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Wait, we have fireflies in Florida?

Fireflies are indeed in Florida; you just have to know where to find them. Fireflies, also known as lightning bugs, avoid areas with high volumes of artificial lights and lots of urban development. In this episode of Naturally Florida, we’ll be discussing the lifecycle and conservation of fireflies in Florida.

Episode Transcript:

SHANNON:
Welcome to “Naturally Florida.” Thanks for joining us today. On today's episode, you'll be hearing all about Florida's fireflies. We have over 50 species in the state and most people have never seen one. Thanks for tuning in and we hope you enjoy the episode.

LARA:
Welcome to “Naturally Florida,” a podcast about Florida's natural areas and the wild things that live here. I'm Lara Milligan.

SHANNON:
And I'm Shannon Carnevale.

LARA:
This podcast is brought to you by UF/IFAS Extension in Polk and Pinellas Counties.

Shannon, I know on today's episode we're going to be talking all about fireflies, which is perfect timing because I just got back from a trip from North Carolina where I got to see a ton of fireflies in the mountains.

SHANNON:
Aah, how pretty!

LARA:
Yeah, it was beautiful. But I think it's going to be really interesting for our listeners to learn that we have fireflies right here in Florida.

SHANNON:
We do. We actually have quite a few. We have more species of fireflies than any other state. In Florida over 50 species.

LARA:
That's crazy. Yeah, I didn't honestly know we had fireflies in Florida until probably like a year into my job as a natural resources agent. So take that for what it is. (LAUGHS)

SHANNON:
I would say that's really very common. Most people have no idea that we still have fireflies in Florida unless they live in a very rural area or if they live adjacent to a swamp or lake. And even then they still need to be pretty rural. Otherwise they probably just don't even know we have them and think, like you, that you need to go to the mountains to see them.

LARA:
Right. Yeah. I mean, the only way I knew fireflies even before that trip was when I went to visit my grandparents up in New Jersey. That was like the childhood memories. Yes, we get to go catch some fireflies.

SHANNON:
Absolutely. I mean, when you think of the quintessential storybook Firefly Time, you're in an open meadow. There are mountains in the background. It's summer, and they're blinking all over the field. But it looks nothing like when we see fireflies in a lot of places in Florida.

LARA:
Yeah. So do you want to tell our listeners a little bit about why maybe we aren't seeing fireflies everywhere?

SHANNON:
Like other nighttime critters that are more common in rural areas, usually the culprit of the decline is lighting and development. So any time you have a lot of artificial light at nighttime, especially around dusk and sunset, you're going to have fewer fireflies. And just like with other wildlife critters and you have a lot of development, you might be disrupting their life cycle by getting rid of where their larva spend their time.

LARA:
Yeah. So I guess I have two follow-up questions based on that. So what is it about, you mentioned light pollution, why is that so negatively impacting to the fireflies?

SHANNON:
If you think about what fireflies are doing, they're blinking, right? Or they’re “flashing” is probably the more technical term. And what they're doing is communicating with each other and predators. So when you have artificial light there, by comparison their flashes are very, very dim. So if we have a lot of darkness, they can easily talk to each other.

But if there's ambient light, say, a patio light or even worse car headlights driving by, that will disrupt the pattern of their communication. So it would be just like you and I talking, but the microphone going out as we're trying to communicate, (LAUGHTER) we just wouldn't have any idea what the other person was saying.

LARA:
Yeah. I mean, I can read lips, you know, decently, but that would definitely present a challenge. So based on what you just said, so both the males and the females blink/flash.

SHANNON:
Yes, for the most part. And they have different flash patterns. So they don't all fly. When we think of fireflies, we think about them flying in right above the grasses or up in the shrubs, occasionally in trees, or they might be dancing little patterns. We have a species in the eastern U.S. called the Big Dipper that kind of makes a J shape when it's blinking.

So it'll flash and then it'll kind of rise up a few inches and create a J shape. But the males and the females, like you said, they're trying to communicate with each other. And the females more often than not are hanging out in the habitat, waiting for the males to come to them. So they're just trying to find each other for mating purposes.

So the female might glow or blink really slowly and it will alert the males, oh, there's a female there. And so they'll start blinking and try to find each other.

LARA:
Awesome. Yeah. And that kind of leads to the second question I was going to ask you about habitat loss. You mentioned, you know, they're trying to find each other to mate, but that, you know, habitat destruction is really negatively impacting them as well. And that has a lot to do with their life cycle, right?

SHANNON:
Yeah. When we think of fireflies, they're very ephemeral. They only show up for a week or two at a time. Sometimes in Florida you'll get like a spattering of fireflies throughout the summer or have two separate peaks, one in late spring, say, April, and then again in late summer in July and August. It depends on the weather that year.

