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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?

[seagulls cawing] [sighs] 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 hordes 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 are 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 reintroduced native species or are they invasive?

Those are questions without clear answers.

(speaker) You sort of have to stop and ask yourself, at what point does a species become--it-- maybe not native, but they're not invasive?

(narrator) 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-trampling, 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 could 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. (Puckett) I got sent a TikTok video yesterday of a girl sitting, crouched down in front of a horse with her hands around his head.

I really doubt that she meant anything bad by it.

I don't think-- you know, she didn't realize that she was being harmful, but she was.

(narrator) 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, 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.

(Puckett) 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 going to have a population that's not sustainable; number two, you start to see really bad inbreeding.

We were starting to see really bad genetic issues and birth defects with the foal.

(narrator) Part of that management is horse birth control.

Meg can keep the herd's numbers down with contraceptive darting.

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

It stings a little, but not more than a fly bite.

The humans are a little harder to control.

(Puckett) We're seeing so many more people visit the north beaches that have 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.

(narrator) 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.

(Puckett) 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 a natural life.

(narrator) 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 100 or 500 years from now, there are still islands to call home for us and the horses.

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