Get ready. Trillions of chirpy, red-eyed periodical cicadas are getting ready to emerge from underground in a rare double emergence event. These specific types of cicadas crawl out from below the ground every 13 or 17 years and can make as much noise as a jet engine.
While there are 3,400 known species of cicadas, only nine of them have the tendency to disappear underground then reemerge all at the same time. Seven of these nine periodical cicada spears are found in the United States. Even though it is not happening all across North America, it is still a huge natural event that’s worth keeping an eye on.
“I would put the periodical cicadas as a natural phenomenon in the same category as April’s total solar eclipse,” Penn State University entomologist Michael Skvarla tells PopSci.
What is a brood of cicadas?
A brood is another term for a group of periodical cicadas that emerge every 13 or 17 years. Scientists use roman numerals to differentiate between various broods in North America. This year, Brood XIII (aka the Northern Illinois Brood) and Brood XIX (the Great Southern Brood) will emerge at the same time.
The Northern Illinois Brood is a 17 year group and stretches across parts of Indiana, Wisconsin, Iowa, and northern Illinois. The Great Southern Brood emerges every 13 years and is primarily located in Arkansas, Missouri, Tennessee, Alabama, George, North Carolina, South Carolina, and importantly, southern Illinois.
[Related: Cicadas pee in jet streams like bigger animals.]
“This year is kind of special because we have the emergence of two broods,” says Skvarla. “ We have one 13 year brood and one 17 year brood emerging. Because they’re coming out every 13 or 17 years, they don’t sync up very frequently.”
When will they emerge?
They will start to emerge as soon as the surrounding soil has reached 64 degrees Fahrenheit. That usually occurs anytime between late April and June and the cicadas will…
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