The population dynamics of Japanese macaque troops at Hieizan was studied. Birth rates of Hieizan A and B troops were relatively higher than other wild and provisioned populations, and the infant mortality of the B troop was as low as those of provisioned troops. The B troop was provisioned by tourists and Ootsu city along the Hieizan Driveway. Artificial foods given by tourists were estimated to be more important than Ootsu city provisioning in terms of food quality and feeding time. In winter and spring, when natural foods were scarce or many tourists came to the driveway, the Hieizan B troop depended on artificial foods given by tourists. In summer and autumn, they ate crops and natural foods, such as fruit. The nutritional condition of this troop may have been improved by feeding on these artificial foods, to the same extent as systematically provisioned troops. The relatively high birth rate and low infant mortality of the troops at Hieizan resulted from non-systematic provisioning by tourists, some provisioning by Ootsu city, and dependence on crops.
This study has great importance for the management of Japanese macaques at Hieizan. It is necessary for the local government to make efforts to stop provisioning, which causes population growth and habituation, and might increase damage to crops by Japanese macaques.

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Hunting and meat-eating behavior by the genus Pan are reviewed from the perspective of the prey species. These behaviors have been reported for wild chimpanzees (Pan troglodytes) at 14 study sites, and include all three sub-species of the chimpanzee, in population from West to East Africa in environments from savanna to rain forest. The main targets of hunting and meat-eating by chimpanzees are non-human primates: of 12 study sites where prey species were identified, non-human primates other than chimpanzees were hunted or eaten by chimpanzees at 11 sites. Hunting and meat-eating by wild bonobos (Pan paniscus) have been reported at three study sites. The targets of hunting and meat-eating were restricted to small mammals such as flying squirrels or infant duikers. Interspecific relationships between the bonobos and sympatric nonhuman primates, which are the main targets of hunting and meat-eating by chimpanzees, were non-antagonistic. The common ancestor of Pan and humans may have acquired its meat-eating habit in a forested environment since gorillas and orangutans do not hunt. It seems that hunting and meat-eating played an important role in human evolution after the appearance of Homo.

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Several species of primates transfer acoustic information to members of other species as well as their own species. This paper reviews some studies of interspecific information transfer by vocalization in primates and proposes the significance of it in cognitive ethology. There are three kinds of situation that interspecific information transfer occurs: 1) polyspecific association in grouping 2) sympatric species 3) competitors and predators. Some transfer patterns are mutually beneficial while others are parasitic. Interspecific information transfer is important as a key to study primate cognition because it could represent the ability of mental attribution. In this view, some plans for studies of intention are discussed.

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