0:00:02 > 0:00:04- Welcome to my Nightmares of Nature. - HOWLING
0:00:07 > 0:00:08I'm Naomi Wilkinson.
0:00:08 > 0:00:10Argh!
0:00:10 > 0:00:14And I'm coming face to face with the nightmares of the animal world.
0:00:17 > 0:00:20The ones that make your spine tingle...
0:00:21 > 0:00:23..your heart beat faster...
0:00:23 > 0:00:25Ah! Ha-ha!
0:00:25 > 0:00:26..and your blood run cold.
0:00:29 > 0:00:31Are they truly terrifying?
0:00:31 > 0:00:33Ooh! Or is there a twist in the tail?
0:00:33 > 0:00:35Whee-hee!
0:00:35 > 0:00:39Come with me as I shine a light on wildlife's deepest, darkest secrets.
0:00:41 > 0:00:45And see if you can guess which will be my worst nightmare.
0:00:49 > 0:00:52'Throughout this series, I've come face-to-face
0:00:52 > 0:00:54'with a whole host of nightmares of nature.
0:00:57 > 0:01:00'In tracking them down, I've braved the darkness...'
0:01:00 > 0:01:01NAOMI GASPS
0:01:01 > 0:01:04Oh, I don't like that one!
0:01:04 > 0:01:05'..battled the big chill...'
0:01:05 > 0:01:08Oh-ho-ho-ho-ho!
0:01:08 > 0:01:12'..and submerged myself into a subterranean world.
0:01:14 > 0:01:17'And my trusty crew have put me through my paces
0:01:17 > 0:01:20'in an attempt to be like some of the animals I've met.'
0:01:20 > 0:01:23I cannot believe I'm going to be sleeping up here, this high!
0:01:23 > 0:01:28'But one thing's for certain, it's been a journey full of nightmares!'
0:01:28 > 0:01:29Oh-ho-ho-ho-ho!
0:01:29 > 0:01:30Yes. Ooh!
0:01:30 > 0:01:32'In this programme, I'll be counting down
0:01:32 > 0:01:36'through my top ten worst nightmares of the series
0:01:36 > 0:01:38'and revealing which one I have chosen
0:01:38 > 0:01:41'to take the top spot as my very worst.
0:01:44 > 0:01:47'Kicking off the countdown and in at number ten,
0:01:47 > 0:01:51'it's a primeval predator with a seriously snappy reputation.
0:01:54 > 0:01:58'The alligator snapping turtle.
0:01:58 > 0:02:02'I went out looking for them in the swamps of Florida
0:02:02 > 0:02:04'with wildlife expert, Jerry.
0:02:06 > 0:02:09'But I don't think I was prepared for what I was about to see.'
0:02:11 > 0:02:14I thought that was a turtle, but that's its head?
0:02:14 > 0:02:17This is what we were talking about.
0:02:17 > 0:02:21Oh! His head is as big as mine!
0:02:23 > 0:02:24Whoa! Look at that!
0:02:24 > 0:02:26Goodness me!
0:02:26 > 0:02:28- Oh, my gosh!- Wow!
0:02:28 > 0:02:32He is so prehistoric and like a big dinosaur.
0:02:32 > 0:02:35An angry one who's looking at me quite meanly.
0:02:35 > 0:02:37I'm going to back off a bit.
0:02:37 > 0:02:40'And I had every right to be fearful.
0:02:40 > 0:02:45'Alligator snapping turtles will snap at anything that moves.
0:02:45 > 0:02:49'Fish, birds, and reptiles are all on the menu.
0:02:49 > 0:02:53'Inside their mouth is a tongue that looks like a worm,
0:02:53 > 0:02:55'which the turtle uses as a lure.
0:02:55 > 0:02:58'Tempting prey right into its giant jaws
0:02:58 > 0:03:01'before snapping down with a powerful beak.'
0:03:04 > 0:03:07What damage can he do with his beak?
0:03:07 > 0:03:09Er...he could take your hand off.
0:03:10 > 0:03:13- Are you serious?- I'm dead serious.
0:03:14 > 0:03:17'They're crammed with nightmare credentials.
0:03:17 > 0:03:21'And having seen one of these titanic turtles in the flesh,
0:03:21 > 0:03:25'they're definitely snapping up my number ten.
