rains will lead them to 319 00:18:45,891 --> 00:18:49,462 better grazing land. 320 00:18:49,462 --> 00:18:52,565 The babies have survived their first three months and are 321 00:18:52,565 --> 00:18:54,333 getting stronger. 322 00:18:54,333 --> 00:18:57,269 They need to, because in just two months time, 323 00:18:57,269 --> 00:19:00,239 they will face the greatest challenge of their lives - 324 00:19:00,239 --> 00:19:10,883 their first crossing of the crocodile infested Mara River. 325 00:19:10,883 --> 00:19:14,587 Wildlife expert and Safari Guide Jean du Plessis has been 326 00:19:14,587 --> 00:19:16,922 checking in with the herds at various points on their 327 00:19:16,922 --> 00:19:19,992 annual route. 328 00:19:19,992 --> 00:19:24,563 Along the way he's taking time to explore some of the dynamic 329 00:19:24,563 --> 00:19:28,667 relationships in the Serengeti's ecosystem. 330 00:19:28,667 --> 00:19:32,738 The Serengeti is one of the few unspoiled places on the planet. 331 00:19:32,738 --> 00:19:36,442 This makes it a perfect place to to see how an ecosystem evolves 332 00:19:36,442 --> 00:19:39,745 to support a variety of species. 333 00:19:39,745 --> 00:19:43,382 Everything - from a blade of grass to the predators, 334 00:19:43,382 --> 00:19:46,952 and the giants of Africa, all play their roles, and 335 00:19:46,952 --> 00:19:50,289 they are all inter-connected. 336 00:19:50,289 --> 00:19:53,459 Remove one, and the whole ecosystem can be thrown 337 00:19:53,459 --> 00:19:57,863 out of balance. 338 00:19:57,863 --> 00:20:00,599 The Savannah elephant is a large animal, 339 00:20:00,599 --> 00:20:04,870 and it's impact on this ecosystem is equally large. 340 00:20:04,870 --> 00:20:08,741 Elephants are bulk feeders, and eat a lot of foliage. 341 00:20:08,741 --> 00:20:12,478 So their role in this symbiotic system is to maintain the 342 00:20:12,478 --> 00:20:15,915 Savanna and woodlands by reducing tree density, 343 00:20:15,915 --> 00:20:23,989 and keeping the forest from overrunning the grass plains. 344 00:20:23,989 --> 00:20:26,292 Some species flourish by developing a survival 345 00:20:26,292 --> 00:20:31,330 mechanism that draws some, and repels others. 346 00:20:31,330 --> 00:20:35,401 Trees develop nutritious leaves, or tasty fruit to encourage 347 00:20:35,401 --> 00:20:37,369 animals to eat. 348 00:20:37,369 --> 00:20:40,673 The animals them move on and deposit seeds from the trees in 349 00:20:40,673 --> 00:20:44,944 a new location, in a fresh pile of fertilizer. 350 00:20:44,944 --> 00:20:47,880 But too much of a good thing can be bad for the trees, 351 00:20:47,880 --> 00:20:50,916 so they have also evolved ways of keeping browsers like 352 00:20:50,916 --> 00:20:54,386 elephant and giraffe from eating too much. 353 00:20:54,386 --> 00:20:55,554 This is an acacia tortilis. 354 00:20:55,554 --> 00:20:58,090 This is one of the most common trees in the Serengeti and 355 00:20:58,090 --> 00:21:01,760 what's interesting is that it's also one of the most nutritious 356 00:21:01,760 --> 00:21:03,729 leaves and probably the tree of choice for 357 00:21:03,729 --> 00:21:05,698 something like a giraffe. 358 00:21:05,698 --> 00:21:08,834 In the rest of the world there's over 800 different 359 00:21:08,834 --> 00:21:10,469 species of Acacia. 360 00:21:10,469 --> 00:21:13,739 Most of the Acacia species have not got thorns, 361 00:21:13,739 --> 00:21:18,010 and they're completely evolved in Africa as a form of 362 00:21:18,010 --> 00:21:20,713 protection against these massive browsers, 363 00:21:20,713 --> 00:21:25,718 but still the giraffe managed to find a way to get past these 364 00:21:25,718 --> 00:21:28,587 thorns with the prehensile tongue that can really go 365 00:21:28,587 --> 00:21:31,957 in between these thorns and completely strip 366 00:21:31,957 --> 00:21:35,694 off these little leaves. 367 00:21:35,694 --> 00:21:39,064 Giraffes are highly efficient so they are obviously getting what 368 00:21:39,064 --> 00:21:44,703 they need to live out on these sometimes very barren plains. 369 00:21:44,703 --> 00:21:47,039 Another interesting thing about these acacias are that they've 370 00:21:47,039 --> 00:21:49,875 got these tiny, tiny little leaves, 371 00:21:49,875 --> 00:21:55,981 and the main reason is to allow maximum sun to reach the leaves 372 00:21:55,981 --> 00:21:59,718 but to avoid it losing too much moisture, 373 00:21:59,718 --> 00:22:02,688 making it possible for this tree to survive in such a dry and 374 00:22:02,688 --> 00:22:05,057 arid environment. 