Case Study of a One-Sided Attack by Multiple Troop Members on a Nontroop Adolescent Male and the Death of Japanese Macaques (Macaca fuscata)

摘要

members of the troop. The victim was identified as PI, and was estimated to be seven + one year old. The aggressive interaction wasrecorded by video camera until the end. Although at least 16 troop members approached PI more than once, only three males (oneadult, two adolescents) of A troop attacked him. PI kept crouching throughout the attack, then escaped to the shore and dived intothe sea. The interaction continued for more than one hour. P1 was found dead a few hours after the end of interaction. The damagecaused by the assailants was not the direct cause of PI's death; it was due to hypothermia caused by drifting in the sea. PI's lifehistory was reconstructed from past records. PI was a normal adolescent male who migrated from an all-male group around B1troop and started ranging around A troop. The aggressive interaction is believed to be a typical example of conflict between troopmales and a nontroop male. The interaction period was very long compared with previous reports on such conflicts among Japanesemacaques. PI kept crouching in open areas, exposing himself as a potential competitor for the resources of the troop, and did notshow any submissive or reconciliatory behavior toward the troop males. This may be why the troop males did not stop the attack.Aggr. Behay. 35:334-341, 2009