0:03:26 > 0:03:28'Roaring into number nine,
0:03:28 > 0:03:31'it's the haunting howls of a mysterious mammal.
0:03:33 > 0:03:36'Which I heard deep in the jungles of Belize.'
0:03:36 > 0:03:38- FAINT HOWLING - (There, there! Can you hear that?)
0:03:40 > 0:03:42HOWLING
0:03:51 > 0:03:54Are we sure that dinosaurs are extinct?
0:03:54 > 0:03:57Because it sounds like there is a Tyrannosaurus rex in that tree.
0:04:00 > 0:04:02'Howler monkeys are thought to be
0:04:02 > 0:04:05'the loudest land mammal in the world.
0:04:07 > 0:04:10'These deep, resonating, guttural growls
0:04:10 > 0:04:15'are made as a clear sign to other troops to keep their distance.
0:04:19 > 0:04:22'And it wasn't until the sun rose in the jungle
0:04:22 > 0:04:26'I saw the animal responsible for this riotous racket.'
0:04:28 > 0:04:32HOWLING
0:04:36 > 0:04:38The level of the sound coming from
0:04:38 > 0:04:42just about five animals up there is unbelievable.
0:04:44 > 0:04:46It's a monkey.
0:04:46 > 0:04:48The calls of this monkey are so loud,
0:04:48 > 0:04:50they can be heard across the jungle
0:04:50 > 0:04:53from a distance of around two miles.
0:04:53 > 0:04:56And I think you can believe that, listening to this racket.
0:04:56 > 0:04:59They have a large pouch in their throats
0:04:59 > 0:05:01and a specially-modified voice box
0:05:01 > 0:05:06that allows them to amplify their voice!
0:05:06 > 0:05:08VOICE ECHOES
0:05:08 > 0:05:09A-hem!
0:05:09 > 0:05:11Not even sure how I did that.
0:05:15 > 0:05:19As warnings go, it's a pretty clear one.
0:05:19 > 0:05:22'So the haunting howls of this jungle dweller
0:05:22 > 0:05:26'make this loud-mouthed monkey a noisy number nine.
0:05:27 > 0:05:29'Battling it out for number eight,
0:05:29 > 0:05:33'it's the terrifying takeover of two alien invaders.
0:05:34 > 0:05:36'The North American bullfrog
0:05:36 > 0:05:40'versus the giant African land snail.
0:05:40 > 0:05:42'Both have an astronomical appetite,
0:05:42 > 0:05:46'but which one will eat up a place on my top ten list?
0:05:46 > 0:05:48'The first one under the spotlight
0:05:48 > 0:05:51'is the gluttonous giant African land snail.
0:05:53 > 0:05:56'It might sound like the plot from a science-fiction B-movie,
0:05:56 > 0:05:58'but in Florida's suburbs,
0:05:58 > 0:06:02'these escaped pets are munching their way through hundreds of plants
0:06:02 > 0:06:05'and even the plaster off people's walls.
0:06:08 > 0:06:10'So Richard Gaskalla and his team
0:06:10 > 0:06:12'are doing their best to control the problem.'
0:06:15 > 0:06:17It doesn't sound much, but it's a giant snail.
0:06:17 > 0:06:21It gets up to 20cm and can do a lot of damage.
0:06:22 > 0:06:26'So we really needed to track them down.'
0:06:26 > 0:06:28Here, here, here, here, here, here, here!
0:06:28 > 0:06:30Here, here, here, here, here!
0:06:32 > 0:06:35Snail! My first find!
0:06:35 > 0:06:37Ooh! And there's another one!
0:06:38 > 0:06:39Tiny little one hiding in there.
0:06:39 > 0:06:42So I've just found my first few snails.
0:06:42 > 0:06:46They don't look giant to me, they look tiny.
0:06:46 > 0:06:49Those are probably weeks to maybe a month old at best.
0:06:51 > 0:06:53'But back at snail defence HQ,
0:06:53 > 0:06:56'Richard wanted to introduce me to the real problem.'
0:06:58 > 0:07:00Richard, is this as big as they get?
0:07:00 > 0:07:04No. That's an adult snail, but they get about twice that size.
0:07:04 > 0:07:07- So they get very large.- Double that?
0:07:07 > 0:07:09I am very glad to be wearing these gloves
0:07:09 > 0:07:12because he/she is making a lot of slime.
