The Great Eastern Brood or the periodical cicadas, as they’re known, are different than annual cicadas. They spend almost their whole lives a foot or two underground, living on sap from tree roots. Then, in the spring of their 13th or 17th year, depending on the type, mature cicada nymphs emerge for a brief adult stage, synchronously and in huge numbers. They mate and then die, and their newly hatched offspring drop to the ground and burrow in for the next 13 or 17 years.

       Parts of 15 states, as well as Washington, DC, are hearing the romantic serenades of males in trees, trying to attract females. The states are Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia and West Virginia. The return of the cicadas usually starts around early- to mid-May and runs through late June.

       The bugs typically begin to come out when soil temperatures 8 inches (20 centimeters) underground reach 64 degrees Fahrenheit (18 degrees Celsius), with a warm rain often triggering their emergence. Cooler weather than usual in parts of the US this year delayed their appearance in some places, and in others they are not showing up at all, due to development, pesticide use and invasive species.