A handful of freshly emerged cicada nymphs. They must emerge in enormous numbers to overcome predators. (credit: M.J. Raupp)

Billions of cicadas are ready to emerge from underground to take part in a noisy mating ritual 17 years in the making.

Experts are busy helping Maryland residents prepare for this rare phenomenon. Here are answers to some of the most common questions:

What are cicadas and why does this happen?

The periodical cicada is a sap-sucking insect known for its boisterous mating calls and enormous synchronous emergence on multiyear cycles. This particular group is known as Brood X, and it’s surfacing for the first time since 2004.

“They emerge simultaneously in geographical regions in such massive numbers simply so that they fill the belly of every creature that eats them. And there will still be enough to sustain the species,” said University of Maryland entomologist Michael J. Raupp.

Raupp, known as “the Bug Guy,” says the periodical cicada’s lifecycle spans 17 years in order to outmaneuver the predator-prey cycle.

“No predator can track them in time. No bird, squirrel or raccoon lives long enough to take these guys out if the lifecycle is so long,” he said. “Sure they’re going to eat you, but there is never going to be enough predators to overwhelm you and cause your extirpation.”

When are the cicadas coming? For how long?

The first cicada was identified above ground on April 19 in Towson. Once the soil reaches 64 degrees, the insects generally surface en masse. It’s a matter of days or weeks before huge crowds of cicadas are out and about, and begin their transition from nymph stage to winged, red-eyed adulthood.

The cicadas will be around for most of May. Seventy-five percent of the emergence will occur by Memorial Day, experts predict.

It will tail off the first week of June. By July 4th, they’ll be finished.

Are they coming to my neighborhood?

There will be clusters of cicadas all over the city. Baltimore’s city arborist Erik Dihle says cicadas are expected around Druid Hill Park, Herring Run, and other park areas across the city where trees have been standing for more than 100 years.

Residents can also look for them near the forest’s edge, such as in and around Gwynns Falls/Leakin Park.

“You’re going to be looking for dime-sized holes,” Raupp said. “Go out and look out under big old trees, and you’ll see these holes.”

Underneath the holes are “exit galleries” where nymphs waiting for the right conditions to start the massive mating party.

“There’s still a lot of holes in our knowledge to figure out where they are and when they appear,” he said.

Raupp is encouraging residents to download the Cicada Safari app and report cicada sightings. Users snap a pic of the bug, and the app uses geolocation and timestamp information to build a model of the brood.

Will cicadas damage my plants?

Cicadas are sometimes confused with locusts which can swarm an area and quickly devastate an entire crop. But cicadas are more similar to the aphid. They’re not coming to devour the area’s entire plant life.

Female cicadas will do some damage to twigs and branches as part of the egg-laying process.

Female cicadas make slits into the bark of twigs to deposit eggs. She can lay between 400 and 600 eggs. When they make that slit, Dihle said, that portion of the branch will die from the wound.

“We’re concerned of course, but the damage is incidental.” Dihle said, adding it won’t have much an impact on larger trees. But damage to young trees or shrubs “can either put them in decline or stunt their growth.”

Residents looking to protect their plants can get the netting at a local hardware store.

Are cicadas bad for my pets?

Consuming cicadas generally won’t harm pets.

“Certainly, dogs love them, all of the smaller mammals, birds do. It will plump them all up,” said Mary Hardcastle, director of the Carrie Murray Nature Center.

She says it’s natural for pets to enjoy the “abundance on steroids.”

The center is hosting a public program called Cicada Craze at 1 p.m. on Saturday, May 22 for residents looking to “learn about cicadas, their emergence and role in our ecosystem.”

Raupp did caution owners to not let pets eat too many cicadas or dogs may come inside and “woof them up on your rug.”

Should I be concerned for my children?

“They don’t bite; they don’t sting; they don’t carry away small children,” Raupp said. “There is really nothing to fear about cicadas.”

The nature center runs a nature preschool, and Hardcastle says that although cicadas pose no threat to children, staff is considering how to approach the emergence.

Even for children with experience interacting with insects and nature, it could overwhelm.

“It’s not the same as the fear of bees or wasps, so we’ll need to think about that,” she said. “We’ll do the same thing we do with anything that’s new: Find the excitement and foster the curiosity versus the fear. Kids do tend to lean into the curiosity and wonder.”

Child participating in a nature program with Carrie Murray Nature Center examines cicada molting. Photo courtesy Carrie Murray Nature Center.

Can I eat them?

The answer is yes. And Raupp would direct Baltimore ominvores to the CICADA-LICIOUS cookbook, created by Jenna Jadin and the University of Maryland Cicadamaniacs in 2004 (the prior cycle).

He’s partial to the chirper tacos, but also is a fan of the raw, freshly molded cicada for its “buttery texture and nutty flavor.”

“You just walk up to it and grab it. These are not clever creatures,” Raupp said adding that cicadas are easier to catch in the morning before they’ve warmed up.

Do not eat cicadas if you have a shellfish allergy. The same allergen in the exoskeleton of shrimp is contained in the cicada shell.

The bugs also make good fishing lures. Artists can craft with molted cicada shells and wings. And of course, many around Baltimore may just want to enjoy the loud buzzy song of the summer.

“Make the event as enjoyable as possible. This happens nowhere else on planet Earth, and it only happens a handful of times in a person’s lifetime,” Raupp said.