0:00:02 > 0:00:05This is... Deadly 360.
0:00:05 > 0:00:09We pit three of the deadliest predators against their prey.
0:00:10 > 0:00:16Examining their hunting strategies and escape tactics from every angle.
0:00:18 > 0:00:20By delving beneath the fur and the feathers,
0:00:20 > 0:00:23we find out why a hunt succeeds...
0:00:23 > 0:00:26and why they sometimes fail.
0:00:26 > 0:00:29One thing's certain, prey animals are anything but sitting ducks.
0:00:31 > 0:00:34Their defensive strategies keep them alive.
0:00:36 > 0:00:39And push predators to the limits.
0:00:40 > 0:00:42Prepare for Deadly 360.
0:00:44 > 0:00:48This is Deadly 360 Mission Control.
0:00:48 > 0:00:51Where all of today's action and analysis takes place.
0:00:53 > 0:00:56We have access to some of the most enthralling hunts
0:00:56 > 0:00:58ever caught on camera.
0:00:58 > 0:01:00I've recreated three of the most exciting
0:01:00 > 0:01:04and analysed them from a variety of different angles and perspectives
0:01:04 > 0:01:06in true 360-degree style.
0:01:08 > 0:01:11The predators we're looking at have to find and catch food,
0:01:11 > 0:01:12or they just won't make it.
0:01:12 > 0:01:15In the wild world, simply managing to survive
0:01:15 > 0:01:17is the greatest challenge of all.
0:01:17 > 0:01:20I present to you the Aerial Assassins.
0:01:20 > 0:01:22In today's line-up, we check out
0:01:22 > 0:01:25one of the fastest flying insects on the planet.
0:01:25 > 0:01:29The emperor dragonfly. An insect-chomping speedster.
0:01:29 > 0:01:32We also meet the Daubenton's bat.
0:01:32 > 0:01:36A nocturnal hunter who can detect prey in pitch black.
0:01:37 > 0:01:40And we'll check out how the kestrel uses its rock-steady vision
0:01:40 > 0:01:43to try and catch its prey.
0:01:43 > 0:01:45Three aerial assassins,
0:01:45 > 0:01:49three very different hunting strategies, all deadly.
0:01:53 > 0:01:56They look invincible, but there's a continual race going on in nature
0:01:56 > 0:01:59which ensures prey animals are always evolving
0:01:59 > 0:02:01spectacular ways of taking care of themselves.
0:02:04 > 0:02:09Trying to avoid their fluttering foes - the damselfly.
0:02:09 > 0:02:12Agile in flight, and an aerial acrobat.
0:02:12 > 0:02:15And this furry fellow, the field vole.
0:02:15 > 0:02:19An expert in staying hidden with a burst of speed to outrun its enemy.
0:02:19 > 0:02:22And the yellow underwing moth
0:02:22 > 0:02:27with its aeronautical tactics, which have to be seen to be believed.
0:02:27 > 0:02:29Three prey with three very different,
0:02:29 > 0:02:31but effective escape strategies.
0:02:32 > 0:02:35So, I've introduced you to all of our contenders,
0:02:35 > 0:02:39now it's time to meet our first deadly duo going head-to-head.
0:02:39 > 0:02:41This is the emperor dragonfly.
0:02:41 > 0:02:46The largest European dragonfly, and with a top speed of 35mph,
0:02:46 > 0:02:49one of the fastest insects in the world.
0:02:49 > 0:02:52And up against it is this -
0:02:52 > 0:02:55his smaller cousin, the damselfly.
0:02:55 > 0:02:59But which animal has the edge in the race for life?
0:02:59 > 0:03:02It's time to go Deadly 360.
0:03:06 > 0:03:08We witness the final stages of the hunt.
0:03:08 > 0:03:11The emperor dragonfly is lining up on the damselfly
0:03:11 > 0:03:13and chasing it down at top speed.
0:03:13 > 0:03:18But the damselfly has great vision and has spotted his attacker.
0:03:18 > 0:03:21It's twisting and turning, trying to escape,
0:03:21 > 0:03:24but the dragonfly is gaining.
0:03:24 > 0:03:28But even in a hunt like this, there are still lots of factors in play.
0:03:28 > 0:03:31And to find out why a predator might succeed or fail,
0:03:31 > 0:03:33we need to wind back the action
0:03:33 > 0:03:36and build up the entire hunt right from the beginning.
0:03:38 > 0:03:42This battle takes place in southern France.
0:03:42 > 0:03:45And more specifically, on a stretch of river here,
0:03:45 > 0:03:48beside the vast grounds of a castle.
