No abstract

No abstract

This paper focuses on biological relationships between mammalian species richness and the community structure of dung beetles in cool-temperate forests in the northernmost part of mainland Japan. The composition of beetle assemblages was evaluated at 3 sites in undisturbed beech forests with different mammalian fauna. In spring and summer 2009, beetles were collected at each site using pitfall traps baited with feces from Japanese macaques, Macaca fuscata Blyth (Primates: Cercopithecidae); Asiatic black bears, Ursus thibetanus Cuvier (Carnivora: Ursidae); Japanese serows, Capricornis crispus Temminck (Artiodactyla: Bovidae); and cattle. In the present study, 1,862 dung beetles representing 14 species were collected, and most dung beetles possessed the ecological characteristic of selecting specific mammalian feces. The present findings indicated that although species diversity in dung beetle assemblages was not necessarily positively correlated with mammalian species richness in cool-temperate forests, the absence of the macaque population directly resulted in the marked reduction of the beetle abundance, with the loss of the most frequent species, Aphodius eccoptus Bates (Coleoptera: Scarabaeidae) during spring.

One of the rare documented cases of an antagonistic primate-plant interaction is selective foraging by Japanese macaques (Macaca fuscata) on the bark or buds of Japanese mulberry trees (Morus bombycis) in cool-temperate forests. We examined how this selective foraging behavior influences the growth and development of mulberry trees in a large geographic space with different environmental conditions by selecting study areas in northern Japan. We found that the foraging caused potentially fatal damage to 5%-10% of the mulberry trees and led to dwarfing of the tree morphology. However, the stem density of the monitored mulberry trees was the highest in the area with a long history of occupancy by macaque groups; moreover, the foraging commonly resulted in compensatory plant growth by increasing shoot number. These findings indicate that the macaquemulberry relationship is not always antagonistic. Sufficient snow cover could be a key environmental factor to establish this non-antagonistic interaction by suppressing the negative influence of macaques as a destructive herbivore and improving their positive influence as a skilful gardener. Finally, we performed decision tree modeling based on the J48 algorithm to investigate geographic variation in mulberry abundance and morphology in response to the distribution of macaques. We developed an explicit tree model with reasonable predictive performance that not only enables a better understanding of primate-plant interactions but also provides information regarding the time of occupancy by Japanese macaques in a given area Int J Primatol (2010) 31:904-919 based on the abundance and morphology of mulberry trees. This result indicated that the observation of preferred tree species could be an indirect measure that reliably indexes macaque habitat use.