But the habitat destruction often creates problems for them as a larva. So they might spend three weeks or four weeks as an egg, but then they'll spend the next year or two or more, depending on species, as a larva. And the larvae will live in the leaf litter and the deep grasses, and they are very predacious. So they're going to be hunting things like slugs and snails and other small things that are soft bodied, like an earthworm, for instance.

Yeah, it's really cool that they're predacious and they're tiny and they could be there for years. So a big threat to something that lives in leaf litter and under grasses is, of course, lawn mowing or land development. And the things that really threaten them, besides the obvious destruction of a mower, is after you go through there with equipment like that, it will be a lot drier after the fact.

So having a drier leaf litter will lead to less prey and that can cause a lot of problems for them. And after their couple of years as a larva, they turn into a pupa and then they become an adult. And that's the part we’re all excited about. So if you mess up the cycle at the larva stage, you're not going to get to the adults that we all want to see.

LARA:
Right. I guess talking about, you know, we've talked about we do have fireflies here in Florida. Some people might see them, some people might not. But if somebody is interested, maybe they're like, Okay, wow, we have them here in Florida. Where can people go to find them?”

SHANNON:
I would recommend people talk to their local astronomy club. That's a great way to find out where the dark areas are. You likely need to get out of town. So if you're in a city, you need to leave the city. You need to go to those backcountry roads and really look for areas that have water nearby because they need that moist leaf litter.

But if you can't find somewhere to go just by driving down the road and pulling off in a field, either because you don't know where to go or you don't feel comfortable doing that—a lot of people don't feel comfortable just pulling off on the side of the road.

LARA:
Right.

SHANNON:
It takes a special soul like ours (LAUGHTER) to go hang out in an empty field all night. But there's a lot of safe places you can go, like state parks. And once you find a good spot to look, it's important to think about when you're looking. So some of our species will only flash for 20 minutes in the evening, which is why those headlights can be a problem.

So if you have a species that only flashes for 20 minutes and a headlight of a car goes by, it might interrupt them for 10 minutes. They've lost half of their communication period. But once you figure out where to go, be flexible. You might have to go out there a couple of nights. You might have to try again in a couple of weeks after it's rained or something like that.

And that's why asking your local park rangers when the best time to go, that's a great idea. There are also firefly groups on social media, so you can try and get hooked into when a particular species is out and about.

LARA:
That's awesome. Yeah. We actually right here where my office is stationed at Brooker Creek Preserve in Tarpon Springs, we do have fireflies here. So that was my first exposure to fireflies in Florida. So even in a very urban area, you know, if there's pockets of natural area, like you said, they can be there, which is kind of a good segue to what I wanted to talk to you about next.

If people were interested in creating like an oasis for fireflies in their yard, what would people need to do?

SHANNON:
If you're in an area that you reasonably can suspect has fireflies or near an area that has fireflies, especially if you're near the rural side of the urban-rural spectrum, then I would say absolutely try. If you are on a property that has waterfront and, mind you, this doesn't need to be a huge lake, if you have a ditch that runs through your backyard, anything like that can be helpful to fireflies.

And what you'll need to do is consider planting some native vegetation. So you'll want some native grasses, leave it un-mown. And to the best of your ability, avoid using insecticides in that corner of the yard, or generalist pesticides in general. Anything to help protect that larva stage. And be patient. It could take several years because remember once the fireflies mate and they're looking for somewhere to lay eggs, it could still be three years or more until you actually see adult fireflies there.

We have some fireflies in my backyard very, very rarely. And it's usually only three or four at a time. And, you know, we talked about knowing when to look. Some of them only blink for 20 minutes. Some are right at dusk. These for whatever reason—I haven't figured out what species they are—but they will flash at like 10:30, 11:00 o’clock at night for like, I don't even know 5, 10 minutes maybe.

But perhaps they stop blinking because I get so excited and run out there. (LAUGHTER) So it's hard to say. If you don't live in an area where you think you have fireflies and you think creating a firefly oasis might be a waste of time, something you can do to help them is work with your city or municipality. If you've got some larger parks, ask them to turn the lights off in certain areas that are near water, even if it's just in the summer.

So find out what species might be near you. And I admit that's really hard to do. It's an emerging research area.

LARA:
Yes.

SHANNON:
But if you know you have fireflies and they're at a certain time of the year, maybe your parks department is willing to reduce the lighting near water during those times a year.

LARA:
So some people might have concerns about attracting fireflies here to their yard. Do you know if they bite?

SHANNON:
They don't bite.They only bite as larva, so when they're in their little caterpillar grub stage. And they eat a lot of garden pests, so they're actually a wonderful thing to have around. If you see them during the daytime while you're gardening, it's important to know what they look like so you don't accidentally squish them. This is definitely part of that good bug/bad bug educational outreach piece.

