1 00:00:16,830 --> 00:00:19,620 For centuries, we've known Arabia 2 00:00:19,820 --> 00:00:22,260 as a desolate and forbidding land. 3 00:00:27,210 --> 00:00:30,410 A vast and barren desert, where little survives. 4 00:00:38,890 --> 00:00:41,050 But there's one corner of Arabia 5 00:00:41,910 --> 00:00:43,810 where life thrives. 6 00:00:49,980 --> 00:00:53,670 A mountain range that rises dramatically from the ocean below. 7 00:01:03,030 --> 00:01:07,160 Once a year, this coast undergoes an amazing transformation. 8 00:01:21,970 --> 00:01:24,190 Making it home to more 9 00:01:24,200 --> 00:01:27,380 wildlife than anywhere else in Arabia. 10 00:01:40,380 --> 00:01:44,620 In the far south of Arabia, on the border between Oman and Yemen, 11 00:01:45,400 --> 00:01:47,150 lies the Dhofar coast. 12 00:01:57,770 --> 00:02:00,180 Here, beside the Indian Ocean, 13 00:02:00,850 --> 00:02:04,580 a range of mountains rises 1,000 metres from the shore. 14 00:02:08,190 --> 00:02:12,800 This remote region is home to an amazing variety of wildlife. 15 00:02:30,680 --> 00:02:32,290 It's January in Dhofar. 16 00:02:35,670 --> 00:02:38,360 The start of a year in which a team of biologists 17 00:02:38,400 --> 00:02:41,280 will try to discover what makes Dhofar so rich. 18 00:02:47,260 --> 00:02:49,280 Hadi and Khaled Al Hikmani 19 00:02:49,610 --> 00:02:51,100 grew up on this escarpment. 20 00:02:56,700 --> 00:02:59,190 Now, as Omani government researchers, 21 00:02:59,370 --> 00:03:02,270 they want to find out just how many species live here. 22 00:03:12,870 --> 00:03:16,460 Using remote cameras, triggered by an infrared beam, 23 00:03:16,830 --> 00:03:19,280 they hope to film as many animals as they can, 24 00:03:20,350 --> 00:03:21,940 including one so rare, 25 00:03:22,160 --> 00:03:24,200 locals call it a living ghost - 26 00:03:24,600 --> 00:03:25,780 the Arabian leopard. 27 00:03:27,600 --> 00:03:29,970 These cameras will run throughout the year, 28 00:03:30,740 --> 00:03:32,690 opening a window onto the private life 29 00:03:32,780 --> 00:03:35,010 of Dhofar's most elusive animals. 30 00:03:41,440 --> 00:03:43,580 But not all the creatures here are so shy. 31 00:03:49,880 --> 00:03:52,410 A female Verreaux's eagle is on patrol. 32 00:04:08,130 --> 00:04:09,360 She's a fussy eater. 33 00:04:10,740 --> 00:04:12,270 A Pygmy owl won't do. 34 00:04:16,990 --> 00:04:18,770 Her diet is so specialised, 35 00:04:18,960 --> 00:04:20,890 she needs a partner to help capture it. 36 00:04:30,800 --> 00:04:34,380 They're searching for a prey whose nearest living relative 37 00:04:34,490 --> 00:04:35,890 is the African elephant. 38 00:04:39,520 --> 00:04:41,440 The tusks are a giveaway. 39 00:04:43,740 --> 00:04:44,830 A Rock hyrax. 40 00:04:46,410 --> 00:04:48,690 They feed on bushes on the cliff face, 41 00:04:48,800 --> 00:04:50,250 safe from most predators. 42 00:04:52,880 --> 00:04:54,800 But these eagles use a tactic 43 00:04:54,910 --> 00:04:56,610 rarely seen in the bird world. 44 00:05:03,630 --> 00:05:05,190 They go to work as a team. 45 00:05:07,740 --> 00:05:08,800 It won't be easy. 46 00:05:08,850 --> 00:05:11,960 Fan-tailed ravens don't like eagles in their air-space. 47 00:05:20,560 --> 00:05:23,250 This is a test of aerobatic skills. 48 00:05:31,130 --> 00:05:33,760 A nesting kestrel doesn't want the eagles around either. 