375 00:22:05,057 --> 00:22:08,561 . Even something as routine as one species having a bath, 376 00:22:08,561 --> 00:22:12,698 can have benefits for another species in an ecosystem that's 377 00:22:12,698 --> 00:22:17,036 evolved in an interconnected way. 378 00:22:17,036 --> 00:22:20,172 . This is Central Serengeti, where there is water all year round 379 00:22:20,172 --> 00:22:23,142 and we just came upon a nice breeding group of elephants that 380 00:22:23,142 --> 00:22:25,744 came down for their morning drink. 381 00:22:25,744 --> 00:22:30,015 There's huge excitement between some of the adolescents as they 382 00:22:30,015 --> 00:22:33,852 go down into the river and are having a good old swim and a 383 00:22:33,852 --> 00:22:35,087 nice wash. 384 00:22:35,087 --> 00:22:38,958 . In a balanced ecosystem even something as routine as a bath 385 00:22:38,958 --> 00:22:43,162 can have benefits for a number of species. 386 00:22:43,162 --> 00:22:46,632 As the elephants splash and play they widen the wallow, 387 00:22:46,632 --> 00:22:48,968 which means it can hold more water. 388 00:22:48,968 --> 00:22:53,772 It also creates more access so other animals can come to drink. 389 00:22:53,772 --> 00:22:56,842 . There's one elephant that's having a good old scratch. 390 00:22:56,842 --> 00:22:59,044 This is a good ways of getting rid of ticks you know, 391 00:22:59,044 --> 00:23:03,115 with a kind of mud, a little bit of a body paint, 392 00:23:03,115 --> 00:23:07,953 that scratches off all the ticks. 393 00:23:07,953 --> 00:23:13,459 He's coming out now. 394 00:23:13,459 --> 00:23:16,161 It's really important for elephants to get to water on a 395 00:23:16,161 --> 00:23:18,030 fairly regular basis. 396 00:23:18,030 --> 00:23:22,134 Their skins are about double the size as it seems and it's all 397 00:23:22,134 --> 00:23:26,038 kind of wrinkled up, and by rolling around in mud and water 398 00:23:26,038 --> 00:23:30,075 like this, a lot of water gets trapped in these folds and that 399 00:23:30,075 --> 00:23:33,112 will actually keep them cool when they're out on the plains 400 00:23:33,112 --> 00:23:36,915 it's extremely hot during the middle of the day. 401 00:23:36,915 --> 00:23:45,124 We've got a nice female. 402 00:23:45,124 --> 00:23:56,502 Ah, I think she didn't like me calling her a female. 403 00:23:56,502 --> 00:24:01,073 They have the most incredible wash and play and rub, 404 00:24:01,073 --> 00:24:04,977 you know it's like a massive spa that they found here. 405 00:24:04,977 --> 00:24:08,814 This would be a very popular little water hole in such hot 406 00:24:08,814 --> 00:24:17,823 dry climates as right now. 407 00:24:17,823 --> 00:24:21,660 I heard one of these older cows make what we call a "tummy 408 00:24:21,660 --> 00:24:24,730 rumble"; it's one of their communication signals; 409 00:24:24,730 --> 00:24:28,534 and that's generally a sign that they want some kind of movement. 410 00:24:28,534 --> 00:24:32,171 I'm sure one of these two here are probably the matriarch and 411 00:24:32,171 --> 00:24:35,908 she's in charge of this little breeding group and she probably 412 00:24:35,908 --> 00:24:38,911 feels like she had enough now and it's time to move on. 413 00:24:38,911 --> 00:24:43,782 And these younger ones does not seem in the mood 414 00:24:43,782 --> 00:24:48,020 to be moving on. 415 00:24:48,020 --> 00:24:51,090 . As the Central Serengeti enters it's dry season, 416 00:24:51,090 --> 00:24:53,225 and streams and rivers disappear, 417 00:24:53,225 --> 00:24:56,895 these wallows will become refuges for another one of 418 00:24:56,895 --> 00:25:06,271 Africa's great species. 419 00:25:06,271 --> 00:25:09,975 Behind me is the Orange river, and this is one of many seasonal 420 00:25:09,975 --> 00:25:11,777 rivers in the Serengeti. 421 00:25:11,777 --> 00:25:14,580 The catchment area for this river is coming off the short 422 00:25:14,580 --> 00:25:18,050 grass plains and it only feeds into this river 423 00:25:18,050 --> 00:25:20,986 during the rain season. 424 00:25:20,986 --> 00:25:24,757 Right here it's a little bit of a dammed area where obviously 425 00:25:24,757 --> 00:25:27,192 hippos are having a great time. 426 00:25:27,192 --> 00:25:32,030 It's quite a popular tourist stop where one can have easy 427 00:25:32,030 --> 00:25:35,667 access to such great herds of hippos. 