0:07:12 > 0:07:17They are definitely slimy and leave a trail of slime
0:07:17 > 0:07:19and excrement wherever they go.
0:07:19 > 0:07:22So, it's not just slime, it's also their poo that's getting everywhere?
0:07:22 > 0:07:25- Yes. And nobody likes snail poo.- No.
0:07:26 > 0:07:29'So these giant invaders are no doubt a nightmare
0:07:29 > 0:07:32'and rampaging through the suburbs of Florida.
0:07:32 > 0:07:36'But in the UK, I encountered another nightmare invader
0:07:36 > 0:07:40'that could certainly rival it. The North American bullfrog.
0:07:41 > 0:07:44'It's a titanic terror that arrived on ships from America
0:07:44 > 0:07:47'hidden amongst garden pond plants.
0:07:47 > 0:07:51'And now populations are starting to pop up around the UK.
0:07:51 > 0:07:53'But with a voracious appetite
0:07:53 > 0:07:55'and not at all fussy about what they eat,
0:07:55 > 0:07:58'they're clearing out our garden ponds.
0:07:58 > 0:08:00'I joined up with Jonathan Cranfield,
0:08:00 > 0:08:04'who's been battling the bullfrog invasion.'
0:08:04 > 0:08:06Oh! You've got it! You've got it!
0:08:06 > 0:08:07Ooh, well done!
0:08:07 > 0:08:09My goodness, that's huge!
0:08:09 > 0:08:11That is huge!
0:08:11 > 0:08:13I can see why that is going to cause a problem
0:08:13 > 0:08:16for our own much smaller wildlife.
0:08:16 > 0:08:18So this is a bullfrog.
0:08:18 > 0:08:20You think this is a fully grown...?
0:08:20 > 0:08:23Fully-grown female bullfrog, yeah. It's in the wrong place.
0:08:23 > 0:08:26- If it was in the right place, it's not a problem.- Yeah.
0:08:26 > 0:08:28In the UK, we have isolated incidences
0:08:28 > 0:08:30of frogs being found in the countryside.
0:08:30 > 0:08:35We have found breeding populations over the last 20-odd years.
0:08:35 > 0:08:38And that's what's the concern, that they're out there
0:08:38 > 0:08:42and people not realising the big frog they see in their garden ponds
0:08:42 > 0:08:43isn't meant to be there.
0:08:43 > 0:08:49'With these frogs capable of laying up to 20,000 eggs at any one time,
0:08:49 > 0:08:52'this problem could quickly get out of hand,
0:08:52 > 0:08:55'turning into a totally terrifying takeover.
0:08:56 > 0:09:00'So the bullfrog may be a bully and a definite top ten contender,
0:09:00 > 0:09:04'but the relentless rampaging of the giant African land snail
0:09:04 > 0:09:06'has beaten it for me.
0:09:06 > 0:09:10'A massive mollusc that eats plants and plaster,
0:09:10 > 0:09:12'leaving a slimy trail of destruction
0:09:12 > 0:09:14'and poo wherever it goes.
0:09:14 > 0:09:18'Now, that certainly earns its nightmare place at number eight.
0:09:21 > 0:09:22'Sizing up seventh,
0:09:22 > 0:09:26'it's the most dangerous animal in Alaska's Anchorage.
0:09:26 > 0:09:29'It's the large, lumbering moose.
0:09:32 > 0:09:35'With around 300 to 500 wild moose living in Anchorage
0:09:35 > 0:09:39'alongside its human inhabitants, the chances of a run-in
0:09:39 > 0:09:42'with one of these massive mammals is pretty high.
0:09:42 > 0:09:45'As wildlife biologist Jesse and I found out.'
0:09:46 > 0:09:48- There he is!- Where, where? - In front of us.
0:09:48 > 0:09:50Ah! Look at it!
0:09:52 > 0:09:55- He's got big old antlers, hasn't he? - Yeah.
0:10:03 > 0:10:06'A male moose can weigh over half a tonne
0:10:06 > 0:10:09'and they use these lethal-looking weapons on their head
0:10:09 > 0:10:11'to do battle with each other.
0:10:13 > 0:10:16'So I was suddenly feeling really rather nervous
0:10:16 > 0:10:18'about being this close to one.
0:10:20 > 0:10:22'But Jesse wanted to take a closer look.'
0:10:22 > 0:10:24Oh, my goodness!
