STICKNEY, Ill. (CBS) — Some neighbors complained recently about sounds resembling gunfire interrupting the silence at the Stickney wastewater treatment plant near Midway International Airport.

But it was not gunfire.

LISTEN: WBBM Newsradio’s Steve Miller reports

As WBBM Newsradio’s Steve Miller reports, the sounds actually came from Craig Bloomquist, a wildlife biologist with the U.S. Department of Agriculture. He was setting off pyrotechnics at the Stickney Water Reclamation Plant, and along the Chicago Sanitary and Ship Canal.

The purpose is to keep the geese out of Midway’s flight path.

“When it’s really cold and everything else freezes up, this is the last body of water to freeze up near Midway,” Bloomquist said.

Bloomquist says the pyrotechnics are working. He says the geese are going elsewhere.

But also, he says, this winter is much tamer than last so geese don’t have to go to the warmer waters around the Stickney plant. That means less work for him.

“Less work like this,” he said. “There’s always something to be addressed at Midway.”

Right now at Midway Airport itself, Bloomquist says red-tailed hawks and snowy owls are the concern.