428 00:25:35,667 --> 00:25:39,938 Unfortunately for these guys, as it gets dryer and dryer, 429 00:25:39,938 --> 00:25:43,275 all of this water will eventually dry up. 430 00:25:43,275 --> 00:25:46,211 And that can be quite catastrophic for hippos in 431 00:25:46,211 --> 00:25:48,247 extreme dry seasons. 432 00:25:48,247 --> 00:25:53,051 Fortunately hippos do have a little bit of a backup system 433 00:25:53,051 --> 00:25:57,656 that can give them a few more days when it's completely dry. 434 00:25:57,656 --> 00:26:00,993 They release their own type of sunscreen, 435 00:26:00,993 --> 00:26:03,629 that's referred to as "blood sweat" and that will turn a 436 00:26:03,629 --> 00:26:05,664 hippo completely red and give them another two, 437 00:26:05,664 --> 00:26:09,868 three, maybe up to five days to survive hopefully waiting for 438 00:26:09,868 --> 00:26:12,104 rain to arrive. 439 00:26:12,104 --> 00:26:17,776 These hippos can have a bit of a tough time during certain times 440 00:26:17,776 --> 00:26:21,146 of the year which is different to hippos living up in the 441 00:26:21,146 --> 00:26:24,216 Northern Serengeti, living in the Mara river, 442 00:26:24,216 --> 00:26:26,985 that's got a year round supply of water. 443 00:26:26,985 --> 00:26:37,029 ♪ 444 00:26:37,029 --> 00:26:51,076 ♪ 445 00:26:51,076 --> 00:27:01,119 ♪ 446 00:27:01,119 --> 00:27:23,175 ♪ 447 00:27:23,175 --> 00:27:26,211 . It's July in the Serengeti, and the wildebeests have begun 448 00:27:26,211 --> 00:27:29,348 their migration back up North towards Kenya. 449 00:27:29,348 --> 00:27:32,084 The newborns are getting stronger each day. 450 00:27:32,084 --> 00:27:33,952 They'll need that strength. 451 00:27:33,952 --> 00:27:37,189 In a few weeks time - they will face their biggest challenge of 452 00:27:37,189 --> 00:27:42,494 their lives - the crossing of the treacherous Mara River. 453 00:27:42,494 --> 00:27:46,265 Wildlife Expert and Safari guide Jean du Plessis has been 454 00:27:46,265 --> 00:27:48,800 tracking the herds since they began their journey 455 00:27:48,800 --> 00:27:50,135 9 months ago. 456 00:27:50,135 --> 00:27:52,938 So the migration is heading North at the moment, 457 00:27:52,938 --> 00:27:55,941 and it seems like it has split up into two groups. 458 00:27:55,941 --> 00:28:00,379 One group going West, and another group going East. 459 00:28:00,379 --> 00:28:03,749 Now the problem is that the group going East is heading into 460 00:28:03,749 --> 00:28:08,020 the Serengeti wilderness area, that's inaccessible to us, 461 00:28:08,020 --> 00:28:11,490 and the group heading West are heading into private game 462 00:28:11,490 --> 00:28:15,093 reserves where we also cannot go into. 463 00:28:15,093 --> 00:28:20,499 So our only hope is to reconnect with this group as they are 464 00:28:20,499 --> 00:28:24,169 heading into the Northern Serengeti and maybe get together 465 00:28:24,169 --> 00:28:29,408 again and form one of these huge megaherds. 466 00:28:29,408 --> 00:28:32,311 For Jean, the good news is that the wildebeest will be moving 467 00:28:32,311 --> 00:28:35,881 very fast - and for good reason. 468 00:28:35,881 --> 00:28:38,116 They're moving through the woodlands and the wildebeest 469 00:28:38,116 --> 00:28:41,353 feel vulnerable here. 470 00:28:41,353 --> 00:28:45,223 Lions and other predators have lots of cover which gives them a 471 00:28:45,223 --> 00:28:50,996 great advantage when it comes to hunting wildebeest. 472 00:28:50,996 --> 00:28:53,932 The central part of the Serengeti is entering it's 473 00:28:53,932 --> 00:28:55,400 dry season. 474 00:28:55,400 --> 00:28:59,037 As the rains move North, the rivers and streams begin to 475 00:28:59,037 --> 00:29:03,208 recede, leaving only small pockets of water. 476 00:29:03,208 --> 00:29:07,512 This affects different species in different ways. 477 00:29:07,512 --> 00:29:10,449 These small pools of water become gathering places for 478 00:29:10,449 --> 00:29:13,385 animals to drink and cool off. 479 00:29:13,385 --> 00:29:16,822 And that makes it a perfect place for predators like lions, 480 00:29:16,822 --> 00:29:19,358 to find their next meal. 481 00:29:19,358 --> 00:29:23,161 I just drove over a small bridge and there's a male lion lying on 482 00:29:23,161 --> 00:29:24,396 the side of this river. 