Super Powered Owls Natural World


Super Powered Owls

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They can find prey without ever seeing it.

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They can fly as silent as a ghost...

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..and they can even see in the dark.

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Owls have what appear to be genuine super-powers.

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To understand their amazing abilities,

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we're going to get closer than ever before.

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Meet Luna and Lily.

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Through the eyes of these fluffy little barn owl chicks...

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-WOMAN:

-You can fly!

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..and their extraordinary family,

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we'll reveal the magic behind these mysterious birds.

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-You wouldn't want to be a vole now, would you?

-No.

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No, life as a vole would be brief.

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And working with some of the world's leading scientists...

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-There's not a sound. That is really impressive, isn't it?

-Yup.

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..we'll find out what gives owls their super-powered edge.

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Owls live all over the world...

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..from the frozen north...

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..to scorched deserts.

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With their familiar faces, these charismatic birds

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have captured our imagination.

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There are about 240 different species...

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..and they appear to have conquered our planet.

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They live on every continent, except Antarctica.

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So, what are the secrets of their success?

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Owls are birds of prey.

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Like their cousins, the hawks, eagles, and falcons,

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they have sharp talons...

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..a curved beak

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and a taste for small mammals.

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But they also have a unique set of skills that set them apart.

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Their superpowers.

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To find out more,

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we need to go beneath the surface...

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..and start at the very beginning...

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..when all of the potential for this remarkable bird

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is held in one tiny egg.

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After 30 days of incubation,

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the chick inside is ready to make an appearance.

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But it's a tough task. It can take 48 hours for an owlet

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to break out of its protective shell.

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What are you up to in there?

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You coming out yet, little one? Eh?

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Anxiously waiting in the incubation room

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is an unusual father for a bird.

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I saw you move then, I saw the egg move.

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HE LAUGHS

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You moved!

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Lloyd Buck has been fascinated with owls since he was young.

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Now he and his wife Rose have a whole family of birds,

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including a barn owl called Kensa...

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..Johanna the Tawny Owl...

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Good girl.

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..Arnie,

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Bran,

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Moses,

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PJ...

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and Sasha the tawny eagle.

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Lloyd and Rose love and care for their birds

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like their own children.

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Good boys, come on then.

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Whoo!

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They also train them to star in films.

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We've got a little pellet.

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They have a passion for educating others about birds

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and the importance of protecting them in the wild.

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Through the eyes of this special family,

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we're going to learn more about the owl's mysterious world.

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Lloyd and Rose are going to put their own birds to the test...

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..and, this year, they're expecting some new arrivals...

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..two barn owl chicks.

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-Hiya. How's it going, Lloyd?

-Well, it's all right.

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The eggs are being incubated by experts

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at the Hawk Conservancy Trust, a specialist bird conservation centre.

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He's already started to pip. There's a little bit of movement.

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Can you see the movement?

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Look at that!

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Mike Riley and his team make regular checks on their progress.

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-We'll put her back in now.

-Yeah, yeah.

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The first is nearly ready to hatch.

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It's almost two days since the owlet inside

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made her first pip on the shell.

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Come on, little one.

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Now she's exhausted...

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Go on. What you doing?

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Get out.

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..and running out of oxygen.

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One more big push and you're out!

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Ooh, there you are!

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Hello.

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You've done well, little one, eh?

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That must have been a huge effort, wasn't it? To get out of there.

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See, it's easy to take it for granted when you're here.

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But, actually, it's a really wondrous thing to see new life

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to come into the world, there's something really special

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about that. Really special.

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Mind you, saying that, they're not the prettiest of owlets, are they?

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This chick and her younger sibling

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have come from a pair of captive barn owls.

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OWLET SQUEAK

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As they grow, they'll give us a rare and incredible opportunity

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to learn more about these secretive birds.

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We've already thought of a name, which is Luna.

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We always tend to give our birds names

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because they become part of the family.

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With Lloyd's love and care, Luna grows quickly.

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And, just six days later, she meets her younger sister.

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Lloyd and Rose call her Lily.

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Once the owlets are strong enough, it's time to bring them home.

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-Hello!

-Hello!

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SHE LAUGHS

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All right? There you are.

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SHE LAUGHS

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They're so cute.

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Come on, then.

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During these early days and weeks, Lloyd and Rose need to give

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Luna and Lily round the clock attention.

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Go on. Delicious!

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'When they hatch, they're blind, completely helpless'

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they can't even regulate their own body temperature,

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and they need four feeds a day.

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'It's just like babies, really.

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'But you've taken on the responsibility'

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so you just have to get on with it.

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The Owlets have a long way to go before they transform

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into magnificent super-powered owls.

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Now, shall we write down what you did today, eh?

