1 00:00:35,887 --> 00:00:38,526 ATTENBOROUGH: Whatever your feelings about snakes 2 00:00:38,607 --> 00:00:42,680 you cant deny that they have an extraordinary beauty. 3 00:00:47,167 --> 00:00:51,160 Their lack of limbs compels them to deal with lifes problems 4 00:00:51,247 --> 00:00:54,205 in ways that are utterly different from ours. 5 00:01:01,887 --> 00:01:05,277 But nonetheless the techniques they have developed 6 00:01:05,367 --> 00:01:07,927 are spectacularly successful. 7 00:01:22,327 --> 00:01:25,205 Snakes have one of the simplest of body shapes. 8 00:01:25,287 --> 00:01:27,801 Essentially just a long thin tube. 9 00:01:28,367 --> 00:01:31,996 But they have some remarkably effective ways of getting around. 10 00:01:34,447 --> 00:01:38,565 They can climb a tree simply by embracing its trunk. 11 00:01:44,087 --> 00:01:46,237 Some can flatten their bodies 12 00:01:46,327 --> 00:01:49,603 so that they catch the air beneath them and glide. 13 00:01:54,327 --> 00:01:56,682 By hitching up their undersides 14 00:01:56,767 --> 00:02:00,077 they can inch themselves forward in a straight line. 15 00:02:02,887 --> 00:02:06,675 A sinuous wriggle enables them to skate across loose sand. 16 00:02:11,327 --> 00:02:14,797 And the same action works equally well in water. 17 00:02:17,887 --> 00:02:20,685 There some swim close to the surface. 18 00:02:22,727 --> 00:02:26,686 Others explore the depths and can stay underwater 19 00:02:26,767 --> 00:02:28,519 for hours on end. 20 00:02:30,967 --> 00:02:34,323 One believe it or not can jump. 21 00:02:53,327 --> 00:02:56,637 So leglessness hardly seems such a handicap. 22 00:02:57,527 --> 00:02:59,836 But how did snakes get that way? 23 00:03:00,767 --> 00:03:04,123 Well their remote ancestors 1 00 million years ago 24 00:03:04,207 --> 00:03:07,085 at the time of the dinosaurs did have legs 25 00:03:07,167 --> 00:03:09,317 rather like todays lizards. 26 00:03:16,167 --> 00:03:19,045 Doubtless they were very effective runners. 27 00:03:21,367 --> 00:03:25,155 But some also started to burrow in search of prey. 28 00:03:26,287 --> 00:03:28,721 Below ground legs are a hindrance 29 00:03:28,807 --> 00:03:32,038 and over generations they became smaller. 30 00:03:32,647 --> 00:03:35,525 Today burrowing lizards such as skinks 31 00:03:35,607 --> 00:03:37,882 seem to be going through the same process. 32 00:03:37,967 --> 00:03:40,765 Many have tiny but recognisable legs. 33 00:03:42,367 --> 00:03:46,645 In others the limbs have become nothing more than functionless flaps. 34 00:03:50,447 --> 00:03:54,406 In this burrowing lizard the process has gone even further. 35 00:03:54,487 --> 00:03:57,285 The animal still has the face of a lizard 36 00:03:57,367 --> 00:04:00,006 but its legs have disappeared totally. 37 00:04:04,047 --> 00:04:08,916 It seems that the ancestral snakes went through just such a process 38 00:04:09,007 --> 00:04:13,046 way back in geological history some 92 million years ago. 39 00:04:15,047 --> 00:04:18,403 So what did these very first snakes look like? 40 00:04:18,487 --> 00:04:21,638 Well the answer can be found in Asian jungles 41 00:04:21,727 --> 00:04:27,165 in American woodlands and gardens and even in flowerpots like this. 42 00:04:31,727 --> 00:04:34,287 It may look like an earthworm 43 00:04:35,047 --> 00:04:40,644 but actually its a flowerpot snake and its completely blind. 44 00:04:41,967 --> 00:04:43,400 It doesnt need to see 45 00:04:43,487 --> 00:04:46,081 because it spends all its life underground. 46 00:04:47,487 --> 00:04:52,436 Ill put it back in its flowerpot and put a flower on top 47 00:04:53,087 --> 00:04:57,763 and it will live perfectly happily there in this flowerpot all by itself 48 00:04:57,847 --> 00:04:59,485 providing it has enough food. 49 00:05:00,647 --> 00:05:05,004 And theres a surprising amount for a small snake to eat underground. 50 00:05:05,727 --> 00:05:07,638 Ant larvae for example. 51 00:05:19,567 --> 00:05:23,799 These early legless reptiles flourished and remained underground 52 00:05:23,887 --> 00:05:25,559 for a long time. 53 00:05:26,567 --> 00:05:31,118 Then around 20 million years ago some of them returned to the surface. 54 00:05:35,727 --> 00:05:39,766 Why? Well by this time the dinosaurs had disappeared 55 00:05:39,847 --> 00:05:42,156 and the early mammals had arrived. 56 00:05:42,247 --> 00:05:45,045 They were more nutritious than beetles and worms 57 00:05:45,127 --> 00:05:47,960 so the snakes began to catch them instead 58 00:05:48,047 --> 00:05:50,720 and became so good at doing so that today 59 00:05:50,807 --> 00:05:54,038 they are among the most skilful hunters on Earth. 60 00:05:55,927 --> 00:05:57,758 Here in North America 61 00:05:57,847 --> 00:06:00,759 there is a snake that combines its great speed 62 00:06:00,847 --> 00:06:05,204 and extraordinary senses in a remarkable hunting strategy 63 00:06:05,287 --> 00:06:08,085 we are only just beginning to understand. 64 00:06:11,807 --> 00:06:13,684 A timber rattlesnake. 65 00:06:15,327 --> 00:06:20,355 The morning sun has warmed its body giving it energy and it starts to move. 66 00:06:30,887 --> 00:06:32,286 Its searching for a place 67 00:06:32,367 --> 00:06:35,882 where it can conceal itself and wait for prey to come 68 00:06:35,967 --> 00:06:37,958 within striking distance. 69 00:06:41,687 --> 00:06:44,804 A little chipmunk. Its in no danger yet. 70 00:06:44,887 --> 00:06:48,675 The rattlesnake cant move fast enough to chase and catch it. 71 00:06:51,247 --> 00:06:53,841 But small mammals tend to use the same paths 72 00:06:53,927 --> 00:06:55,519 as they run over the forest floor 73 00:06:55,607 --> 00:06:58,917 and they leave behind a faint trail of scent. 74 00:07:00,167 --> 00:07:03,603 The rattlesnake can detect that scent with its tongue. 75 00:07:11,687 --> 00:07:15,965 It can also locate the warm-blooded chipmunk if its nearby 76 00:07:16,047 --> 00:07:19,517 with heat detectors in a pair of pits beneath its eyes. 77 00:07:22,727 --> 00:07:26,356 As it moves it carefully holds its rattle above the ground 78 00:07:26,447 --> 00:07:28,244 so it makes no noise. 79 00:07:34,487 --> 00:07:39,038 Its chosen the place to wait at the bottom of this tree stump. 80 00:07:39,127 --> 00:07:42,199 Its coloration matches the ground so closely 81 00:07:42,287 --> 00:07:44,642 it needs no further concealment. 