Zebra Finch Females Avoided the Scent of Males with Greater Body Condition.

Simple Summary: Many animals use olfaction to assess potential partners or rivals. However, in the case of birds, the role of olfaction in assessing potential partners is still scarce. We performed a study to analyse whether Zebra Finch females use olfaction to detect male body condition. We used an olfactory chamber to offer females the scent of two males differing in body condition, and we recorded female choice. Our results show that females can detect the body condition of males, but contrary to what should be expected in a reproductive context, females chose the scent of males with a poorer body condition. Therefore, our results suggest that females performed their choice in a non-reproductive social context, avoiding potential conflict with males with better body condition. The role of chemical communication in the social relationships of birds is receiving growing attention, but our knowledge is still scarce compared to that of other taxa. Previous evidence suggests that chemical cues emitted by birds may carry information about their characteristics, which may be useful in the context of sexual selection. However, experimental studies are needed to investigate the role of bird chemical cues in signalling the quality of potential partners. We performed an experimental study aimed at disentangling whether the female Zebra Finches (Taeniopygia guttata), use chemical cues to assess the body condition of potential partners. We offered focal females (N = 28) the scent of two males differing in body condition (body mass/tarsus length ratio) (N = 28 scent donor males). Our results showed that females can assess the body condition of potential partners using olfaction. However, contrary to what should be expected in a mate choice context, females avoided the scent of males with greater body condition. Our results, therefore, suggest that, despite performing the study during the breeding period, social interactions may be mediating the avoidance of the scent of the male in better condition in this gregarious species, probably to avoid a conspecific competitor with better body condition. [ABSTRACT FROM AUTHOR]