Meeting Abstract

P1.21  Saturday, Jan. 4 15:30  Corticosterone Levels and Urbanization Effects on Flight Initiation in Song Sparrows (Melospiza melodia) and Northern Cardinals (Cardinalis cardinalis) BATTLE, K.E.*; FOLTZ, S.; MOORE, I.T.; Virginia Tech, Blacksburg; Virginia Tech, Blacksburg; Virginia Tech, Blacksburg keb8392@vt.edu

Urbanization can impact fauna by altering their behavioral responses to human presence and activity. Certain traits such as boldness or habituation to humans may be favored to enable their coping with urban challenges. Such traits are components of and characterize an individual’s “behavioral syndrome,” which likely has physiological control mechanisms. We sought to understand how the urban environment may affect or select for boldness and habituation traits in male Song Sparrows (Melospiza melodia) and Northern Cardinals (Cardinalis cardinalis). For sparrows, we measured flight initiation distance (FID; distance at which birds initiated flight when approached by a single observer) as well as corticosterone levels and territorial aggression. For cardinals, we measured only FID. For both species, urban birds allowed a closer approach than did rural birds. Within both urban and rural habitats, sparrows allowed a closer approach than did cardinals. Results not only reinforce previous findings that urban birds are more habituated to humans but also demonstrate significant differences in behavioral syndromes across species. Comparing these results with endogenous corticosterone levels and aggression scores will further our understanding of the mechanisms underlying urban adaptations in fauna.