82 00:07:45,807 --> 00:07:48,526 Now its just a matter of time. 83 00:07:49,927 --> 00:07:51,519 Seeing a rattlesnake 84 00:07:51,607 --> 00:07:56,761 actually catching its prey is a very very difficult thing to observe. 85 00:07:56,847 --> 00:08:00,283 In fact some scientists have watched rattlesnakes for years 86 00:08:00,367 --> 00:08:03,359 without seeing that particular crucial moment. 87 00:08:03,887 --> 00:08:05,639 But we have a chance 88 00:08:05,727 --> 00:08:09,003 partly because rattlesnakes are ambush hunters 89 00:08:09,087 --> 00:08:12,079 so we know exactly where to put up our gear 90 00:08:12,167 --> 00:08:16,206 and partly because in that gear weve got the very latest 91 00:08:16,287 --> 00:08:18,323 in surveillance equipment. 92 00:08:20,207 --> 00:08:25,042 There are remotely controlled cameras and infrared lights on stands. 93 00:08:29,047 --> 00:08:32,039 And there are motion detectors that will switch on the cameras 94 00:08:32,127 --> 00:08:35,836 if anything moves so I neednt wait alongside. 95 00:08:35,927 --> 00:08:39,761 If anything happens the cameras will switch on automatically. 96 00:08:42,967 --> 00:08:45,003 Later I check the replay. 97 00:08:52,527 --> 00:08:55,166 Theres a mouse just along that log. 98 00:09:06,687 --> 00:09:08,359 That obviously came to nothing 99 00:09:08,687 --> 00:09:12,726 but the cameras have started recording again and the snake is moving. 100 00:09:12,807 --> 00:09:15,719 Hes checking out the trail with his tongue. 101 00:09:18,967 --> 00:09:22,801 (WHISPERING) See thats exactly where that mouse was running. 102 00:09:28,487 --> 00:09:33,003 Its pitch dark and the mouse clearly has no idea that the snake is there. 103 00:09:34,447 --> 00:09:37,086 But the snake is well aware of the mouse. 104 00:09:37,167 --> 00:09:40,125 Thanks no doubt to those heat-detecting pits. 105 00:09:44,287 --> 00:09:48,166 A snake strikes by suddenly straightening the curve in its neck. 106 00:09:48,247 --> 00:09:51,398 But at the moment the mouse is not within range. 107 00:10:02,887 --> 00:10:05,401 Hes worked out that that is the path 108 00:10:05,487 --> 00:10:08,399 along which the mice run 109 00:10:10,087 --> 00:10:12,920 and hes getting himself properly adjusted 110 00:10:13,687 --> 00:10:16,884 so he can strike it when he next gets a chance. 111 00:10:30,487 --> 00:10:33,160 Now once again waiting. 112 00:10:34,407 --> 00:10:36,875 Thats what snakes are so good at. 113 00:10:42,287 --> 00:10:43,686 (RUSTLING) 114 00:10:59,327 --> 00:11:00,646 (ATTENBOROUGH EXCLAIMS) 115 00:11:01,007 --> 00:11:02,599 Oh my goodness. 116 00:11:07,607 --> 00:11:09,723 Thats a dead mouse all right. 117 00:11:12,327 --> 00:11:13,965 Slow down that shot 118 00:11:14,047 --> 00:11:17,642 and you can see that the snake stabs the mouse just once. 119 00:11:19,727 --> 00:11:23,083 After three convulsive kicks the mouse is dead. 120 00:11:30,127 --> 00:11:31,958 The snake is moving again. 121 00:11:33,647 --> 00:11:38,243 Hes going back now to look for the one that 122 00:11:39,007 --> 00:11:41,840 he knows is dead back there. 123 00:11:43,487 --> 00:11:44,476 Where is it? 124 00:11:47,927 --> 00:11:50,919 Ah. Now it looks as though hes really got it. 125 00:11:55,647 --> 00:12:00,437 Thats his dinner and that can last him for 126 00:12:02,087 --> 00:12:04,681 three weeks four weeks if necessary. 127 00:12:13,967 --> 00:12:17,755 Rattlesnakes are among the least obtrusive inhabitants of the forests 128 00:12:17,847 --> 00:12:21,476 of North America and they are probably far more numerous 129 00:12:21,567 --> 00:12:23,558 than many people realise. 130 00:12:25,967 --> 00:12:28,959 Like many other animals snakes use their nostrils 131 00:12:29,047 --> 00:12:30,560 to detect smells. 132 00:12:30,647 --> 00:12:32,922 But the most sensitive and accurate information 133 00:12:33,007 --> 00:12:37,444 about the world around them comes from that constantly flickering tongue. 134 00:12:47,887 --> 00:12:52,358 With this a snake gathers molecules from the air and carries them back 135 00:12:52,447 --> 00:12:56,122 for evaluation to a pair of extremely sensitive organs 136 00:12:56,207 --> 00:12:58,277 in the roof of its mouth. 137 00:12:59,407 --> 00:13:03,286 To see of just how important scent can be to a snake 138 00:13:03,367 --> 00:13:07,804 Ive come here to Carnac Island just off the coast of Western Australia. 139 00:13:08,607 --> 00:13:14,000 Its home to a large population of highly venomous tiger snakes. 140 00:13:16,727 --> 00:13:20,003 Snakes have been established here for many years 141 00:13:20,087 --> 00:13:23,875 but theres something odd about this particular population. 142 00:13:24,527 --> 00:13:27,405 Many of them have damaged heads 143 00:13:27,487 --> 00:13:31,799 and some of them are actually blind like this one. 144 00:13:31,887 --> 00:13:35,482 And yet puzzlingly in spite of the fact 145 00:13:35,567 --> 00:13:39,162 that theyre blind they all appear to be very well fed. 146 00:13:39,927 --> 00:13:44,398 So how do their heads get damaged? And how in that condition 147 00:13:44,487 --> 00:13:48,799 when they cant see anything can they catch all the prey they need? 148 00:13:51,887 --> 00:13:53,320 (GULLS CAWING) 149 00:13:53,407 --> 00:13:57,161 The snakes of course are not the only inhabitants of the island. 150 00:13:57,247 --> 00:14:00,717 Its also home for a large colony of silver gulls. 151 00:14:03,327 --> 00:14:08,082 The gulls breed throughout the year so their chicks are a source of food 152 00:14:08,167 --> 00:14:10,476 for the snakes that never ends. 153 00:14:14,927 --> 00:14:18,158 In fact the snakes eat pretty well nothing else. 154 00:14:23,127 --> 00:14:25,960 But the snakes dont get it all their own way. 155 00:14:26,047 --> 00:14:30,040 The gulls are valiant defenders of their nests and their chicks. 156 00:14:35,367 --> 00:14:39,076 Their stabbing beaks are powerful sharp and strong. 157 00:14:39,167 --> 00:14:42,318 And the gulls always go for the snakes head. 158 00:15:06,647 --> 00:15:10,003 One in 1 0 of the snakes are totally blinded. 159 00:15:11,367 --> 00:15:14,120 Tiger snakes dont have those heat-sensitive pits 160 00:15:14,207 --> 00:15:17,324 that rattlesnakes have so these blinded hunters 161 00:15:17,407 --> 00:15:20,444 must be guided entirely by their forked tongue. 162 00:15:21,407 --> 00:15:24,763 Its a superb direction-finding device. 