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Nature will play its part,

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but, right now, they're entirely dependent on Lloyd and Rose.

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By the evening, everyone's exhausted.

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But in the wild, this is the time when most owls are waking up.

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OWL HOOTS

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The tawny owl haunts our nights.

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But why choose to live in this dark and difficult time of day?

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OWL CALLS

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With the help of a special heat-seeking camera,

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we can enter this hidden, nocturnal world.

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It's springtime in the Highlands of Scotland.

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At this time of year, male owls are feeling the pressure.

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This one has a family of hungry mouths to feed in a nearby nest box.

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The thermal camera reveals something else.

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Many mammals are active at night.

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So, despite the dark,

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it's an ideal time to go hunting.

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Success.

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The female comes straight over to collect the catch.

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Her owlets are a month old,

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with a growing appetite.

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One mouse won't be enough.

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But luckily there's plenty more where that came from.

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No other bird of prey can hunt in such darkness.

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So, at night,

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owls have the skies to themselves.

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It's one of the keys to their success.

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But how are they able to see in the dark?

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This is where owls deploy the first of their superpowers.

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Owls have characteristically big eyes.

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A tawny owl's eyes take up a staggering 70% of its skull.

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For us, it's only 5%.

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These large eyes enable the owl

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to gather as much of the available light as possible.

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At the back of the eye,

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the retina has a particularly high density of rod cells.

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These cells are extremely sensitive in low light,

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capable of resolving

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an extra layer of detail,

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which is sent to the brain

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via the optic nerve.

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These special adaptations mean a tawny owl can see an image

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two and a half times brighter than the one we see...

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..which helps it target small mammals lurking in dark undergrowth.

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But tawny owls have another incredible skill.

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They're territorial birds,

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and, as they fly around their home range,

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they create a mental map.

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This means they can find their way in the dark,

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avoiding unseen obstacles.

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So, it's the owl's formidable memory,

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combined with their sensitive vision,

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that helps them take advantage of the night-time world.

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At two weeks old,

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Luna and Lily open their eyes...

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..but it's another few days before they can focus on anything.

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-OWLET PEEPS

-Yes!

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Now at three and four weeks old,

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they're starting to take in their surroundings.

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THEY CHUCKLE

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-Oi, oi!

-Oi, oi!

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ROSE LAUGHS

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To encourage their development,

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Lloyd and Rose take the owlets to meet the children at a local school.

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-Hello, everybody. CHILDREN:

-Hello.

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Hello.

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OK?

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Well, this one here is Luna.

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Luna?

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Yes, and that's Lily.

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-I've got a pet rabbit called Lily.

-Have you?

-Have you? Ah!

-Oh!

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Her nice wing feathers are starting to grow now, you can see.

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Yeah. I think they can fly but they can't.

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No. You know why? Because they're still too small.

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It's a unique opportunity for the children

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to learn more about owls...

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That is the egg that Lily hatched from.

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..and it's also clear how far the owlets have come.

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So, when she hatched, only three weeks ago, 20 days ago,

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she fitted in there. Look.

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She was smaller than her own head is now.

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-Whoa, whoa, whoa.

-Isn't that amazing?

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Now, who knows what's really clever about what owls can do?

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-They can see in the dark.

-That's it! Well done.

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Now to be able to see at night, it's not easy,

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but owls have very, very good eyes.

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They're very clever birds.

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Good night vision is probably the owl's best-known superpower.

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There we are. What do you think?

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-She's as soft as cotton wool.

-She is!

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But Luna was developing another one of her senses...

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..even before she hatched.

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-What do you think?

-Shall we check on its progress?

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Let's have a look.

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On occasions, if you call to 'em, if you chip to 'em,

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they actually call back to you. I'll shush to him.

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Shusssh.

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OWLET CHEEPS

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I heard it! Amazing.

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Remarkably, owlets recognise the calls of their parents

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-even from inside the egg...

-Shusssh.

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-CHEEPING It's amazing!

-Did you hear it?

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Tiny little "Chip, chip."

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We'll put him back in, then.

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..which suggests sound must be an important part of their world.

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But just how important is hearing to adult owls in the wild?

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At a disused aerodrome in Essex,

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this barn owl is on the lookout for her next meal.

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Cold weather, and a blanket of snow, have left her short of food,

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so she's been forced to hunt in the day.

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And now she's got competition...

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..a kestrel.

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It's one of the downsides of hunting during the daylight hours.

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And, even worse, the snow means she can't see her prey.

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So how do you find your food

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when it's hiding out of sight?

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Hunger forces the kestrel to take a chance...

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..but his razor sharp eyesight isn't enough in these conditions.

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Luckily for the barn owl, she has another superpower in her armoury.

