Daily Activity Budget And Social Structure Of Rhinopithecus Roxellana In Qinling Mountains

This study was conducted on a Qinling golden snub-nosed monkey (Rhinopithecus roxellana) troop ranged in the West Ridge of Yuhuangmiao Village (named WRT), Zhouzhi National Nature Reserve, Shaanxi Province of China from February 2004 to August 2005. The WRT lived in deciduous broadleaf forests and mixed coniferous broadleaf forests, from 1400m to 2400m above the sea level. One part of this troop was provisioned whereas the other part not. The sex-age category was classed according to the individual identification. The social structure and time budget of the WRT was carried out in this study. The related behavioral data were collected by ad lib sampling, scan sampling, focal animal sampling, instantaneous sampling and all occurrence recording according to the different research purpose on study subject. The result in this study showed that: Two types of its basic social organization, One-male unit (OMU) and All-male unit (AMU), formed the Troop. The whole troop consisted of 12 OMUs and 2 AMUs, which is about 150 individuals at total and the rate of different sex-age class was adult males: adult females (3.58:1) (0-8:1) and adult females : infants (2.25:1) respectively.The mean individual numbers within the OMU was 11 (range: 4-28). The composition of OMU was relatively stable although it varied from seasons and years. The variation of OMUs' composition came from infant birth, infant mortality, individual migration, unit dismissing and unit buildup. The subjects involved in migration include juveniles males, sub-adult females and adult females. Such variation on OMUs' makeup influence the composition of troop. Male replacement and inter-unit juvenile female migration might serve as mechanism of inbreeding avoidance to some extent.AMUs moved around the edge of the WRT and their members often attempted to approach females within OMUs whereas the resident male of OMU kept AMU's males from their females. The diurnal activity budgets in the WRT was: monkeys moved a short distance after waking up and foraging in the morning; they rest for 2 hours after noon then forage again, and stop moving until evening, finally they chose a place for sleeping. The subjects spent the majority of their time feeding and resting, (34.64±1.70%) and (26.83±1.69%) of all activities respectively. The other activities were grooming (11.58±0.96%) , locomotion (18.93±1.08%) and other behaviors (8.02±0.82%). Time, season and age-sex class were observed to influence the activity budgets of the subjects. Feeding activity of the study group showed two peaks, one in the early morning (8:00-10:00), and another in the afternoon (16:00-18:00). A resting peak was observed around noon (12:00-14:00). The behavior category varied significantly among sex-aged classes in different seasons. The adaptation on the local habitat and climate in Qinling Mountains was considered as one of thoese reasons on such behavioral change in this monkey troop.