163 00:15:25,327 --> 00:15:28,399 The snake can measure the strength of a smell separately 164 00:15:28,487 --> 00:15:31,763 on each of the two forks of its tongue. 165 00:15:31,847 --> 00:15:36,318 And if it wishes to follow up a smell then it simply detects 166 00:15:36,407 --> 00:15:40,320 the one that has the stronger smell and goes in that direction. 167 00:15:44,647 --> 00:15:48,526 Gull chicks are an ideal prey for a blinded snake 168 00:15:48,607 --> 00:15:51,883 because they are programmed to stay on their nests. 169 00:16:08,607 --> 00:16:12,805 Once a snake has located it a chick is doomed. 170 00:16:18,807 --> 00:16:22,243 Snakes it must be admitted have had a bad reputation 171 00:16:22,327 --> 00:16:25,046 ever since one appeared in the Garden of Eden. 172 00:16:25,127 --> 00:16:29,120 But in reality even the most aggressive venomous snake 173 00:16:29,207 --> 00:16:32,040 will avoid biting a human being if it can. 174 00:16:32,687 --> 00:16:36,362 Why waste venom and risk violent retribution 175 00:16:36,447 --> 00:16:38,677 by biting something youre not going to eat? 176 00:16:41,167 --> 00:16:45,399 To prevent misunderstanding most venomous snakes warn other animals 177 00:16:45,487 --> 00:16:48,638 including human beings to keep out of their way. 178 00:16:48,767 --> 00:16:49,756 (HISSING) 179 00:16:49,847 --> 00:16:51,200 (RATTLING) 180 00:16:52,127 --> 00:16:53,879 Some snakes do that with sound. 181 00:16:53,967 --> 00:16:55,161 (RATTLING) 182 00:17:00,887 --> 00:17:02,206 (HISSING) 183 00:17:05,767 --> 00:17:08,839 Others such as cobras give a visual signal 184 00:17:09,247 --> 00:17:13,399 by expanding the skin around their heads to form a conspicuous hood. 185 00:17:16,527 --> 00:17:19,917 The threat of a bite is far better defence for a snake 186 00:17:20,007 --> 00:17:21,486 than the bite itself. 187 00:17:24,287 --> 00:17:26,926 However there are some snakes 188 00:17:27,487 --> 00:17:30,638 that not only use their venom to kill their prey 189 00:17:31,407 --> 00:17:36,845 but have also found a way of using it to deter their enemies 190 00:17:37,527 --> 00:17:39,279 without even biting them. 191 00:17:41,767 --> 00:17:45,885 This Mozambique cobra has a very special way of doing that. 192 00:17:49,287 --> 00:17:51,642 To demonstrate this with some degree of safety 193 00:17:51,727 --> 00:17:55,242 Im going to wear this visor which has been coated with a substance 194 00:17:55,327 --> 00:17:58,000 that turns pink in contact with venom. 195 00:17:58,967 --> 00:18:00,844 Lets see what happens. 196 00:18:04,487 --> 00:18:08,400 Its watching me waiting to see if I get too close for its liking. 197 00:18:18,287 --> 00:18:20,437 Venom spurts from its fangs. 198 00:18:21,927 --> 00:18:24,964 As it spits it turns its head from side to side 199 00:18:25,047 --> 00:18:28,403 so that the jets have the best chance of hitting my eyes. 200 00:18:32,847 --> 00:18:34,326 (SIGHING) 201 00:18:34,407 --> 00:18:37,160 Well I was well and truly sprayed. 202 00:18:38,087 --> 00:18:41,762 Every one of those pink dots is a bead of venom. 203 00:18:41,847 --> 00:18:45,999 And if any one of them had gone in my eye I would be now blind 204 00:18:46,087 --> 00:18:47,440 and in extreme pain. 205 00:18:47,527 --> 00:18:52,123 So its a fair warning from that snake to me not to get any closer. 206 00:18:52,207 --> 00:18:54,163 And I dare say if I did 207 00:18:54,247 --> 00:18:58,604 I would deserve what I would get which would be a bite. 208 00:18:58,687 --> 00:19:01,201 I have no intention of doing that. 209 00:19:03,207 --> 00:19:05,004 On the other hand some snakes 210 00:19:05,087 --> 00:19:09,558 which may appear to be venomous are in reality quite harmless. 211 00:19:12,047 --> 00:19:15,278 These two snakes look very very similar 212 00:19:15,967 --> 00:19:19,118 and they both occur here in the southern United States 213 00:19:19,207 --> 00:19:22,722 so you are quite likely to meet one or the other here. 214 00:19:23,607 --> 00:19:26,963 One of them however is harmless. Its called a kingsnake. 215 00:19:27,567 --> 00:19:29,762 The other one is a coral snake 216 00:19:29,847 --> 00:19:33,044 and highly venomous. One bite certain death. 217 00:19:33,967 --> 00:19:36,322 The question is which is which. 218 00:19:37,487 --> 00:19:41,958 Well the key lies in the order of the colour rings. 219 00:19:42,287 --> 00:19:48,123 People here have a local saying Red and black venom lack. 220 00:19:48,847 --> 00:19:52,203 Red and yellow can kill a fellow. 221 00:19:53,167 --> 00:19:58,036 And this one has red and black 222 00:19:59,087 --> 00:20:02,716 so I guess thats a kingsnake. 223 00:20:04,047 --> 00:20:05,321 Well see. 224 00:20:11,247 --> 00:20:14,922 So far so good. Yeah this is a kingsnake. 225 00:20:15,807 --> 00:20:18,196 And what a beautiful snake it is. 226 00:20:22,167 --> 00:20:24,123 A really lovely reptile. 227 00:20:31,047 --> 00:20:34,403 The kingsnake pretends to be venomous when its not. 228 00:20:35,047 --> 00:20:39,165 And theres another snake that pretends to be dead when it isnt. 229 00:20:44,167 --> 00:20:47,637 Snakes being cold-blooded seem to relish the warmth 230 00:20:47,727 --> 00:20:50,560 of sun-baked roads and often bask on them. 231 00:20:50,647 --> 00:20:53,639 And as a result of course many get run over. 232 00:20:59,047 --> 00:21:02,164 But things arent always exactly what they seem. 233 00:21:07,207 --> 00:21:09,880 He looks kind of dead 234 00:21:13,607 --> 00:21:17,395 but in fact this hog-nosed snake is perfectly all right. 235 00:21:21,487 --> 00:21:25,162 He was just feigning death 236 00:21:25,247 --> 00:21:30,605 so that things that might have been interested in a living snake are not. 237 00:21:30,687 --> 00:21:31,722 And whats more 238 00:21:31,807 --> 00:21:32,842 (SNIFFING) 239 00:21:32,927 --> 00:21:36,397 he has produced rather a remarkable smell. 240 00:21:37,167 --> 00:21:41,399 In fact the smell as it were of rotting flesh. 241 00:21:41,487 --> 00:21:45,799 So maybe he was pretending too that he was not only dead 242 00:21:45,887 --> 00:21:47,559 but decomposing. 243 00:21:48,247 --> 00:21:51,319 Very convincing. Off you go. 244 00:21:58,087 --> 00:22:01,966 The lack of limbs that might seem to us to be such a huge handicap 245 00:22:02,047 --> 00:22:05,517 has not stopped snakes from getting around in all kinds of ways 246 00:22:05,607 --> 00:22:09,566 and neither does it prevent them from tackling all kinds of meals. 