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Flying blind won't stop her eating.

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Because, although she can't see it, she can hear her prey,

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even under the snow.

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The kestrel simply doesn't have what it takes.

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So how does an owl's extraordinary hearing work?

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OWL HOOTS

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Some owls have ear tufts...

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..but these feathers aren't used for hearing.

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They're more about communicating mood.

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In fact, the owl's whole head is designed for listening.

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Its distinctive round face is shaped like a satellite dish,

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specifically to detect sound.

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A ring of stiff feathers channel the sound towards the true ears,

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which are hidden at the side of the face.

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Some species of owl have one ear opening higher than the other.

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This unique adaptation

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allows the owl to work out what height a sound is coming from,

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as well as the direction.

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Sound arriving at the left ear

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before it reaches the right,

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tells the owl it's coming from below.

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At certain frequencies, an owl's hearing

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is ten times more sensitive than ours.

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This extraordinary skill

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means this great grey owl can locate its prey...

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..even when it's out of sight.

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Come on.

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Shusssh.

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Kensa.

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Hearing is a key part of the owl's hunting strategy...

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Kensa.

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..in any environment.

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Shusssh. Good girl. Come on.

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Lloyd and Rose have an 11-year-old barn owl called Kensa...

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Good girl.

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..who they've trained to hunt to the sound of a beeper box.

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BEEPING

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When she hears that beep,

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Kensa knows exactly where to find her food.

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But what about at night?

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Just how much is she relying on her hearing then?

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So, that can go here.

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To find out,

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Lloyd's made an indoor hunting ground.

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So, we're going to put the beeper in there.

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Over to you, Rose.

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He wants to be certain Kensa's not using her sight.

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I want to make it totally dark.

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So he creates an artificial night.

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-OK, Rose?

-Yep.

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Right, here we go.

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Torch off.

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OK, ready?

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With our infrared cameras,

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we can see what's going on,

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but Lloyd, Rose and, importantly, Kensa

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are in total darkness.

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KENSA HISSES Hold on, where is she?

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She must be by me, by the sounds of it.

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BEEPING

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-Sounds like she's under my feet somewhere.

-Shusssh.

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KENSA CRIES

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I can't hear, has she got it?

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-I don't know.

-Do you think she's got it?

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Oh, my gosh, she's got it!

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THEY LAUGH

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Using only her hearing,

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Kensa locks straight on to the beeper.

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BEEPING

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That sounds good!

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I'll get me torch, hold on. Kensa.

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Shusssh. Good girl, you clever owl.

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Who needs eyes when you've got ears like that, eh?

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But the owl's super-human hearing

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is made even more effective by their party trick.

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They can turn their head through an incredible 270 degrees.

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If we did that,

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we'd cut off the blood supply to our brains and pass out.

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But owls have evolved special adaptations in their necks.

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As their head turns,

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wide spaces in the neck vertebrae

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make sure the blood vessels don't get crushed...

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..and enlarged arteries at the top of the neck create a reservoir,

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which keeps a constant supply of blood to the brain.

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This astonishing flexibility allows the owl

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to focus its super-sensitive vision and hearing...

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directly at its prey.

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In just two months,

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there's been an amazing transformation.

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Luna and Lily have grown from helpless little chicks...

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..to near-adult barn owls.

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Now their fluffy down

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is being pushed out

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by proper flight feathers...

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Ooh! Come on, then.

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-Shusssh.

-SHE CHUCKLES

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..which marks the arrival of the biggest milestone

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in their young lives.

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Luna, come and get weighed.

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Now Luna's started using her wings,

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she's being slightly less cooperative

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about her daily weigh-in.

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Luna, I know you're hungry.

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Come on, then.

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Come on, then.

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Good girl. Now, steady.

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Don't go mad.

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Steady, steady.

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Good girl. That's it.

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Wahey!

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Luna, you can fly!

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Luna's very first flight starts with a leap of faith from the scales...

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..and now she's hop-flying every chance she can get...

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..leaving her younger sister to stare in wonder.

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ROSE LAUGHS

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She's on the tripod!

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Oh, yeah, she might.

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Mastering this new skill doesn't happen over night.

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She might have another go, though.

0:26:330:26:35

But it's something she must get right,

0:26:420:26:44

as flight is perhaps an owl's greatest superpower.

0:26:440:26:48

Luna.

0:26:490:26:51

Don't fall in the bucket of water!

0:26:510:26:53

Ooh, you're seeing what water is.

0:26:550:26:57

Is that interesting?

0:26:570:26:59

Shusssh. Oop!

0:27:010:27:02

THEY LAUGH

0:27:050:27:06

I told you not to go in the bucket of water.

0:27:060:27:10

Oh, poor thing!

