A survey was carried out on the overall langur population size in Bapen Reserve. Data showed that local extinction has been occurring for a long time, due to habitat destruction and hunting. However, a drastic population decline has taken place over the past ten years. Most langurs were found in a hill-group in which the Reserve staff members often patrol. This hill-group was defined as the main langur population pool of the Reserve. Further detailed sampling in this area showed a much higher population density compared to other hill-groups. Langurs preferred large areas of continuous habitat. A similar survey was carried out in Longgang Reserve, Ningming County, which indicated a high population density in the central area of that reserve where the habitat has been much less disturbed by humans. In the main population pool, data were collected on climate, distribution of vegetation patches, plant species richness, phenology of food plant species, feeding ecology, range use and group dynamics. Habitat quality was classified according to the extent of human disturbance. Results showed that a large amount of mature leaves was available year round. Young leaves maintained a low level of availability, but disappeared almost completely in the winter of 1997. Rainfall was seasonal and was linked to the production of fruits and young leaves. Vegetation was mainly distributed on the lowest 40% of the hills. Behavioural data showed that the activity of white-headed langurs was restricted on the hills by the distribution of vegetation. Langurs fed mostly on rare plant species. These were more likely to occur in higher quality habitat, for which different langur groups competed. As a consequence, only the langur groups living in 50% of the higher quality habitat area produced offspring. Langurs fed intensively on young leaves. Compared to other colobine species, white-headed langurs were extremely folivorous. This seemed to be related to their smaller area of range use.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:653875 |
| Date | January 2000 |
| Creators | Li, Zhaoyuan |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/11050 |
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