247 00:22:11,287 --> 00:22:15,200 This South African snake has become a specialist in swallowing 248 00:22:15,287 --> 00:22:17,596 a particularly awkward mouthful. 249 00:22:21,967 --> 00:22:26,358 Its as accomplished a tree climber as youll find among snakes. 250 00:22:38,327 --> 00:22:41,603 The trees it frequents also hold colonies 251 00:22:41,687 --> 00:22:45,202 of masked weaverbirds that suspend their nests 252 00:22:45,287 --> 00:22:47,755 from the very tip of the branches. 253 00:22:47,847 --> 00:22:52,159 But the snake is a skilled enough climber to reach them. 254 00:22:52,247 --> 00:22:55,922 The weaverbirds know it well and recognise it as a threat. 255 00:22:56,007 --> 00:22:57,565 (CHIRPING) 256 00:23:06,247 --> 00:23:09,080 Its well accustomed to these attacks. 257 00:23:31,127 --> 00:23:34,722 These defenders however are just too determined 258 00:23:34,807 --> 00:23:36,445 and it retreats. 259 00:23:41,327 --> 00:23:43,795 But it doesnt give up altogether. 260 00:23:58,407 --> 00:24:01,126 This nest is unguarded. 261 00:24:05,847 --> 00:24:09,601 And this is what the snake is after the eggs. 262 00:24:09,687 --> 00:24:12,963 Each is several times bigger than the snakes head 263 00:24:13,127 --> 00:24:17,279 but its jaws are linked by ligaments that are amazingly elastic. 264 00:24:23,967 --> 00:24:26,925 Once the egg is engulfed by the snakes jaws 265 00:24:27,127 --> 00:24:29,846 powerful throat muscles push it down its gullet. 266 00:24:36,807 --> 00:24:40,641 Moving X-rays enable us to see exactly whats happening. 267 00:24:44,327 --> 00:24:47,637 Soon the egg reaches a part of the backbone 268 00:24:47,727 --> 00:24:50,480 that has downward pointing spines on it. 269 00:24:53,367 --> 00:24:56,723 The snake arches its backbone and then squeezes. 270 00:24:56,807 --> 00:24:58,160 (CRACKING) 271 00:25:01,247 --> 00:25:05,445 The shell cracks and the spines on the backbone slit the membrane. 272 00:25:09,247 --> 00:25:12,523 The shell is crushed and rich nutritious yolk 273 00:25:12,767 --> 00:25:14,837 flows into the snakes gut. 274 00:25:29,287 --> 00:25:32,484 Then whats left of the shell is regurgitated. 275 00:25:35,607 --> 00:25:38,075 But that of course was a small meal. 276 00:25:38,167 --> 00:25:42,046 Some snakes can tackle much bigger meals than that. 277 00:25:45,527 --> 00:25:48,837 An African rock python one of the biggest of all snakes 278 00:25:48,927 --> 00:25:52,363 that can grow over seven metres 20 feet long. 279 00:25:52,487 --> 00:25:55,479 And it is eating an antelope. 280 00:25:55,967 --> 00:26:00,119 It too has an elastic ligament connecting its jaws. 281 00:26:03,447 --> 00:26:06,086 It killed the antelope not with venom 282 00:26:06,167 --> 00:26:09,955 but by squeezing it so tightly that it was unable to breathe. 283 00:26:14,207 --> 00:26:17,279 A pythons teeth cant cut or rip. 284 00:26:17,367 --> 00:26:20,723 It has to swallow its prey whole or not at all. 285 00:26:20,807 --> 00:26:23,275 And that may take a day or more. 286 00:26:25,047 --> 00:26:28,642 Without limbs the python cant push the antelope down its throat. 287 00:26:29,487 --> 00:26:33,116 Instead it hitches its jaws diagonally back and forth 288 00:26:33,567 --> 00:26:38,163 so that they as it were walk along and over the prey. 289 00:26:39,367 --> 00:26:43,679 Its tube-like body has to stretch so extremely to accommodate 290 00:26:43,807 --> 00:26:47,038 such a gigantic meal that its flanks have torn. 291 00:26:47,567 --> 00:26:50,081 But such injuries heal very quickly. 292 00:26:55,247 --> 00:26:59,035 The last of the antelope its hooves are about to disappear. 293 00:27:07,727 --> 00:27:08,842 Gone. 294 00:27:15,767 --> 00:27:20,966 The python will now hide itself away and begin the long process of digestion. 295 00:27:21,407 --> 00:27:27,164 Everything will be dissolved skin hair hooves even horns. 296 00:27:35,007 --> 00:27:39,364 This python will not need to eat again for a year or more. 297 00:27:45,647 --> 00:27:48,957 Wherever its warm and there are animals of some kind 298 00:27:49,047 --> 00:27:50,799 there will be snakes to hunt them 299 00:27:50,887 --> 00:27:54,926 no matter how difficult the conditions and how awkward the mouthful. 300 00:27:56,927 --> 00:28:00,044 Crabs are in plentiful supply in this mangrove swamp. 301 00:28:00,127 --> 00:28:03,483 There must be 20 on any one of these trees around me. 302 00:28:03,567 --> 00:28:06,559 Theyre all up there waiting for the tide to go out 303 00:28:06,647 --> 00:28:09,366 so that they can feed in the mud below. 304 00:28:10,047 --> 00:28:15,838 So there is a meal for a snake here but crabs are not easy to tackle. 305 00:28:16,327 --> 00:28:20,479 Theyre strong armour-plated and covered in spines. 306 00:28:20,727 --> 00:28:26,245 For a snake to tackle one of these would be like me trying to eat a lobster 307 00:28:26,327 --> 00:28:30,161 twice the size of my head with my hands tied behind my back. 308 00:28:30,647 --> 00:28:33,684 But there is a snake that knows how to do so. 309 00:28:35,407 --> 00:28:38,604 The crabs cling to the arching struts of the mangroves 310 00:28:38,687 --> 00:28:41,201 to keep out of the way of predatory fish 311 00:28:41,287 --> 00:28:45,041 but as the tide retreats it becomes safe for them to climb down 312 00:28:45,127 --> 00:28:49,882 and start looking for such edible bits as the tide has left behind on the mud. 313 00:28:58,487 --> 00:29:00,557 For the moment theyre safe 314 00:29:00,647 --> 00:29:03,002 but soon the sun will set. 315 00:29:03,087 --> 00:29:05,965 Then the snakes will come out of their burrows. 316 00:29:06,687 --> 00:29:08,962 They hunt in the darkness 317 00:29:09,047 --> 00:29:12,676 but well be able to follow them with our infrared cameras. 318 00:29:21,007 --> 00:29:23,680 Its now very dark indeed 319 00:29:23,767 --> 00:29:28,522 and the snake has to find its way around entirely by touch and smell. 320 00:29:38,727 --> 00:29:41,002 Finding crabs is not difficult. 321 00:29:41,407 --> 00:29:42,886 They swarm all over the mud 322 00:29:42,967 --> 00:29:47,358 and the snake is almost bound to encounter one sooner rather than later. 323 00:29:55,607 --> 00:29:59,520 The snake is armed with venom and has short strong fangs 324 00:29:59,647 --> 00:30:02,525 which can pierce a crabs shell and stun it. 325 00:30:02,647 --> 00:30:04,683 But that is only half the problem. 