If summer nights seem a little brighter in Michigan this year, you’re not imagining it.
Favorable weather conditions in recent years have led to an explosion of firefly activity.
Researchers say fireflies thrive in climates that are warm and wet, and conditions in Michigan over the past year match that description – with the results shimmering every evening at dusk.
Jamie Sparks is a bicyclist in the Lansing area. He says going on bike rides in the evening this year almost feels like he’s making the jump to hyperspace in a Star Wars movie.
“When they are out, they’re out en masse, and they’re out around you, so I kind of just see them like stars in space, especially in the nighttime,” Sparks said.
For many in Michigan, watching – and possibly even catching – fireflies is a core childhood memory.
Sparks says he remembers catching fireflies in a jar to use as a lantern in forts he would build with other kids.
But while this year has offered a spectacular showing from fireflies, we may not always be so lucky.
Nathaniel Walton is a consumer horticulture educator for the Michigan State University Extension in Leelanau County.
He says fireflies have a two-year lifecycle, most of which is spent near the ground as larvae before they emerge for an adult lifecycle that lasts just a few weeks.
If conditions take a turn for the worse at any point during those two years, like an unusually dry late summer or early fall, it could have devastating effects.
“We can’t necessarily count on them being good again this year just because they were good last year,” Walton said.
Fireflies also face various other threats to their population, including habitat loss, pesticide use and light pollution, according to Richard Joyce, an endangered species conservation biologist with the Xerces Society.
While he says fireflies are an important part of the ecosystem and losing them would have an economic and environmental impact, he says the loss is also cultural and aesthetic.
“Maybe we experienced fireflies at our grandparents’ house, and, you know, I’m in my 30s and I would love as a grandparent to be able to, you know, decades in the future, to be able to share that experience with my grandkids,” Joyce said.
Joyce says it’s difficult to measure firefly populations year-to-year because there is no regular systematic data collection, with researchers largely relying on crowdsourced observations through platforms like Firefly Atlas, a project of the Xerces Society.
Crowdsourcing can be difficult, because while Michigan is home to 24 different types of fireflies, only 17 of them produce a visible glow at night to attract mates and ward off predators.
Walton says there’s a common feeling that we don’t usually see as many fireflies as we used to.
“A lot of people were kind of wondering what happened to the fireflies for many years. I know those of us who were younger in the 80s and 90s remember seeing a lot of fireflies in their yard in Michigan and then, you know, not as many,” Walton said.
That rings true for Lansing resident Heidi Schaetzl. She bought a house in the winter and says she was looking forward to curating native plants in her garden to help pollinators like butterflies, bees and fireflies.
She says her gardening has already paid off, with her backyard full of fireflies dancing through the night.
“I think the community has really tried to bring them back, and seeing everyone in all, like in my friend group, in different spaces online, saying, look at the fireflies, go outside, spend time in nature and just watch something from our past come back has been very rewarding,” Schaetzl said.
Other ways people can help protect firefly populations include minimizing pesticide use and unnecessary outdoor lighting, as well as by allowing some areas of their residential landscape to be a bit more wild with tall grass in the summer and fallen leaves in autumn.