483 00:29:24,396 --> 00:29:30,936 This is the beginning of the Grumeti river and they've killed 484 00:29:30,936 --> 00:29:35,173 a zebra and have eaten quite a bit - they are really thick. 485 00:29:35,173 --> 00:29:37,542 It seems like he's going to pull this back in the shade. 486 00:29:37,542 --> 00:29:39,511 What probably happened here is that these zebras came down to 487 00:29:39,511 --> 00:29:42,981 drink and these males ambushed them. 488 00:29:42,981 --> 00:29:44,082 It looks like fairly young males, 489 00:29:44,082 --> 00:29:47,386 you know, their manes are not completely full yet, 490 00:29:47,386 --> 00:29:49,621 so it's hard for these males to make a kill. 491 00:29:49,621 --> 00:29:52,924 So there is a perfect place for these males to be lining up, 492 00:29:52,924 --> 00:29:55,327 waiting for these zebras to come down and drink. 493 00:29:55,327 --> 00:29:56,561 And that's more than likely what happened. 494 00:29:56,561 --> 00:30:00,465 And he's trying to kind of pull this back into the shade now, 495 00:30:00,465 --> 00:30:03,135 but it's so hot and you need to decide where 496 00:30:03,135 --> 00:30:06,104 he's going to preserve his energy. 497 00:30:06,104 --> 00:30:08,874 There's actually a big croc on the river as well, 498 00:30:08,874 --> 00:30:10,142 that's eyeing up that carcass; 499 00:30:10,142 --> 00:30:11,176 (Lion roars) 500 00:30:11,176 --> 00:30:12,377 that lion's giving a roar. 501 00:30:12,377 --> 00:30:15,213 and you can see this crocodile opening his mouth and probably 502 00:30:15,213 --> 00:30:16,515 hissing back at the lion. 503 00:30:16,515 --> 00:30:22,287 It's quite amazing seeing something like this. 504 00:30:22,287 --> 00:30:25,557 . Crocodiles have evolved to live in water where they are 505 00:30:25,557 --> 00:30:27,626 fast and agile hunters. 506 00:30:27,626 --> 00:30:31,196 They're not really designed to attack on land. 507 00:30:31,196 --> 00:30:34,599 When the rivers dry up, the crocs lose most of their 508 00:30:34,599 --> 00:30:38,236 predatory advantage, and they have to become scavengers if 509 00:30:38,236 --> 00:30:40,338 they want to eat. 510 00:30:40,338 --> 00:30:42,641 Nothing of this animal will go to waste, 511 00:30:42,641 --> 00:30:45,911 there is always another species that will line up to take over 512 00:30:45,911 --> 00:30:53,318 when another is done. 513 00:30:53,318 --> 00:30:56,354 The lion is so stuffed his belly is stretched, 514 00:30:56,354 --> 00:31:00,192 but even still he is reluctant to concede defeat and leave his 515 00:31:00,192 --> 00:31:09,668 prize to the croc. 516 00:31:09,668 --> 00:31:24,249 (Lion roars) 517 00:31:24,249 --> 00:31:32,057 The lion retreats. 518 00:31:32,057 --> 00:31:35,327 Backing off was a good decision for the young lion. 519 00:31:35,327 --> 00:31:38,130 Even on land and out of it's element, 520 00:31:38,130 --> 00:31:41,133 a croc is formidable foe. 521 00:31:41,133 --> 00:31:44,269 It has the strongest bite force in the animal kingdom - at 522 00:31:44,269 --> 00:31:47,606 least three times that of a lion. 523 00:31:47,606 --> 00:31:50,609 While the crocodiles in this little river do what they can to 524 00:31:50,609 --> 00:31:54,146 get a meal - their brothers in the Mara River are in their 525 00:31:54,146 --> 00:32:05,524 element and getting ready for their annual feast. 526 00:32:05,524 --> 00:32:09,427 This is the Mara river and this is the last major obstacle that 527 00:32:09,427 --> 00:32:12,130 these newborns will have to contend with, 528 00:32:12,130 --> 00:32:15,167 but not only do they need to cross this river and potentially 529 00:32:15,167 --> 00:32:18,170 choose a bad crossing place and die in the thousands, 530 00:32:18,170 --> 00:32:21,039 they also need to navigate themselves around monster 531 00:32:21,039 --> 00:32:24,643 crocodiles that's lying here waiting for an entire year for 532 00:32:24,643 --> 00:32:34,686 this very crossing. 533 00:32:34,686 --> 00:32:42,627 this very crossing. 534 00:32:42,627 --> 00:32:46,097 There is a huge crocodile in the river. 