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Why Are There Suddenly So Many Cicadas Around?

Teenagers might think they are world-wise, but any youngster who hasn't reached his or her 18th birthday is in for something new this year: Brood X cicadas. Every 17 years, the black-bodied, red-eyed insects emerge from beneath the dirt where they have been hiding and spend their adult lives – typically, only a few weeks – in the sunshine of spring. Last seen in 2004, they began appearing above ground earlier this month.

Brood X cicadas are endemic to the eastern United States, and because they don't swarm and are weak fliers, they tend to stay within very close proximity of where they emerge. There are 12 broods of 17-year cicadas, with Brood X being the largest. And when they come, they number in the billions. Large groups of cicadas can make a buzzing noise that reaches 100 decibels, or the equivalent of a jet taking off. For those concerned about the sudden appearance of so many large red-eyed bugs, it should be noted that the cicadas neither bite nor sting, and tend to stay away from urban areas. Nor will they decimate gardens or crops.

All about cicadas:

  • Cicadas and locusts are not the same thing: cicadas are "true bugs," whereas locusts belong to the same order as grasshoppers and crickets.

  • There are approximately 3,400 species of cicadas, most of which appear every two to five years.

  • The only place in the world where 13-year and 17-year cicadas exist is the eastern region of the United States.

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    • In early May 2021, Brood X cicadas began emerging across the eastern U.S. after 17 years underground.
      In early May 2021, Brood X cicadas began emerging across the eastern U.S. after 17 years underground.