0:03:48 > 0:03:50Quite fitting for an emperor.
0:03:50 > 0:03:53Water is absolutely critical for the dragonfly.
0:03:53 > 0:03:56As where there's water, there are many insects to feast on.
0:03:56 > 0:04:00And one of the largest potential meals here is the damsel fly.
0:04:00 > 0:04:04But they're also the most difficult to catch.
0:04:04 > 0:04:07So, that's the arena for our gladiatorial contest.
0:04:07 > 0:04:11What weapons and defences do the two animals doing battle have?
0:04:14 > 0:04:16Well, the emperor dragonfly's chief ability
0:04:16 > 0:04:20is flying at incredible speeds of over 35mph.
0:04:20 > 0:04:23But they also have extraordinary vision.
0:04:23 > 0:04:28And chomping jaws to despatch their prey in seconds.
0:04:29 > 0:04:33All of this makes our predator a pretty scary prospect.
0:04:33 > 0:04:36What does our prey animal have to counter?
0:04:36 > 0:04:38Damselflies are also hunters,
0:04:38 > 0:04:41so have similar weapons to the dragonfly.
0:04:41 > 0:04:44But today, they'll need those weapons for defence.
0:04:44 > 0:04:48Their vision enables them to see nearly 360 degrees.
0:04:48 > 0:04:52They can also hit some superfast speeds through the air themselves,
0:04:52 > 0:04:56and they're nimble, able to twist and turn their way out of danger.
0:04:57 > 0:05:00With two such talented animals,
0:05:00 > 0:05:04this hunt is going to be a close-run thing. Let's see what happens.
0:05:06 > 0:05:09The sun has only just come up and it's cold,
0:05:09 > 0:05:12so the first thing the emperor dragonfly does is sunbathe,
0:05:12 > 0:05:14while shivering its flight muscles.
0:05:14 > 0:05:19It needs to warm these muscles up before it can take off.
0:05:19 > 0:05:22The damselflies are smaller than the dragonfly
0:05:22 > 0:05:25and can warm up their flight muscles faster,
0:05:25 > 0:05:26therefore get going earlier.
0:05:26 > 0:05:29That gives them a real headstart over the dragonfly.
0:05:29 > 0:05:31So let's catch up with what they're up to.
0:05:31 > 0:05:36It's the damselfly breeding season. This male tries to impress his girl.
0:05:36 > 0:05:40But there are others trying to get her attention. Time for a battle.
0:05:40 > 0:05:44But a gentlemanly one, involving synchronised ballet.
0:05:44 > 0:05:47The most agile flier has the best flight muscles.
0:05:47 > 0:05:49Something the female wants to pass on to her offspring
0:05:49 > 0:05:52to give them the best chance of survival.
0:05:52 > 0:05:55This battle may look like a simple bit of flying,
0:05:55 > 0:06:00but it's extremely tiring work and requires his undivided attention.
0:06:00 > 0:06:04Our emperor dragonfly is nearly at optimum temperature.
0:06:04 > 0:06:07He's warming up his flight muscles and almost ready to fly.
0:06:07 > 0:06:11And when he does, he'll have a whole host of weapons at his disposal.
0:06:11 > 0:06:13Let's check them out here in Deadly HQ.
0:06:15 > 0:06:18So, this is an emperor dragonfly.
0:06:18 > 0:06:21It's the largest species of dragonfly found in Europe,
0:06:21 > 0:06:25one of the largest in the world, and it really is packed with weapons.
0:06:25 > 0:06:30At the front, you can see the mouth parts are actually quite complex.
0:06:30 > 0:06:34It has different plates for munching, crushing and mashing.
0:06:34 > 0:06:37And these legs, covered with hairs,
0:06:37 > 0:06:39are perfect for catching prey on the wing.
0:06:39 > 0:06:43The hairs actually serve as extra grip.
0:06:43 > 0:06:46This section here is called the thorax.
0:06:46 > 0:06:47You can see it's very large.
0:06:47 > 0:06:51That's because it houses the wing muscles, which power its flight.
0:06:51 > 0:06:55Those muscles make up two thirds of its bodyweight,
0:06:55 > 0:06:57which is just extraordinary and shows how important
0:06:57 > 0:07:00powered flight is to the dragonfly.
0:07:00 > 0:07:02So let's see all of these in full effect.
0:07:05 > 0:07:09The emperor's flight muscles are warmed up. Time for takeoff.