535 00:32:46,097 --> 00:32:50,035 What's extremely interesting about crocodiles in general are 536 00:32:50,035 --> 00:32:52,771 that they are cold blooded, so they don't need to eat food on a 537 00:32:52,771 --> 00:32:56,208 daily basis to keep their body temperatures warm. 538 00:32:56,208 --> 00:33:02,414 A croc of this size only needs one decent meal once a year. 539 00:33:02,414 --> 00:33:06,651 These huge Nile crocodiles are probably our best look into what 540 00:33:06,651 --> 00:33:10,822 massive dinosaurs looked like. They have stayed unchanged 541 00:33:10,822 --> 00:33:14,059 since the dinosaur era, and they're probably the best 542 00:33:14,059 --> 00:33:18,797 example of something that's so custom designed to - to 543 00:33:18,797 --> 00:33:19,998 the way they live. 544 00:33:19,998 --> 00:33:23,768 And they didn't need to evolve much since those early days. 545 00:33:23,768 --> 00:33:27,372 They can completely submerge themselves with only their 546 00:33:27,372 --> 00:33:30,375 nostrils and their eyes above the water and still even then it 547 00:33:30,375 --> 00:33:33,144 just looks like four pebbles that's in the water, 548 00:33:33,144 --> 00:33:37,315 and get right in close to make effective kills. 549 00:33:37,315 --> 00:33:40,151 For us to experience crocodiles making a kill, 550 00:33:40,151 --> 00:33:43,788 it's very important to be here the moment these first herds of 551 00:33:43,788 --> 00:33:46,858 wildebeest will arrive at the riverbanks and start crossing, 552 00:33:46,858 --> 00:33:48,426 because that's when when the crocodile 553 00:33:48,426 --> 00:33:55,567 will more than likely make a kill. 554 00:33:55,567 --> 00:33:59,204 (Crocodile Splashes) 555 00:33:59,204 --> 00:34:07,712 ♪ 556 00:34:07,712 --> 00:34:11,116 . It's now August, and soon the wildebeest herds will be back at 557 00:34:11,116 --> 00:34:14,753 the Mara River. This is where Jean started to track the herd 558 00:34:14,753 --> 00:34:17,489 almost a year ago. 559 00:34:17,489 --> 00:34:19,457 The journey has covered 10 months, 560 00:34:19,457 --> 00:34:20,892 and it is almost at an end. 561 00:34:20,892 --> 00:34:25,697 ♪ 562 00:34:25,697 --> 00:34:27,699 The Mara River is the lifeblood of the 563 00:34:27,699 --> 00:34:30,802 Northern Serengeti Ecosystem. 564 00:34:30,802 --> 00:34:34,205 It spans two countries, beginning in the highlands of 565 00:34:34,205 --> 00:34:38,877 Southern Kenya, snaking it's way across the Tanzanian border, 566 00:34:38,877 --> 00:34:41,313 and emptying into Lake Victoria. 567 00:34:41,313 --> 00:34:44,749 It's constant flows divides the park into two. 568 00:34:44,749 --> 00:34:48,420 The wildebeest are headed to open grasslands on the opposite 569 00:34:48,420 --> 00:34:55,260 side of the river where they'll spend the next three months. 570 00:34:55,260 --> 00:35:00,598 I'm on my way to try and find the front end of the migration. 571 00:35:00,598 --> 00:35:04,869 This time of year they already should have been kind of all 572 00:35:04,869 --> 00:35:07,339 over the Northern part of the Serengeti. 573 00:35:07,339 --> 00:35:11,409 I'm just driving hill after hill, and plain after plain, 574 00:35:11,409 --> 00:35:14,612 and there is absolutely nothing out here. 575 00:35:14,612 --> 00:35:17,382 It's a little bit disheartening, 576 00:35:17,382 --> 00:35:22,187 you know, to just, uh - not see a thing around. 577 00:35:22,187 --> 00:35:26,391 An entire industry is dependent upon the migration that was 578 00:35:26,391 --> 00:35:30,495 supposed to be here already about a month ago, and for some 579 00:35:30,495 --> 00:35:33,898 reason, it seems that they have flanked to the 580 00:35:33,898 --> 00:35:37,969 North and a little bit to the West of this very crucial 581 00:35:37,969 --> 00:35:42,240 Northern Serengeti, or called Kogatende area. 582 00:35:42,240 --> 00:35:46,544 . As the week progresses there is still no sign of the 583 00:35:46,544 --> 00:35:52,584 wildebeest. Jean has no choice but to wait them out. 584 00:35:52,584 --> 00:35:55,920 The herds were last seen heading out of the Serengeti 585 00:35:55,920 --> 00:35:59,557 National Park into private land where even wildlife 586 00:35:59,557 --> 00:36:02,727 experts like Jean are not allowed. 587 00:36:02,727 --> 00:36:04,562 Where and when the wildebeests will re-enter 588 00:36:04,562 --> 00:36:08,299 the park is anyone's guess. 589 00:36:08,299 --> 00:36:10,869 The reason for the delay is the lack of rain. 590 00:36:10,869 --> 00:36:13,004 The wildebeest herds follow the rain. 591 00:36:13,004 --> 00:36:17,542 But no rain means the grasses which should be lush and green, 592 00:36:17,542 --> 00:36:20,545 are still dry and brown. 