Traffic noise reduces birds’ response to alarm calls

New research from The Condor: Ornithological Applications reveals that traffic noise can decrease the responsiveness to communication, especially alarm calls, in birds. The impact of this obstruction is essential, as alarm calls are meant to help birds avoid predators and other dangers they could come across.
Pollution can influence life in its many forms, obstructing our activities. Excess noise from different sources, among which traffic, can negatively influence animals trying to communicate. Due to the exposure to environmental noises, birds find it difficult to perceive alarm calls.
Researchers from New York’s Vassar College investigated the impact of traffic noise on birds’ responsiveness to alarm calls. As part of the research, the scientists employed speakers mounted near feeding platforms. They also planted bird seed in order to better capture the animals.
“Successful communication between a sender and a receiver is critical for coordinating behaviours between organisms. This coordination can be disturbed by anthropogenic noise, which has been shown to alter vocal signal production in many species of birds. In addition to affecting senders, noise may also alter reception and behavioural response,” noted the research abstract.
The team used three different recordings: alarm calls, traffic noise, and a combination of these two. When used alone, traffic noise did not interfere with the birds’ feeding process. However, five times more birds came to eat when the researchers used the alarm calls alone, compared to traffic noise.