Status and distribution of hoolock gibbon in the newly established Indawgyi Biosphere Reserve: Implication for protected area management

Protected areas are an important tool for conserving biodiversity, if they are managed appropriately. The effectiveness of protected area management can be evaluated by understanding the conservation status of indicator species. Here, we investigate the Vulnerable eastern hoolock gibbon Hoolock leuconedys in forest blocks in Indawgyi Biosphere Reserve, Myanmar. We assess the species’ status, the influence of human disturbance and topographic factors and evaluate the reserves management. Surveys of gibbons were undertaken between October 2018 and May 2019 using an auditory sampling technique at 59 sites, covering 95 km2 . We applied Distance Sampling techniques to estimate the number and density of gibbon groups and investigate if gibbon density were influenced by landscape and human activities. We estimated average gibbon density to be 0.71 groups per km2 . Our results suggests that Indawgyi Biosphere Reserve holds a generally low density of eastern hoolock gibbon in Myanmar, compared to other similar sites in the region. Gibbon density was influence negatively by slope and elevation and positively by distance from villages. The current management interventions in Indawgyi Biosphere Reserve are not sufficient to conserve gibbons and reducing human disturbance is a conservation priority. We make management recommendations to improve protection of the gibbons, as well as other wildlife species.