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

Saving North Carolina's largest freshwater lake.

Scientist, Adrian Smith introduces us to an antlion.

And, up close with red wolves.

The endangered animal is only found in a tiny part of North Carolina.

Those stories and more coming up on Sci NC.

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

[gentle music] - [Announcer] Additional funding for the Sci NC series is provided by GSK.

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

You know, the last home in the wild for the red wolf is the Alligator River National Wildlife Refuge in Eastern North Carolina.

A federal reintroduction program brought the number up to about a hundred wolves several years ago.

Researchers now believe that only about 30 animals remain in the wild.

The documentary filmmakers at Running Wild Media captured amazing footage of those remaining red wolves.

[gentle music] - [Narrator] On the coast of North Carolina remains the last wild population of red wolves in the world.

An animal so secretive, many people are unaware that it even exists.

Living entirely within a single refuge, the Milltail Pack is the largest of the three remaining packs of this Eastern wolf.

Due to their low numbers, U.S.

Fish and Wildlife monitors them from the sky and the ground to protect this species from a second extinction.

- So many people don't realize that red wolves are a thing, and unfortunately that goes for locally as well.

They're just a magnificent animal.

So, we've currently got 17 radio collared red wolves, at the Alligator River National Wildlife Refuge.

Based on the strength of the beat, you can kind of get a sense for what direction they are and how far they are.

The problem we have right now is that our red wolf population is so low.

[radio static buzzing] I'm not picking up anybody here.

Dang it.

- [Narrator] Red wolves once roamed throughout the Southeastern United States and numbered in the thousands, but when the human population increased much of that wilderness was lost.

Many people feared the wolf.

Those fears led to government sponsored extermination programs.

[sad music] - The red wolf was first listed as in danger of extinction under the Endangered Species Preservation Act in 1967 and between 1973 and 1980, the few remaining red wolves were captured to begin a captive breeding program.

- [Narrator] Due to their importance in the ecosystem, the new goal was to rebuild the red wolf population, but in 1980, they were officially declared extinct in the wild.

This meant that the entire survival of the species was dependent upon managed breeding programs - Nothing like this had ever been done before with a large carnivore species, with the intention of getting the numbers up and releasing them back onto the landscape, to save an endangered species.

- [Narrator] Before release, the wolves are outfitted with radio collars that allow biologists to study them from a distance.

The radio permitted hands-off monitoring of the wolves since each collar contains a transmitter which will help locate the wolf on the landscape.

A deer killed on a nearby road is set out as a going away present.

At last, this first pair of wolves will get a chance to make it on their own.

- The innovative techniques that were developed as part of the red wolf recovery program led to the successful re-introduction of red wolves in North Carolina, but not only did it do that, it paved the way for other gray wolf, Mexican wolf, reintroduction programs.

It was the first re-introduction for large carnivore on the landscape.

This happened eight years before the gray wolf reintroduction in Yellowstone.

- We're here near Yellowstone National Park because the gray wolf reintroduction that happened here in 1995 was built on what was learned from the Red Wolf Reintroduction Project that happened in the 1980s - [Douglass] We reintroduced 41 wolves.

It was an experience of a lifetime.

It really has flipped Yellowstone.

It's changed the ecosystem.

It's very important to spread this word that wolves aren't where people used to think, but they are very important inhabitants to ecosystems.

[wolves howling] - [Narrator] What we've learned from recovery efforts of gray wolves in Yellowstone National Park has been an important lesson when trying to save other endangered carnivores, like the American red wolf.

- Life is constructed in kind of like a triangle, where you have very few species at the top and a lot of species at the bottom, and wolves sit at the top and they eat species from the next level down, which they're more of.

And then they eat the species at the next level down below that.

So nature is all interconnected and when you take those few species out at the top, it changes everything and what people did is we came along and we took them out.

And so when you don't have these carnivores, the plant eater's population explode and they overeat the vegetation, when they overeat the vegetation any other animal that uses that vegetation doesn't have habitat.

Wolf predation is built on vulnerability and weakness.

In general, they cannot go out and kill any elk or deer.

If that animal's healthy their chances of killing it are very low.

In fact, in Yellowstone, wolf success rate on elk is five to 15%, they live on the weak animals.

It's a myth that wolves show up and my hunting is gone.

You're hunting, maybe better.

Humans tend to take the healthy.

Wolves tend to take the weak.

- By removing that sick animal from the herd, it's removing that disease from being spread to the rest of the herd and there's also some evidence that that disease, blue tongue, brucellosis, by removing those diseases from the landscape they can actually stop that from transmitting to our livestock.