0:07:09 > 0:07:11And the first thing it needs to do
0:07:11 > 0:07:14is get high up into the air using those large flight muscles
0:07:14 > 0:07:17in order to scour its patch for potential meals.
0:07:17 > 0:07:21Not good news for the damselfly, who's burning up valuable energy
0:07:21 > 0:07:25and tiring out its flight muscles trying to impress the female.
0:07:25 > 0:07:29This distraction means he's unaware the dragonfly is hunting him down
0:07:29 > 0:07:31using its incredible vision.
0:07:32 > 0:07:34Check out those eyes.
0:07:34 > 0:07:38They are some of the most impressive found in the whole natural world.
0:07:38 > 0:07:41They cover pretty much the entire head.
0:07:41 > 0:07:45And each compound eye has about 28,000 lenses.
0:07:45 > 0:07:49It means they can see their prey from as much as 15 metres away.
0:07:49 > 0:07:51Which might not sound like much,
0:07:51 > 0:07:53but if you scale it up to my size,
0:07:53 > 0:07:56it would mean I could spot a pizza from 350 metres away.
0:07:56 > 0:07:58Which I like the sound of!
0:08:01 > 0:08:04But unlike a pizza, the damselfly is no easy meal.
0:08:04 > 0:08:06With its four wings,
0:08:06 > 0:08:10it can weave through the air at incredible speeds.
0:08:10 > 0:08:13But the dragonfly has the manoeuvrability of a helicopter
0:08:13 > 0:08:14and speed of a jetfighter.
0:08:14 > 0:08:19He can fly forwards, backwards, even hover on the spot.
0:08:19 > 0:08:21Let me show you how he does it.
0:08:23 > 0:08:25OK, let's get a closer look at those wings.
0:08:25 > 0:08:28So, at the base of each one is a flexible pivot,
0:08:28 > 0:08:30which means each wing can be moved independently.
0:08:30 > 0:08:35Secondly, they can drive those wings in a figure-of-eight shape,
0:08:35 > 0:08:38which allows them to hover in one spot.
0:08:38 > 0:08:40And thirdly, at the end of each wing
0:08:40 > 0:08:43is a weight called a pterostigma.
0:08:43 > 0:08:46This counterbalances the wings and drives them with more momentum,
0:08:46 > 0:08:49allowing them to fly at a faster cruising speed.
0:08:49 > 0:08:51So they're very well equipped
0:08:51 > 0:08:54to deal with their smaller damselfly cousin.
0:08:54 > 0:08:57But damselflies are put together in a fairly similar way.
0:08:57 > 0:08:59Let's find out how.
0:09:01 > 0:09:04Dragonflies and damselflies are very closely related
0:09:04 > 0:09:08and have a similar bodyplan, but there are subtle differences.
0:09:08 > 0:09:10If you look at the head of the damselfly,
0:09:10 > 0:09:14you can see it's proportionally smaller than that of the dragonfly.
0:09:14 > 0:09:16And more of the eyes are exposed.
0:09:16 > 0:09:19This gives it a broader field of vision,
0:09:19 > 0:09:22so it's equally good at zoning in on its prey,
0:09:22 > 0:09:25but it's also very, very good at looking behind it
0:09:25 > 0:09:27at things that might be attacking.
0:09:27 > 0:09:29Things like its relative, the dragonfly.
0:09:32 > 0:09:35The damselfly, distracted by his courtship dance,
0:09:35 > 0:09:37has only just spotted the dragonfly,
0:09:37 > 0:09:41so starts his bid for freedom immediately.
0:09:41 > 0:09:43The dragonfly spots the flickering wings
0:09:43 > 0:09:46and switches into full-hunt mode, diving down to hit top speed.
0:09:46 > 0:09:50But the damselfly twists out of the dragonfly's path.
0:09:50 > 0:09:53The emperor quickly turns back on track.
0:09:53 > 0:09:55Exhausted from all the showing off,
0:09:55 > 0:09:58the damselfly is beginning to tire.
0:09:58 > 0:10:01The dragonfly's gaining and...
0:10:03 > 0:10:05..grabs a hold with those hairy legs!
0:10:06 > 0:10:10The dragonfly takes a perch and gets stuck in
0:10:10 > 0:10:12with its mighty mouth parts.
0:10:12 > 0:10:15They can slice horizontally and vertically
0:10:15 > 0:10:18and it gets stuck into the flight muscles first
0:10:18 > 0:10:21because it knows these are the most nutritious.
0:10:21 > 0:10:24In the warmer months, dragonflies are a common sight around us
0:10:24 > 0:10:27and it's easy to underestimate these animals.
