"They" would be cicadas, the big, noisy bugs that climb out of the earth about every decade and a half to make everyone's life more exciting.
Experts tell Gannett News Service that the bugs live underground and feed off fluid that gathers near the roots of plants, then emerge from the soil when its temperature reaches 64 degrees.
They're largely harmless, but their sheer numbers can cause headaches. Some areas could see as many as a billion of the cicadas per square mile. That can lead to a lot of dead bugs all over roadways and grassy surfaces. They can also disrupt outdoor events with their loud buzzing.
New York radio station WNYC is helping to track the invasion.