Variation in Note Composition of Chick‐a‐dee Calls is Associated with Signaler Flight in Carolina Chickadees, Poecile carolinensis

Chick‐a‐dee calls are used in a wide range of social contexts in Poecile (chickadee) species. These calls comprise a number of distinct note types. Earlier naturalistic observational studies suggested that the ‘C’ note type was used frequently in calls of Carolina chickadees ( P. carolinensis ) in the context of flight. We conducted three field studies with Carolina chickadees to test in more experimentally manipulative ways whether Chick‐a‐dee calls with more ‘C’ notes were associated with flight. The three studies differed in how they elicited flight behavior from chickadees, as well as in the likely arousal levels experienced by the birds. First, we captured chickadees and released them, recording any calls they produced in flight or when later perched after escape. Second, we approached chickadees that were foraging near the ground in field settings and recorded any calls they produced when perched compared to when they were in flight. Third, from a distant blind, we recorded chickadees flying to and from feeding stations, in which the closest perching substrate/cover was at least 2 m away from the feeding station, thus requiring flight. In all three studies, calls contained more ‘C’ notes when birds were in flight compared to when they were perched. This work expands our understanding of variation in note composition of chick‐a‐dee calls beyond the contexts of food and predator detection to the context of movement. Studies are now needed to test whether such variation in chick‐a‐dee calls brings about group cohesion.