Meeting Abstract
Animal personality, behavior consistent within but variable among individuals, influences evolution in both predictable and changing environments. Our research program focuses on interactions between black-capped and Carolina chickadees in southeastern Pennsylvania where their ranges overlap in a hybrid zone. As climate change drives the hybrid zone northward, understanding the species’ response mechanisms to change becomes increasingly important. In this study, we investigated boldness behavior in pure and mixed populations of Black-capped and Carolina chickadees. To measure boldness response, we used a motorized woodpecker decoy as a simulated threat at active nests. Most assays elicited a pair response, while video recordings provided individual-level behavioral measures. Preliminary analysis indicates that in terms of latency to make the first ‘chick a dee’ alarm call and total call rate, pairs in all populations behaved similarly; however, black-capped chickadees gave fewer dee notes (less intense response) than chickadees from Carolina or hybrid-zone populations. A secondary focus of this study is how variation in a personality-related gene, DRD4, contributes to these differences in boldness response. Prior work in our lab indicates that a single nucleotide polymorphism in DRD4 exists in different frequencies between Carolina and Black-capped populations. Work in progress aims to determine whether a relationship exists between boldness response and DRD4 genotype.
