Summer nights are lit this year with a good firefly crop
Add Axios as your preferred source to
see more of our stories on Google.
/2025/07/01/1751379998055.gif?w=3840)
Illustration: Brendan Lynch/Axios
You're not imagining it. Fireflies are having a good year.
The big picture: In general, firefly populations have declined over the last 100 years, said Megan Abraham, division director and state entomologist at the Indiana Department of Natural Resources.
- Yes, but: Conditions were good for fireflies this year, and there are likely more of them lighting up night skies near you than in recent summers.
What she's saying: "Every once in a while, we'll see a resurgence because of perfect weather conditions and there will be fireflies all over and that's what we're seeing this year," Abraham said.
How they work: Fireflies lay their eggs in moist soil and leaf litter.
- They emerge in the spring and early summer.
- Once they reach adulthood later in the summer, their sole focus is to reproduce and then, after a couple of weeks to months (depending on the species), they die.
Threat level: A late freeze can kill larvae after they've emerged, but a hot, dry spring can dry them up.
- "We had a mild, moist spring, and they had a really good larval stage," Abraham said.
Zoom out: Much of the country had a warmer, wetter spring than usual.
Fun facts: There are more than 2,000 species of fireflies, and they produce light in different ways.
- The Say's firefly, named for Hoosier entomologist Thomas Say, is the state insect.
- Also known as lightning bugs in much of the Midwest and eastern U.S., fireflies are neither bugs nor flies. They're beetles.
State of play: Like many animals, fireflies have been impacted by humans.
- Light pollution confuses the mating process, making it harder for mating fireflies to see the blinking pattern that attracts them to each other.
- We've also encroached on their habitats. Pesticide use in home yards and on farms has decimated insect populations beyond those targeted by the chemicals.
How to help: Here are a few ways to support the firefly population and encourage more to light up your neighborhood.
- Plant a pollinator-friendly garden.
- Reduce light pollution.
- Cut back on insecticide usage.
- "Firefly larvae eat snails, slugs and small caterpillars," said Emily Justus, outreach coordinator at Purdue University's entomology department. "Protecting habitats that support those populations could help you with your fireflies."
The bottom line: "Everybody loves them," Justus said. "I think it's the lighting up at night and their association with summer — it being warm outside and fireflies are glowing. It creates such an ambience."