If you’ve noticed an increase in the number of dragonflies in the Chicago area this summer you’re not alone.
Chicagoans visiting the city’s lakefront have likely spotted large swarms of dragonflies flying around the lakefront and officials say the sight is not a common one for this time of year.
“There have been just an absolute ton of green darner dragonflies in the region for about the last week,” said Doug Taron, curator of biology at the Peggy Notebaert Nature Museum. “They’ve shown up in large numbers and a lot of people are seeing them in feeding swarms where there are dozens or maybe hundreds of them whirling around each other flying.”
The dragonfly swarms are actually seen when the insects are feeding or hunting smaller insects like mosquitoes and gnats.
Taron says that while the green darner dragonflies aren’t uncommon in the area, these “feeding swarms” aren’t typically seen until the fall months. The large numbers of dragonflies have been reported all over the Chicago area and in northern Indiana and Wisconsin.
Taron noted there is speculation that the unusually early sightings could be caused by the large number of mosquitoes the area has seen this year.
“With all of those mosquitoes there was a big food supply for the dragonflies and so it’s possible that a lot more of them successfully became adults,” Taron said.
It’s not clear how long the dragonflies will stay in the area.
Taron noted the feeding swarms are often associated with migration, but because they’ve appeared so early, officials aren’t quite sure if they’ll leave as quickly as they came.
“It’s possible that we’ll see a rapid decrease in the numbers, but we don’t really know that,” he said.
But if you get caught in one of these swarms, Taron said you shouldn’t worry.
“They’re not going to hurt you,” he said. “It can be a little alarming to be in one of these huge swarms of fairly large insects flying all around you but they don’t bite, they don’t sting, they’re not going to attack you and they’re really good for the environment...they're actually very beautiful.”