Meeting Abstract
Social behaviors play a role in shaping the diversity and composition of an animal’s bacterial communities. Sexual activity, in terms of copulations, is one way through which bacteria can be transmitted socially between individuals. While considerable research has focused on the sexual activity or the microbiomes of animals, little research has focused on the intersection of the two. Here, we experimentally assessed how female sexual activity influences the cloacal microbiome of female tree swallows, Tachycineta bicolor. We administered estradiol, ATD (1,4,6-Androstatriene-3,17-dione), and control implants to female tree swallows at the beginning of the breeding season. Manipulation of hormonal activity via estradiol and ATD implants has been well established as an experimental method to increase and decrease sexual activity in female birds, respectively. Then, we assigned parentage of nestlings (a proxy for sexual activity) to determine the minimum number of sexual partners per female. We collected cloacal swabs from experimental females during incubation and subsequently used 16S rRNA gene amplicon sequencing to characterize each females’ cloacal microbiome. Additionally, we collected body condition and fitness metrics, such as female mass and reproductive success, to determine if there were negative repercussions of potentially pathogenic cloacal bacteria. This study will broaden our understanding of how sexual activity plays a role in shaping the cloacal microbiomes of wild birds. By understanding how bacterial communities are shaped we can begin to untangle the potential tradeoffs associated with alternative behavioral strategies.
