As a child, Tom Tiddens knew summer had begun when he started to see fireflies in his backyard. One night, his father taught him how to mimic the bug’s signal to attract them. Tiddens recalls lying low in the grass and using his flashlight to imitate their blinking pattern.
“I’ve always watched and played with fireflies, but to actually sit there and attract one to the point that it came and landed on my hand, that’s something that kind of really stands out in my memory as being really, really cool,” Tiddens said.
Now, Tiddens is the supervisor of plant health care at the Chicago Botanic Garden, where he works closely with fireflies. This year, Tiddens and many others throughout the Midwest region have noticed higher numbers of the blinking beetles.
But this year is an anomaly, likely due to wetter and warmer weather conditions, Tiddens said. In reality, firefly numbers are believed to be trending downwards, and anecdotal reports say they have been for years.
According to Candace Fallon, a conservation biologist and firefly program lead at the Xerces Society for Invertebrate Conservation, about 18 firefly species are currently threatened with extinction, and two species are near threatened.
An even more concerning statistic, Fallon said, is that for more than half of firefly species, there is not enough data to properly assess the state of their population.
“It’s really those long-term data sets that we’re looking for to say, this is a trend,” Fallon said. “This is what’s happening over time. Unfortunately, in the U.S., we just don’t have those data to really inform the trends, like we don’t have baseline data on population sizes. This is something that we’re hoping to change.”
After realizing how little information was known about certain firefly species, the Xerces Society created the Firefly Atlas in partnership with the International Union for Conservation of Nature and the New Mexico BioPark Society.
Launched in 2022, Firefly Atlas is a community science program that looks to fill data gaps about fireflies by collecting and compiling firefly distribution data. It also serves as a resource for people to learn more about fireflies, including threats to their populations and conservation practices.
One of the biggest threats fireflies are facing is light pollution, which affects the bioluminescent light they use to communicate with one another, according to Emily Althoff, urban entomology specialist and assistant extension professor at the University of Missouri and Lincoln University.
“If you think about it, if you are a tiny firefly trying to find another firefly by shining your light, you’re going to get pretty distracted if there’s a huge light on the road or in someone’s house,” Althoff said.
To mitigate the decline, researchers suggest limiting the use of outdoor lights as much as possible. They also encourage people to leave some portions of their yard wild, which can serve as an important habitat for fireflies in their larval stage.
“That’s the biggest part of their life cycle,” Althoff said. “Their time as an adult is relatively brief compared to the rest of their life, and during [the larval stage], they like to be under the leaf litter, and so when we remove that, we actually are impacting their habitat.”
Spencer Campbell, plant clinic manager at the Morton Arboretum, said it is important to protect fireflies because they play a vital role in our ecosystem by managing pests, pollinating native plants and serving as food for a wide range of wildlife. And beyond their usefulness, they’re just cool.
“[Bioluminescence is] a unique natural wonder,” Campbell said. “It really delights people, and it’s a great way to tap into the magic of nature. We want to find ways to have folks develop and foster a deeper connection with nature.”
Researchers hope the awe and nostalgia brought on by these bugs will encourage people to do what they can to protect them.
As Fallon put it, “it’s impossible to see fireflies and not feel something.”
