There were ¸6 troops of macaques in Jentse, the largest of which contained
31 individuals (Su, 1993). From October 1991 through June 1992
(excluding January), we visited the study site twice per month and stayed
3–4 days each time to conduct fieldwork on the macaques. In January 1992,
we visited the site only once, but stayed for 6 days. To assess whether more
intensive observation would affect the results in terms of macaque dietary
composition, we also stayed at the study site for longer spans and conducted
fieldwork intensively between July and September 1992. The total number
of working days during these months is 44. The total time spent in the field
during the course of the study is 1,286 hours. Each month we routinely surveyed
the same sections of paved road and trails (survey routes) to look for
macaques and to collect their feces (Fig. 1). Once the macaques were spotted,
we followed them to record their behavior until they were out of view.