0:27:100:27:11

You'll get very wet.

0:27:110:27:13

I don't think you'll do that again in a hurry.

0:27:130:27:15

Luna and Lily are still spending the night in the house.

0:27:170:27:21

Now Luna can fly, nowhere is out of bounds.

0:27:260:27:29

And her enthusiastic flight practice

0:27:360:27:38

is getting her into trouble.

0:27:380:27:40

Whoa! That's on the picture, Luna.

0:27:420:27:44

THEY LAUGH

0:27:440:27:46

That bird!

0:27:460:27:48

But Luna's lucky.

0:27:480:27:49

A house is a relatively safe place to practise this vital skill.

0:27:490:27:53

In the wild, some owls face a monumental challenge.

0:28:000:28:03

Californian redwoods are giants of the forest,

0:28:070:28:11

the tallest trees in the world.

0:28:110:28:12

And perched precariously at the top of this one

0:28:140:28:18

is a family of great grey owls.

0:28:180:28:20

It's a wonderfully safe place for a nest.

0:28:300:28:32

OWLET CRIES

0:28:330:28:34

But when it comes to learning to fly,

0:28:340:28:37

there are some obvious challenges.

0:28:370:28:39

Launching yourself off the equivalent of a 30-storey building

0:28:480:28:52

takes some courage.

0:28:520:28:54

Until they get the hang of it,

0:29:050:29:06

these owlets rely on being able to cling on.

0:29:060:29:09

This is less flying,

0:29:190:29:20

more falling with style.

0:29:200:29:22

He makes it safely to the ground.

0:29:310:29:33

But they must keep practising,

0:29:440:29:46

so now it's a long hard climb

0:29:460:29:49

back to the top.

0:29:490:29:50

And it's not long before they have lift off.

0:29:580:30:02

Although Lily's a week younger than Luna...

0:30:120:30:15

-SHE WHISTLES

-Whoo!

0:30:150:30:17

..like any younger sibling, she's not going to be left behind.

0:30:170:30:20

You're a clever, clever, clever girl.

0:30:200:30:23

I know you're hungry.

0:30:230:30:25

Before long, she's progressed from flapping...

0:30:250:30:28

to flying.

0:30:280:30:30

ROSE LAUGHS

0:30:310:30:33

Ah, that is so clever!

0:30:330:30:36

The power of flight is something that sets birds apart.

0:30:360:30:39

SHE WHISTLES

0:30:390:30:41

Lily!

0:30:410:30:43

Whoo!

0:30:430:30:44

And owls have refined their technique

0:30:440:30:47

with some incredible adaptations.

0:30:470:30:49

Ready?

0:30:530:30:54

-You ready?

-Yep.

0:30:540:30:56

Lily!

0:30:560:30:58

Come on.

0:30:580:30:59

To fully understand this superpower, we need to go back to basics.

0:30:590:31:03

Lily!

0:31:030:31:04

What does it take for Lily to get airborne?

0:31:070:31:10

To find out, Lloyd and Rose have enlisted the help

0:31:120:31:16

of bird expert Professor Graham Martin...

0:31:160:31:19

and high speed cameraman Mark Payne-Gill.

0:31:190:31:22

For a bird to take to the air,

0:31:320:31:34

it has to overcome two forces.

0:31:340:31:37

Gravity,

0:31:390:31:40

the invisible pull that keeps us grounded...

0:31:400:31:43

..and drag,

0:31:440:31:45

which is the resistance we experience

0:31:450:31:47

as we move through the air.

0:31:470:31:49

Birds use their wings to create lift...

0:31:520:31:56

and thrust.

0:31:560:31:57

But how do they do it?

0:32:030:32:04

Birds' wings are the shape of an aerofoil.

0:32:080:32:11

Air travelling over the top of the wing

0:32:130:32:15

has to travel faster than air travelling beneath.

0:32:150:32:18

This creates a difference in air pressure,

0:32:200:32:23

which generates lift.

0:32:230:32:25

To gain forward momentum,

0:32:270:32:29

birds flap their wings.

0:32:290:32:31

This makes the air flowing over them spiral off the trailing edge.

0:32:320:32:35

These vortices

0:32:390:32:41

thrust the bird forwards and upwards.

0:32:410:32:44

These are the basic principles of all flight.

0:32:510:32:54

But what's so unique about the way owls fly?

0:32:560:32:59

-We fly quite a few different types of bird...

-Yeah.

0:33:020:33:05

-..of varying sizes.

-Yeah.

0:33:050:33:07

But the one thing I notice about the owls

0:33:070:33:09

is they always appear to be a lot slower

0:33:090:33:11

when they're flying than the other birds.