0:10:27 > 0:10:28That's a mistake.
0:10:28 > 0:10:32Dragonflies are one of the most complete aerial assassins.
0:10:32 > 0:10:35The damselfly displays its acrobatic flying,
0:10:35 > 0:10:38powerful flight muscles and excellent vision.
0:10:38 > 0:10:41But got distracted by a female.
0:10:41 > 0:10:45The large emperor dragonfly with its massive flight muscles,
0:10:45 > 0:10:50faster acrobatic wings and munching jaws demonstrated the perfect hunt.
0:10:50 > 0:10:55Now onto our next pair of hunters locked in a battle for survival.
0:10:55 > 0:10:59This predator twists and turns through the forest in the night.
0:10:59 > 0:11:01It's the daubenton's bat.
0:11:01 > 0:11:05Up against it is this,
0:11:05 > 0:11:08the yellow underwing moth.
0:11:08 > 0:11:14Which has the edge in the race for life. It's time to go Deadly 360.
0:11:17 > 0:11:20We join the action just before the critical moment
0:11:20 > 0:11:24the bat is speeding through the trees in pursuit of its meal.
0:11:24 > 0:11:27The moth is also trying to evade capture.
0:11:27 > 0:11:31The yellow underwing moth is flapping all his might
0:11:31 > 0:11:33but at a fraction of the size of the moth,
0:11:33 > 0:11:35its fate seems inevitable.
0:11:35 > 0:11:41There is a lot more to a hunt than just the final strike.
0:11:41 > 0:11:44What about the hidden factors that'll influence
0:11:44 > 0:11:46what happens in the next few seconds?
0:11:46 > 0:11:50To find out, we have to wind back to the start and dissect the action.
0:11:52 > 0:11:58We're heading to the UK to a piece of woodland in the countryside.
0:11:58 > 0:12:03The forest near a water source near this river
0:12:03 > 0:12:05are where the daubenton's bat lives
0:12:05 > 0:12:08as there are holes in trees and buildings to roost in.
0:12:08 > 0:12:11The trees and plants provide the food required
0:12:11 > 0:12:15for the bats' favourite meal, moths, which are plentiful.
0:12:16 > 0:12:19Which is just as well as a daubenton's bat
0:12:19 > 0:12:24can eat 60% of its body weight in just one hour.
0:12:25 > 0:12:29What special weapons has the bat got to help it catch a meal?
0:12:29 > 0:12:32First up, sharp claws at the end of its legs
0:12:32 > 0:12:36and a mouth crammed with 38 needle-like teeth
0:12:36 > 0:12:39make short work of any prey.
0:12:39 > 0:12:41And they have a super power.
0:12:41 > 0:12:46They can use sound to see at night but I'll explain that later.
0:12:48 > 0:12:52All of that makes our predator a pretty scary prospect.
0:12:52 > 0:12:55But what does our prey have to counter?
0:12:56 > 0:13:00That stocky body is packed with flight muscles to help it escape.
0:13:00 > 0:13:04They have hearing that is far more sensitive than our own.
0:13:07 > 0:13:11They are dazzling in flight. Able to keep any predator on their toes.
0:13:11 > 0:13:14So, well-equipped for evading capture.
0:13:14 > 0:13:16Right, back to the hunt.
0:13:19 > 0:13:22The bat's busy searching for food,
0:13:22 > 0:13:24but nocturnal bats have poor eyesight,
0:13:24 > 0:13:26so, how can it hunt at night?
0:13:26 > 0:13:30Well, it relies on hearing to locate its prey.
0:13:30 > 0:13:34Using something called echolocation. Here's how it works.
0:13:34 > 0:13:38As the bat's flying, it's emitting a series of ultrasonic clicks.
0:13:38 > 0:13:40These are too high for a human ear to hear,
0:13:40 > 0:13:44but they bounce back off all the objects in front of the bat.
0:13:44 > 0:13:47It could be a tree, it could be potential prey.
0:13:47 > 0:13:49The clicks then travel back to the bat
0:13:49 > 0:13:52and are channelled down into the inner ear.
0:13:52 > 0:13:55The change in vibrations and frequency allows the bat
0:13:55 > 0:13:58to build up a three-dimensional picture of the world around it,
0:13:58 > 0:14:02and also to zone in on potential prey.
0:14:04 > 0:14:07The bat is flying towards the moth,
0:14:07 > 0:14:11avoiding the many trees and other obstacles in its way
0:14:11 > 0:14:12using echolocation.