0:10:24 > 0:10:28'As this male had got himself in a bit of a tangle with a towrope.'
0:10:28 > 0:10:31Now he's starting to come towards us. Now where do we go?
0:10:31 > 0:10:33Come this way. No, this way, you guys, this way.
0:10:33 > 0:10:36This way. Steve, this way.
0:10:38 > 0:10:42Look at the size of him!
0:10:42 > 0:10:45- Yeah.- Those antlers are massive!
0:10:52 > 0:10:56'Male moose shed their antlers in the winter.
0:10:56 > 0:10:58'So although it may be a little annoying,
0:10:58 > 0:11:01'this bull will soon be free of his towrope.
0:11:01 > 0:11:04'Meaning Jesse's not worried about him at all.
0:11:04 > 0:11:06'Me, on the other hand...'
0:11:06 > 0:11:09I just feel so intimidated by an animal that size
0:11:09 > 0:11:12with antlers that big because you know they could do you such damage.
0:11:14 > 0:11:17If it doesn't want you there, just one little kick, ta-ta.
0:11:17 > 0:11:20'So an up-close encounter with a mammoth moose
0:11:20 > 0:11:23'sees it marching straight into seventh.'
0:11:25 > 0:11:30'Scuttling in at six, it's a whole host of spine-tingling arachnids.
0:11:31 > 0:11:33'I've certainly met my fair share
0:11:33 > 0:11:36'of eight-legged creatures throughout this series.
0:11:36 > 0:11:39'And been to the extremes to track them down.
0:11:39 > 0:11:41'I've been deep underground
0:11:41 > 0:11:44'to get a glimpse of a creepy cave-dwelling critter.'
0:11:44 > 0:11:47Ooh! Ooh, sorry. Sorry, sorry, sorry.
0:11:47 > 0:11:50They're so creepy! Ho-ho-ho-ho!
0:11:50 > 0:11:54'Headed deep into the desert to meet a tinsy-wincy spider
0:11:54 > 0:11:57'with a wheely clever talent.
0:11:58 > 0:12:01'And I've braved the darkness to trace a trio of terrors
0:12:01 > 0:12:04'in the Costa Rican jungle.'
0:12:04 > 0:12:06- Ah!- There it is!
0:12:06 > 0:12:09A trap door spider's home.
0:12:10 > 0:12:14'A spider that has a rather startling way of catching its prey.'
0:12:16 > 0:12:18When an insect walks on top of the door,
0:12:18 > 0:12:22the spider will feel the vibration.
0:12:22 > 0:12:25And it'll wait for the insect to walk off the door
0:12:25 > 0:12:28and right at that moment, the spider will leap out,
0:12:28 > 0:12:32grab the prey, pull it down into the home
0:12:32 > 0:12:34and there it will have dinner.
0:12:35 > 0:12:36'And unfortunately for me,
0:12:36 > 0:12:41'this jungle was teeming with plenty more spine-chilling spiders.'
0:12:41 > 0:12:44Oh, my word! Are you serious?!
0:12:44 > 0:12:47That's the biggest web I've ever, ever seen!
0:12:47 > 0:12:52'And this grand design was home to the golden orb spider.
0:12:52 > 0:12:55'A spider that uses its web to capture its prey
0:12:55 > 0:12:57'before delivering a deadly bite
0:12:57 > 0:12:59'and liquefying the unfortunate victim
0:12:59 > 0:13:02'and then sucking it up like a milkshake.
0:13:02 > 0:13:04'Eurgh!
0:13:04 > 0:13:06'And if that wasn't bad enough,
0:13:06 > 0:13:11'the final spider on my jungle jaunt was even worse.'
0:13:11 > 0:13:13Oh, I don't like that one!
0:13:14 > 0:13:17This is the Bolivian wandering spider.
0:13:17 > 0:13:21The venom is a neurotoxin, so it works very, very fast
0:13:21 > 0:13:25and it can put down, say, a tree frog in a matter of seconds.
0:13:28 > 0:13:30What would happen if we were bitten?
0:13:30 > 0:13:33It could be deadly within two to 12 hours of the bite.
0:13:33 > 0:13:35Whoa!
0:13:35 > 0:13:39'So even though my fear of spiders is starting to subside,
0:13:39 > 0:13:42'the contenders I've met throughout this series
0:13:42 > 0:13:44'have still sent a shiver down my spine.