49 00:06:01,150 --> 00:06:02,290 The eagles split up. 50 00:06:08,030 --> 00:06:09,660 The female hugs the cliff edge... 51 00:06:14,010 --> 00:06:16,310 ..while the male soars in front of the sun... 52 00:06:19,140 --> 00:06:21,320 ...hiding in the blinding light. 53 00:06:25,370 --> 00:06:28,190 But the hyrax have a unique blue-tinted retina 54 00:06:28,350 --> 00:06:30,020 that acts like sunglasses, 55 00:06:31,760 --> 00:06:33,820 allowing them to stare directly back. 56 00:06:35,800 --> 00:06:37,860 They don't let the male eagle out of their sight. 57 00:06:42,820 --> 00:06:45,540 But the male was merely a decoy. 58 00:06:50,850 --> 00:06:53,260 His partner has already made the kill. 59 00:06:57,530 --> 00:07:00,880 By working together, they've captured their favourite meal. 60 00:07:21,670 --> 00:07:23,930 To feed themselves and a hungry chick, 61 00:07:24,530 --> 00:07:26,790 the pair must kill over ten hyrax a week. 62 00:07:35,260 --> 00:07:36,930 These little cousins of the elephant 63 00:07:37,530 --> 00:07:39,260 are part of a rich food chain. 64 00:07:48,390 --> 00:07:52,120 But it's not only the mountains of Dhofar where wildlife thrives. 65 00:08:01,980 --> 00:08:03,160 Just offshore... 66 00:08:05,740 --> 00:08:07,180 ..is the Indian Ocean... 67 00:08:12,390 --> 00:08:14,980 ...home to one of the rarest animals on earth. 68 00:08:21,290 --> 00:08:23,570 It's February and the waters 69 00:08:23,720 --> 00:08:25,760 echo with a song heard nowhere else. 70 00:08:44,720 --> 00:08:46,180 An Arabian humpback whale. 71 00:08:55,760 --> 00:08:58,720 There are less than 100 left on the planet. 72 00:09:05,660 --> 00:09:08,370 They're so special, they've become targets. 73 00:09:42,850 --> 00:09:45,480 Researchers are now on the hunt for whale DNA. 74 00:10:04,780 --> 00:10:07,020 The dart merely pricks the skin 75 00:10:07,380 --> 00:10:09,130 and the whale barely feels a thing, 76 00:10:10,460 --> 00:10:12,620 but the scientists have the sample they need. 77 00:10:21,460 --> 00:10:23,200 The DNA results have revealed something amazing 78 00:10:23,340 --> 00:10:24,990 about this population. 79 00:10:34,160 --> 00:10:37,750 These humpbacks have not bred with any other whales 80 00:10:38,150 --> 00:10:40,260 for over 60,000 years. 81 00:10:45,410 --> 00:10:48,140 The last time they met with others of their kind, 82 00:10:48,620 --> 00:10:51,060 sabre-toothed cats roamed the earth 83 00:10:51,520 --> 00:10:55,520 and the Arabian peninsula was still joined to Asia by land. 84 00:11:02,280 --> 00:11:04,050 Using underwater microphones, 85 00:11:04,470 --> 00:11:07,500 scientists are recording whale songs never heard before 86 00:11:08,300 --> 00:11:11,440 and think they may have discovered a new race of whales. 87 00:11:24,310 --> 00:11:28,290 Perhaps the most remarkable discovery about these whales 88 00:11:28,800 --> 00:11:32,250 is that they're the only humpbacks in the world that don't migrate. 89 00:11:36,010 --> 00:11:39,030 All other humpbacks breed in warm oceans, 90 00:11:39,180 --> 00:11:41,420 then travel to polar waters to feed. 91 00:11:43,030 --> 00:11:45,780 Only cold water carries the nutrients they need. 92 00:11:52,840 --> 00:11:54,750 But in 60,000 years, 93 00:11:55,120 --> 00:11:58,710 these humpbacks of the Arabian Sea have never left. 94 00:12:07,530 --> 00:12:10,420 For these giants to survive here year-round, 95 00:12:10,870 --> 00:12:14,280 cold water full of food must arrive from somewhere. 96 00:12:20,510 --> 00:12:24,400 This holds the key, not just for the humpbacks' survival, 97 00:12:24,550 --> 00:12:27,050 but for all life in these coastal mountains. 