[soft music] - Hi there, I'm Frank Graff.

North Carolina's coast has been a magnet for explorers and tourists alike.

It's also where wild horses have been roaming the beach for centuries.

We're gonna take a new look at the wild horses on the Outer Banks coming up on Sci Nc.

- [Announcer] This program was made possible by contribution to your PBS station by viewers like you.

- [Announcer] Additional funding for the Sci Nc series is provided by gsk.

[upbeat music] - Hi again, and welcome to Sci Nc.

The images of the wild horses on the Outer Banks, fill tourism brochures their stories are legends but there's a lot of science behind it all.

Our story is from "Overview", a series produced by PBS North Carolina for PBS Digital Studios.

- [Announcer] These are the wild horses of the Outer Banks.

Locals call them banker horses.

They've managed to survive here for more than five centuries, but they're not technically supposed to be here.

Some view these horses as symbols of the American spirit, others as a beloved landmark of the local community but many view them as an invasive pest and one that's damaging a fragile landscape.

So what do we do when an invasive species becomes an Instagram star?

Ah.. living by the ocean sounds pretty nice, but surviving on this thin sliver of sand off the coast of North Carolina isn't easy.

Banker horses endure powerful storms and hoards of summer tourists.

But how did they get here?

Horses have a curious origin story.

Fossils tell us their ancestors actually originated in North America around 30 million years ago and spread to other continents over the Bering land bridge.

But then the ancestors of horses died out in North America.

The modern day species only returned to the continent thousands of years later when European colonizers brought them back.

Europeans also brought with them, pigs, cattle, and rats along with a host of dangerous germs none of which were native to the continent.

Over the past five centuries these species have wreaked havoc on the landscapes ecosystems and people that were already here.

But the way we treat wild horses is very different from the way we treat wild pigs, for example.

Okay you very cute, but you're also a scourge and a nuisance wild horses and wild pigs are both feral, meaning they were once domesticated animals that broke free to live in the wild and they can both cause a lot of destruction to landscapes when there's too many of them.

On the Outer Banks, wildlife officials shoot feral pigs from helicopters to control their numbers.

In contrast, these horses all have names and are famous on Instagram.

They're island celebrities and they even have a cool origin story.

Supposedly the descendants of horses that swam ashore from Spanish shipwrecks in the 15th century populating this chain of islands that hugs the North Carolina coast.

So are horses a re-introduced native species or are they invasive?

Those are questions without clear answers.

- [Meg] You sort of have to stop and ask yourself at what point does a species become maybe not native but they're not invasive.

- Meg Puckett manages the Corolla herd one of three large herds that roam the Outer Banks.

It's her job to decide what happens to these horses.

Horses pose a unique challenge on barrier islands.

Barrier islands are the first line of defense against hurricanes, but they're increasingly threatened by sea level rise and human development.

Some of these islands are only a mile wide.

Yet population growth around here is twice the national average.

So human development is pushing from one direction and sea level rise from the other causing what's called a coastal squeeze.

Now take all the pressures these islands already face and add a herd of dune trampoline plant eating horses.

You see plants are vital to barrier islands.

They clean the water, help anchor the dunes from erosion, and provide habitat for birds and fish.

Too many horses can mean serious damage to the vegetation, and that makes the Island more vulnerable to erosion and storms.

There's a cautionary tale out West where a different population of problematic ponies, the beloved wild Mustangs have gotten so numerous that they're gobbling up resources from other species and costing the federal government more than $80 million to manage every year.

Here in the islands the herds are smaller, but there's another problem.

More horses attract more tourists and humans really want to get close to them.

It's illegal to approach a wild horse because if a horse feels threatened, well, I don't know if you've ever seen a horse kick, but it's not a fun time.

You can get seriously hurt and humans put the horses in danger too.

Almost every summer a wild horse is either hit by a car or fed something that makes them seriously ill. - [Meg] I got sent a Tik Tok video yesterday of a girl sitting crouched down in front of the horse with her hands around his head.

I really doubt that she meant anything bad by it I don't think she didn't realize that she was being harmful, but she was.

- [Announcer] Social media has fueled the public's fascination with wild animals, not just here, but around the world.

On one hand, it raises awareness of potentially threatened or endangered species but it also creates pressure to exploit or sometimes even remove animals from their habitat to serve as props for selfies.

This desire to be close to wild animals has led to injury and death for some of these very horses.

Meg's challenge is to manage both horses and people.

- [Meg] It's one of those things where you just have to find that balance.

And we know that if the horses are left to breed uncontrolled, number one, we're gonna have a population that's not sustainable.

