All language subtitles for Eagle Power NOVA 1080p

♪

♪

NARRATOR:
High-flying...

sharp-eyed...

and deadly.

From mountaintops

to river valleys,

eagles rule the skies.

Strong enough
to take down enormous quarry,

they are
the ultimate bird of prey.

(eagles cawing)

By following a family
of bald eagles...

This is our national symbol.

These are powerful birds.

NARRATOR:
Witnessing eagles in action...

JIM USHERWOOD:
She's doing

eight, nine, ten miles an hour--
up!

And that's fast.

NARRATOR:
And by joining one man
and his feathered friend,

these icons of the air
will be put to the test...

(man cheering)

What a girl!

That is actually
very, very impressive.

NARRATOR:
To reveal what it takes

and even what it feels like...

LLOYD BUCK:
Wow.

We're flying
with a golden eagle.

NARRATOR:...to be the most powerful bird
in the sky.

"Eagle Power."

Right now, on "NOVA."

♪

Major funding for "NOVA"
is provided by the following:

NARRATOR:
It's late winter in Iowa.

(birds chirping)

Under the most recent snowfall,

this bald eagle
is trying to protect

her most precious possessions.

These two eggs must be keptat around 99 degrees Fahrenheit

At night, temperatures plummet
to minus 13.

By day, it's cold enough
to freeze her eyelashes.

But she'll do whatever she can
to keep her eggs safe.

This nest has been rigged
with cameras

to reveal what it takes
for these eggs

to develop
into top aerial predators.
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to develop
into top aerial predators.

♪

Bald eagles are just one of
around 70 different species

in the eagle world,

every one a mesmerizing blend
of power and beauty.

They've conquered a huge range
of habitats across the planet,

from harpy eagles in the
rain forests of South America

to Steller's sea eagles
in the icy North Pacific

and fish eagles
in the great lakes of Africa.

(eagle caws)

They live
at the top of the food chain.

But to dominate their world,

they must overcome
three major challenges.

(eagles cawing, chirping)

They have to cover
hundreds of miles on the wing,

spot their prey
at vast distances,

and tackle the largest quarry

of any bird species.

To reveal exactly how eagles
achieve this...

We need access
to a remarkable bird.

♪

This is Tilly,
a golden eagle

with a wingspan
of almost six-and-a-half feet.

Similar in size to a bald eagle,

golden eagles range acrossmuch of the Northern Hemisphere,

including Asia, Europe,
and North America.

But what makes her special
is the relationship she has

with her lifelong partner,

Lloyd Buck.

♪

Hello!

Hello, my love.

You enjoying yourself, eh?

You're the best, ain't you?

You're a once-in-a-lifetime
bird, you are, eh?

I'll never have another birdlike you ever, will I?

NARRATOR:
Since he was a child,

Lloyd Buck has been obsessed
with birds.

At his home
in North Somerset, England,

he has special licenses
to keep and train

many different species.

But one particular bird stands
out-- Tilly.

They have been together
for 20 years

and have forged
an exceptionally close bond.

Tilly behaves as if Lloyd
is her mate for life.
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Tilly behaves as if Lloyd
is her mate for life.

Go on, go and enjoy yourself,
my love.

I wish I was you.

I wish I was you!

NARRATOR:Thanks to Lloyd's dedicated work
with Tilly,

she acts just like a wild eagle,
but is also comfortable

around scientific equipment
and cameras.

Their unique bond provides
a special opportunity

to learn more about
these remarkable predators.

Eagles are such
inspirational birds.

There's so much, I think,

that we don't understandabout them,

and that's what I'm hoping
to learn here,

a little window into her world,

into the world of eagles.

NARRATOR:
Together, Lloyd and Tilly

will take on a series of tests
that will unlock

the science of eagle power.

(birds chirping)

In Iowa,
it's the first week of April,

and the female seems restless.

One of the chicks
is starting to hatch.

♪

After 37 days of incubation,

it uses a tiny egg tooth on top
of its beak

to crack the shell
in a bid for freedom.

♪

(baby eagle chirping)

♪

(chirping)

♪

Three days later,
it's joined by its sibling.

