When Do Lightning Bugs Come Out? (With Map)

A firefly rests on a blade of grass

You might here these insects called lightning bugs or fireflies, but they are actually beetles (photo by Suzanne Tucker/shutterstock.com)

Lightning bugs are just about everywhere in the United States. However, they are usually much more difficult to detect in some areas. According to the Smithsonian, males flash when they’re in flight to attract females among the Eastern species. However, out West, it’s the females that glow. However, the females glow more faintly and on the ground.

What months are fireflies most active?

For most of the United States, including the Great Smoky Mountains area, the lightning bug season is May to August. In the extreme southern U.S. and Hawaii, the extended season runs from May to November. Overall, they like moist areas and warm summer nights. The best times to see an adult firefly would be in the middle of the mating season when the nocturnal insects – we’ll get back to that later – are in the midst of hunting for potential mates. So generally speaking, it’s June and July when the fireflies are mating that you see the most of them.

But it’s somewhat deceptive to think that the beetles are more active in these months. The firefly’s lifespan is only a couple of months, and so you’re seeing generations over the course of the summer. They’re not the most active in June and July, necessarily, that’s just the time of year when they’re the most prominent. If you want to catch the light show, late June and early July are your best bets. That being said, there is a species of North American firefly that thrives through winter. However, they hide in the bark of trees so you’re unlikely to come across one. Even if you did find one, the adults don’t light up.

Super macro close up firefly
Here’s a fun fact that’s bound to impress your friends: Lightning bugs aren’t actually bugs – they are beetles (photo by khlungcenter/shutterstock.com)

Synchronous Fireflies in the Smokies

Ok. But the Smokies have fireflies, right? Of course. But it’s also worth noting that they’re more likely to be called lightning bugs. The Smokies also have what are likely the most famous lightning bugs in the world per the National Park Service. Synchronous fireflies (Photinus carolinus) are one of at least 19 species of fireflies that live in Great Smoky Mountains National Park. But they are one of only a couple species in North America known to synchronize their light patterns.

a map of the united states shows that lightning bugs enjoy an extended season in tropical climates
In temperate and subtropical climates, lightning bug/firefly season runs from May-August. In tropical climates (in the southern United States) lightning bug season may extend to early November. However, their numbers are generally greater in June and July (infographic by Morgan Overholt/TheSmokies.com)

Do lightning bugs only come out at night?

The answer isn’t as simple as you might think. Where I’ve lived, fireflies have always been from dusk to midnight or so. I can’t ever recall seeing lightning bugs flashing away in the wee am hours or pre-dawn. However, it may depend on the species of firefly or where they live. There are species of diurnal lightning bugs, but they only glow in the larval stage.

Traditional fireflies are also out during daylight hours, but the males of most North American species are usually hiding in the long grass, waiting to come out during warm summer evenings to attract female fireflies with their pulsating flashes of light. It turns out there are a whole bunch of species of lightning bugs. If you see them in your yard or elsewhere, you’re likely seeing different species. Interestingly, there is a female firefly of the Lamprigera group that can be as large as the palm of your hand. Their male counterparts are smaller and have no wings.

a firefly on a blade of grass
Fireflies are most active at night (photo by anko70/shutterstock.com)

How long do lightning bugs stay out?

It’s a good question. We’re going to speak in generalities for North America here. Some species will call for hours, others flash for only 20 minutes or so at dusk.

Are lightning bugs beetles?

Not technically. They are a type of beetle, although I would submit, by the common understanding of the term, they are bugs.

Are there any more lightning bug facts we should know?

For starters, did you know that there are femme fatales fireflies that lure males of other species to their end and steal prey from spider webs – a practice called kleptoparasitism? The female firefly is hardcore. And while they’re certainly not endangered, the various species of fireflies do face challenges from light pollution. Artificial light can wreak havoc on firefly season and cause habitat loss and or habitat destruction. At this point, firefly conservation is a real thing.

Do you enjoy watching the lightning bugs? Tell us what you think in the comments!


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1 thought on “When Do Lightning Bugs Come Out? (With Map)”

  1. I have lightning bugs in my yard, and I never put pesticides on my lawn bc I really enjoy watching them! I am trying to figure out how many different species I have though. I know it’s at least 3 bc I have ones that only flash for a short time, ones that flash in the trees all night, and in late July I get treated to ones that fly in the morning!! We’re talking 4:30-5 am. I work in health care so I’m up that early and during the hottest most humid nights I see fireflies in the morning. Any ideas on what species I’m seeing?


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