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Why Will This Spring Be Filled With Cicadas?

Cicadas on a tree
(Image: Getty Images)

Do you remember the year 2004? Let's take a little stroll back in time. Back to when Mean Girls was on the big screen, Usher’s "Burn" was heating up the Billboard charts, and the TV show Friends aired its final episode. Also, that was the last time 15 states in the US experienced the 17 year periodic Cicada emergence! If we move forward 17 years from then that takes us to today and the process is happening again. Why will this spring be filled with cicadas?

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This spring marks the return of the Brood X cicadas! Brood X, also known as the Great Eastern Brood, is the group that's currently emerging and also has the longest lifecycle among cicadas. Cicadas do emerge every year, but this particular group’s appearance only happens every 17 years. 

Here’s how it goes down: They crawl out of the ground, shed their exoskeleton, and fly around their region looking for a mate! 

Their mating calls, made by the males, are among some of the loudest sounds in nature clocking in at a whopping 100 dB, about the same volume as traffic or car horns! Once successful mating has happened, female lay the eggs, and the little nymphs hatch and crawl underground to feast on plant and tree roots for nourishment. They’ll stay underground for 17 years until they are ready for their big above-ground comeback to follow in their parent’s footsteps of mating and continuing the cycle of life. 

Once these cicadas have mated, they've basically fulfilled their life's mission and die off. Even in their death they serve a vital function for their ecosystems by providing a feast for many animals that eat them both dead or alive and their remains also serve as fertilizer for area vegetation. And, yes, some humans to enjoy them as a low-carb gluten-free treat, for adventurous eaters. Brood X emerges in big numbers as well. There are actually billions of cicadas expected to be seen this spring. Scientists estimate there can be about 1.5 million per acre or 34 cicadas per square foot! 

Their periodic emergence and mating schedules are a unique and fascinating way to observe the intricate rhythms created by their environments and their evolution. A circadian rhythm so to speak! Keep your ears peeled this spring, there's a 17 year periodic buzz in the air, science fans! 

More Cicadas: Need a little look at a previous cicada emergence we covered? Check out the 2013 article on the Brood 2 emergence.