(baby eagles chirping)

Even at this young age,
they need to eat

almost half their body weight
in meat

every day.

Thankfully,

help is on hand
to bring in fresh supplies.

(bird chirping)

This is the male,

and as with all bald eagles,

he's about 20% smaller
than his mate.

It's thought she might be bigger

to help produce
and incubate the eggs.

Bald eagles normally pair
for life,

but the female's
previous partner

has disappeared,

so this male is new.

The breeding season can last
around ten months,

so rearing the chicks
will be a real test

of their new relationship.
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The chicks' weight can increase
by a staggering 500%

in their first week.

So the adults spend
much of the time hunting.

♪

Bald eagles are masters
of hunting fish.

They can make
up to 90% of their diet.

They are able to pluck their
prey from the water surface

with incredible precision.

(chirping)

But rabbits and squirrels
are also brought to the nest.

For now,

the partnership
of the mother and her mate

is providing
all the food the chicks need.

Eagles around the world
catch a huge variety of prey,

so they have a range
of hunting techniques.

In the mountains of Oman,
this Verreaux's eagle

is after a terrestrial target.

(hyrax sniffing)

Rock hyrax.

These small mammals are equipped
with special vision:

a shield on their iris

that cuts out glare,

helping them spot the predator,
even in bright sunlight.

But this eagle is just a decoy.

Verreaux's eagles
hunt in pairs.

(hyrax squeaking)

One flies in plain sight,

distracting the hyrax.

While the second eagle
hugs the contours of the land,

staying hidden...

Until the last moment.

Catching quarry like this

is a dangerous task.

There is no room for error.

♪

When eagles hunt airborne prey,
if something goes wrong,

they have more space and time
to get out of trouble.

They can even escape a glancing
blow with the water surface.

But when the prey is on hardground, it's a different story.
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But when the prey is on hardground, it's a different story.

One wrong move could result
in a deadly collision.

Especially
with large, heavy prey.

There is no margin for error.

They must capture their victim
without mistake.

So exactly how do eagles
catch prey on land?

To find out,
Lloyd has come to Scotland

to put his golden eagle, Tilly,
to the test.

♪

But first, he needs something
for her to hunt.

This is robo-bunny.

Designed and created
by tech wizard Chris Watts,

with a fake fur coat
and high-speed motors,

it can blend
into the undergrowth

or flash across the open.

It's fitted
with an onboard 360 camera

to help capture
all of the action,

and a bit of bait
to get Tilly's attention.

Okay, she's gonna rouse.

Get ready.

Okay, go, go, go, go,
fast, fast!

(robo-bunny revving)

NARRATOR:
In a matter of seconds,
Tilly locks on to her target.

BUCK:
Ooh!

She's got him, she's done it--
thank you very much, Tilly.

Good girl.

NARRATOR:
To challenge Tilly's
hunting ability,

they repeat the test
in different conditions.

Go!

NARRATOR:
From strong winds
and overcast skies

to bright sunlight.

But the outcome is the same.

Tilly wins.

To reveal
the secret to her success,

the team needs
to go through the footage

frame by frame.

First, Tilly keeps a constant
lock on robo-bunny's position.

Next, she uses her wings
to adjust her trajectory

as the wind changes
or the target moves.

She keeps her legs tucked in
to stay aerodynamic.

Then, just a quarter of a second
before impact,

she swings her feet forwards

so both eyes can see robo-bunny
and her talons.

And she makes perfect contact.
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But there is one more element...

Okay, get ready, Chris.

NARRATOR:
...to Tilly's hunting ability.

♪

Robo-bunny weighs
about 13 pounds,

one-and-a-half times more
than Tilly.

Remarkably, not only
can she strike robo-bunny...

She can lift it into the air.

She even has the strength
to pick it up with one foot--

an amazing achievement
for a load

weighing 150%
of her own body weight.

BUCK (whooping):
Yes!

What a girl!

Good bird,there's a good eagle.

NARRATOR:Tilly's abilities have exceeded

She's able to do this thanks to
the most important weapon

for any eagle--

talons.

As veterinarian
Michael Jones explains.

Eagle talons are very
well adapted for killing prey.

Not only do you have
the strength in their feet,

but you also have
this talon size, as well.

