Periodical cicadas from a brood first reported by the Pilgrims at Plymouth Colony in 1634 will emerge this spring after spending 17 years underground.

Millions of the winged insects from Brood XIV are expected to make noise in Pennsylvania and 13 other states, according to Dr. Gene Kritsky, an entomologist and founder of Cicada Safari, a group that crowdsources and reviews data on cicadas.

“A lot of the places where Brood XIV is going to be emerging will be close to areas where Brood X emerged four years ago,” said Kritsky, a biology professor at Mount St. Joseph University in Cincinnati, Ohio.

The nymphs, or immature cicadas, will emerge when the temperature of soil reaches between 64 and 65 degrees.

“And also after a nice, soaking rain,” he added. “That’s when I have seen massive numbers come out. Last year in Chicago, I have never seen so many come out in significant numbers. It’s just amazing – and now that’s going to happen in your neck of the woods.”

In Pennsylvania, he predicts the action will get underway as early as the third week of May.

Once they’re above ground, they’ll climb tree trunks and shed their skin as they morph in to adults.

“It takes two full weeks for all the cicadas to come out of the ground,” Kritsky said.

Those that don’t get eaten by predators make their way to treetops.

“We call them chorusing centers,” he said of the trees. “All these males fly in and they start ‘singing’ to attract a mate. It’s basically like a gigantic cicada singles bar.”

Their singing, he said, is actually the sound made by the furious flicking of their wings.

“Around the third week is when the choruses get really loud,” Kritsky said.

He’s measured a cicada chorus at 102 decibels, courtesy of a brood emergence last year in Illinois. As a comparison, he said, the loudness of a jet landing at an airport is between 70 and 80 decibels.

The cicadas – and their deafening calls – will die off in about a month.

“They’ll be mostly gone by the end of June,” Kritsky said.

The eggs that females deposit in the slits on branches hatch after 6 to 10 weeks, and the tiny nymphs fall to the ground. They burrow into the earth and stay there for 17 years.

The brood, which last emerged in 2008, is one of the largest groups of 17-year cicadas. Its historical range includes Georgia, Kentucky, Maryland, Massachusetts, New Jersey, New York, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Virginia and West Virginia, Kritsky said.

“The first record of what’s now called Brood XIV was in 1634 by the Pilgrims,” Kritsky noted. “The Pilgrims were just amazed by it. They had never seen it before.”

He wrote extensively about the brood in his book, “The Pilgrim’s Promise: The 2025 Emergence of Brood XIV” and noted that the brood continues to emerge every 17 years in Plymouth, Massachusetts.

In addition to Schuylkill County, the Penn State Extension expects emergences in Adams, Bedford, Berks, Blair, Centre, Clearfield, Clinton, Cumberland, Franklin, Huntingdon, Lackawanna, Lehigh, Luzerne, Lycoming, Mifflin, Montour, Northumberland, Perry, Potter, Snyder, Tioga, Union and York counties.

They are all places where Brood XIV has historically occurred.

Kritsky noted that years and years ago, the United States Department of Agriculture relied on the public for cicada information. The department mailed postcards to postmasters, school superintendents and railway station conductors to ask whether they spotted the insects. In 1902, that survey yielded around 1,000 responses.

But after World War II broke out, the department ended the surveys.

“The last year the USDA did a massive, nationwide survey was 1940,” Kritsky said.

Kritsky pored through thousands of reports from USDA, newspaper articles and other historical data and found that Brood XIV cicadas were first documented in Pennsylvania in 1906.

He is hoping that folks will report cicada sightings through the Cicada Safari app, which was developed by Kritsky and the Center for IT Management at Mount St. Joseph.

With the app, users take and submit photographs of cicadas. The reports are reviewed and help map cicadas’ ranges.

Since its launch in 2019, more than 250,000 have downloaded the app and have submitted close to 750,000 reports of broods that hatched since then.

More information, including activities for children, is available at cicadasafari.org.

Another website, CicadaMania.com, also tracks cicadas emergence locations across the country.

“The county list is based on historical information,” said Dan Mozgai, of CicadaMania. “So, they once appeared there, but their populations might have dwindled to being too small to reproduce — so there might be none left in 2025. We’ll have to see.”

He noted that cicada populations are dwindling because of habitat destruction and pesticide use.

“Anytime we build a new road, neighborhood, warehouse, etc., we destroy cicada habitat,” Mozgai said. “So, there will be less and less each emergence.”

Dr. John Cooley, associate professor of biology and evolutionary biology at the University of Connecticut, expects off-cycle cicadas, or stragglers, to emerge this spring.

“(Brood XIV) is closely associated in time and space with other broods that are potentially throwing off lots of stragglers,” he said.

The stragglers emerge in places and in years when they are not expected.

“So I think the best guide is what people saw in 2008” is what they will see in the spring, Cooley noted.

His research can be found at www.cicadas.uconn.edu.