Sierra Ru-Yi Glassman, Adi Domer, Adi Domer

Whereas vocal sexual dimorphism is widespread amongst birds, it has been historically overlooked in non-passerines such as hummingbirds. By evaluating correlations among sex, behaviors, and vocalizations, the meaning and utility of intentional sound production may be inferred. Anna's Hummingbirds (Calypte anna) exhibit pronounced sexual dimorphism, with males being larger and having more vibrant coloration than females, but vocal dimorphism in the species is unstudied. A common vocalization of Anna's Hummingbirds is the chip note, which is produced by both sexes in a wide array of contexts. Here, we correlated temporal parameters of chip notes with individual sex and behavioral contexts gathered from field observations and audio recordings. The production rate of chip notes differed significantly between male and female hummingbirds but did not vary much with behavioral context. Although Anna’s Hummingbirds produce chips across a broad spectrum of behaviors, dimorphic chip production may be important to territorial behavior.