Number two, you start to see really bad in breeding.

We will starting to see really bad genetic issues and birth defects with the fold.

- [Announcer] Part of that management is horse birth control.

Meg can keep the herds numbers down with contraceptive darting.

Essentially she uses a dart gun to shoot fertile mares with birth control.

[gun shots] It stings a little, but not more than a fly bite.

The humans are a little harder to control.

- [Meg] We're seeing so many more people visit the North beaches that had never been here before.

And so they don't know the history they don't really know the rules and the reasons why we have those rules and why they're so important.

So our education and public outreach efforts have really been stepped up the past couple of years.

- [Announcer] Unlike feral pigs or rats humans have decided it's worth the effort to keep these sort of wild horses around.

The solution is essentially to keep them from being too wild.

- [Meg] Yeah, your definition of wild might have to change a little, but we still work to do everything we can to let the horses live in natural life.

- [Announcer] For now, it's up to the humans and the horses to keep a healthy distance not too far and not too close and find a balance so that we can preserve this place and make sure that in a hundred or 500 years from now there are still islands to call home for us and the horses.

[techno music] ♪ - Wild horses had been on the beach for centuries but that's nothing compared to the 450 million years that horseshoe crabs has been around.

You've probably spotted them walking the beach.

Science producer Rossi Islar shows us how the blood from these living fossils plays a vital role in developing new medicines and vaccines.

- [Rossi] Hi, friend, he's like, what are you doing?

Please put me down.

- [Rossi] Here's a horseshoe crab a creature that's been around for 400 million years.

And here's Rachel the scientist who's trying to figure out a way to raise them.

- If you can see that hole, that's open up there.

That's her mouth and it's surrounded by these toothbrush-like bristles, and they don't have teeth, so what they do is they grab onto the food they walk with it, they grind that food and they ingest it.

- It's like a litte... yeah.. - That's right.

- .. a little eating orfice there.

[laughter] - So this is care it's backyard urban aquaponic farm in the heart of Durham, North Carolina.

♪ - Can you explain how horseshoe crabs and urban farming come together?

- So kind of a perfect animal to integrate into the system because it could potentially be a high profit margin animal as well as an animal that we should be thinking about conserving.

Horseshoe crabs are big money to the biomedical industry.

Every time you get a flu shot you should probably thank a horseshoe crab basically any medical device or drug that goes into your body.

Think vaccines, pacemakers, hip replacements has been tested using the blood of horseshoe crabs.

Yes, that's horseshoe crab blood.

The copper in their blood gives it that bright blue color but that isn't the only thing that's special about it.

Horseshoe crab blood clots almost immediately when it's exposed to dangerous bacteria or fungi.

It's part of the reason horseshoe crabs have outlasted the dinosaurs.

But it's also the reason the biomedical industry depends on horseshoe crabs to make sure their products won't cause infections.

- Fishing participants will go out collect the crabs and put them in a boat.

They'll transport it in a truck back to the facility and they will then bend the crab in such a way that you have access to that membrane to do the bleeding.

- A horseshoe maybe that's twice as size of this one to the industry is worth about $1,800.

They don't even get a cookie or orange juice after they give blood like we do.

So, what happens to these creatures once they're released back in the wild nobody knows.

They're not tagged.

- You become so attached to these animals.

I don't know what it is but how can you become attached to a creature that looks like that?

- I don't know.

- You have a soft heart.

- [Rossi] Bleeding horseshoe crabs doesn't kill them and companies only take 30% of the crabs blood in exchange millions of lives are saved from diseases like sepsis.

But according to research from Kepley Biosystems in some areas of the US the combination of bleeding over-harvesting and habitat destruction has caused a 95% decline of spawning horseshoe, crabs.

So horseshoe, crabs are stressed out?

- They are really stressed out.

We want to offer a new way to collect horseshoe crabs by you're not pulling them from the wild but you are actually maintaining them in a managed closed system, a trackable one.

So we know which horseshoe crab was being bled.

- [Rossi] Rachel says it's difficult to keep horseshoe crabs alive longer than six months.

And she thinks it's because of their diet.

So she and her team from Kepley Biosystems are experimenting with types of food.

- [Rachel] So, yeah they're receiving a very well balanced diet to keep them healthy and happy.

- [Rossi] The team's goal is to teach farmers how to raise horseshoe crabs.

So instead of pulling crabs out of the wild the biomedical industry can rely on farmers instead.

- Is it lunchtime?

Tail's wagging he's happy.

Is that what that means.

We can potentially set up contract farming to integrate them into their farming system, because God knows farmers need to have more profitable revenue.

You want some?

You hungry, hm?