0:14:14 > 0:14:17It twists and turns, reacting in a split-second
0:14:17 > 0:14:19to the information it receives.
0:14:19 > 0:14:22The hope is that despite the moth's excellent flying skills,
0:14:22 > 0:14:26the bat's reactions will mean the moth gets munched.
0:14:28 > 0:14:33We're lucky enough to have an exquisite horseshoe bat skeleton.
0:14:33 > 0:14:36It's 100 years old and very fragile, so I won't touch it,
0:14:36 > 0:14:40but you don't need to to see what makes it so incredible.
0:14:40 > 0:14:44Bats are the only truly flying mammals.
0:14:44 > 0:14:46So they're distantly related to ourselves.
0:14:46 > 0:14:50We probably shared a common ancestor maybe 18-million years ago.
0:14:50 > 0:14:52When you go beneath the fur and the flesh,
0:14:52 > 0:14:56it's remarkable how similar their skeleton is to our own.
0:14:56 > 0:14:59The bones are in different proportions,
0:14:59 > 0:15:02but we've got feet, legs, a pelvis, a complete ribcage,
0:15:02 > 0:15:04a skull full of viciously-sharp teeth
0:15:04 > 0:15:09for chomping through exoskeletons of insects, and this here.
0:15:09 > 0:15:11This is the most remarkable bit for me - the wings.
0:15:11 > 0:15:15This is essentially an arm and a hand.
0:15:15 > 0:15:18We've got the radius and the ulna, which are the forearm bones,
0:15:18 > 0:15:20a wrist, and these are fingers.
0:15:20 > 0:15:24The wing membrane that goes between those is just a flap of skin.
0:15:24 > 0:15:27But it's so efficient that it's enabled this animal
0:15:27 > 0:15:32to become really the second-best flier in the world after the birds.
0:15:32 > 0:15:34Let's see one in action.
0:15:36 > 0:15:38With the bat speeding towards its meal,
0:15:38 > 0:15:41we reveal another essential adaptation of its ear.
0:15:41 > 0:15:45OK, so it's pretty incredible that these animals can build up
0:15:45 > 0:15:48a picture of their world using ultrasonic echoes,
0:15:48 > 0:15:51but it gets even more mind-blowing. Check this out.
0:15:51 > 0:15:55Right, because those ultrasonic clicks are so intense,
0:15:55 > 0:15:58they could shatter the inner-ear bones.
0:15:58 > 0:16:0310 milliseconds before it calls, it disengages them from the eardrum,
0:16:03 > 0:16:04going temporarily deaf.
0:16:04 > 0:16:08It re-engages them again in order to take in the vital information
0:16:08 > 0:16:11as the ultrasonic clicks come back to it.
0:16:11 > 0:16:13That is just crazy!
0:16:16 > 0:16:20The bat has picked up the moth's location and heads straight for it.
0:16:20 > 0:16:24But the yellow underwing has a counterattack.
0:16:24 > 0:16:28A simple ear on its body tuned to the bat's ultrasonic clicks.
0:16:28 > 0:16:32This gives it a head start as it races for cover.
0:16:32 > 0:16:34Mind you, in a flat race,
0:16:34 > 0:16:37there is no way they're going to outpace the bat.
0:16:37 > 0:16:41What they need to do is outmanoeuvre it.
0:16:41 > 0:16:44If it's a hot day and you fan yourself down with your hand,
0:16:44 > 0:16:48what you're effectively doing is creating a localised wind.
0:16:48 > 0:16:51And that is what happens when a bat flies.
0:16:51 > 0:16:54Its wings create a change in air pressure,
0:16:54 > 0:16:56which the moth can detect.
0:16:56 > 0:16:58Its body is covered in tiny hairs,
0:16:58 > 0:17:01and those minute changes in air pressure and wind direction
0:17:01 > 0:17:03are picked up by the hairs
0:17:03 > 0:17:06and it's enough for the moth to sense where the bat's coming from.
0:17:06 > 0:17:09Now, let's see how this drama plays out.
0:17:13 > 0:17:15The bat has locked onto the moth,
0:17:15 > 0:17:17which is desperately trying to find cover.
0:17:18 > 0:17:23As the bat gets closer, it sends faster, high-pitched clicks,
0:17:23 > 0:17:26focussing on the moth's precise location.
0:17:26 > 0:17:31It's in striking distance and swings those deadly feet forward,
0:17:31 > 0:17:34but...it's missed it!
0:17:34 > 0:17:38Oh! That's got to be worth another watch.
