Altitude Preference of Trachypithecus melamera in Longlingxiaoheishan Nature Reserve

In order to understand the behavioral response of Trachypithecus melamera to human activities and seasonal variation of food rescources, we followed and collected data on positions of a group of 20 Burmachinese Gray Langurs (T. melamera) every 30 mins using a GPS receiver, on diet using instantaneous and scan sampling at 10-min intervals, and on their behavioral responses to human activities in Longlingxiaoheishan Provincial Nature Reserve from August 2019 to July 2020. The Langurs' home range was stratified into six gradients of elevation from 1700 to 2300 m every 100 m interval. Then we evaluated the effect of diet and human activities on altitude preference of T. melamera during study period, and in wet and dry season, respectively. The results indicated that there are significant differences in altitude utilization yearly, and both in wet and dry seasons. The pattern of annual altitude utilization was unimodal with the highest frequency of elevation utilization belt of 1800–1899 m. The langurs mainly used the altitude belt of 1800–1899 m and 1900–1999 m in wet season(55.8%), and 1800–1899 m and 2000–2099 m in dry season (52.0%). Human activities occurred at all elevations, with the highest frequency at 2100–2199 m and the highest intensity at 1900–2099 m. The annual altitude use of T. melamera was not affected by the number of disturburce events and number of human beings. The altitude preference of T. melamera were influenced by the proportion of time spent on leaves throughout the year, also related to the proportion of time spent on buds/young leaves in wet season, and that of flowers and fruits in dry season. Therefore, the altitude preference of T. melamera is mainly related to the spatial and temporal distribution of food resources. Moreover, the langurs were nervous when facing with human beings, and avoided the changed habitat. Our results suggested that strengthening the management of long-term human disturbance activities, limiting the expansion of disturbance areas, will useful to promote the conservation of the species and biodiversity in the region.