326 00:30:04,767 --> 00:30:07,406 Its what it does after it has caught its crab 327 00:30:07,487 --> 00:30:10,240 that sets it apart from all other snakes. 328 00:30:36,767 --> 00:30:41,966 It has it. Now what? The crab is so large that the snake 329 00:30:42,047 --> 00:30:44,356 cant swallow it whole. 330 00:30:44,447 --> 00:30:49,123 Slowly and deliberately the snake dismembers the crab. 331 00:30:53,567 --> 00:30:56,365 Each leg contains nutritious muscle. 332 00:31:05,767 --> 00:31:11,080 But the crabs armoured body is simply discarded. Too difficult. 333 00:31:15,407 --> 00:31:19,286 There are hard-shelled creatures in fresh waters as well as in salt. 334 00:31:19,367 --> 00:31:22,677 Not nearly as many but sufficient number for some snakes 335 00:31:22,767 --> 00:31:24,962 to specialise in eating them. 336 00:31:27,287 --> 00:31:29,596 And in the eastern United States 337 00:31:29,687 --> 00:31:31,962 many rivers contain crayfish. 338 00:31:36,207 --> 00:31:39,165 Like crabs they have a hard protective shell 339 00:31:39,887 --> 00:31:43,277 and they have particularly powerful pincers as well. 340 00:31:50,927 --> 00:31:55,478 The queen snake however eats crayfish and nothing else. 341 00:32:15,287 --> 00:32:17,482 But not just any crayfish. 342 00:32:22,727 --> 00:32:24,479 Its very selective. 343 00:32:26,247 --> 00:32:29,398 Crayfish as they grow shed their armour. 344 00:32:33,207 --> 00:32:37,644 Every three to four weeks a split appears across the back of its shell. 345 00:32:41,247 --> 00:32:45,240 The old shell hinges away and the crayfish hauls itself out 346 00:32:45,327 --> 00:32:47,887 and expands its body which is soft. 347 00:32:50,327 --> 00:32:53,080 Its now that the snake has its chance. 348 00:33:04,487 --> 00:33:07,718 A newly moulted crayfish looks much the same 349 00:33:07,807 --> 00:33:09,923 but it gives off different chemicals 350 00:33:10,007 --> 00:33:13,079 that the snake can detect in the water with its tongue 351 00:33:13,167 --> 00:33:15,362 and from some distance away. 352 00:33:33,487 --> 00:33:37,765 It can swallow this crayfish because since it is newly moulted 353 00:33:38,447 --> 00:33:40,677 its as soft as a boiled egg. 354 00:34:05,647 --> 00:34:08,286 On occasion snakes have to grapple 355 00:34:08,367 --> 00:34:11,325 not only with their prey but with one another 356 00:34:11,407 --> 00:34:14,046 in disputes over mates and territory. 357 00:34:16,087 --> 00:34:19,318 This is one of the most formidable the king cobra. 358 00:34:19,407 --> 00:34:23,320 Highly venomous and about four metres 1 4 feet long. 359 00:34:26,007 --> 00:34:31,127 Disputes between rival male king cobras are potentially very dangerous indeed 360 00:34:31,847 --> 00:34:36,238 for this species specialises in eating other kinds of snakes. 361 00:34:38,967 --> 00:34:41,686 So they observe strict rules in their fights 362 00:34:41,767 --> 00:34:44,679 which prohibit the use of their lethal bite. 363 00:34:49,287 --> 00:34:52,359 Slowed down its a performance full of grace 364 00:34:52,767 --> 00:34:56,476 as each contestant strives not to kill his opponent 365 00:34:56,567 --> 00:34:59,161 but simply to slam him to the ground. 366 00:35:57,047 --> 00:36:00,926 The defeated male leaves the arena and no harm has been done. 367 00:36:09,247 --> 00:36:12,876 Snakes must also find a way of preventing their courtship 368 00:36:12,967 --> 00:36:14,923 from becoming lethal. 369 00:36:15,007 --> 00:36:18,397 This is a Californian kingsnake a male. 370 00:36:22,487 --> 00:36:25,797 He has detected the scent of a female ready to mate. 371 00:36:30,607 --> 00:36:33,599 Like all snakes his eyesight is not good 372 00:36:34,327 --> 00:36:38,320 but he can tell from the taste of the air that she is close by. 373 00:36:43,847 --> 00:36:46,486 In fact she is within inches. 374 00:37:09,687 --> 00:37:14,078 For some time the two follow one another nose to tail. 375 00:37:21,047 --> 00:37:23,561 The male begins to caress her 376 00:37:23,647 --> 00:37:27,799 sensually jerking and rocking his body as he holds her close. 377 00:37:32,087 --> 00:37:37,400 He has a pair of sexual organs one of which can project to the left 378 00:37:37,487 --> 00:37:39,125 and the other to the right. 379 00:37:39,207 --> 00:37:42,517 So no matter which side of him she happens to lie 380 00:37:43,047 --> 00:37:45,163 he can reach her. 381 00:37:47,367 --> 00:37:49,483 At last union is achieved. 382 00:38:07,767 --> 00:38:10,645 They may remain together for several hours. 383 00:38:28,447 --> 00:38:32,235 In a few weeks time the female will lay a clutch of eggs. 384 00:38:32,967 --> 00:38:36,198 It may take six or seven weeks for them to hatch 385 00:38:36,287 --> 00:38:38,755 but the regions where most snakes live are warm enough 386 00:38:38,847 --> 00:38:42,123 for them to develop without any help from the parents. 387 00:38:46,327 --> 00:38:49,637 Cobras lay them on the ground in the leaf litter. 388 00:38:58,247 --> 00:39:03,241 Their soft parchment-like shell is easily split when pushed from within. 389 00:39:11,607 --> 00:39:15,919 The front end of a cobra hatchling is quite capable of giving a bite 390 00:39:16,007 --> 00:39:19,238 even while the back end is still within the shell. 391 00:39:36,327 --> 00:39:40,798 Their fangs may be small but since it only takes a tiny drop of cobra venom 392 00:39:40,887 --> 00:39:45,961 to kill an animal these youngsters can be as lethal as their parents. 393 00:40:09,967 --> 00:40:14,006 They already have that characteristic warning signal the hood. 394 00:40:18,047 --> 00:40:22,563 Not all snakes lay their eggs. In some species 395 00:40:22,647 --> 00:40:26,526 the female retains them within her body until theyre ready to hatch 396 00:40:26,607 --> 00:40:29,326 so she gives birth to live young. 397 00:40:32,367 --> 00:40:34,801 The marshes of northern Argentina 398 00:40:35,327 --> 00:40:39,525 home to one of the largest of live-bearing snakes the anaconda. 399 00:40:46,727 --> 00:40:50,515 This is a female and shes heavily pregnant. 400 00:40:58,247 --> 00:41:00,317 Its morning and shes chilly 401 00:41:00,407 --> 00:41:04,036 so she moves out of the water and onto the swamp 402 00:41:04,127 --> 00:41:05,879 to warm herself in the sun. 403 00:41:20,127 --> 00:41:23,278 Slowly the day begins to warm up. 404 00:41:35,407 --> 00:41:38,763 Now its getting a little too hot for her 405 00:41:38,847 --> 00:41:42,237 so she moves back to the water to cool off. 406 00:41:45,127 --> 00:41:50,804 In this way she manages to keep her body close to 29 degrees centigrade 407 00:41:50,887 --> 00:41:54,163 perfect for the babies developing within her. 408 00:42:01,127 --> 00:42:03,846 But she wont give birth here and now. 409 00:42:04,447 --> 00:42:06,438 There are caiman around. 