[gentle music] For decades the red wolf program flourished.

The red wolves grew, they bred, they got up to almost about 150 red wolves in the wild.

Just a few years ago, some anti-wolf movement spreading misinformation really changed that landscape there for them and made it very hard to do conservation and increased poaching, increased the loss of the species, and we're down to just about 30 in the wild today.

You think of what we've dealt with in our culture, portraying this wolf as the big bad wolf, and that's our job is to be able to talk about what wolves are actually like.

Wolves are very shy.

They want to run away from people.

Another challenge that the red wolf faces is that when their numbers are really low, they may hybridize with coyotes.

When Europeans moved into the United States they eradicated the gray wolf and the red wolf from the ecosystem.

The coyotes took that as, I'm going to move wherever I want to now, because they didn't have wolves there to keep them in check.

- The concern of hybridization between red wolves and coyotes can be alleviated with a large enough red wolf population size in the wild.

- [Regina] But when their numbers got so low and they were desperate and couldn't find another red wolf to breed with and they saw a coyote down the street, they're going to choose that coyote to breed with.

[gentle music] - [Bridgett] Once the wild population of red wolves is large enough this will allow red wolves to very easily identify other red wolves as mates and this will exclude any possibility for hybridization.

- I'm gonna try a few more signals from here and see if we can pick up some members of the Milltail pack.

The biggest thing I want people to know about red wolves, quite honestly, is that they actually exist.

You know, I live here locally and it's incumbent upon us to get that message out.

I gotta find these guys for my own peace of mind.

- The fundamental question is, do humans have a right to take over the planet?

This is a real test for our will to live with other species.

- [Regina] A lot of people think things like, they're going to decimate prey populations, they're going to decimate livestock, and what we've seen with recovery efforts, is that that's not actually the case.

- [Narrator] By restoring American red wolves back to the Southeastern United States, we can restore balance to their ecosystem.

The Red Wolf Species Survival Plan is made up of 43 institutions across the United States that are all working together to help save the American red wolf.

By breeding animals and enclosures that could be rereleased one day, conducting important research on red wolf behavior and educating the public, they help spread awareness about this amazing species.

In managed care, animal care staff across the various institutions involved in the Red Wolf Species Survival Plan Program, raise the red wolves in a way that does not habituate them to humans by avoiding contact with the red wolves.

- Wolves are naturally afraid of people, and that's a huge survival skill that we want to make sure they maintain, so when they get the call to be released back out into the wild, they have survival skills to not only stay away from people, but we feed them natural prey, like white tail deer.

They have puppies so they learn how to raise a litter and they learn how to be a pack, a family, that can survive out in the wild.

- [Narrator] The only time animal care staff is hands-on is to administer vaccines, and while it is a little intimidating for the pups, it reinforces wolf's natural inclination to run away from humans.

- Got it.

- Nice job.

All right you guys, collapse up here.

- Ready?

We're going to go in real quick and make sure the puppies are in the den as they should be.

It's the little one.

It's the little one.

[indistinct talking] Oh man, we're so feisty.

- [Regina] What these pups represent is hope for the American red wolf.

Every pup born in the breeding program has a chance to help with the future re-introduction of the red wolf back into its native habitat.

[wind whooshing] [radio static buzzing] - Did you hear it for a second?

Yep.

That's it.

[scanner clicking] There you go, that's good, buddy.

So that is, it's a male wolf, 2186, born in 2016.

So he's getting ready to be a 3 year old male.

[gentle music] Yay.

We do need to get the word out about how wonderful they are and that we hope to preserve and grow this population both locally and hopefully in the future in other areas so we can have a true wild population.

The people of the Fish and Wildlife Service and myself and the biologists, we believe in this species, we have dedicated years, some of us a few years, some of us 30 years of our lives to this species and this country.

It would be remiss to not have this species on the ground.

It most definitely can be done.

I definitely believe that.

- I absolutely think red wolves need to be conserved.

- [Regina] What conservation organizations are working towards now is to help bring the species back to the Southeastern United States, to help restore the American landscape.

Our vision is a place where we have red wolves in the future, where my kids can go out into the wild and hear a red wolf howl.

[wolves howling] Think about how often we talk to other countries and say, "You need to save your rhino or your elephant," and here in our own backyard, the red wolf is one of the most endangered mammals in the entire planet.

Restoring the red wolf back to the American landscape will create a healthier environment for every living thing.

