Nest site selection and threats to nesting colonies of white-rumped Vulture (Gyps bengalensis) in Himachal Pradesh

Abstract

White-rumped Vulture (Gyps bengalensis) suffered the most significant population decline among the three species of Gyps vultures impacted by the South Asia-wide diclofenac toxicity of the 1990s. Although the population lost about 99 % of its individuals, nesting populations still remain in a few pockets in India. One such population is known from the Himalayan foothills in the Kangra region, representing the northernmost nesting population of the species in India. From 2020–2024, we carried out an extensive study on the nesting ecology of the species, identifying 17 colonies with 617 active nests in 553 trees in an area of 5739 SqKm, constituting the highest nesting population reported in India. The smallest colony had ten nests, while the largest had 68. Except for a single nest on a Ficus religiosa tree, all others were on old-growth Chir Pine, Pinus roxburghii, having an average GBH of 254.8 cm (± 49.3 SD). By analyzing 18 variables, we determined vulture preferences for nest tree characteristics. Results indicate that nesting site selection primarily depends on GBH, canopy cover and nearest nest distance. About 80 % of nests were found between 600 and 800 m elevation. The primary threats include forest fire, resin tapping, and tree felling. We recommend protecting larger-sized old-growth forests through awareness campaigns with forest managers and local communities to safeguard the nest sites of the critically endangered bird.