0:17:38 > 0:17:41You can see the bat really thinks it's got its prey.
0:17:41 > 0:17:45It swings the feet forward, ready to catch it and...misses!
0:17:45 > 0:17:47The moth simply drops out of the sky.
0:17:47 > 0:17:49There's various things going on.
0:17:49 > 0:17:51First of all, those tiny hairs
0:17:51 > 0:17:54have picked up the change in air pressure as the bat gets close.
0:17:54 > 0:17:58And also, that ear has heard the change in frequency
0:17:58 > 0:18:00of the bat's ultrasonic cores.
0:18:00 > 0:18:02When that happens, the flight muscles of the moth
0:18:02 > 0:18:07simply go into spasm. They seize up and the moth drops out of the sky.
0:18:07 > 0:18:11It's a fairly extreme reaction, but it's kept the moth alive.
0:18:13 > 0:18:16This time at least, the moth outwitted the bat,
0:18:16 > 0:18:18which is an extraordinary outcome.
0:18:18 > 0:18:22But this is only one of hundreds of hunts that will take place tonight.
0:18:22 > 0:18:25I don't think this bat will go back to its roost hungry.
0:18:27 > 0:18:29The Daubenton's bat is a faster flier,
0:18:29 > 0:18:32with echolocation and clawed feet for catching moths.
0:18:34 > 0:18:37But the yellow underwing moth's tiny hairs,
0:18:37 > 0:18:40hearing and fast-reacting flight muscles saved its life.
0:18:42 > 0:18:46This is our last Deadly duo locked in a battle for life or death.
0:18:46 > 0:18:49This is the common kestrel.
0:18:49 > 0:18:51A small, but perfectly formed bird of prey.
0:18:51 > 0:18:57And up against it is this - the speedy field vole.
0:18:58 > 0:19:01Which has the edge in the race for life?
0:19:01 > 0:19:03This is Deadly 360.
0:19:07 > 0:19:11We join the action just before the critical moment of impact.
0:19:11 > 0:19:15The kestrel is hovering 15 metres above its target.
0:19:16 > 0:19:18The vole is busy feeding on grass
0:19:18 > 0:19:21and its brown fur gives it excellent camouflage.
0:19:21 > 0:19:23But the kestrel has spotted movement
0:19:23 > 0:19:26and is dropping out of the sky towards its target.
0:19:28 > 0:19:31It looks like the vole's days are numbered.
0:19:31 > 0:19:34Well, not for sure.
0:19:34 > 0:19:36As you've probably gathered,
0:19:36 > 0:19:39things don't really work that easily on Deadly 360.
0:19:39 > 0:19:43So, let's rewind the action and see how things really unfold.
0:19:47 > 0:19:50The hunt takes place here, in the United Kingdom.
0:19:50 > 0:19:54And more specifically, here, on the verge of a busy motorway.
0:19:54 > 0:19:57Motorway verges and surrounding farmland
0:19:57 > 0:20:01make the perfect home for the field vole. Food is plentiful,
0:20:01 > 0:20:05but grass is low in energy. The vole has to constantly forage for food,
0:20:05 > 0:20:07despite dangers from above.
0:20:07 > 0:20:09So, we've set the scene.
0:20:09 > 0:20:12But how do these animals operate in this environment?
0:20:12 > 0:20:14What attributes do they have, in particular,
0:20:14 > 0:20:17that might tip the balance in their favour?
0:20:19 > 0:20:23Let's have a look at some of the kestrel's killer weapons.
0:20:23 > 0:20:24The talons.
0:20:24 > 0:20:27They have minute bumps on the undersurface to help grasp prey.
0:20:29 > 0:20:32The beak. Perfect for tearing through the flesh
0:20:32 > 0:20:35of anything unlucky enough to end up as lunch.
0:20:35 > 0:20:37And there's its eyesight.
0:20:37 > 0:20:39But more on that later.
0:20:40 > 0:20:43So, with all that to help it hunt,
0:20:43 > 0:20:46you'd think that our predator would have no trouble making a kill.
0:20:46 > 0:20:50But our prey also has some special means of defence.
0:20:54 > 0:20:59It's sound, rather than sight, that the vole uses as a key defence.
0:20:59 > 0:21:03In this dark, covered world, they need acute hearing to sense danger.
0:21:03 > 0:21:06But the key to voles' survival is knowing which way to run
0:21:06 > 0:21:07through its maze of tunnels.
0:21:07 > 0:21:10And it does that by following its sensitive nose.
