2021 Volume 37 Issue 1 Pages 5-15
Japanese macaques (Macaca fuscata) raid villages to obtain crops and other foods, such as the fruit of abandoned persimmon trees, fallen rice ears, second growth of rice, and other crop residues that are of no value to humans but can attract macaques and cause them to settle near villages. This study quantified the effects of persimmons and unplowed paddies after harvest that supply second growth of rice and herbs as food for raiding macaques. We observed the Kurodani A macaque group in Ishikawa Prefecture in the autumn of 2019. The number of persimmons decreased rapidly from the second half of October to the first half of November and decreased moderately after that. After harvesting paddies, the area of unplowed paddies decreased moderately from its peak in the first half of October. After October, the macaque group spent 30~40% of its daily activity time in villages and farmlands, forging mainly for persimmons, chestnuts, rice ears, and herbs. The group raided five or six villages until the first half of November, but after the second half of November it mainly raided two villages where most of the persimmons and unplowed paddies remained. Analysis using a generalized linear mixed model suggested that the number of persimmons and area of unplowed paddies significantly influenced raiding by the group. As countermeasures against raiding by Japanese macaque groups, we recommend removing any persimmons and plowing paddies after harvest.
