NOVA

From frigid oceans...

Okay, there he is.

...to distant jungles...

You can keep going a little bit more.

...there's a hidden world

of exotic creatures

just out of view.

Finding the animal is like looking

for a needle in a haystack.

It's really difficult.

Around the world,

researchers are tracking the most vulnerable animals,

trying to save them before they vanish forever.

This powerful-looking animal is so fragile.

The pieces of knowledge that are needed

to make it survive

are critical.

Now, new technology

is revealing their secret lives.

They're really silent little spies

that make no noise,

that can capture intimate moments of the animals.

You get millions and millions of photographs,

and you suddenly see things for the first time.

Frame by frame,

the invisible world of animals is coming to life.

I could not believe this species existed,

that it was right here, around us.

I had no idea they did that.

Their habits, fears, and most intimate moments.

It has completely revolutionized

our ability to understand behaviors.

Rare footage from the animal kingdom

is offering up new clues.

Can we uncover the secrets to these animals' survival

before it's too late?

"Animal Espionage,"

right now, on "NOVA."

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

Our planet is teeming with millions of species,

yet we've only been able to study a small fraction of them.

In this hidden world, much goes unseen...

until now.

Advances in camera technology

are opening our eyes to the world around us.

The invaluable information that people will get

from a simple, wee, little camera

that anybody can buy off the shelf,

it's unbelievable.

What can researchers learn by spying on animals?

Why are they doing that?

And why did they do that?

And what are they going to do next?

Can a new wave of animal surveillance

turn the tide

and help preserve our planet's most vulnerable species

before they disappear?

Cumberland Sound, Canada,

about 300 miles west of Greenland.

Beneath these frigid waters dwells a mysterious giant...

the bowhead whale.

Little footage of these 100-ton creatures exists.

They are the longest-living mammal on the planet.

Some have reached the ripe old age of 200.

But their survival isn't guaranteed.

The species could be in trouble.

They're living in the Arctic, and this is a place

where climate change could be threatening their, their future.

Marine biologist Sarah Fortune studies bowheads

in Cumberland Sound,

where the whales come to feed for months at a time.

But rising temperatures and melting sea ice

are affecting their primary food source...

tiny animals called zooplankton.

Bowheads favor a nutrient-rich variety,

and their numbers are dropping.

This could be catastrophic for the whales:

one bowhead needs to eat about 100 tons of food each year.

I need know what the whales are feeding on today

and how energy-rich their current food resource is.

Monitoring their size and weight over time

will tell Sarah if these whales are getting enough to eat.

But tracking them is no simple task.

Bowheads are a little bit elusive.

They dive for half an hour, an hour.

You spend a lot of time waiting for them to come up again.

And then it's also, can be really difficult

to track where that whale has gone.

Okay, there he is.

Even when they find a whale,

it's hard to see its entire body.

We see what everyone else sees...

the top of the whale's head, their flukes,

sort of, a really small proportion of the whale's body.

And so that means that a lot of their behavior goes unknown.

Fortune and her colleague Bill Koski

are monitoring a group of about 80 bowheads

in Cumberland Sound.

A bowhead expert, Bill is eager to get a new perspective

on an animal he's been studying for decades.

Most of the studies I've done,

I've been flying in an airplane,

and we're circling whales at a thousand feet or so,

so that we won't affect their behavior.

Any closer, and a noisy plane spooks the whales,

who will dive and disappear.

Is he up now?

So Sarah is trying a new approach.

She's going spy on the whales

with a-state-of-the-art high-definition drone.

All right, full power. Okay.

Awesome.

The drone quietly hovers just above the whales.

They seem oblivious to the flying camera following them.

It's exactly analogous to a bird.

The same level of reaction

that you would get from a bowhead having birds overhead

is what you get with a drone being overhead.

Finally, they can see the whale in its entirety.

Its body tells a story about day-to-day life in the Arctic.

They often need to break thick ice with their heads.

And so, we'll see that they have white scars.

The scars are like fingerprints,

allowing scientists to identify and track individual whales.

The drone helps the team measure the whale

by comparing its body to the length of the boat.

That gives us an idea of how fat or how skinny an individual is.

And that's a way that we can assess their overall health.

So, are these whales getting enough food to eat?

Over time, we can monitor these animals

to see how healthy they are

in the face of a changing environment.

When the whale dives below the surface to feed,

the drone keeps an eye on it.

Because the water is so clear here,

it provides this really wonderful opportunity

to observe their behaviors over long periods of time.

Otherwise, we would just be sitting on the boat

wondering where the whale had gone.

Now, clear water and a bird's-eye view

reveal new insights into bowhead behavior.

Biologists used to think that bowheads were solitary creatures

that sometimes swam in pods, but rarely interacted.

The whales were constantly touching each other.

And before, there was no way

that we could have seen that, right?

It was illuminating to see how these animals

are more social than we could appreciate

just by observing them at the surface.

We're able to see how that whale is engaging with other animals,

how it's engaging with the environment.

So I think it has completely revolutionized our ability

to understand bowhead whale behaviors.

For scientists like Sarah, the drone is a window

into the lives of these mysterious creatures

and a way to gauge their survival in a changing climate.

When the Inuit's ancestors first settled Baffin Island

thousands of years ago,

the surrounding waters were teeming with whales.

By the late 19th century,

the commercial whaling industry had nearly wiped them out.

Today, the Inuit are among the few communities in the world

permitted to sustainably hunt bowhead whales.

The Inuit in this region take up to five whales per year.

A single bowhead will feed hundreds of people.

Sarah is sharing her research with the board

of the Hunters and Trappers Association,

which manages hunting.

They're concerned about the fate of the 6,500 bowheads

in this area of the Arctic.

If anyone has any suggestions or questions

that you think we could answer

with this technology,

that would be really helpful to know.

The images yield new insights

that intrigue even the locals,

who have lived with these whales for decades.

What part do you study in order to get the age?

Based, based on our experience with the photographs,

the amount of white just in front of the tail,

it gets more and more white as they get older.

So when you see one

with lots of white on it, you know it's a very old whale,

probably 150 years or so.

Knowing the size and age of the whales around here

helps locals plan for hunts

that leave enough whales in the ocean for future generations.

There's one question

that fascinates both locals and scientists.

Year after year, the bowheads gravitate toward the shore

and hang around the big rocks there.

No one knows why.

Sarah is hoping the drone will explain a mystery

first recorded more than 170 years ago.

Ricky Killabuck, an Inuit fisherman,

brings them to the site.

So have you seen any whales in this bay this year?

- Oh, yeah, yeah. - Yeah? Okay.

If you go back to the whaling records dating back to 1845,

whalers had made note