Cicadas have made a return in the Chicago area and throughout Illinois, with these intriguing insects emerging from the soil. Trillions of periodical cicadas are surfacing this year, marking their first appearance in 17 years. While some find this spectacle fascinating, others may find it unsettling.
Illinois experiences both annual and periodical cicadas. The annual cicadas appear every year, while the periodical cicadas emerge in large numbers every 13 or 17 years. This year, the periodical cicadas are the focus. They have spent 17 years underground, feeding on tree roots, and have now emerged.
Why are there so many cicadas in Illinois?
The Insect Asylum notes that increased humidity levels can influence cicada emergence in Illinois. As the humidity rises, sightings are likely to increase. The insects typically start emerging when the soil warms, which occurs around late May or early June.
How long do cicadas live?
According to National Geographic, cicada lifespans vary, with over 3,000 species in existence. After mating and laying eggs, the eggs hatch about six weeks later. The babies fall to the ground and burrow into the soil, where they live for 13 or 17 years. The parents, however, die shortly after mating.
Are cicadas bad to have in your yard, and are they harmful?
Cicadas are generally not harmful, so having them in your yard is not a significant issue. They feed solely on plants and trees, do not bite or sting humans, and do not transmit diseases. However, their loud noise can be a disturbance in some cases.
Why are cicadas so loud?
Cicadas make their loud sounds with a corrugated exoskeletal structure in the thorax called a tymbal, according to Daily Science. The tymbal is an organ meant to produce sound.
According to Derke Hughes of the Naval Undersea Warfare Center, if a human body were like a cicada’s body, it “would have a thick set of muscles on either side of your torso that would allow you to cave in your chest so far that all your ribs would buckle inward one at a time into a deformed position. Releasing the muscle would allow your ribs to snap back to their regular shape, and then pulling the muscle again would repeat this.”
Extension entomologist P.J. Liesch of the University of Wisconsin-Madison told CBS 58 in Milwaukee that several singing cicadas in a grove of trees could reach 70 to 80 decibels – almost as loud as a vacuum cleaner.