Listen: Cicada Choruses Sweep Central Maryland
NATHAN STERNER, HOST: Brood X cicadas have begun to emerge in central Maryland. The insects appear every 17 years... and this summer, they’re expected to be with us through the 4th of July. WYPR’s Emily Sullivan has this audio postcard from a cicada hunt with Dr. Mike Raupp.
EMILY SULLIVAN, BYLINE: It’s a sunny afternoon in Columbia...and brood X cicadas are singing louder than the airplanes overhead.
MIKE RAUPP: It's almost to the point where I didn't love cicadas quite so much, I'd be shrieking and running away. I'm guessing there are literally tens of thousands of cicadas in these treetops right now.
SULLIVAN: That’s Dr. Mike Raupp -- a professor of entomology at the University of Maryland and self-described cicada enthusiast.
RAUPP: They're not going to bite. They're not going to sting. They're not going to carry away dogs and small children like the monkeys in The Wizard of Oz. These are harmless creatures.
SULLIVAN: The emergence of Brood X, also called Brood 10, kicked off in March, when cicada nymphs began to emerge from exit holes. Raupp kneels down before a large oak tree to scope some out.
RAUPP: I’m excavating here. I'm moving the dirt away now so we can actually see how many holes were really, really here…
SULLIVAN: Cicadas have lived in these little burrows for just under 17 years, growing and molting...and drinking fluids from tree roots. Then, weeks ago, when the soil temperature hit JUST about 64 degrees, cicada nymphs excavated their homes and used their tiny claws to crawl about a foot up to the surface of the earth. Raupp counts the exit holes in the square foot of dirt he’s cleared.
RAUPP: ...28, 29, 30. If there are 30 holes per square foot underneath this tree, that's going to translate into about one point two million cicadas per acre. That's why we're saying that during the emergence of Brood 10, which is going to be found in 15 states, that there could be billions or perhaps even trillions of periodical cicadas up and out of the ground this year.
SULLIVAN: Once the cicada nymphs have emerged from their burrows, they have a task at hand: molt out of one last exoskeleton.
RAUPP: They will make their way to vertical structures. It could be a tree. It could be a shrub. Or when I come out at nighttime, if I stand still long enough, it could be me.
SULLIVAN: They attach to these structures with their claws...and pulse their way out of the sap-colored exoskeleton. Then, they have five to six weeks left to live..and one goal: romance. They’ll mate as many times as possible before they die. Their famous cacophony is part of their mating ritual.
RAUPP: The males are using their timbal organ to create this sound. Once they get eyeball to eyeball in the treetops, the males will then switch over to courtship songs and try to convince that special someone that she should be the mother of his nymphs. So right now, there's some wicked sex going on up there.
SULLIVAN: That timbal organ is a little white membrane that acts like a drum head. The abdomen of the male cicada is hollow — it acts as a reverberation chamber to amplify the sound created by the timbal. Sounds like this one: the courtship song of the male septendecim. Listen closely to hear why they’re often called the Pharaoh cicada.
— PHARAOH CICADA MALE MATING CALLS —
RAUPP: A lot of people think that that call is kind of like, “PHAR-OAH. PHAR-OAH”
SULLIVAN: If a female cicada is swayed by this sweet song, she’ll mate with the male. She can lay about 20 to 30 eggs at a time and up to 600 during the course of her life. Raupp says it can be hard to tell cicada species apart, but you don’t need a PHD to tell males from females.
RAUPP: You can tell this is a female cicada. If we flip her over and look at the tip of her abdomen, we can see this pointed appendage. This is her ovipositor. That's what she'll use to cut slices in branches and deposit eggs in those slits.
SULLIVAN: Those eggs are usually laid in the tips of small tree branches. They take somewhere between 6 to 10 weeks to hatch as nymphs the size of a grain of rice. Those nymphs drop to the surface of the earth, where they burrow and begin their nearly 17 years underground. Raupp says, the strange life cycle of Brood X cicadas are actually a huge advantage — they appear so infrequently that predators learn not to rely on them as a steady food source.
RAUPP: It's amazingly clever, you know, to simply outlive your predators so they can't track you through time and then to emerge in such massive numbers that you simply overwhelm them. Pretty bizarre. Pretty clever.
SULLIVAN: He says those massive numbers are another evolutionary advantage.
RAUPP: It's an amazing, fantastic evolutionary adaptation, unique, pretty much unique to the insect world.
SULLIVAN: After decades of studying cicadas, Raupp is very fond of them. But even he’s blown away by the amount of hype that surrounds the insects this year. He suspects the pandemic may have something to do with it.
RAUPP: Cicadas have been living underground in the dark and they do social distance underground -- they don't compete for root space. And then in the 17th year, the teenagers are going to come up. They're going to shed their earthly mask. They're going to climb into the treetops. They're teenagers! So they're going to have lots of music and romance and they're going to rock it now.
SULLIVAN: It’s hard not to see the analogy.
RAUPP: So we've got vaccines. We're taking off our masks. What's the first thing we do? We go to concerts. We get outside with our fellow human beings, and we're going to listen to music and party.
SULLIVAN: But Raupp knows that not everyone has suddenly found the cicadas relatable. He says wedding planners started to reach out to him in the winter, asking when they’d be least likely to crash an outdoor wedding.
RAUPP: I said, well, look, shoot for Memorial Day weekend and that way you'll have 100 surprise visitors at that wedding will make it ever so much more memorable.
SULLIVAN: He also gets asked on how to cope with disgust and fear. He suggests learning about how harmless they are. But if you pick up a fully matured male, he might scream….like this cassini cicada.
— CASSINI CICADA MALE ALARM CALLS —
RAUPP: That's his alarm call, also called the Squawk Call. This is the sound they make when a bird or maybe a bug grabs one, trying to convince them that they’re not really good to eat. ‘I'm noisy and nasty. Let me go. Let me go. Let me go!’
SULLIVAN: For those who are enjoying the visitors and want to see even more of them, Raupp says now is their peak.
RAUPP: This will crescendo for the next week or two. They'll still be emerging the first week of June, but then emergence will stop and we'll begin to see the die off. So by the Fourth of July, it's all going to be over, sadly. 17 years, a brief moment in the sun and boom, you're gone.
SULLIVAN Gone until 2038, that is. I’m Emily Sullivan, reporting for 88-1 WYPR.