98 00:12:36,990 --> 00:12:40,090 But for now, these waters remain warm and barren, 99 00:12:40,380 --> 00:12:42,150 just like the Arabian coastline. 100 00:12:49,500 --> 00:12:50,230 It's April, 101 00:12:50,580 --> 00:12:54,030 and not a drop of rain has fallen in the mountains for over six months. 102 00:13:02,410 --> 00:13:04,130 Arabia is so dry that 103 00:13:04,430 --> 00:13:06,330 not a single river flows permanently 104 00:13:06,480 --> 00:13:08,100 on this entire sub-continent. 105 00:13:12,090 --> 00:13:15,510 The daytime temperature reaches 45 degrees Celsius. 106 00:13:31,370 --> 00:13:33,180 Shamal winds from the north 107 00:13:33,340 --> 00:13:37,060 bring no relief for those living in the Dhofar mountains 108 00:13:44,820 --> 00:13:48,300 Hadi and Khaled's families have herded goats here for generations. 109 00:13:52,620 --> 00:13:55,390 They are Jabali people, originally from Africa. 110 00:13:56,480 --> 00:13:59,150 At this time of year, they travel far and wide 111 00:13:59,310 --> 00:14:00,660 to find grazing for their animals. 112 00:14:05,060 --> 00:14:08,320 Hadi and Khaled's village sits on the top of the Dhofar escarpment. 113 00:14:17,640 --> 00:14:20,730 Khaled's mother carries a weapon to protect her flock. 114 00:14:27,230 --> 00:14:28,750 In these remote mountains, 115 00:14:28,940 --> 00:14:31,270 their livestock are exposed to predators. 116 00:14:33,870 --> 00:14:35,370 And in the heat of early summer, 117 00:14:37,340 --> 00:14:39,890 it seems the predators are becoming more bold. 118 00:14:42,850 --> 00:14:44,540 A neighbour has called for Khaled's help. 119 00:14:47,820 --> 00:14:49,120 As a government researcher, 120 00:14:49,530 --> 00:14:52,340 he's first on call when wildlife comes into the village. 121 00:15:01,800 --> 00:15:03,390 Once a predator breaks in, 122 00:15:04,310 --> 00:15:06,150 there's usually only one outcome. 123 00:15:15,790 --> 00:15:18,090 The teeth marks suggest a large carnivore. 124 00:15:20,480 --> 00:15:21,910 Losing one goat is bad. 125 00:15:22,440 --> 00:15:25,680 The loss of eight goats will hit the family very hard. 126 00:15:30,450 --> 00:15:31,240 In the past, 127 00:15:31,410 --> 00:15:33,790 Khaled's village would've set out to hunt this killer. 128 00:15:37,190 --> 00:15:39,220 Now Khaled wants to hunt for answers. 129 00:15:42,640 --> 00:15:45,210 He suspects the killer will return to the scene of the crime. 130 00:15:48,660 --> 00:15:51,390 He sets a trap with remote-control cameras. 131 00:15:55,020 --> 00:15:58,250 An image of the culprit may help efforts to compensate farmers. 132 00:16:13,230 --> 00:16:16,880 Khaled is a goat herder himself, as well as a biologist. 133 00:16:18,810 --> 00:16:22,540 On the one hand, he hopes to protect rare carnivores in these hills. 134 00:16:23,500 --> 00:16:24,170 On the other, 135 00:16:24,580 --> 00:16:27,350 his family rely on him to keep their goats safe. 136 00:16:59,590 --> 00:17:01,320 It's a clear, starry night, 137 00:17:01,630 --> 00:17:02,770 but there's no moon. 138 00:17:03,840 --> 00:17:05,370 When the village lights go out, 139 00:17:05,610 --> 00:17:06,680 it's pitch black. 140 00:17:07,770 --> 00:17:10,320 Only by using a special heat-sensitive camera 141 00:17:10,360 --> 00:17:12,110 can we witness the night's drama. 142 00:17:17,570 --> 00:17:20,390 The thermal camera shows a cold, dark night 143 00:17:20,470 --> 00:17:22,200 dotted with warm-blooded mammals. 