ITHACA — Media reports have been buzzing about the “Brood X” cicada emergence, which will send millions of the buggers out of the ground after 17 years spent there.
A “brood” is a geographically distinct emergence involving great numbers of cicadas. Northern New York is pretty far removed from the Brood X emergence areas.
“In the long-term evolution of cicadas, they have adapted to emerging in great numbers in prime years — that is every 17 years, or every 13 years or 11 years,” said Jody L. Gangloff-Kaufman, senior extension associate for Cornell’s department of entomology.
The last time the massive Brood X (Roman numeral 10) emerged was in 2004.
“Scientists went looking for those cicadas on Long Island in 2004 and could not find them,” Ms. Gangloff-Kaufman said. “So we believe they are locally extinct. That’s pretty much the only place in New York that people have found them in 100 years.”
Trees, Ms. Gangloff-Kaufman said, do something similar to the life cycle of cicada broods.
“They do masting,” she said. “One year, you’ll get very few acorns and maybe three years later you’ll get more acorns than you’ve ever seen in your life. It’s a biological strategy to overcome predation, so at least some of your progeny will survive.”
The geographically distinct vast emergence of cicadas in New York state involve different broods. Brood VII, the “Onondaga brood” is closest to Northern New York.
“There’s a healthy brood in the Syracuse area that will emerge in 2035,” Ms. Gangloff-Kaufman said. “We’re going to be waiting a bit. The last time we had a real good emergence was a while ago. It’s not a very-often phenomena. That’s why there are cicada tourists.”
The Brood X insects spent 17 years underground. They have begun to emerge from Georgia to Pennsylvania and west to the Mississippi. Scientists say there can be up to 1.5 million cicadas per acre in some areas.
The insects emerging, Ms. Gangloff-Kaufman said, will leave shells behind.
“That’s the last molt of the nymph of a cicada,” Ms. Gangloff-Kaufman said. “They live underground in that shape feeding on the roots of trees.”
But development can effect the broods.
“Seventeen years is a long time,” Ms. Gangloff-Kaufman said. “A lot of land can get cleared in that period of time, especially in the last 30 years. When you remove the trees and build a house, all those cicadas underground are dying because they no longer have food.”
Soil temperatures must reach the mid-60s before cicadas emerge. The annual ones that emerge and take up residences in trees in Northern New York in late summer — and not linked to broods — are a different species from the ones in Brood X.
“Our normal cicadas are called Dog-Day cicadas,” Ms. Gangloff-Kaufman said.
The males of the species have a distinct high-pitched call to attract females.
“The scream that these periodical cicadas make is much more intense,” Ms. Gangloff-Kaufman said. “From the recordings I can hear, it sounds pretty unpleasant.”