Relatively little is known about the mechanisms of communication during the non-breeding season in species that are seasonal breeders. Previous work with meadow voles, Microtus pennsylvanicus, housed under long photoperiods, has shown that they prefer the odors of opposite-sex conspecifics. In this paper, we investigated the effects of short photoperiod on preferences for sex-specific odors and the production of such odors. Short-photoperiod females preferred anogenital and fecal scents of other short-photoperiod females over those of males, but did not show sexual preferences for three other scents. Short-photoperiod males did not exhibit sexual preferences for any of the odors. Furthermore, scents from short-photoperiod voles did not elicit sex-specific preferences in long-photoperiod voles, and scents from long-photoperiod voles did not elicit preferences from short-photoperiod voles. These and previous results indicate that both the odors and responses to odors change seasonally and that long-photoperiod voles respond selectively to scents from long-photoperiod voles and short-photoperiod voles respond selectively to scents from short-photoperiod voles. Taken together, these results suggest the co-evolution of seasonal changes in scents and in perceptual or other response mechanisms.