Bioacoustics of Macaca tonkeana

Movements, Home range and Social organization. Tonkean Macaques live in multimale-multifemale groups. Mean group size is 24 individuals (range 6-35), with an adult male to adult female sex ratio of 1:0-6-1-3. Subgrouping has been observed. Females form linear dominance hierarchies, but they show relaxed relationships characterized by low levels of intense aggression, bidirectionality when agonistic behavior occurs (either female in a dyad may initiate the interaction), frequent post-conflict affiliative contacts, and an overall high degree of social tolerance (e.g. feeding together). Adult males also show social tolerance as exemplified by low levels of agonistic behavior and frequent grooming interactions. Adult males (typically the highest ranked) emit a birdlike vocalization called a “loud call.” These calls appear to function primarily to influence intragroup cohesion, i.e. to communicate information with regard to location and movement within the social group. Home range size is 45-143 ha, and the ranges of neighboring groups often overlap. Tonkean Macaques are flexible in response to habitat alteration by intensively using particular areas within their home range where known resources are present and predictably available (e.g. A. pinnata palms). Individuals also increase their home range size under such conditions. Mean daily movement is 1175 m. Densities of Tonkean Macaques are 20-67 ind/km? across their distribution.