0:33:110:33:13

Well, all birds have got different wing shapes

0:33:130:33:15

and they can fly at different speeds -

0:33:150:33:17

it's just like aircraft.

0:33:170:33:19

So if you look at the wing size of a barn owl,

0:33:190:33:21

it's actually got a very big wing,

0:33:210:33:23

and so they can fly very slow, very controlled.

0:33:230:33:26

To really understand the barn owl's slow flight,

0:33:290:33:33

Lloyd's putting Lily to the test against two of his other birds.

0:33:330:33:36

Maisie the greylag goose,

0:33:430:33:45

a long distance endurance flier...

0:33:450:33:47

..and Moses the peregrine falcon -

0:33:500:33:52

one of the fastest birds on earth.

0:33:520:33:54

The peregrine takes the lead.

0:34:070:34:10

Its long and pointed wings are quite flat,

0:34:100:34:13

designed for speed and manoeuvrability,

0:34:130:34:15

which it needs to hunt.

0:34:150:34:17

The goose is next.

0:34:200:34:21

Weighing three kilograms,

0:34:230:34:25

its relatively short and narrow wings work hard to get it airborne,

0:34:250:34:29

but once up, it can sustain this for hours.

0:34:290:34:32

The barn owl has the largest wings in relation to its body

0:34:380:34:42

and its aerofoil is very curved,

0:34:420:34:45

which generates a huge amount of lift.

0:34:450:34:47

So the barn owl can fly slower

0:34:490:34:52

and with fewer wingbeats than most other birds.

0:34:520:34:55

Whoo! Good girl.

0:34:550:34:58

But why is that important?

0:35:000:35:02

Sometimes when you're watching the owls fly,

0:35:020:35:04

they go so slowly

0:35:040:35:05

it looks as if they're not going to be able to maintain flight.

0:35:050:35:08

That's right. They are actually flying so slow

0:35:080:35:11

that they're very, very close to stalling.

0:35:110:35:13

But, of course, that's what they need to do

0:35:130:35:16

because when they're doing that very, very slow flight,

0:35:160:35:18

they're hunting.

0:35:180:35:20

It may be just a little rustle in the grass,

0:35:200:35:23

so they've got to be in a position to drop out the sky

0:35:230:35:25

and investigate it.

0:35:250:35:26

-And get a nice, tasty vole.

-Absolutely, yeah.

0:35:310:35:33

Owls have evolved a wing design

0:35:360:35:38

perfectly suited for their aerial hunting strategy.

0:35:380:35:41

Slow, yet deadly.

0:35:440:35:46

But the refinements don't stop there.

0:35:500:35:52

These birds have fine-tuned their flight

0:35:540:35:56

so each species has subtle adaptations

0:35:560:35:59

for the environment it lives in.

0:35:590:36:00

Like the barn owl,

0:36:050:36:07

these short-eared owls have very large, broad wings,

0:36:070:36:10

ideal for flying slowly whilst hunting over open ground.

0:36:100:36:14

Owls that live in woodland, like tawny owls,

0:36:180:36:21

have shorter, more rounded wings

0:36:210:36:23

to help them manoeuvre between trees.

0:36:230:36:26

Wherever they live,

0:36:310:36:32

all owls have an amazing aerial agility.

0:36:320:36:35

They're even able to take off vertically from standing.

0:36:380:36:40

It's a great defensive move,

0:36:460:36:47

especially when you've got young to protect.

0:36:470:36:50

SHARP BIRDCALL

0:36:500:36:51

SHARP BIRDCALL

0:36:520:36:54

A dive-bombing arctic skua is no match for the snowy owl.

0:37:010:37:06

Such mastery of the skies seems to make these owls fearless...

0:37:190:37:22

..even against one of the Arctic's largest predators.

0:37:250:37:28

OWL SHRIEKS

0:37:340:37:35

OWL SHRIEKS

0:37:480:37:49

Her supreme flying skills drive the wolves away...

0:38:020:38:05

..and her family is safe.

0:38:120:38:14

Owls have one more amazing flying skill...

0:38:240:38:26

..and this one is totally unique.

0:38:310:38:33

Floating across the meadow,

0:38:370:38:39

the barn owl is ghost-like in appearance...

0:38:390:38:42

..and mysteriously quiet, too.

0:38:440:38:46

But just how quiet is a hunting barn owl?

0:38:500:38:52

Kensa.

0:38:560:38:57

Shusssh.

0:38:570:38:58

To find out, Lloyd's taken Kensa to a special studio...

0:38:580:39:02

..where Graham...

0:39:050:39:06

WINGBEATS

0:39:060:39:07

..and sound recordist Gary Moore are going to put her to the test.

0:39:070:39:11

..against Smudge the pigeon...

