In just a few weeks, more than a dozen states across the eastern United States will be awash in billions upon billions of cicadas. After spending almost two decades underground, the collection of bugs that researchers have dubbed “Brood X” will take to the treetops for a once-in-their-lifetime, cacophonous sexfest.

But while Brood X once appeared in New York, northern New Jersey and Connecticut, this spring may be cicada-free.

Past reports of Brood X included much of the Tri-State area in their ranges. But the last time they came above ground in 2004, they only emerged about as far north as central New Jersey and eastern Pennsylvania.

The cicada broods for the last 200 years have been declining on Long Island in particular.
Dr. Michael Raupp, University of Maryland entomologist

“The cicada broods for the last 200 years have been declining on Long Island in particular,” Dr. Michael Raupp, an entomologist at the University of Maryland. “We're just keeping [our] fingers crossed that we will see them at least one more time here in 2021.”

The Brood X cicadas set to erupt from the ground this spring are different from the fast, green ones found in parks and wooded areas across the region each summer. Known as “periodical cicadas,” these species spend years feasting on roots and tree sap before bursting from the soil to mate. Brood X (as in the Roman numeral for “10”) is just one of a dozen groups that researchers have identified as emerging on a 13-year or 17-year cycle, though according to Raupp, it is one of the largest.

“In my backyard right now, underneath my old maple tree, I've got 30 cicada holes per square foot. That translates into 1.3 million cicadas per acre,” Raupp said. ”They're going to be a lot of cicadas that people are going to be running into this year.”

Cicada emergence holes over a square foot of ground.

Courtesy of M.J. Raupp

Based on studies of previous Brood X emergences, Raupp says there could be anywhere between billions and trillions of cicadas preparing to scramble from their underground galleries and into the treetops, where they will let forth their distinctive buzzing in hopes of mating and passing on their genes.

At least, that’s the case outside the tri-state area. During the last Brood X revival back in 2004, only a handful of cicadas were sighted in central Long Island. Even though that gives researchers some hope that some may still emerge there this year, that small showing could have been a sign of a critical decline, considering cicadas rely on sheer numbers to survive being picked off by predators.

Brood X cicada in the Govanstown neighborhood of Baltimore

Jaydro via Flickr/CC BY-NC-ND 2.0

“There were historically out there on Long Island. There's a whole set of miniature broods out on Long Island,” said Dr. John Cooley, an evolutionary biologist at the University of Connecticut. “The question of the hour is, are they still going to be there because one by one they've been going extinct?”

If May comes and goes without sight nor sound of a Brood X cicada on Long Island, American Museum of Natural History invertebrate curator Dr. Jessica Ware believes the culprit is most likely the encroachment of human communities on the forests that these insects call home.

“If trees are cut down for a parking lot or for a housing subdivision or what have you, then all of those juveniles that are underground, they're dead. They're not going to make it,” Ware said.

Hundreds of cicadas scaling a trunk to molt their exoskeletons.

Courtesy of M.J. Raupp

For New York City-area cicada-lovers, spotting Brood X will most likely just mean taking a day trip a few hours southeast. And if they miss this year’s emergence, Brood II is scheduled to make an appearance in northern New Jersey in 2030.

But even if Brood X’s emergence is a dud in New York, northern New Jersey, and Connecticut, Ware believes it still presents a good opportunity to teach people about the long-term effects of human behavior on the environment. Just because periodical cicadas only make themselves known to us every 13 or 17 years doesn’t mean they aren’t present during all that time.

“Certainly this isn't the first brood or part of a brood to go locally extinct. There are other whole entire groups that have gone extinct over the last hundred years as people changed that landscape for agriculture and then for subdivisions and what have you,” Ware said. ”It should definitely make us feel responsible.”