593 00:36:20,545 --> 00:36:23,982 Soon, storm clouds begin to build on the horizon, 594 00:36:23,982 --> 00:36:30,455 fueled by moisture from nearby Lake Victoria. 595 00:36:30,455 --> 00:36:33,758 Little by little, they grow into massive thunder clouds, 596 00:36:33,758 --> 00:36:41,833 until they burst in a torrent of rain. 597 00:36:41,833 --> 00:36:44,436 These short intense storms criss-cross the Northern 598 00:36:44,436 --> 00:36:47,705 Serengeti and head towards the grasslands North of the 599 00:36:47,705 --> 00:36:51,042 Mara River. 600 00:36:51,042 --> 00:36:58,416 (Thunder Roars) 601 00:36:58,416 --> 00:37:01,920 It only takes a few days of rain to give life to the land, 602 00:37:01,920 --> 00:37:06,925 and before long, the area is green with new grass. 603 00:37:06,925 --> 00:37:14,966 All that's left now is for the wildebeest to come. 604 00:37:14,966 --> 00:37:18,036 So I arrived in the area a little bit early. 605 00:37:18,036 --> 00:37:22,073 The migration is yet to arrive but there was some big 606 00:37:22,073 --> 00:37:25,410 thundershowers last night and that generally will 607 00:37:25,410 --> 00:37:27,512 pull in the herds. 608 00:37:27,512 --> 00:37:30,682 So there's not much more to do but sit here and wait here. 609 00:37:30,682 --> 00:37:35,320 I can imagine worse places to wait than here in the Serengeti. 610 00:37:35,320 --> 00:37:39,057 . And with the rains, the wildebeest begin to move. 611 00:37:39,057 --> 00:37:42,760 Now the question is, where will they show up? 612 00:37:42,760 --> 00:37:52,804 613 00:37:52,804 --> 00:37:59,644 614 00:37:59,644 --> 00:38:02,080 The next morning, Jean gets out at first light in 615 00:38:02,080 --> 00:38:15,793 search of the advancing herds he knows will be coming. 616 00:38:15,793 --> 00:38:23,868 ♪ 617 00:38:23,868 --> 00:38:27,839 In front of me is where we saw that storm last night and an 618 00:38:27,839 --> 00:38:30,575 area in front of us is called Bologonjo and behinds me is 619 00:38:30,575 --> 00:38:35,613 Kogatende, and I suspect to find the big herds just over this 620 00:38:35,613 --> 00:38:40,385 rise, but the big concern is that if they go just slightly 621 00:38:40,385 --> 00:38:45,423 East, they can go into Kenya and cross the river in the Masai 622 00:38:45,423 --> 00:38:47,392 Mara, which is on the Kenyan side, 623 00:38:47,392 --> 00:38:51,729 meaning that the entire Northern Tanzania is going to miss out on 624 00:38:51,729 --> 00:38:55,066 seeing a migration and river crossings this season. 625 00:38:55,066 --> 00:38:58,970 Kenya is actually just a couple of miles over that way, but 626 00:38:58,970 --> 00:39:03,174 to reach that we have to go all the way back to Arusha, 627 00:39:03,174 --> 00:39:05,843 and that's about a two day journey to then get into the 628 00:39:05,843 --> 00:39:07,011 Masai Mara. 629 00:39:07,011 --> 00:39:10,548 So I really hope that the animals that's potentially in 630 00:39:10,548 --> 00:39:13,685 front of us is gonna swing West and come a little bit 631 00:39:13,685 --> 00:39:16,821 down-river and have a couple of crossings down 632 00:39:16,821 --> 00:39:18,990 on the Tanzania side. 633 00:39:18,990 --> 00:39:21,593 . But Jean doesn't have to wait long. 634 00:39:21,593 --> 00:39:24,529 Just over the next rise, he finds that the wildebeest 635 00:39:24,529 --> 00:39:26,164 have arrived. 636 00:39:26,164 --> 00:39:28,199 There are so many animals, they dominate the 637 00:39:28,199 --> 00:39:30,835 plains and surrounding hills. 638 00:39:30,835 --> 00:39:32,103 They just crossed a little stream, and all of these 639 00:39:32,103 --> 00:39:33,905 wildebeests are coming down to drink. 640 00:39:33,905 --> 00:39:35,807 It's about midday, very hot, 641 00:39:35,807 --> 00:39:40,612 so there are thousands around. 642 00:39:40,612 --> 00:39:42,780 . They are moving towards the Mara River to make 643 00:39:42,780 --> 00:39:44,015 the crossing. 644 00:39:44,015 --> 00:39:47,518 Now the question is, where will they cross? 645 00:39:47,518 --> 00:39:51,856 Will they head into Kenya? Or will they stay in Tanzania? 646 00:39:51,856 --> 00:39:55,727 A male shows interest in a passing female. 647 00:39:55,727 --> 00:39:58,062 It will soon be the annual run when the wildebeest 648 00:39:58,062 --> 00:39:59,697 will mate again. 649 00:39:59,697 --> 00:40:03,835 For now though, they have a river to cross. 