Woodstock for insects? A weeks-long “festival” of “love” and “music” is about to begin in the eastern United States, where billions of cicadas will soon appear in the biggest emergence event since 2004. They’re part of a group called “Brood X,” and also the “Great Eastern Brood.” These insects will be emerging throughout the eastern US in the coming weeks, having spent the past 17 years underground, tunneling and feeding beneath the soil in their immature form.
When they finally appear above the ground, usually beginning in late April or early May of the emergence year, these cicadas will molt (shed their outer shell) one last time, growing wings in the process. This final, adult stage of their life will last only a few weeks: by July they will be dead. In the meantime, finding a mate will be, understandably, a top priority. And as far as the “music” goes: the loud, buzzing drone cicadas make is actually a mating song emitted by male insects, flexing a drumlike organ called a tymbal.
While cicadas are considered a nuisance which can cause issues for some orchards and certain crops (vegetable and flower growers apparently don’t have any cause for concern), the insects aren’t harmful to humans or animals. In fact, many people view the event as a rare chance to witness a truly awe-inspiring phenomenon. And, believe it or not, there is growing interest in cooking and eating them!
A few of the insects will probably start emerging in late April (soil temperature has a lot to do with the timing), but the largest numbers will probably begin showing up in in the first two weeks of May. Look for finger-sized holes in the ground or a tube-like extension running out of the soil. Their abandoned exoskeletons will also be visible on the trunks of trees and on the sides of buildings, and then – well, you won’t be able to miss the flying, buzzing critters themselves after things really get going.
There is still a good deal about the emergence patterns that scientists still don’t fully understand. Why the 13 or 17 year life cycles associated with the most common types of cicadas? (Interestingly, 13 and 17 are both prime numbers.) This is largely a mystery, but entomologists and other scientists speculate that emerging en masse aids the species in mating and avoiding predators successfully – after all, the birds, squirrels and other small creatures which feed on them can only eat so many!
So, if you live in the eastern US, may you survive – and possibly even take some enjoyment from – the Great Cicada Invasion of 2021!