Just kind of flip them over that way, hold them from that side so the hinge doesn't basically pinch you.

- Snap yeah.

- Yeah.

- [Rossi] But for now we expressed our gratitude to the humble horseshoe crab by giving him some treats.

- Yes, it literally is the Sarlacc Pit from star Wars.

[chuckling] - He likes the worms.

- Okay, buddy, ciao.

[humming Star Wars theme] [chuckling] [techno music] - [Announcer] Do you want you to explore more cool science facts and beautiful images of North Carolina?

Follow us on Instagram.

- Horseshoe crabs, not cute.

Groundhogs on the other hand, are cute.

And like horseshoe crabs, they too are a medical marvel.

Meet the woodchuck, otherwise known as the groundhog.

- So it depends on where you live woodchuck and groundhog are two different names for the same species and the species is Marmota Monax.

- [Announcer] And Dr. Breton woods loves groundhogs or woodchucks.

- Don't just say that, "Oh they're cute".

They're very cute!

[laughs] As animals go there I mean, they're practically teddy bears walking around doing cool things, yeah.

[laughs] - And by the way, woodchucks, or groundhogs are pretty well known.

There's that pseudo holidays centered on Groundhog's shadows and weather forecasting.

There's that movie centered around that weather forecasting "Holiday".

There's also a rhyme.

- How much wood could woodchuck chuck.. - ..if a woodchuck.. - ..could chuck wood?

- [Announcer] And a commercial about that rhyme.

- Mm?

- Hey you dang woodchucks!

Quit chuckin my wood!

- But back to the science of what makes marmots cool.

- They have almost two different types of physiologies.

They have their physiology they have through the summer, They have the physiology they have during the winter, for hibernation.

So it's almost like two animals in one.

- And those different physiologies are all because marmotas hibernate.

- [Dr. Wood] Their body, temperature drops, their metabolic rate drops, their breathing slows down, they could be as low as a couple of breaths of per minute.

- We're not talking hibernation like a bear, which is essentially a deep sleep.

Marmots go underground and spend the winter in in what's really a state of suspended animation.

- And so imagine that you're a human and you hibernate, and you're gonna go for say six months without eating, drinking, and you're essentially gonna be maybe in your bed for that entire time.

And you go in at 200 pounds, and at the end of that six months you come out a hundred pounds.

- She has a lot of coccidian parasites that are in the protozoan stage right now.

- [Announcer] Dr. Woods and his students at High Point University believe understanding how marmots survive hibernation could provide huge benefits for human health.

- Before they enter hibernation in the winter months during the summer and spring, they feed they gain weight but then they're able to expel those parasites before they go into the cycle.

- Blood and fecal samples are providing insights.

- So what my job was during the summer was to figure out, well what types of parasites could be in these groundhogs before they enter the hibernation period?

- There's also the question of marmot blood.

- We're thinking about how they can cool their body temperatures to almost freezing temperatures and they can turn on their bodies like that and they can reheat their body and the blood is fine.

So we would hope to be able to mirror that in the future with human blood.

If we could maybe figure out how to refrigerate human blood we could extend the shelf life.

- So let me run through why marmotas are great.

So we've established that they're cute animals.

A marmot can double, or in some cases especially with young triple its mass in a couple months they can lose half of its mass or more than half of its mass in hibernation.

And they'll do that every year.

Can you imagine if a human did that on a regular basis?

And so what would normally go wrong?

Well, blood will clot because it's not moving very much.

When you have that much fat when you have that much sugar in your system, damage tissue I dare say a fair number of people would probably die if they were forced to do something like that.

So it seems as if they have all of these issues and solutions for them.

And so what does the marmot do that protects it from these things that we know can be very damaging to our tissues?

[techno music] - [Announcer] Wanna take a deeper dive on current science topics?

Check out our weekly science blog ♪ - So what do you get when you combine an insect researcher and a photographer?

Well, take a look at the work of Adrian Smith at the North Carolina Museum of Natural Sciences.

[gentle music] - 300 million years ago before birds, bats and even pterodactyls, insects are flying.

They were the first animals lift themselves into the air and they're still the most successful fliers on earth.

Lately, I've been putting insects in this little platform here and filming how they get up into the air and begin their flights.

There are millions of species of insects and only a tiny fraction of them have ever been filmed flying before.

So I've been trying to get the most interesting insects I could and film them in a way that no one else has.

Almost all the insects that you'll see in this video were collected by setting up a black light at night.

A lot of night active insects will come to these lights and this way I've been able to collect and film insects across seven different orders.

Most of this was filmed working from home and this is a filming set set up in my laundry room.

