Expect to hear the chirping of some cicadas in the next week when a portion of the 17-year brood might appear a year early.
Since only a small fraction of the cicada brood could emerge, they will likely all be eaten by predators before they’re able to mate.
But it could mean the chirping of cicadas this year will be louder when the periodic cicadas overlap with the yearly cicadas that emerge a little later in the season.
“It’s not expected to be in very large numbers, these off-year ones,” said Kacie Athey, assistant professor at the University of Illinois Urbana-Champaign who studies how insects affect agriculture.
Although it’s unclear why some cicadas show up a year early, it’s a common phenomenon, Athey said.
Early cicadas are paradoxically called “stragglers.”
Next year is expected to be a big moment for cicadas. Two major broods — a 17-year group and 13-year group — are expected to emerge when the underground soil warms to about 64 degrees in mid-May.
That, in combination with the typical yearly cicadas and the early cicadas from the 2028 brood, could overwhelm agriculture in the Midwest.
“Because they come out in such large numbers, it can be devastating to young trees,” Athey said. “Our whole state will see an emergence of these two broods. It could be a big year for cicadas.”
Yearly cicadas are larger with greenish-blue bodies.
Cicadas live for four to six weeks after showing themselves. That’s enough time for them to make some noise, mate, lay some eggs and die — beginning the cycle again.
The 17-year brood, which will emerge in northern Illinois, is the world’s longest-living insect.
“They’re super cool and strange creatures, given their longevity underground,” Athey said. “They come aboveground and don’t eat. They just mate and die. We only see a tiny piece of its lifecycle.”
The batch last emerged in 2007 and laid offspring that have been burrowed underground for the past 16 years. In 2020, a portion of them showed up four years early — another common timeframe that stragglers appear.
Cicadas do not hibernate but burrow underground and survive off tree root sap.
“They’re in such large numbers, it’s amazing they don’t cause issues in that underground world. They’re an example that there’s so much hidden diversity in the world. And we don’t think about them often.”
Homeowners don’t have anything to worry about, Athey said, besides some chirping.