Road Ecology Center

Highway noise can mask vocal communication and natural sounds important to wildlife for mate attraction, social cohesion, predator avoidance, prey detection, navigation, and other basic behaviors. This acoustic interference can potentially result in the reduced ability of individuals to acquire mates successfully, reproduce, raise young, and avoid predation. Because different species have evolved unique vocal repertoires, they are differentially susceptible to the masking effects of highway noise. No single noise-level criteria can be used to accurately define impact thresholds for all species. Here we show the utility of using bioacoustic profiles of bird vocal signals to identify and describe the range and variability of acoustic-masking thresholds. Variation in noise load, source amplitude, and signal frequency are modeled to illustrate the dynamic nature of each species’ critical acoustic space.