Lightning Bugs Disappearing, Could Make MI Summer Nights Less Magical

MICHIGAN — Fireflies should be lighting up Michigan's back yards, fields, marshes and forests soon — or will they? Sometimes called lightning bugs or glow worms, fireflies are disappearing around the country and worldwide.

“And if it continues, fireflies may fade forever, leaving our summer nights a little darker and less magical,” warns Firefly Conservation & Research, a nonprofit founded in 2009 by firefly researcher Ben Pfeiffer after he noticed fireflies were disappearing from southern Texas.

There are about 170 species of these so-called jewels of the night in North America, and although populations vary by region, they’re found in every U.S. state except Hawaii, according to the Brandywine Conservancy.

Exactly when Michiganders can expect to see lightning bugs is hard to predict and depends in large part on the weather, according to the Farmers’ Almanac. Fireflies thrive in muggy weather. When those conditions arrive before June, the insects are fooled and make an early appearance on lawns, gardens and trees.

Firefly sightings have been Average in Michigan over the past five years, according to data curated by World Population Review, which consulted sources that include, among others, Brandywine Conservancy, Mass Audubon, cooperative extension services, Pennsylvania Wilds and the National Park Service.

Habitat loss to development, overuse of pesticides, climate change and increased light pollution are behind the declining firefly populations, though some species are more at risk than others, according to the Xerces Society for Invertebrate Conservation and the International Union for the Conservation of Nature Red List of threatened species. Of 128 species considered for the Red List, 11 percent are threatened with extinction and 2 percent are near threatened.

Here’s what you can do to help keep the magic in summer nights:

Turn The Lights Down Low

Actually, to set the mood for fireflies, turn off porch lights and other outdoor lighting entirely. Scientists are still learning about firefly behavior, but it appears likely artificial lighting can disrupt fireflies’ flashes, which help them find mates and breed. Improve their chances by drawing blinds and curtains, so interior light doesn’t intrude on your yard.

Because fireflies thrive in standing water and marshy areas, create a water feature in your landscaping. Even a small pond or stream will attract fireflies.

Create Firefly Habitat

Gardens are ideal habitat for fireflies — especially the “big dipper” firefly (Photinus pyralis), which feeds off organic matter. Fireflies spend 95 percent of their lives as larvae and feed off snails, slugs and other insects that gardeners find troublesome.

To create ideal habitat, plant trees and native grasses, and consider leaving some of the leaf litter to give firefly larvae a place to grow. To more proactively promote firefly promotions, consider a more aggressive plan to create firefly habitat.

Avoid chemical pesticides and weed killers. Studies suggest that lawn chemicals are toxic to lawns where firefly larvae are found and to the food they depend on to survive. Using natural fertilizers may make the lawn a healthier place for fireflies.

Also, don’t over-mow your lawn. Fireflies remain on the ground during the day, and frequent mowing may disturb them. To strike a balance between keeping the lawn cut for aesthetic purposes and encouraging firefly populations, consider landscaping that uses tall grasses, where fireflies prefer to live. Also consider planting native tree species.

Individuals can make a difference, but the greater power is in organizing a community-wide effort to allow a little wildness to prevail on their properties, according to Firefly Conservation & Research.

If You See Something, Say Something

Pfeiffer’s organization also recommends submitting sightings of fireflies to iNaturalist, which has apps at the App Store for iPhone users or Google Play for Android users. Firefly light organs are on the underside (ventral) of the firefly.

If possible, document the flash pattern — the interval of flashes per second — as well as the color of the flash, the date and time of night, the geographic location where the firefly was seen, and the type of habitat where the fireflies were seen.