(Listen to the radio version here.)
In the late summer of 1956, my family moved to Northlake, a blue-collar suburb of Chicago near O’Hare Airport. At that time, there were plenty of planes, but jets were few and far between. At first, I remember being thrilled when a real jet plane passed over, but jets lost their charm as their flyovers increased relentlessly. Even inside the house or our school, with the doors and windows closed, the rhythms of conversations became bizarrely disjointed—when a jet passed over, we’d halt in mid-sentence and pick up right where we left off as the noise dissipated, over and over.
If we’d moved into our house just a month or two earlier, when the 17-year cicadas in the Northern Illinois Brood (“Brood XIII” as named by Charles Lester Marlatt in 1907) were calling at full throttle, my parents would have hightailed it back to the city, but we’d unwittingly moved after the cicada breeding period was over.
My parents sold the house in 1971, two years before the next cicada emergence, so I never realized we’d lived in the epicenter of these wondrous creatures until June 2007, when I visited my sister in an adjoining suburb, Elmhurst. Her house was just as close to the airport as our childhood home but new enough to meet strict new noise codes in the vicinity of O’Hare, so her windows and doors were soundproof.
My 2007 visit coincided with the emergence of that Northern Illinois brood of cicadas. When we were inside, we didn’t notice them, but the moment someone opened a door, the din was overpowering and lasted way, way longer than a passing jet. It’s hard to get accurate figures, but several people with sound meters during the 17-year-cycle Great Eastern Brood (Brood X) emergence in 2021 measured the critter noise at 90–100 decibels, well over the 85 dB noise limit at which the CDC recommends ear protection.
Periodic cicadas belong to the order Hemiptera, the “true bugs.” Some people call cicadas locusts, but they’re not at all related—locusts belong to the order Orthoptera with grasshoppers. Both insect orders provide important food for birds.
All the periodic cicadas belong to the genus Magicicada. These are the longest-lived of all the insects in the world and are found only in eastern North America. Every species has a 13- or 17-year life span, every individual spending almost all that long life underground as an immature nymph, feeding on xylem fluids from the roots of deciduous trees. In late spring of their final year, about when soil temperatures reach 64º F, the mature cicada nymphs emerge from underground in synchrony, in almost unimaginable numbers. They molt out of their final nymphal exoskeleton and voila! Suddenly they are cool-looking adults with brilliant red compound eyes and gorgeous translucent wings outlined in orangey gold.
In a few days, after their new exoskeletons and wings harden, the males gather in “chorus centers” where they vibrate a pair of drum-like structures, called tymbals, on the sides of their abdomen to create that high-pitched, astonishingly loud buzz.
The noise attracts female cicadas of course, but that can’t be the entire explanation for the volume. Cicadas are big and tasty—even some people eat them—and represent a lot of calories for birds who are feeding young right when this abundant and nutritious baby food is out there for the taking. Cicadas are weak fliers, do not bite or sting, and their defenseless bodies don’t produce toxins or a bad taste to ward off birds, but I suspect the loud calls keep at least some avian predators away. I’ve not been able to find any studies that confirm this or offer better reasons for the loudness.
After mating, each female cicada uses her ovipositor to make a V-shaped slice into a twig of a deciduous tree to deposit 24–48 eggs. Her adult life lasts just two or three weeks, but during that time she’ll mate again and again, producing a total of 600 eggs or more, which will hatch in about 6–10 weeks, a month or two after their mother has died. The tiny grubs drop to the ground, burrow into the soil (enriched by the rotting bodies of so many adults), and start munching on tree roots.
This year’s emergence will be historical because, for the first time since 1803, both the 17-year-cycle Northern Illinois Brood (Brood XIII) and the 13-year-cycle Great Southern Brood (Brood XIX) will emerge in the same season. This won’t affect how many cicadas people experience in their own neck of the woods, but the affected swath of the eastern U.S. will be huge. It won’t happen till spring, but it’s already getting a lot of news coverage. I’m concerned that people even less in touch with nature than they were 17 years ago are going to panic.
Starting in late May 2021, many birds were found dead and dying in D.C., Virginia, Maryland, West Virginia, Kentucky, and Ohio, precisely when and where the 17-year Great Eastern Brood (Brood X) was emerging. The birds, including Common Grackles, Blue Jays, American Robins, and European Starlings, suffered from eye swelling, a crusty discharge, and neurological problems. Several laboratories conducted necropsies, but no pathogens, bacterial or viral, were found to be causing the deaths. Many people studying the issue believe the birds had been damaged by insecticides from panicky people, especially because the affected species often walk and feed on lawns where sprayed pesticides accumulate. (I wrote about this in June 2021.)
So far, this year’s news coverage is focusing on the historic nature of the coming emergence (these two large broods haven’t emerged in the same year since Thomas Jefferson was president), and on the infernal noise and huge number of cicadas involved. I’ve seen stories mentioning shovels and even snowplows to remove the carcasses after their brief life above ground. I’ve also read lots of exaggerations about how “literally deafening” their noise will be. Russ and I are planning to go to Chicago to enjoy this wondrous phenomenon, and for me to get better photos. We’ll wear ear protection of course, exactly as people should do when mowing their lawn, using power tools, or riding a snowmobile or ATV, but we, and our hearing, will be perfectly safe.
A few news stories do mention that pesticides won’t “help” because there will be too many of the insects to be “effective,” but so far I haven’t seen any coverage at all about the collateral damage insecticides pose to birds and other wildlife, pets, and people. I still know people—educated adults who support most environmental causes—who grab for the spray bottle whenever they see a spider in the house. I’ve even witnessed an ostensibly educated mother grab a can of insecticide to kill a small beetle on a highchair tray while her child was sitting, right that very moment, in the highchair! Seriously. Imagine that! (When I realized what she was about to do, I told her to let me handle it, got a tissue, caught the little insect, and set it outdoors.)
This year is already extremely frightening for me in terms of a great many issues. Now, thinking about people pouring and spraying pesticides on the world we all share, is bringing my fear levels to new heights. We’re supposedly the smartest species on the planet, but we have a very poor track record for learning from our mistakes. Cicadas, like small children, may be loud but they’re also innocent. They’ll be aboveground for just a very few weeks after living silently underground for 17 years. We can enjoy them or avoid them as we choose, but we must do it safely, for all of us.