A Comparison of the Fecal Compositions of Sympatric Populations of Sika Deer and Japanese Serows on Mt. Sanrei in Shikoku, Southwestern Japan

Abstract

Two ruminants, sika deer (Cervus nippon) and Japanese serows (Capricornis crispus), inhabit the Japanese archipelago. The range of sika deer includes nearly the entire archipelago from Hokkaido to Kyushu, including habitats from the coastal zone to the montane zone. In contrast, the distribution and the habitat of Japanese serows are limited: they inhabit deciduous broad-leaved forests from Honshu to Kyushu (Ohdachi et al. 2009). These two ruminants occur in sympatry in some localities. Information on such cases would help to document how two animal species within the same guild can share a common food supply. However, only one study at Mt. Yatsugatake, central Japan, has compared the diets of sika deer and serows (Kobayashi and Takatsuki 2012). Their study demonstrated that sika deer subsisted on dwarf bamboo, whereas serows mainly fed on forbs and browses (Kobayashi and Takatsuki 2012). The diet compositions of the two species were more similar in winter, likely because food was limited and both ungulates were forced to feed on similar food plants (Kobayashi and Takatsuki 2012). Although it is known that there are many more sympatric populations of these two ruminants, no other studies have been done. Further, quantitative food analyses of Japanese serows are limited, and no study has been done for southern serow populations. The present study, therefore, compares the diets of sympatric populations of these two ruminant species in the eastern part of Shikoku, an island in western Japan, representing