17-Year Cicadas Are Now Swarming Across the Chicago Area

While driving into Chicago to visit family over Father's Day weekend, are car was repeatedly pelted by a barrage of flying insects. We quickly discovered our wipers were no match for the bug guts splattered across the windshield. Then we noticed a loud, piercing noise coming from outside. My son covered his ears and told us to close the windows. At that point my husband cried out "It must be the 17-year locusts."

We parked the car outside my father's home in a southern Chicago suburb near a wooded area. Although the noise wasn't nearly as deafening as earlier, it was still quite noticeable. My father came outside hugged us and asked, "So how do you like our cicadas?"

Minnesota is far enough away that we were completely caught off guard when we arrived in Chicago. This surprise encounter with the 17-year cicadas has left me curious about this infestation. The reporter in me felt compelled to research this natural phenomenon thus resulting in the Q and A listed below.

Are they 17-year cicadas or locusts?
Turns out people have used both terms to describe this onslaught; however, the correct term is cicada. Early North American settlers first referred to it as a locust attack because it reminded them of the locust plague mentioned in the Old Testament. The word locust more accurately describes a swarm of grasshoppers; a cicada is actually a leafhopper.

Where do the 17-Year cicadas come from?
All cicadas, including the 17-year cicadas (also referred to as periodical cicadas) actually hatch and live underground. They surface to mate then lay eggs on trees and die shortly thereafter. When the eggs hatch, they find a hole in the ground where they remain for 17 years.

How are the 17-year cicadas different for other cicadas?
The biggest difference is the lifespan. Annual cicadas live underground for only a few years and surface in much smaller groups. Periodical cicadas consist of three different cicada species emerging together to surface as a massive group in either 13 or 17 year cycles. Periodical cicadas are classified in groups called broods. The group blanketing central and northern Illinois is Brood XIII.

How do the 17-year cicadas make that sound?
For starters, the sound is a mating song made only by the male cicada to attract the female cicada. The male cicada has a pair of membranes that vibrate to create their song. The shrill can reach a level of 90 decibels. Also, different groups choose to sing at different times of day.

How long does the attack of the 17-year cicadas last?
The attack begins in late May or early June. Then the adult cicadas live on average 30 days. The cicadas are not dangerous to people; cicadas can however, cause some damage to trees.

This unexpected bug attack will be something my family will certainly remember each time we return to Chicago. Maybe to commemorate the occasion I should get my six year old son a special t-shirt that says "I Survived the Attack of the 17-year Cicadas of 2007." It's not a bad idea considering the next time he sees them he'll be 23 years old.