144 00:17:27,170 --> 00:17:29,900 To the human eye, there's nothing but darkness. 145 00:17:38,010 --> 00:17:40,970 The night-watchman can't see the predators gathering. 146 00:17:50,080 --> 00:17:51,610 Arabian wolves. 147 00:17:53,710 --> 00:17:55,420 The Jabali often hear wolves, 148 00:17:55,700 --> 00:17:58,410 but no-one knew they came so close to the village. 149 00:18:07,620 --> 00:18:10,190 They have rarely been seen in groups bigger than four. 150 00:18:12,740 --> 00:18:15,740 This pack numbers 12 individuals, 151 00:18:15,810 --> 00:18:17,370 the largest ever recorded - 152 00:18:17,710 --> 00:18:19,570 a clear sign there's more food for them 153 00:18:19,740 --> 00:18:20,570 in the Dhofar mountains 154 00:18:20,740 --> 00:18:22,160 than anywhere else in Arabia. 155 00:18:24,380 --> 00:18:26,770 But they may not be the only ones feasting tonight. 156 00:18:33,730 --> 00:18:34,930 The party's over. 157 00:18:39,350 --> 00:18:43,070 There's only one beast not afraid to take on 12 wolves. 158 00:18:46,440 --> 00:18:49,270 A female striped hyena moves into position. 159 00:18:54,200 --> 00:18:56,930 The scout can't see the intruder in the darkness. 160 00:19:01,480 --> 00:19:03,360 And the hyena makes her move. 161 00:19:09,740 --> 00:19:12,980 One-on-one, a wolf is no match for a hyena. 162 00:19:17,990 --> 00:19:20,890 She's not quick, but she's immensely strong. 163 00:19:22,230 --> 00:19:25,120 With one bite, she could crush a wolf's skull. 164 00:19:45,740 --> 00:19:48,590 In the darkness, the wolves lose their nerve, 165 00:19:49,560 --> 00:19:51,400 and the thief helps herself. 166 00:20:04,910 --> 00:20:07,340 Dhofar is one of the few places on earth 167 00:20:07,600 --> 00:20:10,110 where wolves and hyenas come face-to-face. 168 00:20:15,670 --> 00:20:18,160 But it won't be the rivalry between the two species 169 00:20:18,340 --> 00:20:19,370 that affects their survival. 170 00:20:28,000 --> 00:20:31,290 It's the conflict between predators and Jabali farmers 171 00:20:31,410 --> 00:20:33,510 that Hadi and Khaled are most concerned about. 172 00:20:47,420 --> 00:20:48,260 At dawn, Hadi and Khaled 173 00:20:48,710 --> 00:20:50,890 download their cameras. 174 00:20:53,120 --> 00:20:54,810 The villagers heard wolves, 175 00:20:55,270 --> 00:20:58,280 but the appearance of a striped hyena is a surprise. 176 00:21:08,130 --> 00:21:10,280 The video will be a useful first step 177 00:21:10,370 --> 00:21:12,900 in resolving the locals' conflict with predators. 178 00:21:25,060 --> 00:21:27,590 If they can identify individual culprits, 179 00:21:27,830 --> 00:21:30,030 it may prevent indiscriminate revenge. 180 00:21:43,810 --> 00:21:47,420 The cameras not only capture the behaviour of large carnivores, 181 00:21:48,120 --> 00:21:51,320 they shed light on some more obscure night hunters. 182 00:22:03,350 --> 00:22:05,390 Honey badgers usually forage alone. 183 00:22:11,840 --> 00:22:14,550 In the mountains, it appears they roam in packs. 184 00:22:21,290 --> 00:22:23,380 And then a sight of one 185 00:22:23,550 --> 00:22:25,330 the rarest animals in the world... 186 00:22:27,910 --> 00:22:29,450 an Arabian leopard. 187 00:22:36,420 --> 00:22:38,200 These are the shots they're after. 188 00:22:41,020 --> 00:22:42,870 They set out to check their cameras, 189 00:22:42,980 --> 00:22:46,140 covering over 100 miles of the Dhofar mountains. 190 00:23:03,130 --> 00:23:08,070 The cameras are capturing a rich food chain, from top to bottom. 