410 00:42:12,407 --> 00:42:16,116 At last she finds the quiet pool that she needs. 411 00:42:18,727 --> 00:42:20,843 And her contractions start. 412 00:42:49,007 --> 00:42:51,919 The first of her babies has arrived. 413 00:42:56,007 --> 00:42:59,966 Up it goes to the surface to take its first breath of air. 414 00:43:07,367 --> 00:43:09,835 But there are more babies to come. 415 00:43:28,367 --> 00:43:30,927 Eventually she produces 1 2. 416 00:43:31,567 --> 00:43:34,718 In fact thats quite modest for an anaconda. 417 00:43:34,807 --> 00:43:36,923 They can produce up to 40. 418 00:43:38,407 --> 00:43:42,320 Right from the beginning of their lives theyre totally independent 419 00:43:42,407 --> 00:43:45,126 and get no care or protection from their mother. 420 00:43:47,847 --> 00:43:52,557 The anaconda spends so much of its time in water and is such a powerful swimmer 421 00:43:52,647 --> 00:43:55,480 that it can be properly considered aquatic. 422 00:44:00,447 --> 00:44:04,122 Snakes have become adapted to almost every environment 423 00:44:04,207 --> 00:44:08,041 including even the sea as this one has. 424 00:44:08,847 --> 00:44:13,398 It doesnt often bite but it does have an extremely powerful venom 425 00:44:13,487 --> 00:44:15,079 so I am not going to handle it. 426 00:44:15,167 --> 00:44:18,318 But I will help it a little with this stick. 427 00:44:18,727 --> 00:44:24,563 As you can see it has a very flattened paddle at the end of its tail. 428 00:44:25,567 --> 00:44:28,286 But on land its pretty helpless. 429 00:44:29,167 --> 00:44:34,241 However if I assist it in getting into the sea... 430 00:44:40,487 --> 00:44:42,876 And now its in its element. 431 00:44:46,367 --> 00:44:49,643 Sea snakes have had to modify many of the features 432 00:44:49,727 --> 00:44:53,879 that enabled their far distant ancestors to colonise the land. 433 00:44:53,967 --> 00:44:56,720 They still have a lung with which to breathe air 434 00:44:56,807 --> 00:45:00,004 like other snakes but they can also absorb oxygen 435 00:45:00,087 --> 00:45:02,601 from the seawater through their skin. 436 00:45:10,687 --> 00:45:13,838 Salt inevitably gets into a sea snakes body 437 00:45:13,927 --> 00:45:16,441 but the snake manages to get rid of that 438 00:45:16,527 --> 00:45:19,837 by excreting it from a gland under its tongue. 439 00:45:19,927 --> 00:45:22,361 It also needs to drink fresh water. 440 00:45:22,447 --> 00:45:26,520 So in calm seas it waits at the surface for rain. 441 00:45:28,207 --> 00:45:32,723 Sea snakes really are truly marine creatures. 442 00:45:32,807 --> 00:45:36,038 They can live out here in the open ocean 443 00:45:36,127 --> 00:45:40,006 and the only clue you have to their link with the land 444 00:45:40,087 --> 00:45:43,079 is that they have to come up every quarter of an hour or so 445 00:45:43,167 --> 00:45:44,725 for a gulp of air. 446 00:45:55,887 --> 00:46:00,199 Most sea snakes like this bar-bellied species hunt fish. 447 00:46:00,927 --> 00:46:03,646 They have one of the most lethal venoms known 448 00:46:03,727 --> 00:46:06,525 which kills almost instantaneously. 449 00:46:06,607 --> 00:46:10,520 And that is a very important quality if you hunt fast-swimming 450 00:46:10,607 --> 00:46:12,279 ocean-going prey. 451 00:46:13,407 --> 00:46:16,365 But paradoxically the most highly specialised 452 00:46:16,447 --> 00:46:19,644 sea snake of all has abandoned venom altogether. 453 00:46:22,207 --> 00:46:26,598 It has a beak like a turtle and a wholly different way of feeding. 454 00:46:41,447 --> 00:46:45,281 Reef fish dont like to have it around. They mob it. 455 00:46:56,527 --> 00:47:00,805 It doesnt even retaliate. Its not interested in them. 456 00:47:07,647 --> 00:47:09,319 Its after their eggs. 457 00:47:09,847 --> 00:47:13,760 These the fish have stuck to the stony branches of the coral. 458 00:47:19,527 --> 00:47:24,237 The snakes hardened turtle-like top lip enables it to scrape them off. 459 00:47:33,767 --> 00:47:38,204 Its such a slow-moving browser that algae and other small organisms 460 00:47:38,287 --> 00:47:41,677 grow on its skin as they do on the bottom of a boat. 461 00:47:47,167 --> 00:47:51,206 The loss of limbs could seem to be a handicap 462 00:47:51,287 --> 00:47:55,326 and certainly makes the snakes seem alien creatures to us. 463 00:47:56,127 --> 00:48:00,120 But it is that very loss that has enabled the snakes 464 00:48:00,207 --> 00:48:02,323 to colonise every environment 465 00:48:02,407 --> 00:48:04,602 from below the ground to above the ground 466 00:48:04,687 --> 00:48:08,726 from bushes to trees to the air and even to the sea. 467 00:48:09,607 --> 00:48:12,326 And it is that absence of limbs too 468 00:48:12,407 --> 00:48:17,003 which has enabled them to do it with such elegance and grace. 469 00:48:27,367 --> 00:48:31,076 Filming venomous snakes presented a lot of special problems 470 00:48:31,167 --> 00:48:33,397 to the Life in Cold Blood team 471 00:48:33,487 --> 00:48:37,799 but the toughest was trying to film a rattlesnake hunting in the wild. 472 00:48:38,967 --> 00:48:43,961 A rattlesnake making a kill has rarely even been seen and never before filmed 473 00:48:44,047 --> 00:48:45,719 and for several reasons. 474 00:48:45,807 --> 00:48:48,560 For one thing rattlesnakes are so well camouflaged 475 00:48:48,647 --> 00:48:51,115 theyre very difficult to find. 476 00:48:51,207 --> 00:48:53,357 We enlisted the help of snake expert 477 00:48:53,447 --> 00:48:55,278 Harry Greene and his team. 478 00:48:55,367 --> 00:48:58,006 Theyve been studying a group of timber rattlesnakes 479 00:48:58,087 --> 00:49:02,046 using radio telemetry which enables them to find their rattlesnakes 480 00:49:02,127 --> 00:49:04,641 at any time of day or night. 481 00:49:04,727 --> 00:49:08,402 Most of us will never find them and theyre superbly camouflaged. 482 00:49:08,487 --> 00:49:13,277 Exactly but thats been one of the wonderful things about radio telemetry 483 00:49:13,367 --> 00:49:15,801 is we can have an animal that we can dial up. 484 00:49:15,887 --> 00:49:17,764 ATTENBOROUGH: To have any chance of success 485 00:49:17,847 --> 00:49:21,157 the crew had to be able to find the rattlesnakes on their own. 486 00:49:21,247 --> 00:49:23,966 So producer James Brickell had to take a course 487 00:49:24,047 --> 00:49:26,163 in telemetry techniques himself. 