0:39:150:39:18

..and Moses the peregrine.

0:39:200:39:22

The birds' challenge -

0:39:270:39:29

to fly over a series of super-sensitive microphones.

0:39:290:39:32

ROSE WHISTLES

0:39:320:39:34

WINGBEATS

0:39:340:39:35

Good girl.

0:39:350:39:37

THEY MURMUR

0:39:370:39:38

Moses.

0:39:380:39:40

Mo.

0:39:400:39:41

WINGBEATS

0:39:430:39:45

And now it's Kensa's turn.

0:39:480:39:50

Shusssh.

0:39:520:39:53

Here we go!

0:39:530:39:55

Shusssh. KENSA SHRIEKS

0:39:550:39:57

KENSA SHRIEKS

0:40:010:40:03

-Did you hear anything?

-Wow, that was really good.

0:40:030:40:05

No, nothing at all. Absolutely quiet.

0:40:050:40:08

It was amazing!

0:40:080:40:09

But what have the microphones picked up?

0:40:110:40:13

TUB RATTLES

0:40:130:40:15

The decibel waveforms show the sound being generated

0:40:150:40:18

by the birds in flight.

0:40:180:40:21

WINGBEATS

0:40:210:40:22

Each spike is an individual wingbeat.

0:40:250:40:28

THUD

0:40:310:40:33

WINGBEATS

0:40:350:40:37

THUD

0:40:440:40:45

But with the barn owl...

0:40:520:40:53

..there's almost nothing.

0:40:560:40:57

Even our array of super-sensitive microphones

0:41:000:41:02

fail to pick up any sound of Kensa in flight.

0:41:020:41:05

..and here's the owl doing exactly the same.

0:41:050:41:07

KENSA SHRIEKS

0:41:070:41:10

KENSA SHRIEKS

0:41:140:41:15

Nothing, nothing at all.

0:41:160:41:19

-I'll play it again.

-KENSA SHRIEKS

0:41:190:41:20

KENSA SHRIEKS

0:41:250:41:27

-There's not a sound.

-Yes.

0:41:270:41:28

That is really impressive, isn't it?

0:41:280:41:31

Yes, it shows that they really are silent fliers.

0:41:310:41:33

So how does a barn owl fly so silently?

0:41:350:41:37

WINGBEATS

0:41:440:41:45

When air moves, it generates sound.

0:41:490:41:52

The more movement, the greater the sound.

0:41:580:42:01

The pigeon's large body and small wings

0:42:050:42:07

mean it can't stay airborne without a lot of fast flapping.

0:42:070:42:11

This creates turbulence in the feathers below.

0:42:150:42:18

WINGBEATS

0:42:180:42:20

The peregrine has much larger wings,

0:42:240:42:26

which it uses to build up speed and chase down its prey.

0:42:260:42:29

The barn owl is far more graceful.

0:42:540:42:56

Kensa's large wings and small body

0:43:080:43:11

make it easier for her to generate lift.

0:43:110:43:13

So, just one gentle wingbeat

0:43:180:43:21

sees her gliding effortlessly through the air...

0:43:210:43:23

..creating little more than a whisper in the feathers below.

0:43:260:43:29

But that's not the only thing

0:43:380:43:40

that helps the barn owl achieve near-silent flight.

0:43:400:43:43

Its flight feathers have noise-reducing fringes

0:43:510:43:54

on the leading and trailing edges.

0:43:540:43:56

And they have a velvet-like top to them.

0:44:030:44:05

These soft surfaces absorb air movement,

0:44:080:44:12

reducing any turbulence and minimising sound.

0:44:120:44:16

Birds like pigeons and peregrines

0:44:210:44:23

don't have these specialised features.

0:44:230:44:25

So, why are they important for an owl?

0:44:320:44:34

I suppose being able to fly so silently

0:44:360:44:40

gives you two huge advantages over your prey.

0:44:400:44:42

Not only on a dark night, if you were a vole,

0:44:420:44:45

would you not hear your killer coming - you wouldn't hear it!

0:44:450:44:49

Also, it allows the owl, I suppose, to pinpoint its prey

0:44:490:44:53

without any interference from the noise of their wings.

0:44:530:44:56

It doesn't want to hear itself

0:44:560:44:57

as it's trying to home in on a very, very small sound.

0:44:570:45:00

-That's incredible, isn't it?

-Absolutely.

0:45:000:45:02

Silent flight is possibly the greatest

0:45:040:45:07

of all the owl's superpowers

0:45:070:45:09

and it makes a huge difference to their hunting success.

0:45:090:45:13

But, like every superpowered creature,

0:45:150:45:18

owls have their kryptonite.

0:45:180:45:21

THUNDER RUMBLES

0:45:210:45:22

Rain.