191 00:23:23,500 --> 00:23:27,080 Hadi and Khaled's results are revealing a remarkable web of life. 192 00:23:29,010 --> 00:23:32,190 But what is the one thing that connects all this wildlife 193 00:23:33,010 --> 00:23:35,370 and makes the Dhofar mountains so rich? 194 00:23:39,520 --> 00:23:43,580 The answer lies in their position, right by the Indian Ocean. 195 00:23:52,350 --> 00:23:55,060 It's May, the hottest month of the year. 196 00:24:01,610 --> 00:24:05,750 And one predator knows that Dhofar's riches come from the sea. 197 00:24:09,010 --> 00:24:10,310 An Arabian fox. 198 00:24:14,640 --> 00:24:17,210 Tonight, this predator from the mountains 199 00:24:17,340 --> 00:24:20,190 will come face-to-face with a creature from the Indian Ocean. 200 00:24:28,240 --> 00:24:32,320 An ancient mariner has brought treasure ashore to bury. 201 00:24:35,510 --> 00:24:39,390 An animal that has changed little since the time of the dinosaurs. 202 00:24:44,800 --> 00:24:47,040 A female green sea turtle. 203 00:24:52,180 --> 00:24:54,710 She is here to do what her ancestors have done 204 00:24:54,720 --> 00:24:57,190 for over 100 million years. 205 00:25:00,480 --> 00:25:01,890 With her hind flippers, 206 00:25:01,990 --> 00:25:04,960 she carefully digs a hole of just the right depth. 207 00:25:07,240 --> 00:25:11,100 Her tears excrete salt and keep sand out of her eyes, 208 00:25:11,330 --> 00:25:13,870 as she lays over 100 eggs. 209 00:25:15,460 --> 00:25:19,130 This is the only activity that will ever bring her ashore. 210 00:25:22,700 --> 00:25:24,550 And it has not gone unnoticed. 211 00:25:26,520 --> 00:25:30,080 Once her eggs are buried, her job as mother is done. 212 00:25:48,040 --> 00:25:50,540 She returns to the sea for another year... 213 00:25:53,310 --> 00:25:55,940 but it's her buried treasure that the thief is after. 214 00:26:07,280 --> 00:26:10,400 An egg is a nutritious meal for this skinny fox. 215 00:26:19,870 --> 00:26:22,710 A second female arrives to take her chances. 216 00:26:25,370 --> 00:26:28,840 Two more, and the turtles are improving their odds. 217 00:26:32,680 --> 00:26:34,510 But the fox isn't alone either. 218 00:26:46,770 --> 00:26:50,820 These foxes can dig up eggs quicker than turtles can bury them. 219 00:26:51,590 --> 00:26:54,660 Theirs is the most specialised diet of any fox. 220 00:26:55,950 --> 00:27:00,440 90% of everything they eat in their whole life will be turtle eggs. 221 00:27:02,270 --> 00:27:05,160 There is little the turtles can do to defend their clutch, 222 00:27:05,560 --> 00:27:08,500 but they have one strategy the foxes can never match. 223 00:27:10,330 --> 00:27:11,040 Numbers. 224 00:27:13,820 --> 00:27:17,090 Each year, over 10,000 female turtles 225 00:27:17,120 --> 00:27:20,140 lay over three million eggs along this coast. 226 00:27:21,980 --> 00:27:24,550 It would take the foxes over 50 years 227 00:27:24,690 --> 00:27:26,440 to eat this season's batch alone. 228 00:27:46,870 --> 00:27:51,000 Riches from the Indian Ocean are feeding the Arabian land. 229 00:27:53,400 --> 00:27:57,240 Ultimately, all of Dhofar's riches are sustained by the sea. 230 00:28:00,010 --> 00:28:05,280 And the sea itself is undergoing a radical transformation. 231 00:28:08,280 --> 00:28:10,940 Warm surface waters are being dragged away, 232 00:28:11,460 --> 00:28:14,350 sucked to the north by the mighty Indian monsoon. 233 00:28:18,470 --> 00:28:20,600 An oceanic vacuum is created, 234 00:28:20,830 --> 00:28:22,690 and something must fill the space. 