Are male meadow voles (Microtus pennsylvanicus) influenced by social odor context with regard to scent marking behaviors?

Meadow voles (Microtus pennsylvanicus) rely on olfactory communication, such as scent marking, to find and secure mating opportunities during the breeding season. Scent marks, and odors in general, provide information about the donors and persist in the environment for extended periods, allowing a wide audience. Whether a vole responds to another scent mark(s), or odor(s), depends on the social context and the information the odor provides about the donor(s). Therefore, we examined if male scent marking toward a social odor or female meadow voles is influenced by information present or previously encountered based on contextual differences in the social odor. We presented males with two odor associations of a male with a female with contextual differences in the age of the rival. We tested male scent marking under two conditions: one with two social odors present, current information, and a second with the females present from previously encountered social information, prior information. It was found that rival male age did not affect the scent marking behavior of males toward a social odor or female voles. Rival male age also did not affect preference as males did not show a preference for either female. The lack of an effect may lie in the properties of scent marks and the natural history of meadow voles during the breeding season. The odor of an individual rival may not represent a strong enough competitive threat to influence a signaler's decisions, but the association could still provide the signaler with valuable information about which females are considered high quality. [ABSTRACT FROM AUTHOR]