Behavioral Characteristics of Solitary Japanese Macaques (Macaca fuscata) in Residential Area

Distribution of Japanese macaques (Macaca fuscata) has expanded nationwide and invasion of solitary animals into residential areas has become problematic for residents and local government. We collected cases on the invasion of solitary animals into residential areas and compared sexual difference of behavior. We assembled the information (observed behavior, sex of animal, home range size, invasion month, and invasion period). During the study period (1994-2016), we collected 18 cases (28 animals), among which 12 animals were females. Both male- and female- solitary animals performed 1) crop feeding, 2) invasion to houses, 3) injury to human, and 4) attack to other animal, while only females performed 5) affinity behavior to other species, 6) sexual behavior with other species and 7) object stealing were performed only by females, and only males performed 8) damage to property. The solitary male appeared mainly in winter and spring but appearance of solitary females had no seasonality. Home range sizes of solitary females were smaller than solitary males. There were sex difference also in the unique behavior observed in solitary animals. A likely reason of the invasion of the solitary female is disturbances of the troop structure due to previous measures taken against monkey crop damage, such as capture and guard fence-setting. Our study not only adds useful information for pure science of the solitary animals, but also is useful for solving future problems of solitary animals invasion into other residential areas.