Where will the cicadas emerge? ‘Trillions’ of cicadas from 2 broods will appear this year in rare biological event

WASHINGTON (DC News Now) — Thousands across the DMV and millions around the nation gathered to watch the solar eclipse on Monday — but that isn’t the only rare scientific occurrence this year.

In fact, one other event happening in 2024 hasn’t happened since 1803.

In the next two months, two large broods of cicadas — Brood XIX and XIII — will co-emerge in parts of the U.S.

“The last time it happened was then Thomas Jefferson was president, so that was a while ago … It’s a life event,” said University of Maryland Professor Paula Shrewsbury.

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These are both types of periodical cicadas, which spend most of their lives buried underground in larval form. Depending on the species, they emerge every 13 or 17 years.

Brood XIX, which is a 13-year cicada, is also known as the “Great Southern Brood.” According to the University of Connecticut, it is possibly the largest periodical cicada brood.

Some of this brood will emerge in the DMV — Shrewsbury said these cicadas are present in St. Mary’s County in Maryland and parts of Virginia such as Alexandria and Stafford County.

Brood XIII — a 17-year cicada — will not be visible in this area. It’s also known as the “Northern Illinois Brood.”

“I think we are truly going to see trillions of cicadas active out there,” Shrewsbury said.

With all of these cicadas set to emerge, what can we actually expect to see? Here in the DMV, there won’t be too many periodical cicadas hatching this summer. Shrewsbury said that there may be some overlap in central Illinois and part of Iowa.

If you’re traveling to try to glimpse “cicada-geddon,” as some online are calling it, experts said to temper your expectations — the University of Connecticut said the two broods are adjacent and have very little, if any, geographical overlap. Shrewsbury said that the two broods also look the same if you’re just out and observing them.

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Shrewsbury said that cicadas in Southern states will likely emerge first due to warmer temperatures. She said to expect them to start hatching towards the end of April or the beginning of May. Brood XIII will likely emerge in mid-late May.

University of Maryland Professor Emeritus Michael Raupp runs a blog called Bug of the Week — and in his post Monday, he talked about this once-in-a-lifetime occurrence.

He looked at a study that looked at cicada emergence in 2020 to reflect on when 2024’s two broods may appear.

“If 2024 is anything like 2020, outliers will appear in April, but the great cicada tsunami hits the last two weeks of May. By Memorial Day weekend the cicadapalooza will be rocking the treetops in 18 states around the country,” Raupp said in his blog post.

Right now, Virginia residents may notice dime-sized holes in the ground. Shrewsbury said that these holes signify that cicadas are getting ready to emerge — they will burrow up and peek out before burrowing back down to prepare for their appearance.

Shrewsbury said that you also might notice increased animal activity or signs of digging — animals like foxes, raccoons and skunks eat cicadas, so they will dig at the ground to unearth larvae for a cicada-tastic feast.

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Shrewsbury said that these appearances of periodical cicadas are exclusive to the eastern part of North America — no other part of the world sees broods of this size appear in patterns like this.

The University of Connecticut said that this is the first time since 2015 that a 13-year brood and 17-year brood are emerging in the same year. It’s also the first time since 1998 that adjacent 13 and 17-year broods will emerge in the same year.

2024 is the last time that all seven named periodical cicada species will emerge as adults in the same year until 2037.

The last brood of periodical cicadas to emerge in Maryland was Brood X in 2021. Brood XIV will be emerging in the area in 2025, but it is a smaller brood than Brood X.

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