Demographic Profile and Population Status of Endangered Western Hoolock gibbon in Yangoupokpi Lokchao Wildlife Sanctuary of Manipur, India
DOI:
https://doi.org/10.55863/ijees.2026.1029Keywords:
Indo-Burma, Kwatha village, Home range, Group composition, Habitat loss, ConservationAbstract
The western hoolock gibbon (Hoolock hoolock), the only ape of India, is listed as Endangered and faces severe threats from habitat loss, fragmentation, and anthropogenic disturbances within its home ranges. Therefore, there is an urgent need for conservation measures for the ape, although baseline data on population status remain limited in many protected areas of Northeast India. This study revealed the population status, group composition, and encounter rate of western hoolock gibbons in the Yangoupokpi Lokchao Wildlife Sanctuary of Manipur, India, which is considered part of their natural range. A total of 43.18 km of survey walks covering 13.77 km² were conducted during November 2022 and March 2023. Six isolated gibbon groups comprising 18 individuals were recorded. The observed population consisted of six adult males, six adult females, two sub-adult males, one sub-adult female, one juvenile female, and two infants. Group size ranged from 2 to 4 individuals, with a mean of 3.0 ± 0.89 individuals per group. The group density and population density were estimated at 0.43 groups km⁻² and 1.30 individuals km⁻², respectively. The presence of sub-adults, juveniles, and infants revealed a viable breeding population within the sanctuary. These findings provided a systematic census-based population assessment of western hoolock gibbons in the Yangoupokpi Lokchao Wildlife Sanctuary of Manipur, India.
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