Population dynamics of japanese macaques at ryozenyama: III. Female desertion of the troop

From these facts it is clear that the basic organization of the troop of Japanese macaques is the kin-group and the animals are bound by the head of the Kin-group or elder mothers but that intra-kinship social bonds as well as inter-kinhip bonds gradually weaken in old females.

Abstract

Troop desertions by females which were observed in Japanese macaque troops at Ryozenyama between 1969 and 1978 are described and the factors which drive females out from the troop are discussed with reference to the troop desertion by males and to the social structure of Japanese macaques. There were 14 cases and altogether 22 female deserters of 5 or more years old; ratio(%) of frequency of the female desertion to the total number of females was 9.48 a year. Female deserters of less than 10 years old had no mother in the troop and belonged to rather isolated kin-groups on the periphery of the troop prior to desertion except for those who deserted it with their mothers. Old deserters were not always very peripheral ones and some of them cut kinship bonds when doing so. Many female deserters were found in or near the moving range of the original troop and some came back to it. They were easily accepted without antagonism and they were expected to retain the potential membership of their natal troop. From these facts it is clear that the basic organization of the troop of Japanese macaques is the kin-group and the animals are bound by the head of the kin-group or elder mothers but that intra-kinship social bonds as well as inter-kinship bonds gradually weaken in old females.