Kevin Ortiz, a spokesman for the Metropolitan Transportation Authority, said the agency contracted California firm Bird-B-Gone to install the $375 system at the Roosevelt Island subway station in December and officials have since seen "a noticeable decrease in birds and droppings," The New York Times reported Monday.
The system pumps pigeon distress calls and predator sounds through the facility every 2 to 10 minutes to discourage pigeons from making the station their home.
Some subway riders said they have not noticed a decrease in the pigeon presence.
"The bird scare noises annoy me more [than the pigeons]," rider John McCormick said.
Notable deaths of 2014 [PHOTOS]