Meeting Abstract
Anthropogenic noise negatively impacts acoustic signals in a variety of animals. Recent research has shown that birds can reduce signal masking by adjusting acoustic parameters of their sexual signals (songs) in noisy environments, but we know little about other types of vocalizations. Masking of other types of vocalizations, like anti-predator signals, could have major fitness consequences. We investigated whether traffic noise impacts avian alarm call production or perception with a combination of lab and field experiments in great tits (Parus major), a common songbird that frequently inhabits noise-polluted environments. In response to experimental noise manipulation in controlled laboratory conditions, great tits increased the amplitude, but not frequency parameters, of their calls. Playback experiments conducted in the wild indicate that traffic noise masks alarm calls, impeding great tit perception of these signals. Thus, despite the vocal adjustments used to compensate for anthropogenic noise, great tits are not able to overcome the challenges posed by even moderately noisy environments.