The emergence of cicadas has begun in force across much of the Chicago area, but now that it has started, many are wondering: how long will it last?
That all depends on the life cycle of a cicada — and how long it takes for the final cicadas to begin their trek out from underground.
Plus, just when you think you might be done with the historic 2024 emergence of periodical cicadas, another cicada emergence is slated to begin.
Here’s what to know:
How long will cicadas last in Illinois?
Once they emerge from the ground, cicadas have a lifespan of approximately four weeks, meaning the emergence is set to last through at least mid-June.
When cicada nymphs first come out from the ground, they climb up to a tree or another high place and shed their shells.
“The nymphs typically emerge from the soil in the evening and climb up trees or other objects and molt, leaving behind the familiar cicada shells or shed exoskeleton,” the University of Illinois reported. “After the adults emerge, they are white and soft-bodied. They will darken and harden overnight.”
In a year of full emergence, after the bugs surface, they then begin mating, which is often met with the noise most associate with cicadas.
According to experts, when male cicadas sing their mating call, it attracts other males to that location to do the same.
Known as “the chorusing center” the loud mating calls then attract females to the screaming tree to fly in and mate.
According to Dr. Gene Kritsky with Mount St. Joseph University in Cincinnati, it takes five days for a cicada to begin singing after it springs from the ground.
The sound will slowly diminish as cicadas reach the end of their four-week lifespan.
Once they mate, the female periodical cicadas then lay their eggs in “new growth of woody plants,” the U of I reported.
“They prefer branches about the width of a pencil or a little larger, up to ½ to 1-inch in diameter. They will use their saw-like ovipositor, or egg-laying organ, to cut into branches and lay 10 to 20 eggs before moving further down the branch,” the university wrote. “Each female will lay around 500 to 600 eggs.”
Between six and 10 weeks after eggs are laid they begin to hatch and the newborn cicadas will fall to the ground, where they will eventually dig down into the soil and remain for the next 13 or 17 years.
See a video explanation of their life cycle below:
Watch as district staff put a creative twist on taking us through the fascinating life cycle of a 17-year cicada.
Next 2024 emergence
Beyond the periodical cicadas, there are also annual cicadas known as dog-day cicadas, which appear every year between July and September in Illinois.
Unlike the periodical cicadas, which are synchronized and emerge in mass amounts every 13 and 17 years, the dog-day cicadas emerge every two and five years and are not synchronized, so they often overlap.
“Once they emerge, they mate and lay eggs. The eggs hatch, and the nymphs feed on the sap in trees and shrub roots for two to five years,” the U of I reported.
What else to know
The periodical cicada emergence of 2024 is historic in that the 13- and 17-year cicadas are emerging together for the first time since 1803. This won’t happen again until 2245.
Sightings have been climbing in the Chicago area this week following several days of hot temperatures.
Warm weekend temperatures likely sparked an increase in the emergence in the Chicago area, as experts said the emergence would begin in force once ground temperatures reached 64 degrees.
A map that tracks cicada spottings across the U.S. shows some of the highest sightings have been reported in suburbs west of Chicago, particularly near the Downers Grove area.
“This is like the year for Illinois,” cicada expert Catherine Dana, an affiliate with the Illinois Natural History Survey, told NBC Chicago. “We are going to have cicadas emerging all over the state.”