Distribution, abundance and habitat evaluation of Asian vultures along Kaligandaki Corridor, Nepal

Scavengers perform crucial ecological role by consuming animal carrion and thereby controlling the spread of harmful diseases. In recent decades, vulture species populations have declined across Southeast Asia due to anthropogenic disturbances such as indirect poisoning, land-use change, electrocution and shortage of carrions. This study was conducted aiming to assess the distribution, abundance, and habitat evaluation of Asian vultures in Kaligandaki Corridor, Nepal. Field observations were conducted through the birding routes, visit of nesting and roosting sites and fixed-point surveys. A questionnaire survey was also done to identify people’s perception of the status and threats on Asian vultures. In total, 99 individuals representing five vulture species were recorded in total 21 observation points along the Kaligandaki River Corridor (57 individuals in 12 different points during the summer visit and 42 individuals in nine different points during the winter visit). Remarkably only two species, White-rumped Vulture (Gyps bengalensis) and Red-headed Vulture (Sarcogyps calvus), were recorded at Khaireni Community Forest (KCF) with a total of 63 individuals (37 individuals in summer and 26 in winter). Vulture sightings and abundance were relatively higher during summer than in winter. The White-rumped Vulture was the most abundant species and Red-headed Vulture was found to be the least abundant species recorded in both seasons in the study area. Only the nest of White-rumped Vulture was observed at KCF. Simal (Bombax ceiba) was found to be the most used tree species for nesting by vultures. Vultures were found in highest densities in the forest habitat followed by agricultural land, riverbank, settlements and rocky areas. Distance to water, distance to forest and distance to agricultural land showed positive association with abundance of vulture in summer whereas distance to settlement land, distance to Vulture Safe Feeding Sites (VSFS) showed significant association to abundance of vulture species during winter. Food scarcity, habitat loss, lack of conservation awareness, use of chemicals and hunting were some of the threats for population decline of vultures in the area. For the long-term conservation of vulture species, community-based conservation programs, awareness campaigns and provision of economic incentives to local people should be conducted in all its range areas by government authority and concerned organizations.