All the sequences you'll see were captured here filming at a rate of 3,200 frames per second.

I specifically avoided filming things you might've seen in flight before.

So there's no butterflies, there's no bees, there's not even a fly in this video It's only the weird stuff.

Like for instance, this was my half successful attempt to getting a plume moth to fly on camera.

I couldn't get it to fly in frame without prodding it with a paintbrush.

These are really unique moths and I love how it seems to just barely be able to lift itself into the air, and check out the unusual kind of feather like hind wings.

♪ I'm gonna have to try to film more of those moths.

They're really interesting.

Okay, let's start with an iconic summertime insect, one you're probably familiar with, but you probably haven't seen like this.

This is a common eastern firefly or lightning bug.

Like most beetles getting ready to fly.

The first step is lifting the hardened protective four wings called the elytra so that the hind rigs can unfold and start flapping.

Although, one interesting thing that this footage shows is that the elytra flap during flight too.

And getting off the ground the middle legs are just barely out of the path of the wings as they flap nearly 180 degrees around the body.

The wings actually brushed up against each other at the top and bottom of the stroke.

In these scenes the beatles are beating their wings at a frequency of about 62 full up and down strokes per second.

This a painted liken moth two flight sequences from the same individuals superimposed.

This might be my new favorite piece of insect footage the lighting and the slow motion make it look almost unreal like animated or made out of clay or something.

One of the things I love in that sequence is seeing how flexible the wings are here at the end of the downstroke.

When the wings are turning back up to the upstroke, the tips of the four wings collapse and roll up under the wings they flatten back out as a wings are lifted back up and remain flat for the whole downstroke.

Some moths like this leaf roller get into the air by combining a downstroke of their wings with a jump powered by the middle and hind legs.

Their wing tips also flex and fold at the beginning of the upstroke when they being raised back up.

Now this is a rosy maple moth.

It doesn't jump or roll up it's wing tips like the others but honestly, who really cares, just look at it.

It's clearly the best moth.

It looks like a flying muppet.

Like after it flies off the screen here it's probably going all the way back to living it's life on Fraggle Rock.

Okay now, for some more unusual stuff, this is a species of common stone fly.

Look at this thing as a spectacular jump, absolutely gigantic hind wings and go straight up and over right into a beautiful swan dive.

Immature stone flies are aquatic and adults hang around the water too.

Adults of some species are known to use their wings for skimming themselves across the water.

Another aquatic insect is this mayfly.

Mayflies are an ancient lineage of insects dating back to at least the Permian over 250 million years ago.

Currently stoneflies and mayflies are a source of debate in the insect fossil record.

In 2011, this fossil was published, which dates back to around 305 million years ago.

It's the oldest full body impression of a winged insect.

The original researchers described it as a mayfly.

However others have claimed it actually better represents a surface skimming stonefly.

This is the biggest insect I've filmed.

It's another one which spends most of its life as an immature aquatic organism.

This is a fish fly Right to take off this individual is flapping its wings at a relatively slow rate of 11 beats per second.

That's in the frequency range what big slow flapping butterflies do.

And they're usually using their wings to alternate between a powered flight and a glide.

The front wing of that fish fly is 37.6 millimeters long nearly 10 times bigger than the four millimeter long wing of the next insect, an aphid.

Unlike most of the other insects that you've seen it doesn't seem to jump to get in the air wing flapping just kind of picks it straight off the ground without the legs moving.

The oddest part about this aphid fly is that every upstroke rotates the body counter-clockwise like watch the sequence again and every upstroke notice how the body ratchets backwards like the second hand of a clock in reverse.

Here is three more sequences super-imposed and all of them, you can see that same body rotation happen on every upstream of the wing beat.

This last insect is a scorpion fly.

They throw themselves into the air with a four legged jump.

I love how this one gets in air throws its legs up and just kinda turns and stares down the camera.

that scorpion like tail means that this individual is a male.

Although it kinda looks like a stinger that's actually the mating appendage.

Is it a slow motion insect footage the best?

What I thought was incredible was how different flight looks across insects.

There's definitely more to it than just flapping wings.

We have so much left to study and learn from these organisms and how they figured out the best ways to navigate through the air.

[techno music] - [Announcer] Hey, parents, teachers and homeschooler looking for lesson plans, you'll find free interactive ones about all types of science covered by Sci Nc online.

- And that's it for Sci Nc for this week, I'm Frank Graff.

Thanks for watching.

[techno music] ♪ - [Frank] Want more Sci Nc?

Visit us online.

♪ - [Announcer] Additional funding for the Sci Nc series is provided by gsk.