gnats chicago

‘Unusually Large' Swarm of Gnats Arrive in Chicago for Spring 2022. What to Know

Social media has erupted in recent days with people noticing the influx of the bugs known as "chironomid midges," or "non-biting flies"

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Wondering what's going on with the massive swarm of gnats in the city lately? You're not alone.

Many in Chicago have noticed a large population of gnats arriving this spring and while that may not be uncommon, this year's swarm is "unusually large," experts say.

Social media has erupted in recent days with people noticing the influx of the bugs known as "chironomid midges," or "non-biting flies."

"This is a natural phenomenon," Allen Lawrance, associate curator of entomology at the Peggy Notebaert Nature Museum, told NBC Chicago. "We'll see big emergences of them from time to time, but this year, we're definitely seeing a lot of them so it is a little bit unusually large, but it's not the end of the world times or anything like that."

The larger populations are being reported along Lake Michigan, Lawrance said.

Lawrance said the specific reason behind the larger-than-normal swarm this year remains unknown but the population can be impacted by weather, viruses and predators like fish and dragonflies.

The good news, according to Lawrance, is that the city is "in the peak of these swarms," but it will likely be short-lived. There is one caveat, however.

"The adults live for anywhere from three to 11 days," he said. "That varies based on temperature and whether... the cooler it is the more that's going to slow down their metabolism so they live a little bit longer."

"They will live a little bit longer if they're able to get their mouths on some food," he added. "They like to drink nectar, other sugary liquids."

So while it has been unseasonably cold in the city in recent days, Lawrance predicts the swarms will likely slow down by the end of next week, though various species are expected throughout the entire season.

"You will never have them completely go away," he said. "But we should get past this huge swarm at some point pretty soon here."

But while the flies are "kind of a nuisance," they are also "harmless" and actually play an important role this time of year," Lawrance said.

The insects not only attract migrating birds looking for food, they also serve as food for dragonflies and fish.

"They're just kind of awesome," Lawrance said. "They're used as model organisms for laboratory studies so they can help us study pollution, toxicology, diseases, climate and genetics. And they also are really resilient. They're a species that occur on every continent, including Antarctica, and they've even seen some species that fly out in the winter, so that's pretty unusual for insects."

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