Arginine vasotocin (AVT) is a potent regulator of social behavior in many species, but little is known about its role in reptilian behavior. Preliminary studies suggest that AVT may play a role in the mating behavior of male red-sided garter snakes (RSGS). Here, we analyzed the role of seasons on the distribution of AVT in the forebrain of male RSGS. Findings from this study will point to a potential time course for AVT in cellar mechanisms responsible for reproductive behavior.