Mother-infant Relationships, Male Care And Infant Development Of Wild Sichuan Snub-nosed Monkeys (Rhinopithecus Roxellana) In Qinling Mountains

From March 2003 to May 2005, we conducted the study on the mother-infant relationships, male care and infant development (during their second years) of wild Sichuan snub-nosed monkeys (Rhinopithecus roxellana) at the Zhouzhi National Nature Reserve of the Qinling Mountains. Focal animal sampling, instantaneous sampling and all-occurrence recording method were applied in our study.The results showed that unit changing, unit composition, maternal parity and some environmental variables, such as climate, can influence the mother-infant relationships of Sichuan snub-nosed monkeys.From birth to eight months old, there was a significant negative correlation between the age of infants and the percentage of time mother-infant dyads spent in contact. But from nine months to eleven months, the amount of time spent in contact between mothers and infants increased.The furthest distance between mothers and infants increased with infant age. In the first month, the distances never exceed 1m. In the second month, the distance increased to 5m. From the third month afterwards, the distance increased quickly, and the range stabilized between 20 to 30m.Unit changing might cause increasing amount of time on mother-infant contact. Unit size and organization also have effects on the relationships between mothers and infants. If there were enough peers in unit, infants would spend less time with their mother, vice versa.Male care took place most in winter. Infants who were seven to nine months old received more care from males. This result may be caused by the special weaningperiod these infants suffering.On average, infants achieved total locomotor independence when they were sixteen months old, and they won't suck any more when they were nineteen months old. But there existed significant individual difference.Except their mothers, infants preferred to interact with peers and sub-adult females.In different season, infants spent different amount of time in playing, resting and feeding. Infants' playing behavior was. quite common in spring and fall. In winter, the most time of infants were occupied by resting and feeding.