Residents of 15 eastern states and the District of Columbia can experience "a rare wonder of the natural world" this spring—if they can get over the noise. Billions of cicadas are expected to emerge from the ground for the first time in 17 years in Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia, as well as in Washington, DC, reports the Guardian. These areas are home to a group of red-eyed periodical cicadas known as Brood X, or the Great Eastern Brood, which hide out underground in 17-year cycles, per the Detroit Free Press. The brood last emerged in 2004. That means there should be swarms appearing as the weather warms around the middle of May. People in West Virginia, Virginia, and parts of North Carolina witnessed this same thing last year.
"They may amass in millions in parks, woods, neighborhoods, and can seemingly be everywhere," a Michigan State University entomologist tells the Guardian. He warns that pets who eat the nonbiting insects may get sick, though that doesn't appear to be the case with humans. Humans and pets will both have to deal with the din, however. The mating call of male cicadas—produced through vibrations in two membranes on either side of the abdomen, called tymbals—can generate the same level of noise as a motorcycle revving its engine, per the Guardian. The cicadas—which have spent the last 17 years in wingless form, slurping up sap from tree roots—are expected to emerge as the soil reaches 64 degrees Fahrenheit. Females will then lay eggs in trees. Once hatched, nymphs will burrow into the ground to repeat the cycle. (Read more cicadas stories.)