650 00:40:03,835 --> 00:40:07,171 So we just came over hill and we hit the Mara River, and there's 651 00:40:07,171 --> 00:40:11,743 a big group of wildebeest starting to pack along the banks 652 00:40:11,743 --> 00:40:14,846 of the river, and this is normally a good sign of them 653 00:40:14,846 --> 00:40:16,080 wanting to cross. The general 654 00:40:16,080 --> 00:40:21,519 direction here is to keep on going North so these animals are 655 00:40:21,519 --> 00:40:25,556 vacantly lining up for crossing. It might happen today, 656 00:40:25,556 --> 00:40:26,591 it might happen tomorrow morning, 657 00:40:26,591 --> 00:40:28,726 I mean, the only way you're going to see it is 658 00:40:28,726 --> 00:40:35,733 to hang around and wait. 659 00:40:35,733 --> 00:40:39,037 . The wildebeest migration is one of the greatest spectacles 660 00:40:39,037 --> 00:40:40,938 in the animal kingdom. 661 00:40:40,938 --> 00:40:44,909 They spend their lives almost constantly on the move in a 662 00:40:44,909 --> 00:40:48,212 circle that takes them around the Serengeti. 663 00:40:48,212 --> 00:40:51,683 It's August, and they are heading back North. 664 00:40:51,683 --> 00:40:54,185 One obstacle remains, the crossing of the crocodile 665 00:40:54,185 --> 00:40:59,123 infested Mara River. 666 00:40:59,123 --> 00:41:02,727 So we just came over hill and we hit the Mara river, and there's 667 00:41:02,727 --> 00:41:07,532 a big group of wildebeests starting to pack along the banks 668 00:41:07,532 --> 00:41:10,568 of the river, and this is normally a good sign of them 669 00:41:10,568 --> 00:41:12,970 wanting to cross. It might happen today, might happen 670 00:41:12,970 --> 00:41:15,606 tomorrow morning, I mean, the only way you're gonna see it is 671 00:41:15,606 --> 00:41:18,209 to hang around and wait. 672 00:41:18,209 --> 00:41:20,812 . Jean will keep following the herds. 673 00:41:20,812 --> 00:41:23,014 It was 6 months ago that the young wildebeest 674 00:41:23,014 --> 00:41:25,550 were born. 675 00:41:25,550 --> 00:41:28,686 This river crossing is a major event for adult wildebeest who 676 00:41:28,686 --> 00:41:31,122 have done this before, but this 677 00:41:31,122 --> 00:41:34,025 is the first time that the little ones have ever seen or 678 00:41:34,025 --> 00:41:38,563 experienced this river. 679 00:41:38,563 --> 00:41:41,332 Evolution has timed the birth so that the newborns have had 680 00:41:41,332 --> 00:41:44,836 enough time to develop their strength and coordination 681 00:41:44,836 --> 00:41:48,039 before they encounter the river. 682 00:41:48,039 --> 00:41:51,209 . Yeah, this group in front of me is probably about 2 to 3000 683 00:41:51,209 --> 00:41:54,011 and counting, but after the North, 684 00:41:54,011 --> 00:41:57,715 there's another group of a couple of thousand. Seems like 685 00:41:57,715 --> 00:41:59,917 they - they would see these guys running, and they're on their 686 00:41:59,917 --> 00:42:03,588 way here, but then down to the South, there's another very 687 00:42:03,588 --> 00:42:08,726 large group that's also pushing onto the river, so I think I'm 688 00:42:08,726 --> 00:42:14,899 in the best position now to kind of scout all the areas, and 689 00:42:14,899 --> 00:42:16,968 we'll see where it starts to happen, and they'll make their 690 00:42:16,968 --> 00:42:19,270 choice from there. 691 00:42:19,270 --> 00:42:22,206 . Jean has timed his arrival perfectly. The second 692 00:42:22,206 --> 00:42:25,710 column of wildebeest advancing up the Western side 693 00:42:25,710 --> 00:42:28,613 has now broken out of the wilderness zone, and into 694 00:42:28,613 --> 00:42:32,817 Kogatende. They are heading straight towards him. It is 695 00:42:32,817 --> 00:42:36,220 shaping up to be a mega crossing. In spite of the 696 00:42:36,220 --> 00:42:39,857 presence of thousands of wildebeest on the shores,the 697 00:42:39,857 --> 00:42:42,860 crocodiles lie still. 698 00:42:42,860 --> 00:42:46,631 Crossing point after crossing point is passed up, 699 00:42:46,631 --> 00:42:48,866 as the lead animals assess their chances 700 00:42:48,866 --> 00:42:52,870 of survival. 701 00:42:52,870 --> 00:42:58,075 Finally, they choose, and a single animal descends, 702 00:42:58,075 --> 00:43:01,345 unleashing a waterfall of wildebeest behind. 703 00:43:01,345 --> 00:43:09,053 (Wildebeest Gallop) 704 00:43:09,053 --> 00:43:23,167 These animals don't plan to wait - they are ready to cross. 