Fireflies have always lit up the Chicago area’s backyards, but have been harder to spot over the last few years.
That’s changing.
The small bugs seem to be thriving this season, thanks to a mild winter and wet spring.
“It seems that this is a pretty good year for fireflies,” says Allen Lawrance, curator of entomology at the Peggy Notebaert Nature Museum.
He and his colleagues have seen a lot of fireflies this summer.
The firefly population usually peaks in late June or early July. But the firefly has been struggling over the last few years for several reasons, Lawrance says. He blames everything from loss of habitat, increasing light pollution, climate change and pesticide use.
Extreme weather, such as high heat and droughts, can make it difficult for bug larvae to survive.
Because there is no hard data on the exact number of fireflies each year, Lawrance said, it’s difficult to tell just how much the bugs’ populations have grown.
Tom Tiddens, supervisor of plant healthcare at the Chicago Botanic Garden, said that he hasn’t noticed a large decline in firefly populations. But he had noticed an uptick in the amount of lightning bugs in his own backyard last weekend when he sparked a bonfire with his wife.
“Just as it started to get dark, I saw more fireflies than I’ve ever seen in my backyard,” he said. “I think they were just starting to emerge. I literally tried to get pictures of it, because it was just so beautiful. I was looking across my backyard, and I was seeing hundreds of fireflies, it was pretty cool.”
Tiddens said while there are 2,000 different types of fireflies around the world, the common eastern firefly is the one most people are used to seeing. They are nicknamed the big dipper, because of the flight patterns of the males, who fly in a j-shape and light up on the upswing.
Spencer Campbell, a plant clinic manager at the Morton Arboretum, said the bioluminescence of the fireflies — the way they’re able to project their bright green lights in order to attract mates — is uncommon and only found in select species.
“It’s a rare display in the natural world,” he said.
“They’re so charismatic, and humans really take to them,” said Kacie Athey, an assistant professor, entomologist and extension specialist at the University of Illinois Urbana Champaign. “I think of fireflies and large butterflies as a gateway drug to people being less entomophobic [meaning fearful of insects], because it’s hard to be scared of them. They’re amazing.”
To help protect fireflies, Lawrance suggests that people allow dandelions and other wild plants to grow on their lawn, limit outside lights at night, avoid pesticides and to contribute to monitoring and tracking firefly populations through mediums like the Firefly Atlas.
“It’s important to conserve insects in general, because they fit into so many different ecological niches and are just incredibly biodiverse,” Lawrance said. “Fireflies are just one of those pieces there.”