Meeting Abstract
Human-made noise is globally pervasive and degrades environments by disrupting organisms’ abilities to interact with their environment acoustically. Although many species are now known to avoid noisy areas, data on whether those that remain in noise-polluted areas suffer physiological and fitness consequences are sparse. We used a unique study system in the natural gas fields of NW New Mexico, where anthropogenic noise is isolated from most variables associated with human activity, to understand how noise exposure influences stress physiology and reproductive success in three cavity-nesting birds. Across all species, we found noise to negatively influence baseline corticosterone concentrations in adults and nestlings and noise to positively effect stressor-induced corticosterone in nestlings. We also found noise to negatively effect fitness in two ways. In the noise-tolerant Western Bluebird elevated noise resulted in reduced hatching success. For all three species, nestling feather growth and body size showed a non-linear response to noise levels with accelerated growth in feathers and body size at intermediate noise levels. Our results are consistent with conservation concerns that noise exposure can negatively impact fitness. Additionally, our findings demonstrate that noise represents a chronic, inescapable stressor that causes glucocorticoid dysfunction in a manner consistent with responses to psychological stress in laboratory studies. Given that anthropogenic noise is ubiquitous, it is probable that many other species suffer similar physiological and reproductive consequences of noise exposure.
