From DNA Info:
Commuters at a subway station in Queens are now being greeted with more than just the sounds of a rumbling train.
The MTA is using recordings of "predatory bird calls," at the 52nd Street station in Woodside, one tactic in a multi-faceted $250,000 effort to keep pigeons from roosting — and pooping — there.
The feature was installed at the station earlier this month, an MTA spokeswoman said and the Sunnyside Post first reported.
The squawking, shrieking and chirping sounds are meant to mimic birds of prey, like a hawk, and are played randomly through small speakers underneath the station.