The Influence of Tree Characteristics on White‐Backed Vulture ( <i>Gyps africanus</i> ) Nest‐Site Selection in Manyeleti and Kempiana Nature Reserves, South Africa

Abstract

An understanding of nesting tree characteristics is essential for the conservation of Critically Endangered White-backed Vultures (<i>Gyps africanus</i>). To assess the influence of tree characteristics and tree health on White-backed Vulture nest-site selection, we measured a total of 205 trees (including vulture nest trees and randomly chosen trees) in Manyeleti and Kempiana Nature Reserves, South Africa. For each tree, we recorded trunk circumference at 1.3 m (CBH1) and 0.3 m (CBH2) above ground level, canopy width at its widest point, and total height. Tree health was evaluated based on trunk damage, including fire scars, insect infestation, fungal presence, and elephant debarking. <i>Diospyros mespiliformis</i> was the most frequently selected tree species (10.2% active nests). Most trees (74.2%) were healthy, 18.1% were unhealthy, and 7.8% were very unhealthy, primarily due to debarking by African savanna elephants (<i>Loxodonta africana</i>). There was no significant relationship between tree health status and vulture nest presence. Vultures prioritized tree size over tree health. Logistic regression identified trunk circumference as a key predictor (<i>p</i> = 0.030, <i>z</i> value = 2.175), with larger trees associated with increased odds of nesting (coefficient: 0.587 ± 0.270), likely due to better support for the nests and higher elevation. However, insects and fungi reduced tree survival, and this was worsened by elephant damage. Conservation practitioners should focus on protecting <i>Diospyros mespiliformis</i> by managing elephant densities and controlling burns to mitigate vulture nesting tree damage and habitat stress.