SEWALL, K.*; HAHN, T. P.; University of California, Davis; University of California, Davis: Social Experience Influences Behavioral Discrimination of Call Types in Red Crossbills

Red crossbills are songbirds that produce discrete, group specific calls, and call type is correlated with specific morphologies and foraging preferences. To examine the influence of these distinct call types on social group formation, I conducted a series of playback studies to quantify the specificity of vocal responses of birds upon hearing calls of their own type compared to a different type. Specifically, a group of 32 wild-caught, adult crossbills were exposed to recordings of two different types of flight calls soon after capture and again after being housed either with a social companion of the same call type, or a different call type, for 4 months. The number of response calls each bird produced during each recording was quantified and the proportion of total calls given in response to each category of call was calculated. The playback study conducted soon after capture revealed that crossbills produce a greater proportion of calls during playbacks of their own call type compared to playbacks of birds of a different type. However, the second playback study demonstrated that the observed behavioral discrimination between recordings of different call types was flexible: birds housed with companions of their same call type continued to call more to recordings of their own call type, but birds housed with companions of a different call type no longer discriminated between recordings of their own versus a different type. Collectively, these data suggest that social experience influences behavioral discrimination between call types in red crossbills.