They've spent the last 17 years underground, but now the sounds of a specific cicada group may once again fill the air across Long Island.

Cicadas are small bugs that can cause a big racket. Some say they are part of the sounds of summer.

"I haven't seen them yet this year," says Stan Trojanowski, of Bethpage. "I have seen them in the past."

Experts say the insects that only come out of the ground every few years could possibly re-emerge again.

"Fewer and fewercicadas come out every time," says Chris Simon, UConn professor of Ecology and Biology.

Simon has been studying cicadas on Long Island for decades. She says there are different groups of cicadas and one that is native to Long Island could come out this spring after not being seen for years.

Simon says the population has been declining for many different reasons. One reason she says is land clearing.

According to Simon, the last time this kind of cicada was seen was 17 years ago in Connetquot River State Park in Oakdale.

"It's one part of the ecosystem and when we start removing a piece here or piece there, the more pieces you remove the more the ecosystems decline," says Simon.

Experts say they want to keep track of the cicadas on Long Island. One way you can help is by using the free app called Cicada Safari. Take a picture or shoot a video and submit it through the app for scientists to view.

Simon says be on the lookout for the noisy bugs starting in late May.