NARRATOR:
The harpy eagle
has some of the largest talons

in the world,

measuring nearly five inches.

JONES:
The talons are largest
on digit one and digit two,

and those are the ones
that typically hold the prey.

Unfortunately for the prey,
because they are so powerful,

the prey is usually going
to succumb

to either extreme pressure,

multiple puncture wounds
to the body and vital organs,

or blood loss.

NARRATOR:To do this, eagles have to grip
with enormous force.

But what is most impressive is,

they can hold
this crushing pressure

for a long time
with little effort,

and it's all thanks
to some impressive mechanics.

Their feet have an in-built
ratchet system.

The tendons in their toes
are ridged,

and so is the tissue
around them.

This creates
a simple locking mechanism,

so the surrounding muscles
can relax

without losing any grip force.

Many bird species
have this adaptation,

but in eagles,

the ridges
are particularly large

to cope with the enormous power.

Creating and maintaining
such a high force

is a critical part
of an eagle's armory.
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And it helps them hunt
even the largest prey.

But these super-strong weapons

have a second, essential,
purpose:

to fight.

Winter in the Alps
is desperately bleak.

Golden eagles soar above the
snowy peaks in search of prey,

but food is so scarce here,

they frequently turn
to scavenging.

(caws)

(crows cawing)

A dead fox.

It could support
this female eagle for days.

Such a prized meal is in demand,

and a devious mob of crows
will try anything

to steal a mouthful.

(eagle chirps, wings fluttering)

A flash of talons seems enough
to remind them

who's at the top
of the food chain.

♪

(crows cawing)

But these annoying crows
are the least of her worries.

The biggest threat
comes from her own kind.

♪

(chittering)

♪

A meal like this attracts eagles
from miles around,

and, if needed,
they'll fight for the food.

In battle, talons
are their weapons of choice.

They use their long legs
to keep their head,

and, importantly, their eyes,

away from danger.

♪

They must fight to survive.

(eagle chirping)

In Iowa...

Our bald eagle youngsters are
now one-and-a-half weeks old,

and still defenseless.
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and still defenseless.

Even the slightest thing
can pose a threat.

♪

Somehow, one has become tangled
in the female's feathers,

and it's at risk of choking.

(baby eagle chirping
desperately)

It's hard to know
how this has happened.

Even the mother seems
confused and stressed.

(baby eagle chirping)

♪

The more she moves around,

the more she pulls
on the chick's neck.

(baby eagle chirping)

It's a lucky escape.

But now it's stuck on its back.

Dad's busy looking
after the other chick,

and doesn't seem
to want to help.

Less than half
of all bald eagle chicks

will survive their first year.

The odds may be against it,

but those powerful talons
come to the rescue.

♪

Over the next few weeks,

the parents will bring in
around five fish a day

to help the chicks grow.

And by a month old,

some obvious changes
start to show.

Their fluffy thermal down,

which has kept them warm
all this time,

is slowly being covered
by juvenile flight feathers.

These will continue to grow

until they reach
their maximum length,

around the time they fledge.

But perhaps the most important
change is in their vision.

Their eyes open
within hours of hatching,

but much like a human baby,

it's thought
they're born with poor sight.

It takes a few weeks
for their eyesight to sharpen

and becomeone of the most powerful senses

JONES:
Eagles' vision is phenomenal.

They have different areas
in their retina

that allow them to have
increased visual acuity.

It's very important that they
have that visual acuity

to be able to capture their prey
and be successful in the hunt.

NARRATOR:
We describe anyone
with exceptional sight
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NARRATOR:
We describe anyone
with exceptional sight

as "eagle-eyed."

♪

But just how good is it?

To find out,

Lloyd Buck has brought
his golden eagle, Tilly,

to a remote part of Scotland.

♪

They're joined
by Professor Graham Martin,

an expert in avian vision.

I'm intrigued
to learn more

about just how good
her eyesight is.

Okay, well, I thinkwe can set something up.

A sort of game of hide and seek,
perhaps?

NARRATOR:
Tilly must find Lloyd
somewhere in this landscape.

Her cage has been covered,
so she can't cheat.

