Abstract
A troop of Japanese monkeys at Takaskiyama has been artificially fed since 1953 and the population which divided into 3 and more troops grew from 250 to more than 1900 (Table 2). Artificially given food increased but, after 1975, decreased. Population parameters, especially growth rate, remaining rate to Takasakiyama, socionomic sex-ratio, adult female rate to the population size, birth rate to the adult female (natality) and primiparous age are compared with the food volume (Table 1) and with each other (Table 6). Nutrition given at the artificial feeding ground clearly influenced on the population parameters, especially on the growth rate, birth rate and primiparous age. Growth rate and socionomic sex ratio were influenced by the capture as agricultural pest, but remaining rate to Takasakiyama was not much influenced by the change of the nutrition. Changes of parameters were compared with those of the Ryozenyama population which was baited in a certain period and, then, left in the forest. The present nutrition intake by an animal at the artificial feeding ground as well as in the forest at Takasakiyama is a little more than that taken by wild animals. This study suggests that the artificial feeding should be controlled to the similar nutritional condition as that for wild animals.
