The cicadas are coming! US prepares for plague that happens once every 17 years

Periodical cicadas, large insects indigenous to the eastern US, spend most of their lives underground

A newly emerged adult cicada dries its wings on a tree in Arlington, Virginia. Reuters

Alison Scharman still remembers when cicadas took over her world.

The 30-year-old consultant was in middle school in Bethesda, Maryland, just outside Washington, in 2004, when the cicadas last invaded the eastern US.

“It was a pretty crazy experience,” she said. “They were everywhere and the middle-school boys would chase them around and catch them and dare each other to eat them.”

Periodical cicadas are large insects indigenous to the eastern US that spend most of their lives underground.

“They’re not hibernating, they’re not dormant, they’re just developing. They're growing underground,” said John Lill, chairman of the biology department at George Washington University in Washington, DC.

Every 13 or 17 years, billions of cicadas emerge from the earth. Their brief lives above ground are singularly focused on finding a mate.

"Over the last couple of million years, the cicadas have split into several geographically temporarily isolated groups of individuals that emerge on different schedules," Prof Lill said.

Brood X, which is expected to emerge in late April and the end of May, is one of the largest groups.

"It's going to be a big show," an excited Prof Lill told The National.

Cicadas will storm several areas in up to 15 different states. But the nation’s capital will be the epicentre.

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Washington "is about as dense as it gets”, Prof Lill said. “We’re pretty much in ground zero for one of the most numerically abundant broods as well as the densest broods of periodical cicadas in existence."

In many neighbourhoods across Washington and the surrounding suburbs, it will be impossible to ignore the screaming insects.

Male cicadas produce a mating song that sounds like something between an incoming helicopter and TV static. “It is one of the loudest sounds produced by any insect. It’s in the 80 to 100-decibel range, the sound of a jet plane,” Prof Lill said.

The last time cicadas descended upon the capital, former president George W Bush was gearing up for a second run at the White House, the Boston Red Sox were still suffering through their 86-year baseball curse and Facebook was just two months old.

But for those who were in the area, it was a memorable time.

“It wasn’t like, oh, we’re just living life and there are some bugs. It’s like a plague,” said Ms Scharman. It’s like a biblical plague, the numbers that they come in.”

And that is actually how the early US colonists described them. But Prof Lill is quick to point out cicadas are not locusts and pose no dangers to human beings or crops.

A hole created by a cicada in Professor John Lill's backyard. Cicada's pre-dig the tunnels from which the emerge. Courtesy of John Lill

“They are totally harmless. They don’t bite, they don't sting, they don’t really do anything to people other than just make a lot of noise.”

What they do become is a giant source of food for thousands of other animals, including birds and dogs.

“If you do have pets, you want to try to minimise how much they consume,” said Prof Lill, because, for example, dogs can become constipated if they eat too many.

Humans can eat them, too. Prof Lill said in 2004 some restaurants around Washington served them up to customers.

The insects are not immune to global warming, and biologists say it may be forcing 17-year cicadas into a shorter, 13-year cycle.

In 2017, some of Brood X emerged in the southern fringes of cicada territory.

“What is going to potentially happen is, as it spreads north, you might see an increase in 13-year broods and a decrease in 17-year broods,” Prof Lill said.

Entomophiles will be able to follow Brood X through an app developed by Mount St Joseph’s University in Cincinnati, Ohio. Users will be able to track where cicadas are spotted and upload their own photos of sightings.

Ms Scharman is looking forward to seeing reality lives up to her memory of the cicadas.

“I hope that they are what I remember them being like, just so that my friends can see them,” she said.