Lloyd has found a position
one-and-a-half miles away

on the other side of the glen,

and weather conditions
are not ideal.

Even with a powerful
telephoto lens,

it's hard to pick out
Graham and Tilly.

BUCK:It's a long way.

I cannot see you withouta pair of binoculars,

and even with the binoculars,

there's that muchmoisture in the air, so...

Let's see what she does now--
this is the big test.

Okay, then, well, I'll,
I'll release her now, okay?

Okay, good luck--
come on, Tilly.

Come on, Tills.

MARTIN (on radio):
She's off.

She's looking very hard.

I'm sure
she's trying to find you.

NARRATOR:
Tilly has never faced
a challenge like this,

but she appears to spot Lloyd
almost immediately

and makes her way
to the other side of the glen.

BUCK:
Come on, Tilly, come on!

(laughs)

NARRATOR:
Tilly takes an indirect route,

riding a series
of strong air currents

to reach Lloyd
more efficiently

and much faster.

BUCK:
She's coming in,she's coming in fast, whoo-hoo!

Absolutely hammering
across the valley.

(cheers)

What a bird she is.

♪

You clever bird.

Whoo-hoo!

What an eagle you are, eh?

Hello!

(laughs)

BUCK (on radio):
Graham, she's on my arm.

That is absolutely incredible--
I'm so pleased with her.

I've never asked her to find me
like that.

That is actually very, very
impressive

because it took really very
little time at all.

NARRATOR:
Tilly spotted Lloyd
in this enormous landscape

from a mile and a half away,

a feat so impressive,
it seems almost superpowered.
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a feat so impressive,
it seems almost superpowered.

So how does she achieve this?

Much like a human's eye,
images are projected

onto the retinaat the back of the eagle's eye.

This area is covered with lightsensitive cells known as cones.

The more cones,
the sharper the eyesight.

A human eye may have 200,000
cones per square millimeter.

But eagles can have
over twice as many,

giving them
the sharpest eyesight

of any vertebrate animal.

The eagles'
supreme visual acuity

gives them a huge advantage.

It means they can quickly pick
out prey in a vast landscape.

But there's
an unexpected downside

to having such sharp vision.

The problem is you don't want
to get the sun in your eyes.

It would destroy all the
very high acuity it's got.

So they have these big eyebrows,

it's like
wearing a baseball cap.

Yeah.That's all designed

to keep the sunout of their eyes

NARRATOR:
This brow ridge
is what gives eagles

their fearsome stare.

But it has a serious drawback.

Of course, if you've got...keeping the sun

out of your eyes, you can'tactually see what's up there.

What an eagle wantsto do is patrol

and look downat the big terrain below it,

and it's bendingits head forward,

it's tipping its head downto have a look.

And that means thatthis blind area

which is designed to keepthe sun out of their eyes

is stopping them actuallylooking where they're going.

NARRATOR:
This blind spot
is not normally a problem.

In their natural environment,they soar high above the trees.

But in a modern landscape,
it can be a fatal flaw.

Across the world,

eagles are colliding
with man-made structures.

Wind turbines,
which are often built

in wild landscapes,
are a particular problem.

So, at this wind farm
in Wyoming,

environmental scientists
like Misti Sporer

are trying
to protect the eagles.

SPORER:
This is the eagle
observation tower.

So when they see an eagle
enter into the area

where the turbine blade
would pass through,

they will shut that turbine down

and the eagle is able to passthrough the area going unharmed.

And then once
that eagle has left,

they start the turbine back up,

so we can continue
generating electricity.

So, we do lose a little bit of
energy throughout the process

but it's worth it
to save an eagle.

NARRATOR:
But human eyesight
isn't always reliable.

When an eagle flies
against the sunlight,

it can be hard to spot.

So this wind farm is now using
artificial intelligence
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So this wind farm is now using
artificial intelligence

to improve their odds.

Identi-Flight utilizes eight
cameras around the bottom,

so it can see in 360 degrees.

There are two cameras up top

that are capable
of tracking an object

as it flies through an area.

NARRATOR:
In just one second,
the system can figure out

if a flying object is an eagle
or not,

and only if it flies too close

will it temporarily shut down
any turbines in its path.