0:21:10 > 0:21:12If it senses danger, it can shift at high speed,
0:21:12 > 0:21:15covering over three metres in just a second.
0:21:15 > 0:21:20Scaled up, that's like me running at over 120mph.
0:21:20 > 0:21:21Right, back to the hunt.
0:21:22 > 0:21:25The kestrel is out looking for food.
0:21:25 > 0:21:29Using that fixed glare and extremely keen eyesight,
0:21:29 > 0:21:31any prey should keep well hidden
0:21:31 > 0:21:35because those eyes can spot tiny movements. Here's how they work.
0:21:35 > 0:21:39There are several differences in a bird of prey's eyes.
0:21:39 > 0:21:43We have just one focal point and see clearly what's in front of us.
0:21:43 > 0:21:45Everything else is blurred.
0:21:45 > 0:21:48A bird of prey has two focal points, so can have sharp focus
0:21:48 > 0:21:52on absolutely anything inside their field of vision.
0:21:55 > 0:21:59To scour a sufficient area for a potential meal using its sight,
0:21:59 > 0:22:02the kestrel climbs high above the ground.
0:22:02 > 0:22:05The higher it climbs, the more area it can scan.
0:22:05 > 0:22:08Once it sees telltale movement, it turns into the wind.
0:22:08 > 0:22:11But surely it must be harder to fly into the wind?
0:22:11 > 0:22:14The kestrel's doing this deliberately.
0:22:14 > 0:22:17It's turned into the headwind to generate lift.
0:22:17 > 0:22:21Now it can use the fluttering movements of the wings and the tail
0:22:21 > 0:22:25to make micro adjustments so the head can stay perfectly still.
0:22:25 > 0:22:29In fact, it'll move no more than half a centimetre in any direction
0:22:29 > 0:22:32and stay fixated on the ground.
0:22:35 > 0:22:38So, this is a kestrel in the flesh.
0:22:38 > 0:22:40It's a male and I guess the first thing you notice
0:22:40 > 0:22:43is just how surprisingly small he is.
0:22:43 > 0:22:46He's got the classic falcon shape.
0:22:46 > 0:22:48The long, thin tail,
0:22:48 > 0:22:52these wings are swept back and very pointy-ended.
0:22:52 > 0:22:53Can you just see those out wide?
0:22:53 > 0:22:58That's a little bit like the motion you might see as he's hovering.
0:22:58 > 0:23:02If I can get him to settle down... and focus on my finger...
0:23:02 > 0:23:03Look over here.
0:23:03 > 0:23:06..then shift the body very slightly, you can see
0:23:06 > 0:23:09the head stays in exactly the same place,
0:23:09 > 0:23:11just like it does when he's hovering. Can you see that?
0:23:11 > 0:23:13That's extraordinary.
0:23:13 > 0:23:16Look how lightweight this bird is.
0:23:16 > 0:23:20He's easily held on my little finger.
0:23:20 > 0:23:23This is an animal that has to kill using precision.
0:23:23 > 0:23:27It's not like a golden eagle that can use force, power and weight,
0:23:27 > 0:23:30he has to be unbelievably accurate when he's catching his prey.
0:23:30 > 0:23:35Once he has, he has a very special extra weapon, which is in the beak.
0:23:35 > 0:23:37You can see a little notch there.
0:23:37 > 0:23:40You come back from the hooked point of the beak there
0:23:40 > 0:23:42and you can just see that notch,
0:23:42 > 0:23:44which is actually used to dispatch its prey
0:23:44 > 0:23:48by biting clean through the back of the neck.
0:23:48 > 0:23:51And it can kill them almost instantaneously.
0:23:51 > 0:23:55He is a swift assassin. Let's see all of that in action.
0:23:59 > 0:24:02The kestrel's hovering, searching for the vole,
0:24:02 > 0:24:06which is busy feeding on low-energy grass above ground.
0:24:06 > 0:24:09So, surely, it's in danger.
0:24:09 > 0:24:12Fortunately, most of its runways are covered by vegetation,
0:24:12 > 0:24:14keeping it safe from beady eyes above.
0:24:16 > 0:24:18But it's just broken cover.
0:24:18 > 0:24:20The kestrel has spotted movement.
0:24:20 > 0:24:22Launching an attack from this height
0:24:22 > 0:24:25would give the vole too long to escape.
0:24:25 > 0:24:29So, it drops down to about 15 metres to fine-tune the attack.
0:24:29 > 0:24:33The perfect balance between field of vision and time to reach the vole.
0:24:33 > 0:24:36But the vole never hangs around in open space for long,
0:24:36 > 0:24:39and disappears into its maze of pathways.
