Latrine ecology of a solitary ungulate, the Japanese serow: female–male communication site rather than territorial marking?

Abstract The functions of latrines have been well studied in gregarious or pair-living territorial ungulates, however, there are no field-based studies on latrine behaviour of solitary ungulates with monogamous pair territories. We investigated latrine behaviour of the Japanese serow ( Capricornis crispus ), a solitary and monogamous species. The spatial patterns of latrines did not coincide with the serows’ home range boundaries, and individuals of the same sex did not defecate at the same latrine (i.e., there was no countermarking), which suggests that latrines may not function as territorial marking. During the late-mating season, when males and females tend to live separately, the number of latrine visits by females increased and the probability of defecating was significantly higher, suggesting that females are the signallers, informing their oestrus status to males. Moreover, males also frequently visited the latrines, and latrine sniffing and overmarking were observed only during the late-mating season, suggesting that males may receive information about oestrus from the females’ faeces. Obtaining information on female oestrus directly is difficult for solitary species in which sexes live separately. Although future studies would be required to confirm this hypothesis, our study suggests that latrines may have evolved as female-to-male communication sites in the Japanese serow.