It's over five times
more effective

at seeing birds than humans,

meaning the eagles here
are now much safer.

But across the world,
the biggest threats

to eagles are still humans.

(wind blowing, birds chirping)

In areas around the tropics,

deforestation is threatening
jungle species

like the Philippine eagle...

And the harpy eagle.

There are fewer trees
for them to nest in...

And far less prey
for them to hunt.

Many eagles are also dying
from lead poisoning,

as hunting ammunitioncontaminates leftover carcasses.

In total, more than a third
of all eagle species

are considered to be endangered
or vulnerable.

In the past, conservationists
have been forced

to take drastic action
to save eagles

on the brink of extinction.

During the 1940s,
DDT, a potent insecticide,

was sprayed widely
across the U.S.

to treat pest problems,
large or small.

It was even sprayed on humans
to rid them of parasites.

But DDT seeped
into the ecosystems

and passed from
prey to predator,

so those at the top,

especially eagles,
were hit hard.

It caused
a thinning in eagle eggs,

so they often cracked
during incubation,

and it almost wiped them out
from parts of the U.S.A.

♪

In 1972,
DDT was banned in the U.S.,

and some extreme conservation
measures were launched.

Eggs were taken from the wild,

hatched safely in captivity,

and the chicks were
returned to the nest
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and the chicks were
returned to the nest

to be reared naturally.

And it worked.

♪

There are now thought to be over140,000 bald eagles in the U.S.

It's a truly remarkable
comeback.

In Iowa,

the eaglets havetheir own dangers to deal with.

and have undergone some
remarkable changes.

They're nearly fully grown,

and their feathers
are almost entirely black.

But something seems to be
bothering them.

A wet spring has created
ideal conditions

for an infestation of
blood-sucking black flies,

and they're
attacking the eaglets.

JONES:
Black flies, which are also
called buffalo gnats,

pose a problem for young chicks,

not necessarily because
of a single bite

but because they often attack
the chicks in large swarms

and you get
multiple bite wounds.

And typically chicks
will succumb

to either blood loss
or even anaphylactic shock

related to the bite.

(black flies buzzing)

NARRATOR:
As weather patterns change
year after year,

the number of black flies
seems to be

getting higher in this region,

and this season
is especially bad.

It's almost certainly making
the chicks weaker,

but worse still,
the constant biting

is making them restless.

(black flies buzzing)

One youngster becomes
so uncomfortable,

it climbs the tree to get away.

70 feet up,
this is a risky move.

It's too young to fledge,

and too weak
to deal with the strong wind.

In desperation, it leaps...

and falls to the ground.

The team monitoring the nest
raise the alarm

and send out a search party.

But, in the meantime,
the youngest chick

is also driven from the nest
by the flies.

(eagle cawing)

♪

It still doesn't have full
control of those big talons,
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It still doesn't have full
control of those big talons,

and one mistake is all it takes.

It's a catastrophe.

Somehow, the search team
find it alive,

covered in black fly bites.

But, unfortunately,

the eldest chick is still
nowhere to be seen.

If the chicks were older,

they could have flown to safety.

But they didn't have time
to develop

the strength and coordination
required

for one of the eagle's most
essential skills--

flight.

JONES:
If you have the opportunity,

just watch an eagle fly,
you can certainly appreciate

their majesty,
their grandeur, their ability.

Watching an eagle soar
is freeing,

it's gratifying,
it lifts you up.

♪

NARRATOR:
Eagles dominate the sky.

They can dive at around
150 miles per hour.

And perform surprising
aerobatics when they fight

or display to a mate.

And one of their greatest
aerial abilities

is soaring.

Golden eagles can have
a home range

of over 1,000 square miles.

To cover such vast distances,

they use air currents to push
them high into the air

without flapping their wings,
saving them precious energy.

♪

It's something Lloyd Buck
has always

wanted to know more about.

So he's come to California,
where paragliding expert

Michael Vergalla often flies
alongside wild birds of prey.

By learning what it takes
to fly a paraglider,

Lloyd hopes he will understand
more about how eagles soar.

VERGALLA:
Bring the wing up
in three, two, one.

Wing's coming up.

Okay, walk, walk, walk, walk.