235 00:28:27,910 --> 00:28:30,070 Cold water wells up from the depths, 236 00:28:30,140 --> 00:28:32,330 bringing nutrients from the sea floor with it. 237 00:28:47,250 --> 00:28:50,190 Chilled water also holds more oxygen, 238 00:28:50,420 --> 00:28:53,160 and more oxygen means more life. 239 00:28:55,990 --> 00:28:59,060 As the temperature drops, these seas are transforming 240 00:28:59,240 --> 00:29:01,050 into some of the richest in the world. 241 00:29:05,950 --> 00:29:10,960 Microscopic plankton flourish, and an explosion of life begins. 242 00:29:16,310 --> 00:29:20,130 Fish from every corner of the Indian Ocean have come to feed. 243 00:29:22,020 --> 00:29:23,040 Fusiliers. 244 00:29:25,050 --> 00:29:26,340 Blue triggerfish. 245 00:29:32,440 --> 00:29:34,590 And graceful devil rays. 246 00:29:37,870 --> 00:29:41,590 Some have travelled from as far as Australia to enjoy these riches. 247 00:29:47,790 --> 00:29:50,650 This is why the humpbacks never leave. 248 00:29:51,890 --> 00:29:54,690 They don't need to migrate to cold waters to feed. 249 00:29:55,210 --> 00:29:57,280 Cold water comes to them. 250 00:30:02,570 --> 00:30:03,190 And this bounty 251 00:30:03,360 --> 00:30:06,420 attracts one species that arrives not in thousands, 252 00:30:07,600 --> 00:30:08,870 not even millions. 253 00:30:12,900 --> 00:30:16,660 The Indian oil sardine arrives in billions. 254 00:30:19,610 --> 00:30:23,200 A single shoal can be over three miles long. 255 00:30:46,100 --> 00:30:49,220 By moving in unison, they confuse predators. 256 00:30:53,160 --> 00:30:54,410 Rays are too slow. 257 00:30:58,340 --> 00:31:01,360 Socotra cormorants struggle to pick a target. 258 00:31:06,370 --> 00:31:09,010 But synchronised swimming won't protect them 259 00:31:09,040 --> 00:31:11,420 from the ocean's most voracious predator... 260 00:31:13,920 --> 00:31:15,420 man. 261 00:31:18,610 --> 00:31:22,240 The arrival of the sardines means the Jabali mountain-men 262 00:31:22,290 --> 00:31:23,840 become part-time fishermen. 263 00:31:30,030 --> 00:31:32,900 Over half a million tonnes of fish will be brought in. 264 00:32:16,180 --> 00:32:18,820 While the cold water is a boon for sardines, 265 00:32:20,260 --> 00:32:22,950 it's brought hard times for the resident corals. 266 00:32:24,780 --> 00:32:28,660 The water temperature has dropped ten degrees in a matter of weeks. 267 00:32:30,790 --> 00:32:34,700 Tropical species are now being overrun by a cold-water bully. 268 00:32:40,800 --> 00:32:45,280 Kelp grows up to 50 centimetres per day, smothering the reef. 269 00:32:50,910 --> 00:32:54,410 Most warm-water residents have no choice but to stay put. 270 00:33:02,120 --> 00:33:08,280 A lone clown-fish. He has made his home in a small anemone. 271 00:33:08,730 --> 00:33:12,540 A tiny tropical island in a sea that's turned cold. 272 00:33:21,250 --> 00:33:25,440 For these tropical species, their world has been turned upside down. 273 00:33:40,570 --> 00:33:44,780 The Indian monsoon has struck the Dhofar coast. 274 00:34:12,440 --> 00:34:14,980 The monsoon brings with it the magic ingredient 275 00:34:15,010 --> 00:34:17,180 that sustains life in these mountains. 276 00:34:20,280 --> 00:34:22,930 The chilled waters cool the air above them. 277 00:34:28,640 --> 00:34:31,180 Creating clouds which pour inland. 278 00:35:01,950 --> 00:35:03,650 The air is so humid, 279 00:35:04,000 --> 00:35:07,280 the clouds need only touch an object to release their moisture. 