Flight Lines: Noise maker lives most of life underground, emergence tied to warm summer days
The first time I remember hearing it was in 1983 while living in Columbus, Miss. By the time summer arrived, things were as hot and sticky as this North Dakota native had ever experienced. Nights never did cool off and days, oh those days. Around July, I became aware of an extremely annoying buzz coming from the trees in the area. In fact, during jogs along wooded streets the sound was nearly deafening at times. And don't even try to leave your windows open at night; the noise made it impossible to sleep. The source of this curiously loud buzz - I was to find out - was an insect known as a cicada (si KAY da).
There are around 3,000 cicada species worldwide but not all of them are well understood nor even classified. All are members of an order called Hemiptera, which includes such familiar insects as leafhoppers and spittlebugs. Cicadas are known for their widely-spaced eyes on large blunt heads, and transparent wings with prominent veins.
It took me awhile to track down the noise makers in Mississippi. The first clues were the holes in the soil under the trees. Then I kept finding empty body shells (exoskeletons) with split backs on the bark of trees. They looked rather large and prehistoric, like something out of Jurassic Park. Something had obviously emerged from them. Finally, I found live ones - ugly beasts built like miniature rhinos, which would find themselves right at home in the bar scene from Star Wars. The adults were nothing attractive either, having blood red eyes and a seemingly ferocious mien.
What I was seeing was the nymph of the insect which spends most of its life underground sucking tree sap from the roots of trees. At the end of the insect's underground life, the last stage emerges, crawls up onto tree bark or anything convenient, and molts into a winged adult.
Making cicadas one of the most recognized insects to peoples all over the world is its size. Some species can be quite large (a Malaysian species can reach six inches). Couple body size with the fact the insects often emerge in large numbers and it leaves little wonder that many cultures treat cicadas as a source of protein in local diets.
To Americans, the most familiar ones are the periodic cicadas which can spend as many as 17 years underground before emerging as winged adults. Each brood, in fact, of the 17-year cicada is designated a Roman numeral to differentiate it from the others (there are at least 13 broods). Brood X is known at the "great eastern brood" due to its large population and geographic coverage. This is the one that will usually generate a national news story when it occurs, most recently 2004.
One of the more amazing feats of the natural world is how millions of winged adults can emerge within hours of each other over hundreds of square miles after having just spent 17 years of silent and solitary existence under the ground.
Curiously, the synchronous emergence of periodic cicadas is thought to be part of a survival strategy known as "predator satiation." That is, so many millions of adult cicadas appear at the same time as to overwhelm whatever predators might eat them, leaving the great majority unharmed to produce yet another generation.
For some reason I don't remember hearing this insect in West Fargo while growing up. It's entirely possible I either ignored it, I passed the sound off as crickets buzzing, or I was too busy with other things to even notice. I hear them every summer now. Ours are not the famed periodic cicadas of the southeast, the ones we hear are likely annual ones (Tibicen sp.) collectively called 'dog day' cicadas, due to the fact the adults emerge in mid to late summer. And yes, they are still buzzing loudly.