Start running-- run, run, run,
run, run, run, run, run, run!

All right, Lloyd.

BUCK:
Okay, here we go.

We're flying.
We're flying Mike.

(laughs)

Wow!

♪
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I've seen Tilly do this
so many times

and now I'm doing it.
(laughs)

NARRATOR:
Just like an eagle,

Mike is trying to gain altitude

by harnessing
two common air currents.

Thermals form
as the sun heats the earth,

which in turn warms the air
above it,

creating a rising column of air.

Updrafts are created when
horizontal winds

are deflected skywards
by a ridge.

Mike searches for tiny clues

to help find these air currents
and climb higher.

VERGALLA:
You're looking for changes,
you're smelling,

you're listening, you're trying
to use all of your senses

to figure outwhat's happening.

This is what Tilly feels,
this is what Tilly does,

this is what eagles do.Uh-huh.

to find a good thermal

is to watch
and follow the local birds.

We've got another birdon this ridge here

that we can try to join.

NARRATOR:
Mike can tell how strong
a thermal is

by seeing how quickly
the birds climb.

And it's not long before they
spot a special species.

VERGALLA:
Look out at the end
of the ridge.

Do you see the birds?

BUCK:
That's a goldie.

That's a golden eagle.Yep.

Let's get it,let's go.

(laughs)
We're flying with
a golden eagle.

Wow!

♪

BUCK:
I've waited my whole life
for this, Mike.

(both chuckling)

♪

This is the thing that I'vedreamt about since I was a boy.

And my whole life I'veexperienced it through my birds.

VERGALLA:
Uh-huh.

BUCK:
But now I've experienced it
for myself for real with you

and this is just...

I can't put that into words,

it's really quite moving
I would say,

it's quite emotional.

It's okay, you can cry.I've cried.

(laughs)
I feel quite--

I feel very emotional actually.

♪

BUCK:
This is something, Mike,
I'm never going to forget

for the rest of my life.

NARRATOR:
For Lloyd, soaring on
the air currents is pure joy.

But for eagles, it's a criticalcomponent of their daily lives.

To be a dominant predator
of the sky,

they must harness the wind
to cover their territory,
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they must harness the wind
to cover their territory,

and they make it look easy.

To find out just how good eagles
are at soaring,

Lloyd wants
to put Tilly to the test.

He's fitting her with a highly
accurate GPS tracker,

to measure how fast
she can gain altitude.

And a 360-degree camera
to see how her wings

are adapted to soaring.

BUCK:
We'll know exactly
what you get up to, eh?

You're a good girl, yes.

(makes bird sound)

Go on, off you go.
Go on.

NARRATOR:
Tilly quickly finds an updraft

and soars high above the glen.

BUCK:
(chuckles)

You make it look so easy, eh?

NARRATOR:
The 360 camera provides
a wonderful opportunity

to see the world
from an eagle's perspective.

♪

Throughout the flight,

the GPS tracker
and accelerometer

on her back have been collecting
vital information.

♪

Good girl, clever eagle!

NARRATOR:
Professor Jim Usherwood,

a locomotion specialist,can help interpret the findings.

USHERWOOD:
Well, it's really exciting,

especially to having
the video next to her,

you can really see what's
happening all the way through.

We can see her climbing,
circling seven times,

and then reaching quite a height
really very quickly.

She's doing-- ooh, three, four,
five meters a second

up.
BUCK:
Wow.

And that's fast.
Yeah.

That's sort of eight, nine,
ten miles an hour up.

Imagine running up
a ladder that fast.

So she's climbing quickly?

Really fast,

while hardly travelling across
the ground at all.

NARRATOR:
Tilly climbs at this rate

without flapping her wings,
saving huge amounts of energy.

Eagles are able to ride the air
currents effectively

thanks to their large wing area,

but the shape of their wing is
different compared

to many soaring specialists.
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:198018, LOCAL:00:00:00.000

to many soaring specialists.

Albatross have narrow wings up
to 11 feet long,

which generate a lot of lift

for relatively small
amounts of drag.

(albatross honking)

This wing shape
is perfect for gliding,

but it's no good to eagles.

