ACROSS AMERICA — “Cicada-geddon,” as one expert called the upcoming emergence of trillions of periodical cicadas, could bring a wave of cicada tourism in the next several weeks to states where the noisy, red-eyed bugs will tunnel up from their underground homes, go forth and multiply and die in a few weeks.

This year’s crop of cicadas is expected to be so large because two broods of cicadas with different life cycles will emerge, likely starting in late April and continuing through June: Brood XIII, known as the Northern Illinois Brood, which has a 17-year-life cycle, and Brood XIX, the Great Southern Brood of 13-year cicadas.

An overlap of two broods hasn’t occurred since 1803. Even more cicadas will emerge in 2076, a veritable “cicada-palooza” with the dual emergence of the two largest broods, University of Connecticut cicada expert John Cooley told CBS News. But this year’s “cicada-geddon” will still be impressive, Cooley said.

Overall, there are 15 broods of periodical cicadas, three that spend 13 years underground and a dozen 17-year cicadas. Because of that, it’s possible to find periodical cicadas almost any year by traveling to the right location, according to a University of Connecticut research page.

Where To See Cicadas

The synchronized cicada emergence is an evolutionary marvel and worth the trip for people who groove on these kinds of things.

Someone claiming on an iNaturalist forum to be “cicada curious” is planning a road trip to Springfield, Illinois, to see and hear both broods as the insects worm their way out of the ground.

This is quite a year for Illinois, one of the states in the path of totality in the April 8 solar eclipse. The Land of Lincoln can rightly be called “cicada central.” Illinois and neighboring Iowa are the only states among 15 with periodical cicadas from both broods coming out of the ground, according to Cicada Safari, a resource site created by Gene Kritsky and the Center for IT Engagement at Mount St. Joseph University in Cincinnati.

Along with northern Illinois, eastern Wisconsin, eastern Iowa and northwest Indiana will also see Brood XIII bugs. Chicago is the only big city that will see the Brood XIII emergence and the Lake County Forest Preserve in Libertyville is a good place to see them, according to the site Cicada Mania.

Brood XIX cicadas emerge in central and southern Illinois, most of Missouri, and scattered areas of Kentucky, Tennessee, Virginia, Maryland, North Carolina, South Carolina, Georgia, Alabama, Mississippi, Louisiana and Arkansas.

Cities in the Brood XIX range include Nashville, Tennessee; Charlotte, North Carolina; and St. Louis, Missouri, “keeping in mind that they prefer the suburbs,” Cicada Mania said.

Cicada tourists should be aware the bugs prefer the suburbs and rural areas to big cities, according to cicada experts. But that certainly doesn’t mean cities will be cicada-free.

When To See Cicadas

Knowing exactly when to travel is tricky. When soil temperatures reach about 64 degrees, periodical cicadas begin making their way to the surface, mostly emerging at night to avoid predators. That means cicadas might emerge as early as April in southern states, but perhaps not until June in the Midwest.

Once they’re above ground, cicadas live for only about six weeks in whirlwind of mating and laying eggs until they die.

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Why They’re So Interesting

Scientists can’t fully explain periodic cicadas’ evolutionary strategy. One theory is their periodic emergence is timed to avoid certain predators. Tulane University biologist Keith Clay calls the emergence of periodical cicadas “one of the most unusual biological phenomena on Earth.”

One theory is that cicadas, which are lousy flyers and a veritable fast-food buffet for predators like copperheads, have adapted to ensure they don’t all get eaten up. Even if predators have a feast, there are so many of them that enough survive to mate and lay eggs.

If these evolutionary superstars of the bug world came out every 16 years, for example, predators with two-, four- and eight-year cycles would be around at the same time of year to eat them, according to Clay.

Another hypothesis about the synchronized emergence of periodical cicadas is that the forced developmental delay was an adaptation to climate cooling during the ice ages.

Because their brief time above ground is so fraught with danger, periodical cicadas time their synchronized emergence at night when many of their predators are sleeping. The strategy isn’t perfect, though. Male cicadas make so much noise that every predator around knows they’ve popped out of the ground.

They are very, very loud. Their chorus can reach 100 decibels in some areas. Someone on Reddit described their mating call as a “kind of high-pitched whiny vibration that goes REEEEEEEE-REEEEE, reeeee ree.”

Periodical cicadas are only found in the eastern half of the country. Some people in cicada deserts are planning to make the trip east to see them, according to the Reddit thread.

“Anyone got any pointers for this?” one person said “I’m from California and the only hordes we get are Coachella and Salesforce convention. [I don’t think] I’m ready for this.”

Cicadas aren’t for everyone, said a person who was around for the 2007 cicada emergence.

“I still mowed my grandparents’ lawn for them back then,” said the person. “I was there they day they came out of the ground, it was like a horror movie: about 12-15 per square foot emerging from the ground, leaving little holes behind, and crawling to the tree trunks. While mowing the lawn, they'd land on my shoulders constantly.

“I now live in that house, so I know what I’m in for,” the guy said. “My wife, I’ve tried to tell her. My 2-year-old, I have no idea how she is going to react. My three cats are probably going to lose their damned minds, but if one gets in the house they’ll have a hell of a time chasing it down and playing with it.”

• Should You Worry If Your Pet Hacks Up A Cicada?

Another person who was living in Cincinnati 20 years ago when Brood X emerged called it “freaking biblical for a couple of weeks.”

“Anywhere with trees, they clouded the sky and the noise level was tremendous,” the person said. “Piles of brown carcasses lined highway shoulders for miles. They were smaller than traditional cicadas and got everywhere — shoes, pants, cars, hair, bags. I can still hear the distinct, pathetic little ‘ehhhrrrkk’ sound they make when they’ve followed you inside and it’s somewhere on your clothes.

“Badminton racquets were procured to whack them down from their slow, dumb existence. They fell by the hundreds, and thousands more were right behind them.”

• Related: Yikes! Cicadas May Intentionally Squirt Pee At People

“We’re gonna get blanketed. It’s gonna be ‘Brood Where’s My Car?’ out there,” someone else said.
Not everyone is filled with dread, though.

“I am honest to god so excited,” one person said.

“First time seeing cicadas emerge in Chicago,” someone else said. “Those suckers used to headbutt me all the time in New Orleans. But I love those clumsy bugs!”

“Oh, they’re fun!” another person said. “Many years ago, a neighbor kid ate one for the news crew that stopped by.” (You read that right. Cicadas are edible.)

Another person has fond memories of a 2007 emergence, noting, “It was the most whimsical day of my 6-year-old’s life.”