ECOLOGICAL NICHE MODELLING OF HIMALAYAN LANGUR (Semnopithecus entellus) IN SOUTHERN FLANK OF THE HIMALAYA

The species and subspecies status of various populations of the Himalayan langur (Semnopithecus entellus) have been disputed in many literatures. Before delineating the taxonomic boundaries, it is important to identify the potential distribution areas of extant populations of the species. Ecological niche modeling (ENM) can be coupled with the systematic survey of species presence to identify the species’ potential distribution range. Therefore, we did extensive survey and population census of the Himalayan langur across three major river basins (Koshi, Gandaki and Karnali) of Nepal and analyzed the population patterns. In addition, we also modelled the ecological niche of the species by using maximum entropy (MaxEnt) algorithm. We counted a total of 559 individuals from 33 troops that accounted the average troop size of 16.94 (±8.39) individuals. Within Nepal territory, the highest population of langurs was observed from the Gandaki River basin followed by the Karnali River basin. We revealed that Himalayan langurs have a wide range of altitudinal (49 m - 4190 m above sea level) distributions from Bhutan to Kashmir across southern flank of the Himalaya. We warrant for the detail distribution assessment and taxonomic analysis of Himalayan langurs using ecological, morphological and genetic variables.

Metacommunication in social play: the meaning of aggression-like elements is modified by play face in Hanuman langurs (Semnopithecus entellus)

The metacommunication hypothesis asserts that some elements of play behaviour are associated with play elements borrowed from aggression and interpret these aggression-like elements as playful. Using data from free living Hanuman langurs (Semnopithecus entellus), we tested three predictions that follow from the metacommunication hypothesis: (i) aggression-like elements (ALEs) abbreviate play bouts; (ii) candidate signal elements are sequentially associated with ALEs; (iii) associations of candidate signal elements with ALEs prolong play bouts. Play face and five other candidate signal elements were evaluated in relation to nine ALEs. We confirmed all three predictions for play face, albeit only if the play face and/or the ALEs occurred at the start of the play bout. The other candidate elements were not associated with ALEs. We conclude that play face fulfils the metacommunicatory function in Hanuman langur play bouts, while other play specific elements may serve other signal or non-signal functions.

Social interactions of Hanuman langur (Semnopithecus entellus) at Keshabpur and Manirampur of Jessore district of Bangladesh

Social interactions of Hanuman langurs (Semnopithecus entellus) were studied from August, 2013 to July, 2014 at Keshabpur and Manirampur Upazila, Jessore, Bangladesh. The study was mainly based on direct field observations from dawn to dusk and data was collected through focal animal sampling in 10- minutes duration. During the study period seven groups of Hanuman langurs were found in urban and rural habitats. Eight behavioral activities like resting, feeding, grooming, moving, parental care, playing, submission and aggression were recorded. They interacted with each other through grooming, parental care, playing, submission and aggression. Social interactions varied in urban and rural habitats. Aggression was mostly observed in rural habitat and generally showed by the males. Adults were engaged in playing to encourage infants, juveniles and sub-adults. Significant seasonal variation of grooming was observed between age classes. Females were engaged more in grooming and parental care than males. Allomothering was also observed within a group. More submission was received by dominant males within a group. Langurs of focal groups spent 41.04% of their total activity budget in resting which was the highest activity followed by 33.75% in feeding, 11.73% in grooming, 4.87% in moving and 8.61% time for other activities.Bangladesh J. Zool. 42(2): 217-225, 2014