Long wings are very goodfor gliding and soaring,

but they're
horrible for flapping

and of course this thing,at some point,

will need to flap.
Yeah.

USHERWOOD:She'll need to flap to take off,

carry the weaponry
to kill something,

and then carry that food
back home,

at which point you don'tactually want super-long wings.

NARRATOR:
Eagles have to dealwith some competing priorities.

To soar well,
they need to be lightweight,

with extremely long wings.

But to hunt large prey,

they need to be powerful
and heavy,

with shorter, broad wings

that aid maneuverability
and takeoff.

♪

Eagles achieve both--

they manage to create lots of
lift with limited wing length.

So how do they do it?

A key secret
is at the end of their wings.

From Tilly's 360 camera,
it's possible to see

that the feathers on her
wingtips are separated.

Each one of these
primary feathers

acts like a tiny aerofoil,

helping air hug
the upper surface of the wing.

It means eagles can
tilt their wings

at very steep angles on takeoff,

generating lots of lift
to support a heavy load.

It's also thought
these slotted wingtips

can reduce elements of drag,

helping them soar
with greater efficiency.

It's a powerful solution
for a wing

that has to perform
so many tasks.

The eagles' dominance of the sky

is partly what has made them
such iconic creatures.

(Native American tribal music
playing)

and why they feature so
prominently

in cultures around the world,
including many

Native American tribes.

WILLIAM VOELKER:
Only the eagle

can fly high enough
and far enough

to actually see the face of God.

We are truly
a people of the eagle,

and it comes out in
our dress

and everything about our
ceremonial presence.

(people ululating)

NARRATOR:
William Voelker
WEBVTT
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NARRATOR:
William Voelker

is a member of the
Comanche tribe in Oklahoma

and has set up
a special eagle sanctuary

to help support
their traditions.

So to take an eagle feather

and to call on the energy
of this messenger bird,

it's our direct link
with the almighty.

So the eagle is essential
in our spiritual way of life.

♪

NARRATOR:
Historically,
eagles and their feathers

have been taken from the wild
to supply these traditions,

often resulting
in the death of the birds.

But times are changing.

VOELKER:
An eagle can no longer

forfeit its life to benefit
culture, anybody's culture.

Those days are gone.

In today's world we have
a cultural responsibility

to doing everything we can
to enhance eagle populations.

NARRATOR:
At his sanctuary,

William has successfully raised
and released

over 400 eagles
and hawks into the wild.

He also cares for many more
in captivity.

And as these birds naturally
molt their feathers,

William passes them on
to Native American tribes

so the wild populations
can be left unharmed.

♪

(birds twittering)

Back in Iowa,
the nest remains empty.

But remarkably,

the eldest eaglet
has also been found alive.

♪

It was discovered washed up
downriver with a broken leg,

five days after
it fell from the nest.

(bird chirping)

Both eaglets were taken

to a raptor rehabilitation
center for treatment.

It's a reminder that although
eagles are an apex predator,

they sometimes need our help.

Over the next several months,

the eldest eagle's leg
gradually heals.

♪

With care and support from
the raptor center's staff,

both eagles grow stronger.

(bird twittering)

They're given space to develop
their powerful flight muscles.

Finally, the youngest eagle is
ready to be released.

♪

At last it has its own freedom
and independence.
WEBVTT
X-TIMESTAMP-MAP=MPEGTS:198018, LOCAL:00:00:00.000

At last it has its own freedom
and independence.

Almost six months later,
its sibling's leg is healed...

and it, too, returns
to the wild.

♪

By following the journey
from egg to eaglet,

we've seen what challenges
an eagle must overcome

to survive its first year.

And a very special eagle,
called Tilly,

has helped reveal the secretsbehind their greatest abilities,

And she's coming in fast,whoo-hoo!

♪

NARRATOR:
...their hunting techniques...

and their remarkable soaring...

...strength...

...agility...

...and skill.

Revered around the world, these
stunning raptors can't help

but inspire with their
magnificent eagle power.

♪

Major funding for "NOVA"
is provided by the following:

♪

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visit ShopPBS
or call 1-800-PLAY-PBS.

Episodes of "NOVA" are available
with Passport.

"NOVA" is also available
on Amazon Prime Video.

♪

♪