Abstract
A field survey was conducted in 2010 from March to May in the reserve forests of Sadiya sub-division, in the Tinsukia District of Assam, India, to investigate the status of the Hoolock Gibbon. The data were collected using modified line-transect and call-count methods. We recorded 10 groups of gibbons in three reserve forests, through direct sighting. Of the 33 individuals recorded through direct sighting 63.6% were adults, 21.2% juveniles and 15.2% infants. The average group size of the sighted groups was 3.3 individuals, with an adult sex ratio of 1:1.1. We also recorded 10 groups of Rhesus Macaques in the area. Anthropogenic pressures included encroachment, felling of trees and inadequate infrastructure, and these were the major threats for Hoolock Gibbon and other wildlife in the region. Notably, the gibbons of Sadiya have been identified as the Eastern Hoolock Gibbon Hoolock leuconedys and this is the first report of the species from Assam.
Highlights
Assam, one of the seven states in northeastern India, supports a rich biodiversity, with primates forming an important component
We report the anthropogenic pressures on the species and its habitats, so that effective conservation measures can be developed for Eastern Hoolock Gibbon in the study area in future
Based on our observation we have identified the following threats: Status of the forest: It is evident that Eastern
Summary
One of the seven states in northeastern India, supports a rich biodiversity, with primates forming an important component. The Western Hoolock Gibbon is so far the sole ape recorded from Assam. Several studies have already been carried out on the status and distribution of Hoolock Gibbon in Assam (Mohnot 1995– 2001; Das et al 2005; Chetry et al 2007; Choudhury 2006, 2009; Kakati et al 2009). Sadiya is a subdivision of Tinsukia District of Assam and it is the extreme eastern boundary of the state. There are six reserve forests in the subdivision of Sadiya range of Doomdooma Forest Division of eastern Assam circle. Studies were carried out from time to time to understand the primate diversity of the state, including Sadiya. The Indo-US Primate project first did an extensive primate survey in Sadiya
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
