
The cicadas are back in the Greater Washington, DC area. You know they have arrived when you hear their distinct chirps and see them on the trees, bushes, and sidewalks. Some say they are four years early. It is a source of debate among entomologists. Many say these 2017 visitors they are a different brood of Cicada (colloquially called Periodical Cicadas) than the ones that cycle visits every 13 or 17 years. In any event, I personally welcome their valiant return Inside the Beltway.
A good summary article of the perhaps puzzling visits to Maryland, DC and Virginia “Mystery Cicada Swarms Emerge across DC, Northern Virginia in 2017” provides good insights for cicada aficionados.
To me, cicadas are my favorite bug. They do not bite, they look quite unusual, and they are a true wonder of nature. I enjoy watching them. Their appearance reminds me of something prehistoric and dinosaur-like in a charming way. Their eyes are expressive and they seem to have an exoskeleton shell that acts as a coat of armor, albeit for a short few weeks before they mate and disappear or are victimized by bird predators.
What differentiates cicadas from other bugs are their life cycles. Cicadas do spend most of their lives underground which certainly makes them biologically unique to other bugs and critters. According to an excellent cicada resource website: www.magicicada.org, “Periodical Cicadas are found only in eastern North America. There are seven species — four with 13-year life cycles and three with 17-year cycles. The three 17-year species are generally northern in distribution, while the 13-year species are generally southern and Midwestern. The periodical cicadas can be divided into three species groups (-decim, -cassini, and -decula) with slight ecological differences. Magicicada are so synchronized developmentally that they are nearly absent as adults in the 12 or 16 years between emergences. When they do emerge after their long juvenile periods, they do so in huge numbers, forming much denser aggregations than those achieved by most other cicadas. Periodical cicada emergences in different regions are not synchronized, and different populations comprise the 15 largely parapatric periodical cicada “Broods,” or year-classes.”
Whether this group or brood of cicadas is of the 17-year genus or “Periodic Cicadas” is really not an issue that I care to ponder. I will leave it up to the insect professionals. All I know is that I appreciate the cicadas and their cycles and wish they would return more often.