280 00:35:17,460 --> 00:35:20,800 The mist is about to work miracles. 281 00:35:27,130 --> 00:35:29,400 Condensation settles on everything. 282 00:35:53,860 --> 00:35:55,780 Some homes are water-logged. 283 00:35:59,850 --> 00:36:02,000 A female golden orb spider. 284 00:36:06,020 --> 00:36:08,780 Her oily exoskeleton helps keep water out, 285 00:36:09,780 --> 00:36:11,930 but shedding the droplets isn't easy. 286 00:36:28,430 --> 00:36:34,010 Her male is one-tenth her size, and even less skilled at drying off. 287 00:36:49,190 --> 00:36:51,420 Through June, the monsoon builds 288 00:36:51,600 --> 00:36:54,110 into one of the biggest weather systems on earth. 289 00:37:00,210 --> 00:37:03,420 Cool ocean winds meet warm Arabian air 290 00:37:04,190 --> 00:37:06,390 creating vast cloud banks. 291 00:37:25,470 --> 00:37:28,750 The Dhofar escarpment provides the perfect barrier... 292 00:37:30,790 --> 00:37:34,510 trapping the clouds and hijacking their precious moisture. 293 00:37:41,300 --> 00:37:45,440 There is more rainfall here than the rest of Arabia combined. 294 00:37:49,730 --> 00:37:53,900 In July, the monsoon's blanket rests heavy on the land, 295 00:37:55,540 --> 00:37:57,750 and mist turns to rain. 296 00:38:12,520 --> 00:38:15,280 Plants grow on other plants to gain height 297 00:38:15,490 --> 00:38:17,440 and steal as much moisture as they can. 298 00:38:21,020 --> 00:38:22,070 Even the animals here have 299 00:38:22,240 --> 00:38:24,210 amazing methods of catching rain. 300 00:38:26,990 --> 00:38:30,420 The Arabian chameleon absorbs water directly through his skin. 301 00:38:32,510 --> 00:38:35,090 And the head-shield funnels raindrops to his mouth. 302 00:38:38,120 --> 00:38:40,300 Perhaps a little too much, today. 303 00:38:55,350 --> 00:38:58,370 Down below, the ground is now so sodden 304 00:38:58,630 --> 00:39:01,280 that others are emerging from months underground. 305 00:39:04,370 --> 00:39:06,240 Snails have been avoiding the heat, 306 00:39:06,800 --> 00:39:10,160 but now conditions are just right, and there's lots to catch up on. 307 00:39:13,700 --> 00:39:16,390 Snails are seeking other snails. 308 00:39:22,350 --> 00:39:25,660 And the tree trunks have become singles bars. 309 00:39:37,580 --> 00:39:39,000 Within a few short months, 310 00:39:39,320 --> 00:39:41,640 the monsoon moisture has worked its magic... 311 00:39:44,090 --> 00:39:48,940 ...turning the once-parched hills into a green paradise. 312 00:40:00,800 --> 00:40:04,410 This is a side of Arabia that few of us could imagine. 313 00:40:08,860 --> 00:40:12,220 A practically hidden ecosystem springs to life. 314 00:40:38,510 --> 00:40:42,760 The Dhofar coast has become the jewel of Arabia. 315 00:40:45,740 --> 00:40:48,570 By August, the earth cannot soak up any more water 316 00:40:50,420 --> 00:40:53,180 and the Dhofar mountains drain what they can't hold. 317 00:41:12,280 --> 00:41:16,220 When creeks turn to rivers, some opt for a spot of fishing. 318 00:41:17,610 --> 00:41:18,570 There are beginners... 319 00:41:19,470 --> 00:41:20,810 and experts. 320 00:41:24,890 --> 00:41:28,900 A few fish have clung on though the dry season in tiny pools, 321 00:41:29,300 --> 00:41:31,500 and now their numbers explode. 322 00:41:33,400 --> 00:41:36,200 Each pond contains species different to the next, 323 00:41:36,580 --> 00:41:38,300 some found nowhere else on earth. 