0:45:270:45:28

OWL CALLS

0:45:380:45:39

This male, short-eared owl has a young family back at the nest.

0:45:410:45:45

When it rains, they're all at risk.

0:45:460:45:49

Because there's a price to pay for having silent feathers -

0:45:550:45:58

they can't also be waterproof.

0:45:580:46:01

The female hunkers down.

0:46:080:46:10

She can't move, or her chicks will be at risk of hypothermia.

0:46:120:46:15

The male is struggling, too.

0:46:200:46:22

He can't hear his prey over the driving rain.

0:46:240:46:27

So, today, his family will go hungry.

0:46:320:46:35

Wet weather can be fatal for owls.

0:46:420:46:44

It's one of the reasons some don't make it through their first winter.

0:46:500:46:54

Learning to hunt for themselves

0:47:100:47:12

is a challenge all young owls face

0:47:120:47:14

if they're going to survive.

0:47:140:47:16

Little owls fledge between four and five weeks.

0:47:230:47:26

After this, their parents encourage them to fend for themselves.

0:47:280:47:32

The adults usually hunt voles and other small mammals...

0:47:370:47:40

..but these pint-sized youngsters don't have the experience

0:47:430:47:47

to take on such tricky prey.

0:47:470:47:49

So, they start by practising on something a bit easier.

0:47:580:48:01

Earthworms won't be enough to see them through the winter...

0:48:140:48:17

..but they're great for honing their hunting technique.

0:48:200:48:23

As birds of prey,

0:48:320:48:34

owls are defined by their habit for hunting small animals.

0:48:340:48:37

Mastering the kill is a critical survival skill...

0:48:390:48:42

..but it's clearly not easy.

0:48:470:48:48

So what exactly is it youngsters need to learn?

0:48:490:48:52

To find out, Lloyd's brought Kensa

0:48:540:48:57

to meet animal locomotion scientist Dr Jim Usherwood.

0:48:570:49:00

Together they'll try to deconstruct the moment she pounces on her prey.

0:49:020:49:06

In Jim's laboratory,

0:49:080:49:10

they've created a mini hunting ground.

0:49:100:49:12

That can go there.

0:49:120:49:14

Got the beeper?

0:49:140:49:15

They've hidden a beeper box and some food in the long grass.

0:49:150:49:18

Right...

0:49:180:49:20

And, concealed beneath the turf,

0:49:200:49:22

is a special device that can measure the forces at work.

0:49:220:49:25

BEEPING

0:49:260:49:28

-She's got it.

-There's a good girl.

0:49:350:49:38

You clever old barn owl.

0:49:410:49:43

How much force, then, does she exert on the pounce?

0:49:430:49:48

So, here we have the vertical forces of the owl.

0:49:480:49:51

And, so, there's the force of taking off,

0:49:510:49:53

and then you see some fairly powerful flaps,

0:49:530:49:56

and then she eases off the gas,

0:49:560:49:59

uses gravity to come back down at speed,

0:49:590:50:01

hits the ground at about five metres a second,

0:50:010:50:04

-with a force that's something like 12 times body weight.

-Wow.

0:50:040:50:07

This is the moment an owl must bring all its superpowers together.

0:50:120:50:17

Hanging silently in the air,

0:50:240:50:27

Kensa uses her hearing and eyesight to find her target.

0:50:270:50:30

She angles her face to pinpoint the sound.

0:50:390:50:41

Once she's locked on,

0:50:470:50:49

she positions her entire body for the pounce.

0:50:490:50:53

And then, what I find really interesting,

0:51:050:51:07

look, when she comes down,

0:51:070:51:09

basically she's going headfirst towards the ground.

0:51:090:51:12

And it's only now the legs come forwards.

0:51:120:51:15

But the legs are still very, very bent,

0:51:150:51:17

and, then, it's right at the very end the legs extend

0:51:170:51:20

and then you get that thump.

0:51:200:51:22

So, she's coming down at five metres a second.

0:51:220:51:24

She's hitting the ground at around 12 times her body weight.

0:51:240:51:29

-Mm-hm.

-Which would make sense,

0:51:290:51:30

because primarily she's hunting small mammals.

0:51:300:51:34

So she wants to hit them with as much force as possible,

0:51:340:51:36

to disable it and kill it.

0:51:360:51:38

What I was thinking was those long legs would be useful

0:51:380:51:41

to ease off the force -

0:51:410:51:43

but she's not easing off at all.

0:51:430:51:44

She's actually extending with her legs just as she hits the ground,

0:51:440:51:48

then gives it a good old thump.

0:51:480:51:49

To put this in perspective, the force of Kensa's pounce

0:51:530:51:57

is the equivalent of a 12-tonne truck hitting an 80kg man.