0:13:44 > 0:13:46'And for that very reason,
0:13:46 > 0:13:49'these arachnids are scurrying into sixth position.
0:13:51 > 0:13:54'We've reached the halfway point of our countdown.
0:13:54 > 0:13:57'And so far, we've had one seriously snappy customer,
0:13:57 > 0:14:02'a very vocal primate that has a blood-curdling call,
0:14:02 > 0:14:05'a mammoth mollusc that's on the rampage,
0:14:05 > 0:14:09'a mighty mammal that's terrorising a town...
0:14:12 > 0:14:14'..and a stack of scary spiders.
0:14:14 > 0:14:18'Could anything be more of a nightmare?
0:14:18 > 0:14:22'Battling it out for our midway crown, we have two contenders
0:14:22 > 0:14:27'that look cute, but happen to be hiding some creepy credentials.
0:14:27 > 0:14:31'It's the peculiar peccary and the ominous oxpecker.
0:14:36 > 0:14:39'Flying in first is the oxpecker.
0:14:41 > 0:14:45'A beautiful bird I was foolishly looking forward to meeting.'
0:14:45 > 0:14:47Oh! They're quite cute, aren't they?
0:14:47 > 0:14:50Ian, I think you're going to have your work cut out
0:14:50 > 0:14:52trying to encourage me that these are a nightmare.
0:14:52 > 0:14:54They're so lovely!
0:14:54 > 0:14:57'But it was the revelations about what these pretty peckers do
0:14:57 > 0:15:00'that soon changed my opinion.'
0:15:00 > 0:15:04They are known in the softer-skinned animals to open up sores.
0:15:04 > 0:15:06And then they actually feed on
0:15:06 > 0:15:09little bits of flesh and blood that they can pull off.
0:15:09 > 0:15:12- They feed on blood?- Yeah.
0:15:14 > 0:15:19'In fact, these vampire-like birds have a tantalizing taste for it.
0:15:19 > 0:15:21'They get a lot of blood in their diet
0:15:21 > 0:15:23'from the engorged ticks that they eat,
0:15:23 > 0:15:26'but they also peck away at already-open wounds,
0:15:26 > 0:15:28'exposing the fresh blood below.
0:15:28 > 0:15:31'And they started to try it on us.'
0:15:33 > 0:15:36Ooh, he's going to draw blood. Ooh, no! He hasn't, has he?
0:15:36 > 0:15:39Oh, he has a little bit, there, look. He's drawn blood!
0:15:39 > 0:15:42Oh, no! He's drawn blood on your ear now! Do you want a handkerchief?
0:15:42 > 0:15:45It's fine. No, don't worry, I've got one.
0:15:45 > 0:15:47Oh! Did I say birds were my favourite?
0:15:47 > 0:15:50I'm changing my mind rapidly.
0:15:50 > 0:15:52'So the oxpecker is no doubt a nightmare,
0:15:52 > 0:15:56'but there's another crafty contender fishing for fifth place.
0:15:56 > 0:15:59'It's the peculiar peccary.
0:16:01 > 0:16:04'Who I met in Belize with zoo director, Sharon.
0:16:06 > 0:16:11'On first appearances, Chanelle looked like a harmless hog.'
0:16:11 > 0:16:14Look at your nose, it's fantastic!
0:16:14 > 0:16:17- Down, Chanelle.- It's like a dog, isn't it? Down, boy!
0:16:17 > 0:16:21'But this cute behaviour didn't last long.'
0:16:21 > 0:16:25Ooh, he's getting a bit cross now with us. Aaaahhh!
0:16:25 > 0:16:30Chanelle has suddenly changed attitude completely.
0:16:30 > 0:16:34'And when the rest of the herd turned up, things only got worse.'
0:16:34 > 0:16:37Oh-ho-ho!
0:16:37 > 0:16:38I'm glad I'm behind this fence.
0:16:38 > 0:16:40GRUNTING
0:16:41 > 0:16:43Ooh, scrap!
0:16:45 > 0:16:50Chanelle is letting them all know he is what we call the alpha male.
0:16:50 > 0:16:53'And he didn't particularly like our cameraman either.
0:16:56 > 0:16:59'But even though this feisty fur ball has a deceptive demeanour,
0:16:59 > 0:17:03'it's the oxpecker that has really flown into my nightmares.