[upbeat music] - [Announcer] Do you want to explore more cool science facts and beautiful images of North Carolina?

Follow us on Instagram.

- Lake Waccamaw is North Carolina's largest freshwater lake.

It is beautiful and the variety of fish and mussels call it home.

But years ago, an invasive aquatic plant threatened to take over the lake and kill almost everything in it.

Students from the UNC Hussman School of Journalism and Media explain what happened next.

- [A.J.]

State biologists consider Lake Waccamaw a jewel of biodiversity.

Two rare species of mussels live here as well as three species of fish and two species of snails found nowhere else in the world.

Wildlife biologist, Brena Jones monitors these species annually to track their numbers.

She knows just where to look.

- The silverside is, it prefers open-water.

However, the killifish and the darter are usually found closer to shore.

The darters really like these emergent maidencane beds.

They hide in there among all the stalks and the killifish just move into any cover they can find.

The mussels can be found throughout the lake in all depths of water.

They settle in the bottom and feed on organic material and algae and bacteria down there.

And the snails too can be found anywhere in the lake.

- [A.J.]

Lake Waccamaw is what's known as a Carolina bay and not because it's an inlet to the sea.

- It actually comes from three bay trees, loblolly bay, sweet bay and red bay are the common bay trees you'll find in and around a Carolina bay.

- [A.J.]

Lake Waccamaw is the largest bay lake in North Carolina but that's not all that sets it apart.

The water in most bay lakes is acidic.

The water in Lake Waccamaw is not.

- So, what you see here is the limestone bluff that's located on the north shore of Lake Waccamaw.

There are four creeks that feed into the lake that are highly filled with what we call tannic acid, that's what gives the lake it's dark tea color.

This acidity is neutralized by this bluff here which gives the lake a neutral pH.

That is for the extreme bio-diversity that you see out here in the lake.

As far as total species in the lake that we have is 15 mussel species, two of them only being native for Lake Waccamaw.

54 fish in this lake, with three fish only found in Lake Waccamaw.

And then we have 11 species of freshwater snails, two freshwater snails, only native to this lake.

- [A.J.]

But in 2012, that biodiversity faced a foreign invader, an aquatic plant called hydrilla, native to Asia and Africa.

- Hydrilla was one of those things that kept me up a lot of nights.

It was a very scary situation.

- [A.J.]

Hydrilla robs the lake of oxygen.

North Carolina state researchers found the plant covered more than 10% of Lake Waccamaw, putting the lake's seven unique species in danger.

- So it certainly would have choked out all the lake habitat.

It would have just been solid hydrilla, the entire water column solid flatbed across the surface.

- We are almost sure that the hydrilla came because people brought their boats from other lakes.

- [A.J.]

Boats can carry the invasive plant from one body of water to another, says Julie Stocks, a volunteer for Coastal Carolina University who checks water quality in Lake Waccamaw.

- And the hydrilla, tt's very difficult to get rid of because they have tubers that settle in the bottom of, it's like a potato tuber, in the bottom of the lake and it stays there and you can kill off the top but then the tuber's still there.

- [A.J.]

After hydrilla's discovery in 2012, officials were unsure how to cope with the invader.

- Should we use chemicals?

Should we use kind of a carp, like a big goldfish, to eat it?

Should we drain the lake?

[ducks quacking] - [A.J.]

Officials chose to use a chemical called fluridone that they felt wouldn't hurt the lake's native species.

- We didn't want to use anything that was a copper based product.

Copper is a big one that we were worried about that would be infused into the soils that would affect the mussel species here.

But this herbicide has been successful in just attacking hydrilla, to make sure it's fully eradicated.

- [A.J.]

The town of Lake Waccamaw, Columbus County, and the State, paid for a 10 year treatment plan that started in 2013.

Over the past six years, fluridone treatments have cost more than $3 million.

- We were a little nervous about how it might affect our samples and we could not tell, even the day they put the fluridone in the water, we could not tell any difference in the samples that we had had the year before.

- [A.J.]

Officials say they found no hydrilla in the lake in 2019, that makes former town manager, Harry Foley, happy.

- When it comes to the treatment of hydrilla, think that's been one of the best things that the state of North Carolina was able to do for Columbus County and Lake Waccamaw.

It's working, I think that the test results speak for themselves.

- [A.J.]

State biologists and park officials say there's a lesson to learn here.

Hydrilla can threaten any lake in the state.

To prevent that from happening, boaters must wash their boats before entering and after leaving new bodies of water.

Boaters must also empty and wash holding tanks they use for fish catches.