So fireflies actually aren't flies at all. They're beetles and they are usually less than an inch long. Most of them are half an inch to three quarters of an inch in our area. And they are beetles, so they have hard exterior wings and they tend to be dark in color with a little bit of orange around the edge of the wings. And where the head or shoulders might be, it's going to be a dark color with some orange or reddish coloration to the center of it as well.

LARA:
Yeah. I know for sure if you ever get the chance to see a firefly glowing, you know, it's always at night. And so when you actually get the opportunity to capture one or look at one up close, it's just, I don't know, it's kind of mind-blowing to me like what they actually look like. So yeah.

SHANNON:
Yeah. And we've taken people out on firefly walks before, and when the firefly actually lands on them, they swat at it because they look at it with a flashlight and they think it's a bug. Well, it is a bug, but it's an insect and it's a beetle. And that's the one you literally came out here to see. (LAUGHTER) Please don't squish them when they're not blinking. They might land on you if you're in an area with a lot of fireflies. And they're pretty quick, so try not to panic. But it just means you're not scary, and that's a good thing.

LARA:
Yeah. This has been so fascinating to learn all about fireflies. And I know you mentioned we have 56 species here. But it's impossible really to tell the species apart unless, I mean, you basically have to kill them is my understanding, or really have them in hand to identify. And we're just, that's not something we're going to advise.

SHANNON:
Yeah. Identifying fireflies to the species level is not something I would recommend our listeners get into unless you are already an entomology student. Because you're right, you often have to take them out of their environment to get a really, really good picture under a microscope. And it's just not practical for most people to try and identify to the species level.

But there are some very general things that I can tell our listeners that might help quell that need to know what you're looking at. (LAUGHTER) So in general, the most common firefly species that flash or blink are going to be your Photuris or Photinus. And that’s spelled with a “ph,” both of them. And your Photuris fireflies are going to blink more greenish yellow later in the evening. And your Photinus fireflies are going to blink more of a orangey yellow closer to dusk.

So if you have young eyes—and that's (LAUGHTER) typically referred to as 35 or less—the younger the better. If you have a pre-teen at home and they're like, “Oh, that one's yellowy,” listen to them (LAUGHTER) because their night vision is going to be better than in adults.

LARA:
Yeah. And I know you even showed me a book where there's like the different flashes. I think you mentioned this before, it can help you identify what species. But then there's also some species that try to mimic other species out there. So it's really impossible to… Not impossible, it’s very challenging to identify.

SHANNON:
It is. It's extremely challenging. So if you can identify it down to the the genus, that Photinus, Photuris. There are about three, four, maybe five others. I think you're doing pretty good. And you mentioned mimicry. And that's one of the other reasons it's really challenging to identify them. In the Photuris genus or genera they are also known as the “femme fatale.”

So in general, we were talking about how fireflies don't bite or sting as an adult because they're not trying to eat anything. But the Photuris femme fatales will eat. And so they will sit there and they will watch what the other female fireflies are doing that evening. And they'll mimic them and put out the same flash pattern to try and lure that other species male to them.

And then they eat him. And they eat him because fireflies have a lot of defensive chemicals running through them. And by eating that adult male, they can then transfer that protective chemical to their eggs and larva, helping them survive the next round of life cycle. So because they're like the mockingbird of of fireflies, so it's really hard to tell who's who.

LARA:
That's insane.

SHANNON:
Complicated world out there.

LARA:
So complicated. (LAUGHTER) It’s so cool. And like you said, just still so much unknown. And I think that's what's really fascinating. That kind of concludes the questions I had lined up for you, Shannon, but I was curious if there's anything maybe I failed to ask you or something else that you wanted to share with our listeners about fireflies.

SHANNON:
I would just encourage people to be excited about our Florida fireflies. They need all the help they can get, guys. We have a lot of people here. We have a lot of light at night. So turn off those porch lights. Give them a little section of your yard where you will stop mowing. And help protect that waterfront a little bit so that perhaps in the future we can have more of those firefly nights we all have come to love in storybooks and where they do have a lot more rural area.

LARA:
Great. Well, thank you so much. I have certainly enjoyed learning all about fireflies and I hope our listeners did too. And yeah, we look forward to catching up with y'all and our next episode.

SHANNON:
Thanks for listening to “Naturally Florida,” a podcast about Florida's natural areas and the wild things that live here. Stay updated on new episodes by subscribing on your favorite podcast platform. If you enjoyed today's episode, consider sharing it with a friend. “Naturally Florida” is produced by your hosts Shannon Carnevale

LARA:
And Lara Milligan.

SHANNON:
If you have questions or suggestions, submit them online at naturallyfloridapodcast.com. This podcast is brought to you by the University of Florida's Institute of Food and Agricultural Sciences Extension, an Equal Opportunity Institution. Thank you for listening.

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