Meeting Abstract
Behavior that is consistent within individuals but variable across and between populations, or personality, may have important ecological and evolutionary implications. As part of our research program on hybridization between black-capped and Carolina chickadees in southeastern Pennsylvania, we seek to understand whether personality variation can influence the extent and patterns of interbreeding. In this study, we investigated patterns of variation in boldness and exploratory behavior both within and between the two species. We measured boldness of breeding pairs by their vocal and spatial responses to simulated predator threats at active nests. In addition to considerable intraspecific variation, Carolina chickadees gave more scolding calls with more dee notes (an indication of their perception of threat) but attacked decoys less vigorously than did black-capped pairs. To measure exploratory behavior, we observed individuals inside a portable aviary deployed at our field sites. Composite scores of exploratory behavior, calculated using principal components analysis, were highly repeatable within individuals while averaging higher for Carolina than black-capped chickadees. These results suggest that potential exists for personality variation to influence hybridization through effects on social interaction and mate choice in mixed populations. Work in progress asks whether personality correlates with intraspecific and interspecific variation in DRD4 genotypes.