488 00:49:26,247 --> 00:49:29,080 Hmm point it a little bit more this way. 489 00:49:29,167 --> 00:49:32,239 ATTENBOROUGH: Each snake has been implanted with a tiny transmitter. 490 00:49:32,327 --> 00:49:35,763 If you dial its frequency you can pick up a beeping sound. 491 00:49:35,847 --> 00:49:38,805 And that gets louder the nearer you get to the snake. 492 00:49:39,407 --> 00:49:41,523 (BEEPING) 493 00:49:44,567 --> 00:49:46,159 And so its just like if you were trying to find 494 00:49:46,247 --> 00:49:48,807 your favourite rock-and-roll station or something 495 00:49:48,887 --> 00:49:51,162 but now were gonna find our favourite rattlesnake. 496 00:49:51,247 --> 00:49:54,762 So you just punch in its number and its on the air. 497 00:49:54,847 --> 00:49:58,283 ATTENBOROUGH: It sounds simple in theory but theres a snag. 498 00:49:58,367 --> 00:49:59,641 (BEEPING) 499 00:50:01,287 --> 00:50:03,039 Its here somewhere. 500 00:50:03,927 --> 00:50:05,997 just be really careful guys. 501 00:50:06,087 --> 00:50:08,885 ATTENBOROUGH: In a forest the signal can bounce off trees 502 00:50:08,967 --> 00:50:11,561 and give you a false reading so that it can seem 503 00:50:11,647 --> 00:50:13,126 that the snake is everywhere. 504 00:50:13,207 --> 00:50:15,402 And you dont want to think a reading is false 505 00:50:15,487 --> 00:50:18,240 and then tread on your snake by mistake. 506 00:50:18,327 --> 00:50:19,316 Hes that way there? 507 00:50:19,407 --> 00:50:21,045 MAN: Youll find hes up there somewhere. 508 00:50:21,127 --> 00:50:22,765 Lets find him. 509 00:50:22,847 --> 00:50:24,405 james its starting to get dark. 510 00:50:24,487 --> 00:50:26,364 Yeah I know. Hes in there. I reckon hes hunting. 511 00:50:26,447 --> 00:50:27,675 MAN: James be careful where youre going. 512 00:50:27,767 --> 00:50:29,962 ATTENBOROUGH: And it isnt just the one snake youre tracking. 513 00:50:30,047 --> 00:50:33,676 There are dozens of others in the area that arent tagged. 514 00:50:33,767 --> 00:50:35,485 (BEEPING CONTINUES) 515 00:50:35,887 --> 00:50:38,560 MAN: Follow my hand. jAMES: There he is. 516 00:50:38,647 --> 00:50:40,683 Its about 20 feet. 517 00:50:40,767 --> 00:50:42,723 MAN: All right good. jAMES: Six metres. 518 00:50:42,807 --> 00:50:43,842 ATTENBOROUGH: And so at last 519 00:50:43,927 --> 00:50:47,806 the crew meet a very special snake called Hank. 520 00:50:53,127 --> 00:50:56,199 Hank is in a perfect position for his ambush. 521 00:50:56,287 --> 00:50:59,324 To film the action without disturbing him or his prey 522 00:50:59,407 --> 00:51:01,637 cameraman Mark MacEwen has fitted his camera 523 00:51:01,727 --> 00:51:04,924 with motion detectors from a burglar alarm. 524 00:51:05,007 --> 00:51:08,920 They will turn on the camera without anyone having to be there. 525 00:51:10,287 --> 00:51:15,281 So for the first time they set up their gear in front of a live snake. 526 00:51:16,567 --> 00:51:20,446 They could now leave Hank and track another of Harrys snakes. 527 00:51:21,847 --> 00:51:25,442 So that means you know individual snakes over a long period of time. 528 00:51:25,527 --> 00:51:27,040 Do they differ very much? 529 00:51:27,127 --> 00:51:28,765 Absolutely absolutely. 530 00:51:28,847 --> 00:51:31,759 Now there are species differences so certain rattlesnake species 531 00:51:31,847 --> 00:51:34,122 are more sort of nasty-tempered than others. 532 00:51:34,207 --> 00:51:39,281 But even within a population youll have one that just never gets riled up 533 00:51:39,367 --> 00:51:41,119 and one that you know you just cant get too close to 534 00:51:41,207 --> 00:51:42,845 without it getting upset. 535 00:51:43,767 --> 00:51:45,758 ATTENBOROUGH: With one camera set up on Hank 536 00:51:45,847 --> 00:51:48,202 james decides to track another snake 537 00:51:48,287 --> 00:51:51,962 and to do so in the dark which is when most rattlesnakes hunt. 538 00:51:52,047 --> 00:51:55,357 But in the pitch blackness there was a distinct possibility 539 00:51:55,447 --> 00:51:58,200 that James would accidentally get so close to the snake 540 00:51:58,287 --> 00:52:02,246 he was looking for he would step within striking distance. 541 00:52:02,327 --> 00:52:05,364 Quite unnerving if you havent done it before. 542 00:52:05,447 --> 00:52:06,800 (BEEPING) 543 00:52:09,927 --> 00:52:13,715 Its actually pretty dangerous walking around in the middle of the night 544 00:52:13,807 --> 00:52:16,605 trying to find a rattlesnake in these conditions. 545 00:52:22,687 --> 00:52:23,802 Hes really close. 546 00:52:23,887 --> 00:52:25,923 Its got to be here over near these logs. 547 00:52:26,007 --> 00:52:29,522 I think the snakes about probably five 1 0 metres away. 548 00:52:29,607 --> 00:52:32,485 It would be easier to find a needle in a haystack 549 00:52:34,087 --> 00:52:37,397 than to find a reptile that looks like a load of dead leaves 550 00:52:37,487 --> 00:52:40,160 in a huge pile of dead leaves. 551 00:52:40,247 --> 00:52:42,636 MARK ON RADIO: Have you found it, fellows? 552 00:52:42,727 --> 00:52:47,517 Negative Mark. Weve got to a huge pile of logs and wood. 553 00:52:47,607 --> 00:52:50,724 ATTENBOROUGH: The team decide to abandon tracking the second snake 554 00:52:50,807 --> 00:52:55,437 and instead check on the camera they had left on Hank in the afternoon. 555 00:52:55,527 --> 00:52:58,166 I think its too dangerous actually to go poking around in there 556 00:52:58,247 --> 00:53:00,522 and anyway you wouldnt be able to get the lights and the camera in. 557 00:53:00,607 --> 00:53:03,121 So were gonna wrap on it and come back. 558 00:53:03,367 --> 00:53:06,404 Weve seen things on your videos weve never seen before. 559 00:53:06,487 --> 00:53:07,715 -Really? -Which is kind of surprising. 560 00:53:07,807 --> 00:53:09,718 I mean weve watched snakes a lot. 561 00:53:09,807 --> 00:53:12,162 By we I mean all rattlesnake biologists 562 00:53:12,247 --> 00:53:16,160 and weve seen things on your videos we havent seen before. 563 00:53:16,247 --> 00:53:19,159 So I think its actually kind of exciting to think about 564 00:53:19,247 --> 00:53:22,045 how this kind of collaboration might really be a feedback 565 00:53:22,127 --> 00:53:24,960 between the media and the public and science and so forth. 