324 00:41:44,190 --> 00:41:47,650 Millions of litres of water have permeated the mountains, 325 00:41:50,030 --> 00:41:52,350 a treasure that will trickle out all year round 326 00:41:52,510 --> 00:41:57,020 in the form of springs, sustaining life for another year. 327 00:42:08,490 --> 00:42:11,870 Many animals rely on the summer monsoon to build fat reserves 328 00:42:12,020 --> 00:42:13,550 for the lean times ahead. 329 00:42:27,660 --> 00:42:29,440 In the final days of greenery, 330 00:42:30,030 --> 00:42:32,180 the Jabali gather their camels together 331 00:42:32,240 --> 00:42:34,040 to graze in their thousands. 332 00:42:56,310 --> 00:42:59,560 Hadi and Khaled continue their research through the wet season. 333 00:43:09,660 --> 00:43:13,610 After a few short months, the monsoon begins to fade. 334 00:43:17,710 --> 00:43:20,030 September gives way to October, 335 00:43:20,290 --> 00:43:23,490 and the Arabian sun regains control. 336 00:43:39,480 --> 00:43:42,910 Arabia is once again a land without rivers. 337 00:43:56,250 --> 00:44:00,800 Her mountains face the Indian Ocean, awaiting next year's gifts. 338 00:44:18,710 --> 00:44:23,240 By December, Hadi and Khaled's cameras have been running in isolation for a year. 339 00:44:27,990 --> 00:44:29,660 Their persistence has paid off. 340 00:44:31,640 --> 00:44:34,430 Their holy grail appears closer than expected. 341 00:44:49,340 --> 00:44:52,010 Technology has brought them face to face 342 00:44:52,040 --> 00:44:54,500 with one of the most elusive predators on the planet. 343 00:45:11,760 --> 00:45:14,450 Their cameras are not only capturing images, 344 00:45:15,790 --> 00:45:19,060 but the first-ever sound recordings of the leopard's mating call. 345 00:45:50,300 --> 00:45:54,600 Hadi and Khaled will use this footage to raise awareness of the Arabian leopard. 346 00:45:55,810 --> 00:45:58,930 With support from the Oman government, they hope to ensure 347 00:45:59,080 --> 00:46:01,970 the cats' survival in these mountains by the sea. 348 00:46:09,770 --> 00:46:10,970 For the Arabian leopard, 349 00:46:11,260 --> 00:46:13,780 the Dhofar mountains are their last stronghold. 350 00:46:19,140 --> 00:46:20,550 Caves in these cliffs 351 00:46:20,770 --> 00:46:23,200 provide shelter for these secretive creatures. 352 00:46:46,840 --> 00:46:49,210 For the first time ever, we have a glimpse 353 00:46:49,340 --> 00:46:51,980 into the private life of these elusive animals. 354 00:46:58,380 --> 00:47:00,900 And we know now that the leopards 355 00:47:02,100 --> 00:47:04,600 share these mountains with some equally remarkable predators. 356 00:47:12,660 --> 00:47:17,210 The story of the striped hyena is intricately linked with that of the Arabian wolf. 357 00:47:19,660 --> 00:47:21,420 All these large carnivores 358 00:47:21,680 --> 00:47:23,930 sit at the top of a fragile food chain. 359 00:47:25,730 --> 00:47:30,630 A web of life that relies on the spectacular setting of their mountain fortress. 360 00:47:53,330 --> 00:47:56,210 As long as the Indian monsoon sweeps past each summer, 361 00:47:58,170 --> 00:48:02,440 Dhofar will remain home to the greatest diversity of life in Arabia. 362 00:48:17,200 --> 00:48:20,770 There are less than 200 Arabian leopards left in the world. 363 00:48:22,940 --> 00:48:24,440 They are critically endangered. 364 00:48:30,920 --> 00:48:33,270 And yet a simple mist is all 365 00:48:33,420 --> 00:48:35,980 that's needed to sustain this living ghost, 366 00:48:36,780 --> 00:48:40,280 and everything that lives in these Arabian mountains.