- Does anyone need flashlights or magnifying glasses?

We have a few left.

- [Michelle] This park is about to close for the night, but dozens of people are just arriving to go for a hike.

- There are his real little legs right there.

And here are his pro legs.

They're not really legs.

The inchworms only have them at the top and the bottom.

- I've learned so many things already tonight.

- Awesome.

- [Michelle] It's a muggy summer evening, and all of these people have turned out to walk around in the swampy woods in the dark looking for bugs, specifically moths.

- Who here has been to a moth night event before?

Okay, so a lot of you have not done a moth night.

That's great.

Hopefully we'll have a lot of fun.

It will be buggy, but that is kind of the point.

We're currently in southwest Durham County.

We are in the New Hope Creek watershed.

So New Hope Creek starts up in Orange County.

It goes through this part of the county.

It goes down to Jordan Lake.

That eventually goes in the Cape Fear River and down into the ocean.

So it's a very important watershed for much of North Carolina.

- [Michelle] Tonight, Moth Night is taking people into the New Hope Creek Bottomland Forest, a diverse natural habitat in the middle of an urban area.

Researchers like David have been documenting the biodiversity in the area and have some good news and some bad news.

- We found some pretty disturbing lack of species, especially moth diversity.

And we're not entirely sure why that is, but there's a lot of factors.

Light pollution, especially for night-flying insects, is probably a big factor.

There's a lot of development right up against the edges of this, and they're actually probably trying to develop more.

There's pesticides, there's invasive plants, but this is kind of the case all over the state and all over the world.

We're in the middle of what people have called an insect apocalypse, which is as bad as it sounds.

We're losing diversity, losing numbers of moths and other insects at a really rapid rate.

I probably don't have to tell you that that's not gonna be good.

- [Michelle] Insects are the most common animals on our planet, with over 1.5 million named species.

And they play important roles as pollinators, decomposers, natural pest controllers, and as the sole food source for many animals.

Even tiny birds like the chickadee need a large number of insects to survive.

One nest of chickadees requires 6,000 to 9,000 caterpillars to survive to the point of fledging.

And caterpillars are the larval stage of members of the insect order Lepidoptera, which includes butterflies and moths.

- We'll go ahead and start heading down here.

We're about to go onto the Bottomlands Trail.

This goes eventually into New Hope Creek Preserve, which is a county preserve.

It's a few hundred acres that we, the Open Space Program, maintain.

All that protection happens partly 'cause of government and partly 'cause of conservation professionals, but really first and foremost because of citizen action over decades and decades.

The reason we still have a good bit of biodiversity here, even though it faces a lot of challenges, is because of that action and persistence by so many people over a very, very long time.

- [Michelle] As the sun fully set, moths and other nocturnal insects started to emerge.

- There's a little leafhopper.

Oh, there's a little tubeworm moth, yep.

We are looking at a sheet with some UV lights on it to attract moths and other night-flying insects.

And then we are photographing them with a macro lens 'cause a lot of these guys are really tiny.

Even with a macro lens, just a photograph is not enough to be able to identify them a lot of times.

You really need to dissect them or even DNA barcoding.

Why UV lights?

Well, UV lights attract insects.

We're not totally sure why things come to lights like this, but they can also see different wavelengths than we can see.

- Look at this little moth.

- What is that?

- Is that a, what do we got?

Is it a beetle?

- I think it's a beetle.

- I think it is.

- It's a beetle, it's a large beetle.

One of the key tenets of conservation, particularly conservation these days when there are a lot of rapid land use changes, a lot of development, is that having just these isolated pockets of habitat doesn't really work.

It's great, but on its own, these places remain very, very vulnerable to lots of these human cause factors.

To increase their resiliency and also to make sure that animals can move between them, which is important for animal populations and animal diversity, it's important that these places are protected.

And that is what landscape connectivity or wildlife habitat connectivity is all about.

And wildlife corridors are a really critical part of that.

And so happens that where we are right now, the New Hope Creek Corridor is a particularly important one for this part of the state.

- [Michelle] Flashlights illuminated the woods around us, helping to spot everything from spiders to evidence of beetles snacking on trees, some nighttime predators.

- This is a mantis.

We have the native Carolina mantis and the invasive Chinese mantis.

You see it's doing its little defensive posture there.

It's pretty cool.

It's coming for me.

You can look at the shape of their head.

One is more squarish and one's more triangular like between the eyes.

I'm not a mantis person, so don't quote me on that.

They're such interesting creatures.

- [Michelle] And tiny herbivores.

- Oh, it's a little caterpillar.

- Yeah.

- These are the ones that are completely impossible to identify without.

- Amazing.

- He was on a waffle leaf.

- Okay, that's a start.

But the little green inchworms, you would definitely need to raise that one all the way to adulthood to find out what it was.

- [Michelle] Using a macro lens and a flash, David documented some of the moths lured in by the glow of the UV lights.

- Okay, anything I need to take a picture of.

- [Michelle] While there are 178 known species of butterfly in North Carolina, there are over 3,000 species of moths.

- Why am I excited about moths?

The diversity of them excites me.

We're finding new species all the time, new to the state and even new to science, especially with the little tiny micro moths.

They're really important ecologically.

They're sort of the foundation of a lot of our ecosystems, converting the plant biomass into a form that can be used by birds and other animals.

They're also a great indicator of the health of different habitats 'cause they're fairly easy to sample with traps.

And you can tell based on the diversity and the quantity of them, like how well the habitat's doing.

Like we did a big survey here at the bottom lands a few years ago.

And even though this area looks great, it looks like a really nice, healthy ecosystem, we didn't see nearly the moth diversity that we were expecting to find.

So that gives us an indication that something's going on here that's not good.

The more people that know about this stuff, the better.

The more people that are aware of it that can think about this stuff is they're getting to think about what they want their communities to look like long-term.

So there's a lot of benefits to having these big, fun public events like this.

- [Michelle] And if you wanna support more insect diversity in your backyard, start with looking at what you're planting.

- They generally don't like the non-native plants.

Like I was just telling somebody earlier that the crape myrtles or Bradford pears in my neighborhood, I've never found anything on those.

They're just, nothing's eating them at all.

So definitely native plants if you wanna support bug populations, definitely go with native plants.

♪ - [Michelle] If you enjoyed that story, there's more where that came from.

Hit subscribe to keep exploring with Sci NC and PBS North Carolina.