Billions of periodical cicadas are swarming the Eastern U.S., marking their 17-year emergence.

Billions of periodical cicadas from Brood XIV are swarming parts of the Eastern United States, including Georgia, southern Ohio, Kentucky, Cape Cod in Massachusetts, and Long Island, New York. These cicadas emerge every 17 years when the soil warms to 64°F (18°C). After mating, females lay eggs in tree branches, and the cycle begins anew with the hatched nymphs burrowing underground. Their loud buzzing sound marks the arrival of spring.