JAPANESE TOP Message from the Director Information Faculty list Research Projects Entrance Exam Visitors Publication Job Vacancy INTERNSHIP PROGRAM Links Access HANDBOOK FOR INTERNATIONAL RESEARCHERS Map of Inuyama
BONOBO Chimpanzee "Ai" Crania photos Itani Jun'ichiro archives Guidelines for Care and Use of Nonhuman Primates(pdf) Study material catalogue/database Guideline for field research of non-human primates Primate Genome DB

Primate Research Institute, Kyoto University
Inuyama, Aichi 484-8506, JAPAN
TEL. +81-568-63-0567
(Administrative Office)
FAX. +81-568-63-0085

Copyright (c)
Primate Research Institute,
Kyoto University All rights reserved.


Chen / Poster

Ecology of the black-crested gibbon (Hylobates concolor) in the Ailao Mt.Reserve, Yunnan, China

N. Chen

     National Center for Genetic Engineering and Biotechnology National Science and Technology Development Agency of Thailand A study focusing on the field ecology and behavior of wild black-crested gibbons (Hylobates concolor) was carried out in the Ailao Mt. Reserve, Yunnan Province, People's Republic of China from April 1991 to June 1993. The black-crested gibbon is a highly distinctive member of its family in that it is probably polygamous (Haimoff et al. 1987, Bleisch & Chen, 1991) while other gibbon species live in small monogamous groups (Leighton, 1987). Their habitat is unique among gibbons. The annual mean temperature is only 10.1 °C. The coldest month, December, has a mean temperature of 3.6 °C. Annual evaporation is 1383.8mm, while annual precipitation is 1530.4mm. Over the course of one year, snowfall was recorded on six days. The canopy was continuous and low with a mean height of 23.9m (n=110, s=0.6). All 2,349 trees with DBH >=10cm in three 100m x100m plots were measured and identified. DBH averaged 24.1cm (N=2,349 s = 15.7). The trees and the 89 large woody climbers in the three 1-ha plots were found to belong to 59 species of 24 families. Fagaceae (619 trees) and Theaceae (444 trees) represented the largest families. The five most abundant species accounted for 1,018 trees. No trees of the genus Ficus were found. Ripe fruits were available only from August to November, for a total of 12 weeks (N = 25 species, s=2.17).
     Behaviors were sampled with scan sampling, instantaneous recording method. The study group was composed of four individuals: one adult pair, one juvenile and one infant of unknown sex. The group was observed for 70 hours in 278 scanning recordings, resulting 946 observations. The group was estimated to be active for 8 hours 29 minutes per day. The activity time budget was: resting (39%), traveling (28%), feeding (19%), playing (8%), grooming (5%) and calling (1%). On a 30 day sampling period, the group called on 13 mornings and only the adult pair called. Calling duration averaged 13 minutes (n = 13, s=5.1). The percentages of time for the group spending on feeding deferment types of food were as follow: leaves (54%), fruits (24%), insects (14%), flower buds (6%) and unknown (2%). The group occupied a home range of 87 ha. The day range length was estimated as 1306 m. The main study group ranged on an elevation of 2,600 m above sea level, which is a record height for all gibbon species.

Bleisch, W. & Chen, N. (1991) : Ecology and behavior of wild black-crested gibbons (Hylobates concolor) in China with a reconsideration of evidence for polygyny. Primates 32(4) : 539 - 548
Haimoff, E.H; Yiang, X.J.; He, S.J. & Chen, N. (1987) : Preliminary observation of wild black-crested gibbons (Hylobates concolor) in Yunnan Province, People's Republic of China. Primates 28(3) : 319 - 355
Leighton, D.R. (1987) Gibbons: Territoriality and monogamy. In Smuts, B.B.; Cheney, D.L.; Seyfarth, R.M.; Wrangham, R.W. & Struhsaker, T.T. (Eds.), Primate Societies (pp. 135-145). Chicago and London: University of Chicago Press.