Contract grant sponsor: National Natural Science Foundation of China; Contract grant number: 30900169; Contract grant sponsor: Conservation Leadership Program (CLP); Contract grant sponsor: Fauna and Flora International (FFI); Contract grant sponsor: International Foundation for Science (IFS).The first two authors contributed equally to this work.
Sleeping Tree Selection of Cao Vit Gibbon (Nomascus nasutus) Living in Degraded Karst Forest in Bangliang, Jingxi, China
Article first published online: 5 JUL 2012
© 2012 Wiley Periodicals, Inc.
American Journal of Primatology
Volume 74, Issue 11, pages 998–1005, November 2012
How to Cite
FEI, H.-L., SCOTT, M. B., ZHANG, W., MA, C.-Y., XIANG, Z.-F. and FAN, P.-F. (2012), Sleeping Tree Selection of Cao Vit Gibbon (Nomascus nasutus) Living in Degraded Karst Forest in Bangliang, Jingxi, China. Am. J. Primatol., 74: 998–1005. doi: 10.1002/ajp.22049
- Issue published online: 26 SEP 2012
- Article first published online: 5 JUL 2012
- Manuscript Accepted: 28 MAY 2012
- Manuscript Revised: 27 MAY 2012
- Manuscript Received: 11 JAN 2012
- National Natural Science Foundation of China. Grant Number: 30900169
- Conservation Leadership Program (CLP)
- Fauna and Flora International (FFI)
- International Foundation for Science (IFS)
- Cao Vit gibbon;
- sleeping behavior;
- predation avoidance;
- range defense
We studied the sleep-related behavior of two Cao Vit gibbon (Nomascus nasutus) groups in Bangliang Nature Reserve in Jingxi County, China between January 2008 and December 2009 to test four hypotheses related to sleeping tree selection (predation avoidance, thermoregulation, food access, and range defense). Gibbons entered sleeping trees 88 ± SD 37 min before sunset before their main potential nocturnal predator become active. They usually moved rapidly and straight to sleeping trees and kept silent once settled. Over the course of the study, gibbon groups used many (87 and 57 per group) sleeping trees and reused them irregularly. They also tended to sleep in relatively tall trees without lianas, choosing small branches close to the treetop. These behaviors would make it difficult for potential terrestrial predators to detect and approach the gibbons. Therefore, these results strongly support the predation avoidance hypothesis. Gibbons tended to sleep closer to ridges than to valley bottoms and they did not sleep at lower elevations in colder months. They thus appeared not to select sleeping trees to minimize thermoregulatory stress. Gibbons very rarely slept in feeding trees, instead generally sleeping more than 100 m away from the last feeding trees of the day or the first feeding tree of the next morning. These patterns led us to reject the food access hypothesis. Lastly, we did not find evidence to support the range defense hypothesis because gibbons did not sleep in overlap areas with neighbors more often than expected based on the proportion of overlap and exclusively used areas. Am. J. Primatol. 74:998-1005, 2012. © 2012 Wiley Periodicals, Inc.