Ranging pattern and population composition of Rhinopithecus bieti at Xiaochangdu, Tibet: Implications for conservation

We studied the ranging pattern of the wild black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Xiaochangdu, Tibet from June 2003 to March 2005. Using the map grid cell method, the group home range were 16.75 km(2) in summer, 10.50 km(2) in winter, and 21.25 km(2) total over two years. The daily travel length (DTL) averaged 765 m with a range of 350-3500 m. The results showed that DTL in winter was significantly shorter than those of in summer and spring. Temperature, rainfall, food availability, and human disturbance correlated positively with DTL. According to the maximum observed group size and estimated total home range, population density and biomass of R. bieti were 9.1 individuals/km(2) and 88.6 kg/km(2), respectively. The temporal and spatial variations of food resources and patterns of human disturbance largely determine the ranging behavior of R. bieti at Xiaochangdu.