Meeting Abstract
While many common songbird species use human-modified environments, the potential implications for many of these species are not well understood. Urban stressors such as reduced habitat area; high levels of light and noise; introduced competitors and predators; and limited natural food resources can result in heightened stress responses over time. While corticosterone (CORT) plays an important role in normal metabolic functions and in allowing an organism to respond to immediate threats, sustained elevated CORT levels can negatively impact an individual’s health and fitness. We selected a common songbird, the American Goldfinch (Spinus tristis) as a model organism, and collected blood samples from individuals in urban and rural settings during winter and early spring 2016. CORT levels were analyzed from samples taken immediately and 30 minutes after capture, to assess both baseline and induced CORT responses. Initial analyses revealed no difference in baseline CORT levels between individuals using urban and rural environments, though rural birds displayed a somewhat stronger induced CORT response than did their urban counterparts. These results suggest that for S. tristis, the stressors of urban development are negligible, or trade off with benefits of cities such as predictable food supplementation.