0:17:04 > 0:17:08'A beautiful bird that eats ticks, parasites and blood
0:17:08 > 0:17:12'secures its place firmly in fifth.
0:17:13 > 0:17:18'Swimming into fourth is the cantankerous cape fur seal.
0:17:20 > 0:17:22'They may look sweet and innocent at first glance,
0:17:22 > 0:17:26'but cape fur seals have a seriously bad attitude
0:17:26 > 0:17:28'when it comes to getting on with each other.
0:17:28 > 0:17:30'During the mating season,
0:17:30 > 0:17:33'males fight fiercely over their territories.
0:17:35 > 0:17:37'These combats are fought chest to chest
0:17:37 > 0:17:40'and can inflict some serious injuries.
0:17:40 > 0:17:43'And their bad attitude never lets up.
0:17:43 > 0:17:47'Which local expert, Pieter, showed me on the beaches in Namibia.'
0:17:49 > 0:17:52It's hard to keep a track of what's going on where.
0:17:52 > 0:17:54Males roaring and sizing each other up.
0:17:54 > 0:17:58It's just...activity everywhere.
0:17:58 > 0:18:02It really is one big beach battle.
0:18:02 > 0:18:04You can see their teeth!
0:18:04 > 0:18:08I never would have thought they'd have teeth that size.
0:18:08 > 0:18:11It's quite frightening to be this close.
0:18:11 > 0:18:16'And even the tiny new pups were in the firing line of all this fury.'
0:18:16 > 0:18:19You can see those pups right in between these two males fighting.
0:18:19 > 0:18:23- How easily they could be in trouble. - Exactly, yeah.
0:18:23 > 0:18:26They just can't move out of the way fast enough, can they?
0:18:26 > 0:18:29These big males are totally focused on what they are doing.
0:18:29 > 0:18:32And in that process, 300-350kg of seal
0:18:32 > 0:18:37can move over a tiny little one and injure them, even kill them.
0:18:37 > 0:18:40'So their bolshie bad attitude sees the cape fur seal
0:18:40 > 0:18:42'fight its way into fourth.
0:18:45 > 0:18:49'With only three places left, what's made it onto my nightmare podium?
0:18:51 > 0:18:54'My trusty crew have thrown some pretty hairy challenges at me
0:18:54 > 0:18:57'throughout this series,
0:18:57 > 0:19:00'but two of them have really pushed me to the limits.'
0:19:00 > 0:19:02Oh! Come on, Naomi.
0:19:02 > 0:19:05'So it's a battle of endurance in at third.
0:19:05 > 0:19:07'And fighting it out for a place on the podium
0:19:07 > 0:19:11'is a terrifying night spent high up in the tree canopy
0:19:11 > 0:19:15'up against a chilling encounter in the crippling cold.
0:19:15 > 0:19:17'But which one will win the spot?'
0:19:19 > 0:19:21Pull it?
0:19:21 > 0:19:24'First up, it's the terrifying tree sleep.
0:19:26 > 0:19:31'To experience what it was like to sleep like a tent-making bat,
0:19:31 > 0:19:34'my crew arranged for me to sleep high up in the trees.'
0:19:37 > 0:19:40I cannot believe I'm going to be sleeping up here, this high!
0:19:40 > 0:19:42That's ridiculous!
0:19:43 > 0:19:48The...the reality of what we're about to do has just dawned on me.
0:19:48 > 0:19:53'And as night fell, my fears turned into nightmares.
0:19:53 > 0:19:55'And sleep became a distant memory.'
0:19:58 > 0:20:02ANIMAL AND BIRD CALLS
0:20:02 > 0:20:032:52.
0:20:03 > 0:20:09I've just been woken up by some very strange noises.
0:20:10 > 0:20:12A really creepy noise.
0:20:12 > 0:20:16GRUNTING
0:20:19 > 0:20:21I don't know what is making that noise.
0:20:23 > 0:20:26'So trying to sleep in a tree was suitably scary,
0:20:26 > 0:20:30'but braving the bitter cold could certainly rival it.'
0:20:34 > 0:20:36'In the winter months, animals in Alaska
0:20:36 > 0:20:40'have to withstand temperatures as low as -20 degrees Celsius.
0:20:42 > 0:20:44'Equivalent to living in a freezer.