0:24:39 > 0:24:41While the kestrel resets,
0:24:41 > 0:24:45let's take a closer look at how the vole knows which paths to follow.
0:24:47 > 0:24:50As they move, they leave scent trails of urine.
0:24:50 > 0:24:53These serve as a warning to other voles to stay away.
0:24:53 > 0:24:56But they also function to provide that vole
0:24:56 > 0:24:57with its own scented signpost
0:24:57 > 0:25:01of a direction of how it can move around inside its own territory.
0:25:01 > 0:25:03So in the presence of a predator,
0:25:03 > 0:25:06it knows exactly which escape route to take.
0:25:06 > 0:25:09With this as a defence, how will our kestrel manage to locate the vole?
0:25:14 > 0:25:17The kestrel knows there's food in this general area,
0:25:17 > 0:25:20but the vole has moved undercover and it's too hard to pinpoint.
0:25:20 > 0:25:25But the kestrel has one final weapon to help hunt down its prey.
0:25:25 > 0:25:31The smelly trails that the vole leaves behind could be its undoing.
0:25:31 > 0:25:32There are chemicals inside its wee
0:25:32 > 0:25:35which will glow under ultraviolet light.
0:25:35 > 0:25:38Humans can't see into the ultraviolet spectrum,
0:25:38 > 0:25:41but if we could, there would be a faint glow
0:25:41 > 0:25:44which would look a little bit like this.
0:25:44 > 0:25:47Not so invisible now, is it? And guess what?
0:25:47 > 0:25:51The kestrel can see into ultraviolet light.
0:25:51 > 0:25:54When it's seen from overhead, it must look like this.
0:25:54 > 0:25:58All of the tracks and trails made by the vole are clearly visible.
0:25:58 > 0:26:02And the kestrel can zone in on them and go straight to its prey.
0:26:03 > 0:26:05It swoops down to take a closer look.
0:26:07 > 0:26:09Far from the safety of its burrow,
0:26:09 > 0:26:11the vole's defence strategy is to sit still,
0:26:11 > 0:26:14hoping the kestrel will move on.
0:26:14 > 0:26:17But nothing escapes the kestrel's ever-vigilant gaze.
0:26:17 > 0:26:20Sensing the impending danger,
0:26:20 > 0:26:23the vole now uses a burst of speed to try and outrun the kestrel.
0:26:25 > 0:26:29But its reactions are too late. Let's see that again in slow-motion.
0:26:29 > 0:26:31We can see the kestrel's wings fold in,
0:26:31 > 0:26:36allowing the bird to drop down on a perfect trajectory towards its prey.
0:26:36 > 0:26:41At the last second, the talons open up and punch into that vole.
0:26:41 > 0:26:44Once they're in, they are definitely not coming out.
0:26:44 > 0:26:48Now he finishes it off with his beak and starts feeding.
0:26:48 > 0:26:51The kestrel's hovering method of hunting
0:26:51 > 0:26:53might seem like an awful lot of effort to go to,
0:26:53 > 0:26:56but scientists reckon it's 10-15 times more effective
0:26:56 > 0:26:58than if it was to launch its attack
0:26:58 > 0:27:02from an elevated position, like a branch or a telegraph pole.
0:27:02 > 0:27:05Using this method, it's successful in one out of three hunts,
0:27:05 > 0:27:07which are pretty good odds.
0:27:08 > 0:27:11The vole has superb hearing,
0:27:11 > 0:27:14a sensitive nose to follow smelly tracks and it's pretty speedy.
0:27:16 > 0:27:20But it was outdone by the kestrel's deadly talons, hovering skills
0:27:20 > 0:27:24and eyesight that meant it could zone in to land a winning blow.
0:27:27 > 0:27:28Usually on Deadly 360,
0:27:28 > 0:27:31we concentrate on one family of animals.
0:27:31 > 0:27:34But this time, we looked at a bat, a bird and an insect.
0:27:34 > 0:27:37They could not have been more different.
0:27:37 > 0:27:40Bt what they have in common is that they all use
0:27:40 > 0:27:42the power of flight to Deadly advantage.
0:27:43 > 0:27:45That's all we've got time for.
0:27:45 > 0:27:48Join us next time as three more pairs of animals go head-to-head
0:27:48 > 0:27:51and we analyse the action Deadly 360 style.
0:27:52 > 0:27:54Subtitles by Red Bee Media Ltd
0:27:54 > 0:27:56E-mail subtitling@bbc.co.uk