After weeks of listening to the near-constant noise of periodical cicadas, which have popped up in about 20 states this year, you may soon hear a much quieter sound.
Some of the earliest emerging periodical cicadas are completing their life cycles and beginning to die after 13 to 17 years underground and a few weeks above ground. The 13-year XIXth generation in the Southeast and the 17-year XIIIth generation in the Midwest are unusual in that two generations have not emerged at the same time since 1803.
If you live in any of the roughly 17 states where either larvae have been spotted (or both, if you live in Illinois or Iowa), the season in which cicadas eat, mate, lay eggs and die may be coming to an end.
Here’s what’s expected as to when the 19th and 13th generation cicadas will start to die off.
‘One in a million’:Two blue-eyed cicadas have been spotted in Illinois, with two swarms swarming the state
When will the 19th and 13th generation cicadas start to go extinct?
Gene Kritsky, a cicada expert and professor in the biology department at Mount Saint Joseph University in Cincinnati, Ohio, said the 19th generation of cicadas, which emerged in mid-April, is already declining.
Kritsky previously told USA Today that Cicada Safari, a cicada-tracking app developed by Mount Saint Joseph University, first spotted adult cicadas in parts of Georgia, Tennessee and Alabama on April 14. The following week, they were spotted in North and South Carolina.
The central Illinois 13th generation cicada population is expected to decline in about three weeks, and in Chicago in about four weeks, Kritsky said.
How long do cicadas stay above ground?
The lifespan of a cicada depends on the number of offspring it produces and whether it is an annual or periodical species.
The two regular breeding flocks this summer are flock 19, which has a 13 year life cycle, and flock 13, which has a 17 year life cycle.
After male and female periodical cicadas mate and the female lays eggs, the insects spend a few weeks above ground before dying — three to six weeks after they first emerge.
This means that many of this year’s periodical cicadas will die in June, but depending on when they emerge, some may already be dead in late May and some may survive until early July.
According to the Missouri Department of Conservation, annual cicada larvae remain underground for two to five years. These species are called “annual cicadas” because some emerge as adults every year.
What is the Life Cycle of a Cicada?
A cicada’s life cycle begins with mating: Females lay eggs in holes they drill into tree branches or shrubs, according to National Geographic. The eggs hatch after six to 10 weeks, and the cicada larvae burrow into the ground and attach themselves to tree roots.
According to National Geographic, cicadas burrow underground for a “dormant period” that lasts anywhere from two to 17 years, depending on the species, before emerging as adults.
Cicada map for 2024: Where to find the 13th and 19th cicada swarms this year
The two cicada swarms are predicted to emerge in 17 states across the South and Midwest. The cicada swarms emerge when the soil 8 inches below the ground reaches 64 degrees Fahrenheit. The phenomenon begins in April and May in many states and continues into late June.
The last time the two races appeared together was in 1803, when Thomas Jefferson was president.