566 00:53:25,807 --> 00:53:28,196 ATTENBOROUGH: And something very surprising had happened 567 00:53:28,287 --> 00:53:31,120 at our very first attempt and in broad daylight. 568 00:53:31,207 --> 00:53:34,005 A chipmunk had tripped the motion detectors 569 00:53:34,087 --> 00:53:37,477 and Hank makes a kill right in front of the cameras. 570 00:53:44,967 --> 00:53:45,956 -Weve got a strike. -We got him. 571 00:53:46,047 --> 00:53:48,242 -Already weve got it. -We got it. 572 00:53:48,327 --> 00:53:49,316 I thought you were winding me up. 573 00:53:49,407 --> 00:53:51,841 MAN: I was like James somethings happened here. 574 00:53:51,927 --> 00:53:54,236 I thought Well thats just a classic wind-up. 575 00:53:54,327 --> 00:53:56,283 First night to get that. 576 00:53:57,127 --> 00:53:59,687 ATTENBOROUGH: We hadnt got the eating shot but its a start. 577 00:53:59,767 --> 00:54:02,884 And then the camera is set off again by a second chipmunk 578 00:54:02,967 --> 00:54:04,525 behaving very strangely. 579 00:54:04,607 --> 00:54:07,883 We showed the recording to Harry and he was fascinated. 580 00:54:08,927 --> 00:54:10,485 HARRY: Now what was that chipmunk doing? 581 00:54:10,567 --> 00:54:13,559 Was it perceiving something that the other chipmunk left 582 00:54:13,647 --> 00:54:15,683 some kind of alarm odour or something? 583 00:54:15,767 --> 00:54:17,997 Was it perceiving the odour of the rattlesnake? 584 00:54:18,087 --> 00:54:20,760 Or was it something I cant even imagine yet? 585 00:54:20,847 --> 00:54:23,805 But something was going on there that I didnt know to expect anyway. 586 00:54:23,887 --> 00:54:25,002 And its in your film. 587 00:54:26,167 --> 00:54:28,806 ATTENBOROUGH: Hank could clearly be the star of the show 588 00:54:28,887 --> 00:54:32,118 so the crew decide to concentrate all their efforts on him 589 00:54:32,207 --> 00:54:35,244 and to track him for two weeks around the clock. 590 00:54:35,327 --> 00:54:37,716 They quickly learn that despite his ability 591 00:54:37,807 --> 00:54:41,595 to hurt one of them very seriously he seems pretty unconcerned. 592 00:54:41,687 --> 00:54:44,645 In fact he never even rattles a warning at them. 593 00:54:44,727 --> 00:54:46,638 (BEEPING) 594 00:54:46,727 --> 00:54:49,002 The more they get to know him the more they think 595 00:54:49,087 --> 00:54:51,885 theyve got a good chance of filming another hunt. 596 00:54:51,967 --> 00:54:53,798 But then there is a serious problem. 597 00:54:54,007 --> 00:54:57,238 NEWSCASTER: Its just been raining here non-stop for the past three days, 598 00:54:57,327 --> 00:54:59,636 and they say that Tuesday afternoons hard rainstorm 599 00:54:59,727 --> 00:55:01,877 was the straw that broke the camels back. 600 00:55:01,967 --> 00:55:04,083 ATTENBOROUGH: Just as things are looking so promising 601 00:55:04,167 --> 00:55:06,920 New York State has its worst floods for a decade 602 00:55:07,007 --> 00:55:09,441 and all filming comes to a standstill. 603 00:55:11,607 --> 00:55:13,962 As you can see the weather is awful. 604 00:55:14,047 --> 00:55:16,277 Wont affect the rattlesnake at all. Hes perfectly happy. 605 00:55:16,367 --> 00:55:18,676 Hell be sat down in here somewhere just waiting 606 00:55:18,767 --> 00:55:21,076 but it does affect the mammals. 607 00:55:21,167 --> 00:55:24,125 The chipmunks and the mice theyll just be hunkered down somewhere 608 00:55:24,207 --> 00:55:25,606 not doing anything very much. 609 00:55:25,687 --> 00:55:28,326 And it affects us but hell be fine. 610 00:55:28,407 --> 00:55:29,522 Its just we cant film anything 611 00:55:29,607 --> 00:55:31,438 so its just a matter of waiting now. 612 00:55:33,247 --> 00:55:36,205 ATTENBOROUGH: After tracking him in the rain for 1 0 days 613 00:55:36,287 --> 00:55:40,280 theres a break in the weather and Hank starts hunting again. 614 00:55:40,367 --> 00:55:44,201 He chooses a position for an ambush in a very accessible spot. 615 00:55:44,767 --> 00:55:47,839 The team has another chance to use their remote cameras 616 00:55:47,927 --> 00:55:51,397 this time operating in night vision. 617 00:55:51,487 --> 00:55:54,320 MAN: James just be careful where you come in. Dont go that way. 618 00:55:54,407 --> 00:55:56,238 I think thats the direction hes headed in. 619 00:55:56,327 --> 00:55:58,557 Youve got something have you? 620 00:55:59,407 --> 00:56:02,080 MAN: Mate weve got him hitting a mouse 621 00:56:02,167 --> 00:56:04,806 in the middle of frame and swallowing it. 622 00:56:05,327 --> 00:56:08,046 ATTENBOROUGH: This time they get more than the strike. 623 00:56:08,127 --> 00:56:12,200 This time Hank decides to eat his dinner very obligingly 624 00:56:12,287 --> 00:56:13,959 right in front of the camera. 625 00:56:14,847 --> 00:56:18,840 Mate that is the most incredible piece of behaviour you have ever seen. 626 00:56:19,367 --> 00:56:22,120 ATTENBOROUGH: So after two weeks and a lot of effort 627 00:56:22,207 --> 00:56:23,526 they succeed in capturing 628 00:56:23,607 --> 00:56:28,237 a crucial and intimate moment in the life of this very special snake. 629 00:56:28,887 --> 00:56:32,084 People dont automatically love snakes most of them dont. 630 00:56:32,167 --> 00:56:35,477 And yet if you can show them things about the lives of these animals 631 00:56:35,567 --> 00:56:37,683 that impress them with the fact these are animals 632 00:56:37,767 --> 00:56:40,201 with complex daily activities... 633 00:56:40,287 --> 00:56:41,515 These arent things that are waiting around 634 00:56:41,607 --> 00:56:43,757 for an opportunity to kill people. 635 00:56:43,847 --> 00:56:47,726 When you tell people things like that then they get drawn in. 636 00:56:47,807 --> 00:56:50,765 And hopefully when we show them your films theyll be drawn in. 637 00:56:50,847 --> 00:56:53,361 Well youve drawn me in. Thank you very much. 638 00:56:53,447 --> 00:56:54,436 HARRY: Pleasure. 639 00:56:55,167 --> 00:56:57,522 ATTENBOROUGH: And when I get to see the footage 640 00:56:57,607 --> 00:57:01,964 its fair to say that Im just as knocked sideways as the crew had been. 641 00:57:03,607 --> 00:57:05,165 (GASPING) Theres the mouse. 642 00:57:06,287 --> 00:57:07,276 (ATTENBOROUGH EXCLAIMS) 643 00:57:07,447 --> 00:57:08,926 Oh my goodness. 644 00:57:11,247 --> 00:57:12,316 Yes. 645 00:57:14,127 --> 00:57:16,243 Thats a dead mouse all right.