Present distribution, population status, and conservation of Western Hoolock Gibbons Hoolock hoolock (Primates: Hylobatidae) in Namdapha National Park, India

Survey and Census of Hoolock Gibbon (Hoolock hoolock) in the Inner-Line Reserve Forest and the Adjoining Areas of Cachar District, Assam, India

“…The present findings, i.e. a mean group size of 3.6 individuals for 9 groups, is closely comparable to other studies conducted in different parts of the H. hoolock distribution range, as reported in Kumar et al [2009], i.e. 3.2 individuals for 24 groups and 3.4 for 7 groups [Tilson, 1979], 3.1 for 8 groups and 3.0 for 14 groups [Choudhury, 1990[Choudhury, , 1991 in Assam, 3-3.2 for 6-10 groups [Mukherjee, 1982], 2.1 for 34 groups [Gupta, 1994] in Tripura, 3.0 individuals for 42 groups [Alfred and Sati, 1990] in Meghalaya, 3.5 for 6 groups [Gittins and Tilson, 1984], 2.3 for 5 groups and 2.9 for 15 groups [Ahsan, 1984[Ahsan, , 1994, and 2.9 for 13 groups [Feeroz and Islam, 1992] in Bangladesh ( table 2 ).…”

“…In the near future, there is a high probability of extinction for several fragmented populations [Molur et al, 2005;Kumar et al, 2009]. In the present study, fragmentation of habitat appears to have had no immediate impact on group size; however, its effect in the long term should be the subject of further study.…”

“…Following Kumar et al [2009], the line transects were laid in a stratified random design to cover all selected areas in the forest. Two observers walked slowly, covering a distance of between 10 and 15 km/day between 06.00 and 16.30 h or until sunset (2 days a week, total 1,296 contact hours; range 8-10 h, mean 9 h/day; 864 h/man/year for 1.5 years).…”

Distribution of Western Hoolock Gibbons and Nutritional Status of Food Plants in Cachar District of Assam, India: Reaching Out to Local Communities for Conservation

“…Mean group size of Western hoolock gibbons in Cachar district has been found to be smaller when compared with average mean group size from the entire state of Assam which is 3.2 (Das et al, 2009). Similar to the present study, Kumar et al (2009) reported a mean group size of 2.5 individuals for 20 groups from Arunachal Pradesh. A considerably small mean group size of 2.1 for 34 groups in Tripura was also reported (Gupta, 1994).…”

“…It is very important to understand the fundamental link between this species and its habitat for formulation of effective conservation plans (Das et al, 2005, Ray et al, 2015. The habitat of Western hoolock gibbons in Cachar district includes forest patches inside tea estates, village woodlots near forest fringes and small tree cladded areas which are in contrast to the reported habitats of Western hoolock gibbons in other parts of India that are tropical and subtropical evergreen, tropical wet evergreen, tropical semi-evergreen, tropical moist deciduous, and sub-tropical hill forests (Kumar et al, 2009). The forests of Cachar district have historically been ill-utilized and misappropriated especially during the British colonial rule and hardly any management strategy was adopted by the Indian government since then in order to maintain these forests as functional ecosystems.…”