Reproduction Behaviour And Diet Of Black-and-white Snub-nosed Monkey {Rhinopithecus Bieti) At Mt. Lasha, Yunnan

Copulation patterns are important to understanding male mating strategies and stabilization strategies of social organizations in primates. However, information on copulation patterns of Asian primates is relatively rare. This study was undertaken to collect data on mating behavior and birth seasonality of Black-and-white Snub-nosed monkeys(Rhinopithecus bieti) using all occurrence sampling and Focal animal-scan sampling methods at Mt. Lasha, between January and December,2011. Our study focused on observing mating frequency and birth rates. Snub-nosed monkeys mate year round, with two observable peaks:one reproductive peak during the mating season, roughly from August to October, and a second non-breeding peak during the birth season. It is unclear what biological significance this non-reproductive mating peak has. During our observation, we noted a lower ratio of mount to ejaculation and rare ejaculatory copulations, which indicated that every mating would not result in ejaculation. This study corroborates the previous view that the Rhinopithecus bieti’s copulatory pattern is likely multiple-mount ejaculation (MME) or at the upper part of mating continuum of single-mount ejaculation (SME) toward MME. More ejaculatory copulations initiated by males than females indicate that MME is not only a mating strategy of males, but that males can influence the position of their copulato ry pattern on the continuum between SME and MME. The mating frequencies significantly correlated with the birth rates with a delay of6to7months. Monkeys gave birth within a strict seasonality with a birth peak of March, which confirms the previous view. Infants were born with a certain degree of synchronization, but different populations displayed different modes of synchronizations.Data on relationship between infants and adult female, adult male and juvenile, and on infant developmental behavior of R. bieti were collected by focal animal-scan sampling method at Mt. Lasha from February2010to January2011. The infant body color changed from February2010to January2011.Their color of back, head hair, the lateral of foreleg, body side and tail from white changed to white-gray and black-grey. The same behaviour of R. bieti at Mt. Lasha was later then the captive group. It was maybe that environment condition of captive monkey was better then the wild group.From birth to eight weeks old, the infant began feeding other food except the milk of mother, after eleven weeks the infant began to play with other member of the monkey group, and after twenty weeks the infant can moved with the mongkey group without monther carry. Up to the age of one years of the infant occurrence of nipple contact decreased. Yearly percent time of infant care (PIC) by adult female is82.5±5.2(51.5±18.3BC,19.5±9.1IP and11.5±6.5G). Yearly PIC by juvenile is12.6±3.4(3.1±4.5BC,6.8±3.3IP and2.7±2.3G). Yearly PIC by adult male is4.8±4.5(0, BC,3.1±3.0IP and1.7±1.5G). The adult male total PIC and the adult female total PIC was negative correlation. Juvenile-care of the infant can not only reduced the female pressure, immaturity female but also can learned how to became a mother from this process.The PIC of adult male care of R. bieti at Mt.Lasha was4.8%and this was belong to none intense male care.This may be due to at Mt.Lasha the monkeys’ energetic stress was lower then Xiaochangdu group.The study group of R. bieti ate39species from18families at Mt.Lsha from September2010to September2011. These food species include two species of the lichen,37kinds of seed plants. The annual diet consisted of70.5%lichens,8.6%buds,8.3%leaves,0.9%flowers,10.3%fruit,0.6%bamboo shoots,0.1%insects. Lichens also was the primary foods of R. bieti at Mt. Lasha. The Lasha subpopulation were aptto seclect for buds and flowers of broad leaf trees except lichens in spring; for bamboo shoots at the end of spring and at the summer; for fruits in autumn and for almost lichens in winter. Most of monkeys foraging behavior was nip.Different individual use different foraging behavior and this maybe depend on different physical constitution.