0:20:44 > 0:20:48'So, what better way to experience their frozen world?'
0:20:51 > 0:20:53Just have a little look at the temperature I'm going into.
0:20:53 > 0:20:57Oh! -22 Celsius.
0:20:57 > 0:21:00'And, of course, to really feel it like the animals do,
0:21:00 > 0:21:04'I had to leave all my winter clothes outside.'
0:21:04 > 0:21:07- Here goes nothing.- All right. - After you.
0:21:07 > 0:21:09Oh, I can feel the cold already!
0:21:09 > 0:21:11- Yes.- A-a-a-a-a-ah!
0:21:11 > 0:21:13Yes.
0:21:15 > 0:21:16All right?
0:21:16 > 0:21:18'As the cold started to take effect,
0:21:18 > 0:21:23'medical expert, Maureen, set me some quite simple challenges.'
0:21:23 > 0:21:27Er...there!
0:21:27 > 0:21:28NAOMI LAUGHS
0:21:30 > 0:21:32Eight times eight?
0:21:33 > 0:21:35I know my eight times table!
0:21:35 > 0:21:37Eight...
0:21:37 > 0:21:40'But even these seemed too difficult to manage.'
0:21:40 > 0:21:43If I stayed in here a long time, what would happen to me eventually?
0:21:43 > 0:21:46- You will die.- OK. So, you would die?
0:21:46 > 0:21:47That's right.
0:21:47 > 0:21:52'So although a night spent at dizzy heights was truly terrifying,
0:21:52 > 0:21:56'life in a freezer would be far, far worse.
0:21:56 > 0:21:58'Temperatures that drop below -20
0:21:58 > 0:22:01'that could freeze my blood and stop my heart.
0:22:01 > 0:22:04'Now, that's a nightmare.
0:22:04 > 0:22:08'Clinching it for the cold and catapulting it into third.
0:22:11 > 0:22:13'Teaming up for second place,
0:22:13 > 0:22:15'it's the skilful hunt of the African wild dog.
0:22:21 > 0:22:25'Hunting in packs of up to 20 individuals, African wild dogs
0:22:25 > 0:22:29'are the most efficient large carnivores in Africa,
0:22:29 > 0:22:32'with over 80% of their hunts resulting in a kill.
0:22:33 > 0:22:37'Their success is down to incredible teamwork and co-operation.
0:22:40 > 0:22:43'And while I was out looking for them in Namibia with ranger, Tim,
0:22:43 > 0:22:46'I was privileged enough to see them in action.'
0:22:46 > 0:22:50Look at them all just stalking through the thicket, ears back!
0:22:52 > 0:22:54They've got a job to do, this lot.
0:22:57 > 0:22:59- There they go.- And they're off!
0:23:00 > 0:23:03'These determined dogs had their eye on an eland,
0:23:03 > 0:23:06'the largest antelope in Namibia.'
0:23:07 > 0:23:08- They've got it!- Have they?
0:23:08 > 0:23:12- They've got it.- They've taken it down. Yes, there it is, over there.
0:23:14 > 0:23:16NAOMI GASPS
0:23:26 > 0:23:29You can see how efficiently they did that.
0:23:29 > 0:23:32I'm sorry, I've never seen a kill before, so...
0:23:32 > 0:23:35- Um...it's a very emotional thing to watch.- Yeah.
0:23:35 > 0:23:38On the upside, you can see how skinny this animal is.
0:23:38 > 0:23:41And so it has been struggling
0:23:41 > 0:23:45throughout this dry season in the drought in Namibia.
0:23:45 > 0:23:48So it would most probably have died quite soon.
0:23:48 > 0:23:50The condition's very poor.
0:23:50 > 0:23:53And it's quite rough to see wild dogs do this,
0:23:53 > 0:23:55but it's going back into the ecosystem.
0:23:55 > 0:23:59- Instead of dying...- And being wasted.- ..and being wasted,
0:23:59 > 0:24:02it's feeding five little wild dog pups.
0:24:02 > 0:24:06'So a tactical takedown takes position two.
0:24:06 > 0:24:10'But if the hunt of the African wild dog wasn't my worst nightmare,
0:24:10 > 0:24:12'then what was?
0:24:14 > 0:24:17'It's time for my nightmare countdown.
0:24:17 > 0:24:22'Position ten was snapped up by the alligator snapping turtle.