0:51:570:52:01

It's unlikely her prey

0:52:040:52:06

would survive the impact.

0:52:060:52:07

You wouldn't want to be a vole, would you, now?

0:52:080:52:11

No, no. No, life as a vole would be brief.

0:52:110:52:13

LLOYD LAUGHS

0:52:130:52:14

The journey to mastering such finely-tuned superpowers

0:52:280:52:31

starts early.

0:52:310:52:33

It's now three months since Luna and Lily entered the world.

0:52:390:52:43

They started to use their senses even before they hatched.

0:52:500:52:53

Shusssh.

0:52:560:52:57

OWLET CHEEPS

0:52:570:52:59

I heard it! Amazing.

0:52:590:53:02

First, their hearing.

0:53:020:53:04

And then, within three weeks,

0:53:070:53:10

they were using their eyesight to explore their surroundings.

0:53:100:53:13

Their development was encouraged by Lloyd and Rose

0:53:180:53:21

every step of the way.

0:53:210:53:23

Who knows what's really clever about what owls can do?

0:53:230:53:25

-They can see in the dark.

-That's it! Well done.

0:53:250:53:28

At just two months old,

0:53:300:53:31

Luna and Lily started to fly.

0:53:310:53:33

Wow!

0:53:350:53:37

Whoa, that's on the picture, Luna.

0:53:380:53:41

Now, at three months old,

0:53:510:53:53

it's time to see if they can put it all together.

0:53:530:53:56

Shusssh.

0:53:590:54:00

Come on, Luna.

0:54:000:54:02

Luna.

0:54:020:54:03

ROSE LAUGHS

0:54:030:54:04

Hello.

0:54:040:54:05

Mind your feet! Lily, come here.

0:54:050:54:09

Luna!

0:54:090:54:10

Luna and Lily have grown up

0:54:100:54:12

in an extraordinary family...

0:54:120:54:14

Good girl.

0:54:140:54:16

..and become bold and confident birds.

0:54:160:54:19

Lily! Yep.

0:54:190:54:20

ROSE LAUGHS

0:54:220:54:24

Luna, you're not meant to be on the camera.

0:54:240:54:27

Lily!

0:54:270:54:29

-Good girl.

-Good girl, good girl!

0:54:290:54:32

But despite their unusual upbringing,

0:54:320:54:35

out in the meadow, their natural instincts kick in.

0:54:350:54:39

They're hunting, just like adult barn owls,

0:54:430:54:46

using all their superpowers of keen eyesight,

0:54:460:54:50

extraordinary hearing

0:54:500:54:52

and slow and silent flight.

0:54:520:54:54

Shusssh.

0:54:570:54:58

Good girl, come on.

0:54:580:54:59

Nature has played its part...

0:55:010:55:03

BEEPING

0:55:030:55:04

Ooh, good girl. Got it?

0:55:040:55:06

..and Lloyd and Rose have done everything they can

0:55:060:55:09

to get both birds to this moment.

0:55:090:55:10

Got it stuck?

0:55:100:55:11

There you go.

0:55:130:55:15

But, while Lily continues to hone her skills living alongside them...

0:55:150:55:19

..there's been an unexpected twist to her sister's story.

0:55:200:55:23

One evening,

0:55:310:55:32

Luna flew off...

0:55:320:55:34

and she didn't come back.

0:55:340:55:36

For Lloyd, it only underlines her graduation

0:55:400:55:43

from owlet to adult,

0:55:430:55:46

reassuring him that he's equipped her with everything she needs

0:55:460:55:49

for an independent life.

0:55:490:55:51

I've given her all the skills that she needs to survive.

0:55:520:55:55

I've been her parent. She's chosen to go -

0:55:550:55:58

it's her choice -

0:55:580:56:00

and we always say they've got that choice to stay or go.

0:56:000:56:04

It's sad for me because you get really attached to them,

0:56:040:56:08

but they don't have those trappings of human sentiments.

0:56:080:56:11

She's just gone on to the wild to do her own thing.

0:56:110:56:14

Now, more than ever, Luna will rely on those special skills

0:56:220:56:26

that set owls apart.

0:56:260:56:28

For centuries, these enchanting birds have captured our imagination.

0:57:020:57:07

With their haunting calls and ghostly appearances,

0:57:140:57:18

owls add a magic and mystery to our landscapes.

0:57:180:57:22

Their charismatic faces are so familiar,

0:57:350:57:38

perhaps because they look that bit more human

0:57:380:57:40

than other birds.

0:57:400:57:42

But it's their superpowers

0:57:550:57:57

that make them one of the most successful

0:57:570:57:59

and best-loved birds on our planet.

0:57:590:58:01

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