While Washingtonians should be familiar with the cicadas’ periodic appearances that come with a fair amount of noisy chirping and buzzing, typically these “broods” occur roughly every 17 years. However, this year, there is a particularly rare “double brood” event taking place, which means that once again Cicadas are going to be taking the country by storm once the weather warms up.
The so-called, “double brood” is so aptly named because it is the result of two different cicada breeding cycles synchronizing, one that occurs every 13 years and another that occurs every 17 years. While it may sound strange, the rarity of such an event is so extreme that the last time a “double brood” event took place was 221 years ago – in 1803. This means, that for those Washingtonians who enjoy U.S. history, when the last “double brood” event took place: Thomas Jefferson was president, there were only 17 states in the United States, and “The Star-Spangled Banner” hadn’t even been thought of yet.
According to NBC News, the country’s Midwest and Southeast regions will see the most of the cicadas, beginning as early as April.
The two cicada brooding cycles, which are known as Brood XIII and Brood XIX, won’t align at the same time again for another 221 years after this year, so you can certainly consider it a once-in-a-lifetime occurrence.
What are cicadas?
Despite their size and potentially displeasing appearance, these insects are just about completely harmless. They spend the vast majority of their time underground, where they get their nutrients from consuming tree roots. After a set period, one of the two brooding cycles will go above ground to find a mate and reproduce to keep the cycle going, in some years it will be the brood from the 13-year cycle, and in other years it may be the brood from the 17-year cycle, in this case, it just happens to be the brood from both cycles, which means that there will be even more cicadas than “normal”. When the year comes when they are finally ready to go above ground, they usually wait until spring temperatures are consistently around 60 degrees and they buzz around making their “music” to find a mate. Typically, this lasts about a month and is a pretty difficult sound to ignore, considering the mating call can reach up to 100 decibels!
While the ‘singing’ may be a mild nuisance, to some, the cicadas’ “shedding ceremony” is certainly not something many look forward to. By “shedding ceremony”, we’re referring to the fact that cicadas malt their exoskeleton when they first emerge from the ground, the “shells” that they leave behind are far from a pretty sight. Once the insects have ‘shed’ their nymph exoskeleton, the mature cicada can, quite literally, spread its wings and fly.
Throughout their month-long mating period, the cicadas are in a mad dash to lay their eggs before they reach the end of their life span. This means, that by the time summer rolls around most, if not all, of the cicadas will have died off and planted eggs in the ground to continue the cycle. Fortunately, Washington, D.C. is just on the brink of where the cicadas are expected to emerge, so while Washingtonians may get to experience some of this phenomenon directly, it likely will not be as severe as it will be in the states south of The District.