Subscribe | UPI Odd Newsletter Subscribe May 4 (UPI) -- Chicago residents have reported an unusually large swarm of gnats overtaking the city, but experts said its a natural phenomenon and nothing to be worried about. Chicagoans have reported on social media that they have been encountering more gnats than is usual for this time of year while outdoors in recent days. Advertisement The insects, also known as chironomid midges and non-biting flies, are common in the region during the springtime, but experts said this year's population is unusually large. "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." Lawrence said researchers are not yet sure what caused this year's large swarm, but populations can be affected by factors including weather and viruses, as well as the presence of predators such as fish, dragonflies and migratory birds. He said the large swarm is unlikely to last long, as gnats typically live for only 3-11 days. Advertisement "You will never have them completely go away," he said. "But we should get past this huge swarm at some point pretty soon here." Read More Texas dog dubbed world's tallest at 3 feet, 5.18 inches Traveler reunited with lost taxidermy rat after nearly a year Florida woman goes skydiving for her 100th birthday
