Beyond the noise: Loyola entomologist sheds light on the ecological importance of cicadas

By Vivian Ewing

Photos by Lukas Keapproth

June 20, 2024

A cicada clings to a stem of tall green grass.

First, the ground seems to boil. Then, thousands of legs reach up to the sky as they crawl out of the earth. The red-eyed insects emerge in droves and their screams are deafening. After 17 years, Brood XIII has returned to Chicago.  

A periodical cicada emergence might seem like something out of a horror film—maturing nymphs wait underground for years then dig their way out to mate and shriek before laying eggs and dying—but it’s natural and the insects don’t cause any harm. They’re actually quite beneficial, says Loyola University Chicago biology professor Martin Berg, PhD. He’s an entomologist, or an insect specialist, and he has a message for the cicada-wary: there’s no need to be afraid.   

In fact, cicadas may even deserve a little more love. 

“They do a lot of good at every life stage,” Berg says. “The nymphs aerate the ground which helps plants grow.” Some nymphs die underground and that’s nutritious for the plants as well. “And then when the adults come out, they’re food for a lot of other animals,” he says. The way females lay the eggs in tree branches even causes unnecessary limbs to fall. “They’re self-pruning,” he says. “Every life stage has a benefit.” 

Two dead cicadas sit near an emergence hole, where nymphs emerge from the ground after years beneath the soil.
Two dead cicadas sit near an emergence hole, where nymphs emerge from the ground after years beneath the soil.

Berg’s primary focus is on aquatic insects, but a cicada emergence presents an exciting event that brings people together. In his classes,  Berg takes students out to experience insects hands-on. The semester was already over when the emergence began in full force but he’s brought neighborhood children out to see the cicadas—and to eat them, too.  

Some people fry them or dip them in chocolate, but not Berg. “I just took them off the tree and ate them,” he says. What do they taste like? “Soft-shell crab.”  

Berg has been a Loyola professor for almost 30 years, and, in that time, he’s gotten to see many students fall in love with insects.  

“I’ve had a lot of students go onto careers in entomology,” he says. Former students have worked for the Illinois Environmental Protection Agency, the Department of Natural Resources and the U.S. Fish and Wildlife Service. One former student worked for the Forest Service, looking at the food availability of insect-eating birds, he says.

His own love of insects started in his eighth-grade biology classroom. He was tasked with creating a collection of insects and he loved the experience. “It’s the diversity,” he says. In college, he saw a future in entomology. “I was like ‘Oh my gosh, you can have a career in insects?’,” he says.  

Today, Berg appreciates the efficiency of the insect. “They can take advantage of any environment,” he says, and as for cicadas in particular: “There’s a reason they’ve been around for so long. They’re very successful.”

It certainly seems that way in the Chicago suburbs. But there are fewer cicadas in more developed, urban areas. This is because of their subterranean maturation period, Berg says. Any area where construction dug deep enough in the past 17 years would have killed the nymphs. For city dwellers looking to spot cicadas, check out open areas like parks and trails.

On Loyola’s Lake Shore Campus, try the East Quad, Berg says.

He hopes people will go out and look for cicadas with an eye on their place in the environment. “It makes people aware of what’s in their natural world,” he says. “If you educate especially young kids, they’re going to be aware that if you destroy habitats, you run the risk of negatively affecting some neat—not harmful—organisms.”

So don’t fear the cicadas. Thank them for their place in the food chain—and step carefully.