0:24:22 > 0:24:26'Nipping in at nine, the haunting hollers of the howler monkey.
0:24:26 > 0:24:29'Eating up eighth, it's a mighty mollusc.
0:24:29 > 0:24:32'Charging into seventh, it's the mammoth moose.
0:24:32 > 0:24:36'Scurrying in at six, it's the eight-legged arachnids.
0:24:36 > 0:24:40'Flying into fifth is the outrageous oxpecker.
0:24:40 > 0:24:44'Fur is flying at four with the crabby cape fur seal.
0:24:44 > 0:24:47'Chilling out at three, it's the big freeze.
0:24:48 > 0:24:50'And it's a tactical takedown at two,
0:24:50 > 0:24:53'with the hunt of the African wild dog.
0:24:55 > 0:24:57'So, who is going to be my number one?
0:24:58 > 0:25:02'What will take the top spot as my worst nightmare of nature?
0:25:04 > 0:25:06'It's got to be...
0:25:06 > 0:25:08'3.5 tonnes of humungous,
0:25:08 > 0:25:12'aggressive, highly-territorial hippo!
0:25:16 > 0:25:19'One of the most aggressive animals in the world,
0:25:19 > 0:25:22'the hippo is responsible for killing more people in Africa
0:25:22 > 0:25:24'than any other large mammal.
0:25:25 > 0:25:27'Males are highly territorial
0:25:27 > 0:25:30'and defend their stretch of the river ruthlessly.
0:25:31 > 0:25:34'With their razor-sharp colossal canines,
0:25:34 > 0:25:37'they can inflict some serious damage.
0:25:39 > 0:25:44'And while I was in the waterways of South Africa with ranger, Stacey,
0:25:44 > 0:25:47'she certainly put this aggression in perspective.'
0:25:47 > 0:25:51You work with a lot of dangerous animals in your job, don't you?
0:25:51 > 0:25:54- Mm-hm.- Are you afraid of any of the animals?
0:25:54 > 0:25:55Hippos.
0:25:55 > 0:25:58- SNARLING - Did you hear that?
0:25:58 > 0:26:02Hippos can bite crocodiles of 3m in half.
0:26:05 > 0:26:07Right. OK. Hippos are well scary!
0:26:07 > 0:26:10You wouldn't want to mess with a hippo.
0:26:11 > 0:26:14'Hippos give little warning to their attack
0:26:14 > 0:26:17'and can charge in the water or on land.
0:26:17 > 0:26:20'And don't be fooled by their size.
0:26:20 > 0:26:25'These humungous hippos can reach speeds of up to 25mph.
0:26:28 > 0:26:30'Armed with all of these frightening facts,
0:26:30 > 0:26:32'my crew thought it would be a good idea
0:26:32 > 0:26:35'for me to come face-to-face with a rescued hippo.
0:26:38 > 0:26:42'And Jessica wasn't shy about introducing herself.'
0:26:42 > 0:26:45- Can you reach here?- Yes. Ooh!
0:26:45 > 0:26:51'Although this was close enough for me, Toni had other ideas.'
0:26:52 > 0:26:55Oh, good grief, look at the size of those teeth!
0:26:55 > 0:26:56- Like this? Yeah?- That's it.
0:26:56 > 0:26:59- Just keep on feeding.- Oh!
0:26:59 > 0:27:01I can't believe I am feeding a hippo.
0:27:01 > 0:27:04Yes, it's a great honour feeding her.
0:27:04 > 0:27:05She is a wild hippo.
0:27:05 > 0:27:09But you would never get this close to a wild hippo, would you?
0:27:09 > 0:27:11- Yes, you would. - Well, apart from Jessica.
0:27:11 > 0:27:13You won't live to tell the tale.
0:27:13 > 0:27:15LAUGHTER
0:27:16 > 0:27:19'And for that reason, hippos have to take the top spot.
0:27:20 > 0:27:22'Jessica may have been the exception,
0:27:22 > 0:27:24'but behind their endearing eyes,
0:27:24 > 0:27:27'hippos have a well-hidden temper.
0:27:27 > 0:27:31'Making this humungous, giant jouster
0:27:31 > 0:27:32'my worst nightmare.'
0:27:46 > 0:27:47How I arrive for the zoo!
0:27:47 > 0:27:49LAUGHTER