Cicadas evolved a key survival technique: overwhelming numbers. There’s just too many of them to all get eaten when they all emerge at once, so some will survive and reproduce, Raupp says.
This is not an invasion. The cicadas have been here the entire time, quietly feeding off tree roots underground, not asleep, just moving slowly waiting for their body clocks tell them it is time to come out and breed. They’ve been in America for millions of years, far longer than people.
When they emerge, it gets noisy — 105 decibels noisy, like “a singles bar gone horribly, horribly wrong,” Cooley says. There are three distinct cicada species and each has its own mating song.
They aren’t locusts and the only plants they damage are young trees, which can be netted. The year after a big batch of cicadas, trees actually do better because dead bugs serve as fertilizer, Kritsky says.
People tend to be scared of the wrong insects, says University of Illinois entomologist May Berenbaum. The mosquito kills more people than any other animals because of malaria and other diseases. Yet some people really dread the cicada emergence, she said.
“I think it’s the fact that they’re an inconvenience. Also, when they die in mass numbers they smell bad,” Berenbaum says. “They really disrupt our sense of order.”
From the archives (September 2011): Stinkbug invasion: Bane to most, bonanza for some
But others are fond of cicadas — and even munch on them, using recipes like those in a University of Maryland cookbook. And for scientists like Cooley, there is a real beauty in their life cycle.
“This is a feel-good story, folks. It really is and it’s in a year we need more,” he says. “When they come out, it’s a great sign that forests are in good shape. All is as it is supposed to be.”
From the archives (May 2013): The Wall Street cicada index