Altitudinal Ranging of Black-Crested Gibbons at Mt. Wuliang, Yunnan: Effects of Food Distribution, Temperature and Human Disturbance

We studied the altitudinal ranging of one habituated group of black-crested gibbons (Nomascus concolor) at Dazhaizi, Mt. Wuliang, Yunnan, China, between March 2005 and April 2006. The group ranged from 1,900 to 2,680 m above sea level. Food distribution was the driving force behind the altitudinal ranging patterns of the study group. They spent 83.2% of their time ranging between 2,100 and 2,400 m, where 75.8% of important food patches occurred. They avoided using the area above 2,500 m despite a lack of human disturbance there, apparently because there were few food resources. Temperature had a limited effect on seasonal altitudinal ranging but probably explained the diel altitudinal ranging of the group, which tended to use the lower zone in the cold morning and the higher zone in the warm afternoon. Grazing goats, the main disturbance, were limited to below 2,100 m, which was defined as the high-disturbance area (HDA). Gibbons spent less time in the HDA and, when ranging there, spent more time feeding and travelling and less time resting and singing. Human activities directly influenced gibbon behaviour, might cause forest degradation and create dispersal barriers between populations. Copyright (C) 2010 S. Karger AG, Basel

We are indebted to Dr. Natasha L. Wiggins, Stephen J. Simpson, Ford R. Denison, David Raubenheimer, and two anonymous reviewers for the extensive language revision, comments, and suggestions of the draft of the manuscript. We thank Si Wu, Ting Zhou, and Yan Luo for help during the period of experiments and natural data collections. This program was supported by the National Basic Research Program of China (2007CB411600), the National Natural Science Foundation of China (30670272, 30770500, 10761010), the Yunnan Natural Science Foundation (2009CD104), and the West Light Foundation of the Chinese Academy of Sciences. Support was also received from the Yunnan provincial government (20080A001) and the Chinese Academy of Sciences (0902281081) to D. W. Yu.