Thursday, May 20, 2021

17 Year Cicadas Rise to the Occasion

It's a good thing the lawnmower refused to start on Monday, because on Tuesday morning, carrying our aging dog down the patio steps to the backyard, I saw that the 17 year cicadas had emerged overnight, and had used the long grass stems as a perch upon which to molt. 
They clung to the stems motionless, their new exoskeletons hardening, their wings drying in the morning sun. Were those brand new red eyes looking at me, or at everything all at once? Beside them was the empty shell of their former selves--the nymphs that had lived the past 17 years underground in patient immaturity, chowing down on tree roots. 

The night before, my daughter had heard the rustlings of leaves as she sat on the front steps. As dusk turned to dark, the million Magicicada march to adulthood had begun.

The immature nymphs had been preparing for this moment for some time, plotting their upward mobility, each having dug a tunnel to the surface. We had encountered them for weeks prior, slicing through their tunnels while digging holes, exposing their excavations while moving wood. I imagined them all stationed some distance down their tunnels, facing up, sensing the temperature of the air above them and the ground around them, ready to respond with fascinating unanimity to a cue only they could feel. 

I decided to bone up on them. What was wikipedia like 17 years ago? That which once was ridiculed, like "made in Japan" or "made in China," has become the information equivalent of what Deep Blue became in chess. Miraculously, it has evolved into a remarkably accurate and thorough source of information, encyclopedic, as it 'twere. I was sure people would find a way to mess it up. But no. Great to be wrong sometimes. Could this capacity to filter out the worst inclinations of humanity be applied to other areas of the internet?

Scrolling down through the wikipedia page on "periodical" cicadas, my simplistic assumption that 17 year cicadas emerge everywhere in the same year was blown out of the water. There are many different "broods" in the U.S., each with a different timing. In any given year, there's a brood of 17 or 13 year cicadas emerging somewhere. Virginia has seven different broods. New Jersey has three. Princeton's cicadas are part of the "great eastern brood," which extends from New York down to Georgia and out to Illinois. Is it called great because the brood extends over such a large geographic area, or simply because Princeton is included? We don't know. 

One thing the wikipedia entry doesn't explain is why I would have documented a considerable emergence of periodical cicadas in Princeton in May of 2017. The closest emergence in the wikipedia chart for that year was in North Carolina.

Can we eat them? I love this short article in the Smithsonian, which gives tips for gathering and cooking. I didn't take it personally when the article states that "Females are preferable for their protein-filled abdomens, while males offer little substance." The author of the article, someone named Twilight, must have enjoyed crafting sentences like "Marinating live bugs in Worcestershire sauce also helps weed out guys." It got me to wondering if I, too, would collapse if slow-cooked in vinegar, while the ladies all around me grew more tender by the minute.


One thing's for sure, this will be the most photographed generation of 17 year cicadas ever. For the next month or two, while their bus-with-wings bodies fill the air outside, they'll also be zipping around in posts, texts and tweets.

There's lots to read about why their periodicity (13 or 17 years) is in prime numbers. And why kill so much time underground before emerging en masse? It certainly makes it hard for predators like cicada killer wasps to expand their numbers sufficiently to take advantage of the sudden abundance of prey. Kill time or be killed--that's the logic.

And very interesting to read that moles do well the year prior to the emergence, as the cicada nymphs grow in size in preparation for their coming out party. Might the many moles feasting on growing cicada nymphs underground have had something to do with all the digging up of lawns by foxes, skunks, and raccoons reported last fall?

Trees are going to take a hit, as the female cicadas start cutting into twigs to lay their eggs. I remember seeing twigs littering the ground seventeen years ago, leaves still green, particularly under oaks. And I remember wondering what kind of world those cicadas would find when they next emerged, given the radical changes in climate we've set in motion. Thus far, not so much change in New Jersey. We've been lucky so far. I worry, though, as the mass combustion continues, and our deceptively shallow atmosphere fills with the invisible, transformative gases--the exhalations of an economy at odds with the nature we depend upon. More personally, it didn't even occur to me, seventeen years ago, to wonder if I'd be around for the next emergence. Now, that distant rendezvous is harder to take for granted. Cicadas aren't the only species playing a numbers game. It would feel better, this personal passing of years, if we weren't taking many of the glories of nature down with us. Whatever Happened to Forever is a one minute play I wrote that deals with this, at 8:49 in this video

This awareness of future endings stirred me to live this moment in cicada history more intensely. Eating dinner on the patio, I became aware of a prickly sensation on my legs. Normally, I would have brushed them off. Instead, wishing to experience their emergence fully, I let them climb. People have given me various nicknames over the years--"plantas", "the plant man"--and it's starting to look like even the insect world thinks I'm a tree. 

At one point, around the time I was polishing off my last shish kabob, I had six of them climbing the mountain of me. They had trouble with my hair, with most falling off before reaching the deceptive summit of my knee. But one was successful in making a nearly full ascent, climbing up to my shoulder, then ascending my neck and cheek. Only my sideburn and hairline proved unsurmountable, at which point it fell off, only to begin the climb again. 

After dark, I went out back to have another look at the lawn. A few more had climbed the grassblades. As they emerged from their shells, they showed two black spots just above the eyes, like dark eyebrows. But the unmowed lawn proved not to be the really big show.

Things really got interesting when I happened to look among the perennials. This purple coneflower looked like a Christmas tree with cicada ornaments, in all phases of metamorphosis. 

There's a bit of acrobatics to their molting. They do a slowmo backflip out of the shell, then bend up and grab their old skin, clinging to the shell of their former selves as they pull the rest of their abdomen out to hang free. Then it's a matter of unfolding and slowly expanding the wings, which look like little nubbins at first. 

A lot can go wrong in this stage. Some had wings that didn't grow out right, with one or the other being shorter and misshapened. 

When you google the cicadas as food, a study comes up warning that cicadas can accumulate a lot of things during their 17 years of underground munching, one of them being mercury. I don't know if it's a big concern. Many of our foods have traces of mercury. But it's worth wondering whether deformations in cicadas during molting is increasing as we continue to dig chemicals out of the earth and spread them around.

Another cicada had the bad luck to attract one of the slugs that was also seen climbing up foliage last night.

Many were having trouble finding a good place to climb. One even hitchhiked into my room and tried to climb into this blog post.


By morning, the cicada ornaments on the purple coneflower "tree" had darkened. Their wings and exoskeletons will slowly harden over the next few days. Though the coming din may grow tiring, it's still pleasurable to read that the adult males gather in something akin to a men's choir to sing to the females. Examples of nature's abundance, more rare now, are stunning to behold. We're in the midst of one now. 





5 comments:

  1. I’m so glad the cicadas have a good friend in Princeton.

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  2. Are you ready for the cicada invasion? In this episode, Neil deGrasse Tyson and co-host Negin Farsad sit down with entomologist Jessica Ware to answer your questions about the millions of cicadas emerging this summer after 17 years underground.
    https://podcasts.apple.com/us/podcast/cosmic-queries-cicada-invasion-with-jessica-ware/id325404506?i=1000518735432

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  3. So amazing! I have been taking many photos of all different stages of metamorphosis of the Cicadas around the Oak Tree at the back of my house.

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  4. Just went to check on my pawpaw sapling; found many cicadas clinging to it, who I hope do not find this wee tree attractive for egg laying. Also found several of our clingy friends attached to me after I got back inside!

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    Replies
    1. Yes, they like to hitchhike on us. They seem oblivious to substrate, perching on anything/everything. Good luck with that pawpaw!

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