705 00:43:23,167 --> 00:43:33,311 The first wildebeest jumps, followed by it's yearling. 706 00:43:33,311 --> 00:43:35,880 The others following behind them. 707 00:43:35,880 --> 00:43:38,382 Within seconds, hundreds of animals begin to snake 708 00:43:38,382 --> 00:43:40,718 their way across the river. 709 00:43:40,718 --> 00:43:52,129 (Wildebeest Grunt) 710 00:43:52,129 --> 00:43:56,167 The crocs are drawn to the commotion. 711 00:43:56,167 --> 00:43:59,237 So these wildebeest have been crossing the whole morning, and 712 00:43:59,237 --> 00:44:02,073 there's 2 or 3 huge crocodiles that's making their 713 00:44:02,073 --> 00:44:16,821 way in the line of wildebeests crossing. 714 00:44:16,821 --> 00:44:19,857 . The crocs get into position as the wildebeest 715 00:44:19,857 --> 00:44:24,195 struggle to get up the other side. 716 00:44:24,195 --> 00:44:35,039 Having seen the crocs, the rest of the herd stops crossing. 717 00:44:35,039 --> 00:44:38,009 Two crocs take aim on a yearling, but luckily the 718 00:44:38,009 --> 00:44:41,012 animal finds ground below the water, and is able to out 719 00:44:41,012 --> 00:44:47,251 maneuver them. 720 00:44:47,251 --> 00:44:54,525 They quickly scramble up the far bank to safety. 721 00:44:54,525 --> 00:45:08,940 One of the crocs has caught caught a wildebeest. 722 00:45:08,940 --> 00:45:10,174 . Just towards the end of the crossing, there was this 723 00:45:10,174 --> 00:45:13,911 enormous croc that got a hold of a yearling that was struggling 724 00:45:13,911 --> 00:45:16,047 to get up the rocks, and it pulled it down, and then the 725 00:45:16,047 --> 00:45:19,150 second crocodile came in, and literally just took the entire 726 00:45:19,150 --> 00:45:23,955 head off this wildebeest in his mouth and all of them submerged, 727 00:45:23,955 --> 00:45:32,863 and that's the last we ever saw of all of them. 728 00:45:32,863 --> 00:45:35,199 . With too may crocs to contend with, the wildebeest 729 00:45:35,199 --> 00:45:38,269 have moved on to a new crossing point just down river. 730 00:45:38,269 --> 00:45:48,312 ♪ 731 00:45:48,312 --> 00:45:58,923 ♪ 732 00:45:58,923 --> 00:46:02,426 We have been sitting here now for probably the last 30 minutes 733 00:46:02,426 --> 00:46:07,031 a constant stream of animals is streaming through the river, I 734 00:46:07,031 --> 00:46:10,401 would estimate about now 10,000 animals at least have crossed in 735 00:46:10,401 --> 00:46:16,073 front of us. 736 00:46:16,073 --> 00:46:18,175 . The wildebeest live out their entire life cycle 737 00:46:18,175 --> 00:46:22,380 as a tribe of nomads on the Serengeti plains. 738 00:46:22,380 --> 00:46:23,547 Constantly on the move, 739 00:46:23,547 --> 00:46:27,018 stopping only briefly before they follow the rains again in 740 00:46:27,018 --> 00:46:30,521 search of the next green pasture. 741 00:46:30,521 --> 00:46:33,891 They have evolved as great sustainers of the plains, 742 00:46:33,891 --> 00:46:36,227 caretakers of the land, and also 743 00:46:36,227 --> 00:46:39,530 food for the predators along the way. 744 00:46:39,530 --> 00:46:44,602 It's a naturally evolved, perfectly balanced eco system, 745 00:46:44,602 --> 00:46:47,004 with every blade of grass, every 746 00:46:47,004 --> 00:46:51,075 creature on land, and bird in the sky playing it's part in 747 00:46:51,075 --> 00:46:55,880 this continuous cycle of life on the Serengeti plains. 748 00:46:55,880 --> 00:47:05,923 ♪ 749 00:47:05,923 --> 00:47:20,905 ♪ 750 00:47:20,905 --> 00:47:22,106 . So this is it. 751 00:47:22,106 --> 00:47:25,009 This migration of wildebeest and Zebra are one of the last 752 00:47:25,009 --> 00:47:30,047 remaining mega migrations of the planet, and what makes this so 753 00:47:30,047 --> 00:47:33,617 successful is the fact that the Serengeti has been kept intact 754 00:47:33,617 --> 00:47:35,619 for so many years. 755 00:47:35,619 --> 00:47:39,423 The wildebeest crossed over into Kenya, and this is the 756 00:47:39,423 --> 00:47:43,961 completion of that circle where they would eventually in a 757 00:47:43,961 --> 00:47:47,998 couple of months be pulled down back into Central Serengeti 758 00:47:47,998 --> 00:47:51,268 because of thundershowers that start out that way. 759 00:47:51,268 --> 00:48:01,312 ♪ 760 00:48:01,312 --> 00:48:09,019 ♪ 761 00:48:09,019 --> 00:48:12,019 ♪