LANDSCAPE FEATURES ASSOCIATED WITH BEHAVIORAL CHANGES ALONG AN URBAN-RURAL GRADIENT IN SONG SPARROWS
Organisms in urban habitats often display traits that differ from rural counterparts. Studies of song sparrows (Melospiza melodia) have found differences in behavior between urban and rural populations, with urban males showing higher territorial aggression and higher boldness than rural males. However, previous studies have simply categorized landscapes as either urban or rural, rather than quantifying landscape differences for each song sparrow territory, and thus, it is unclear what changes to the landscape influence behavior and result in urban animals being more aggressive and bold. In this study, we used playbacks of heterospecific Carolina wren (Thryothorus ludovicianus) alarm calls to measure boldness in song sparrows. For each territory, we also measured several landscape variables that correlate with urban disturbance, such as human population density, amount of built space, and distance to buildings. We performed regression analyses in order to determine which landscape variables best correlate with variation in behavior. Our results indicate that distance to the nearest building is the best predictor of behavior, with bolder birds living closer to buildings. These results suggest that the boldness typical of urban birds can arise in birds in close proximity to human activity, even when their territories are found in an otherwise non-developed, rural landscape.
Wisher, Kaley and Hyman, Jeremy
"LANDSCAPE FEATURES ASSOCIATED WITH BEHAVIORAL CHANGES ALONG AN URBAN-RURAL GRADIENT IN SONG SPARROWS,"
Georgia Journal of Science, Vol. 75, No. 1, Article 51.
Available at: https://digitalcommons.gaacademy.org/gjs/vol75/iss1/51