Just one tiny piece of hydrilla can multiply to infest an entire lake.

That didn't happen in Lake Waccamaw but a return of hydrilla still is a threat.

- So we have mussels, fish, and snails that are native only to this lake, they're found nowhere else in the world.

So it's very, very important to protect these species because when they're gone, they're gone.

[upbeat music] - [Announcer] Want to take a deeper dive on current science topics?

Check out our weekly science blog.

- Have you ever walked along the sandy area and noticed little indentations at your feet, almost as if dozens of volcanoes or geysers are suddenly going to erupt?

Well, it's not geography or geology.

It's entomology.

This creature, scientist, Adrian Smith at the North Carolina Museum of Natural Sciences introduces us to the antlion.

- Have you ever looked under a picnic table or the overhang of a porch and seen this?

Cone shape pits spread across the soil?

These are made by one of my favorite insects, antlions.

An antlion is a type of insect that's famous for what it does as a larva.

In fact, most of its life is spent in a larval form, and if you've never seen what a larval antlion looks like and what it does, you're in for a treat.

[playful music] This is a larval antlion.

Another common name for this type of insect is a doodlebug.

It has that name because it does this.

When it's looking for a place to make that cone shaped pit it scoots backwards, leaving doodle-like squiggles.

[playful music continues] As it tunnels through the soil, it uses its head and giant jaws as a shovel, flinging sand as it goes along.

It digs a pit by scooting backwards in a circle, spiraling down until it's positioned itself at the bottom of the pit with its jaws wide open.

From there, it sits and waits for this to happen.

When an ant stumbles into the pit, it struggles to climb up the sides, slipping on loose sand with each footstep.

The sprinkle of sand from the struggling ant gets the antlion's attention.

In response, it flings more sand up at the ant causing it to lose its footing and slide down into the center of the pit.

At the center, the antlion springs into action with its massive jaws, grabbing and clamping down on the prey.

The antlion's jaws end in needle-like points that inject digestive enzymes, these enzymes kill the ant and break down internal tissues enough to where the antlion can suck its prey dry.

Sometimes, the prey is dragged underground for feeding or just kept at the surface.

But at the end, the body is brought up and thrown up and out of the pit.

Aren't antlion's amazing?

But not all ants are helpless prey to falling in an antlion pit.

One ant that I've studied for many years has an amazing way of escaping.

It's called a trap-jaw ant.

[playful music] Trap-jaw ants have spring-loaded jaws that they can snap shut at incredible speeds to capture prey or defend themselves.

We don't have them here in North Carolina, but further south, in Georgia and Florida, they're a common insect predator, and against softer bodied insect prey, their jaws are effective hunting weapons.

[playful music continues] When they find themselves at the bottom of a pit, they don't use their jaws to fight the antlion.

Instead, they aim their heads down and snap against the ground.

The force from their spring-loaded jaws reflects back at them and sends them flying up and out of the pit and away from danger.

Sometimes they only have fractions of a second to perform these escape jumps and avoid the jaws of the antlion.

But, if they end up being caught, their jaws snaps become ineffective and the trap-jaw ant becomes just another meal for the antlion.

Underground, at the bottom of the pit, the antlion sheds its skin as it grows, molting into to a larger, more advanced larval stage.

In the last larval stage, the antlion will encase itself in a ball-shaped cocoon made of silk and sand.

After weeks in this cocoon, a winged adult, which looks nothing like the larva, will burrow its way out.

[suspenseful music] When the adult makes its way out, it scrambles to climb up and off the ground to the nearest perch.

From there, it inflates it's wings and expands its body by circulating fluids and pumping it's insect blood or hemolymph.

Although the adult form kind of looks like a dragonfly or a damselfly, antlions are not related to those insects.

In fact, in comparison to them, adult antlions are really bad at flying.

There are different species of antlions and they all change into this slender, delicate flying form in their adult stage.

But really, the adult stage is only a short footnote in their total lifespan.

The antlion's journey from a voracious predatory larva to a delicate fluttering adult is one of the most dramatic stories of change that can happen across the life cycle of an insect.

- [Announcer] Hey parents, teachers, and home-schoolers, looking for lesson plans?

You'll find free interactive ones about all types of science covered by Sci NC online.

[quirky music] - And that's it for Sci NC, I'm Frank Graff.

Thanks for watching.

[upbeat music] ♪ - [Announcer] Want more Sci NC?

Visit us online.

- [Announcer] Additional funding for the Sci NC series is provided by GSK.