Avian hormonal response (cort) to airport noise

Airport noise is known to generate stress and health issues in humans living around airports, but few studies have examined how birds are affected by such noise. It is possible that aircraft noise has similar effects to road noise, which has been shown to reduce reproductive success and to create barriers to avian communication. To evaluate whether birds living near airport lanes present higher stress levels than birds in natural habitats, we analysed corticosterone (CORT) levels in feathers in three airports (Brasília, Viracopos and Salvador) and three control-silent areas in Brazil. Birds were captured during the breeding periods of 2015 and 2016, when we collected tail feathers and took body measurements. We measured CORT levels in feathers after a methanol-based extraction, followed by an ELISA immunoassay. We extracted hormones from 821 individuals from 19 species and used GLMs to evaluate each species´ response. Rufous-browed Peppershrike (C. gujanensis), Lesser Elaenia (E. chiriquensis) and Suiriri Flycatcher (S. suiriri) presented significant increase of CORT levels in the airport areas. Plain-crested Elaenia (E. cristata), Swallow-tailed Hummingbird (E. macroura) and Southern House Wren (T. musculus) presented significant decreases of CORT levels in the airport area. The remaining species showed no significant differences. We are investigating whether species´ song frequency, sensitivity to urbanization, body condition, immune condition, and others variables may explain the diversity of patterns found.