INDIANAPOLIS — Humming, buzzing and whirring like high-pitched tiny buzz saws, a specific brood of cicadas is latching onto Indiana trees four years earlier than expected, a leading expert on the insects says.
“What we're experiencing right now is a four-year acceleration of Brood X, which was expected in 2021,” said Gene Kritsky, dean of the school of behavioral and natural sciences at Mount St. Joseph University in Cincinnati. "We've seen these accelerations before, but usually they don't come out in numbers large enough to sing and make noises and mate and reproduce."
In 1991, Kritsky's students were digging up cicadas. "We found they were growing faster than they were expected to be," said Kritsky.
Kritsky, a graduate of Indiana University, receives Indiana reports of cicada "emergences” and compiles a map of their whereabouts. His chart currently includes Indiana (excluding the northwest part of the state), Kentucky, Ohio, Tennessee, Pennsylvania, Maryland and Virginia.
Others say the presence of the demonic looking Brood X (called Brood 10) cicadas is all part of the short life above ground for the pesky but generally harmless insects.
"Brood X is supposed to come out here in Indiana in some of the areas this time of year. They're just called stragglers," said Indiana State Entomologist Megan Abraham.
The big cycle for this brood is still coming in 2021, she said. "They're doing what they're supposed to be doing."
The billions hatching this season may be around for six weeks, possibly through the end of June before mating and dying.
Botanist Bill McKnight was working in his northeast side Indianapolis arbor in late May when he heard cicadas singing and noticed a red-eyed insect on the lumber. He called Kritsky who told him there was a strong presence of cicadas being reported near Fort Benjamin Harrison. But there may not be a strong enough prevalence to cause alarm.
"Unless there's a large enough number, there's a less likely chance of there being a new brood because they'll all get eaten." said McKnight, who is the author of "The Rantings of a Mad Botanist."
"Cats, dogs, pigs, squirrels will eat them, birds eat them. When a regular emergence happens, they're in such huge numbers that they actually overwhelm the predators," he said. "Predators just can't eat anymore and that's their strategy for success because they're certainly not hiding."
Other broods have also been noted earlier than expected and in other parts of the country, he said. Though not verified, the reasons for the early emergence may be due to the warming of the Earth or the shifting of some species of trees to the north and west, Kritsky said.
Last month, Purdue University professor Songlin Fei reported that over the past 30 years 86 species of trees in the eastern part of the U.S. had shifted in response to climate change. Deciduous trees like oak and maple are primarily moving westward and evergreens are moving to the north, Fei said.
Cicadas feed on the roots of trees, said Kritsky who documented the presence of cicadas in America back to the 1600s in his book "Periodical Cicadas: The Plague and the Puzzle," published by the Indiana Academy of Science.
"The only phenomenon that's affecting the cicadas right now is the increase in temperatures," Kritsky said. 'If temperatures are affecting the trees, they're also possibly affecting the cicadas."
State Entomologist Abraham attributed the Brood X presence to a genetic variation much like humans have different eye colors. She said, "Some people like to point to perhaps global warming or some kind of climate event, but that's just not part of what this is."
Most broods appear once every 17 years. Two broods come out every 13 years.
The male cicada makes the screeching noises by vibrating membranes on the underside of the abdomen. Females can’t make the sound but they lay eggs that develop into nymphs. They eventually climb out of the ground and crawl up posts or tree trunks and shed their shell, becoming winged cicadas. They mate and live about a month.
They can damage young trees, Kritsky said.
But for the most part, cicadas are merely a nuisance. The infestation is not enough to spark a flurry of phone calls from tree owners to area nurseries.
“I’ve been expecting people to start calling because I keep hearing them at my house and saying, 'Oh, it’s going to start,'” said Scott Bardash at Allisonville Nursery in Fishers. “I’ve been waiting for the first one.”
If customers did call, Bardash would tell them to not worry.
“They eat a little bit of stuff off the trees but it’s not going to kill the trees,” he said. “It’s not anything to be concerned about.”