Population genetics of the bearded vulture.

Abstract

The bearded vulture (Gypaetus barbatus) is a large, long-lived bird which inhabits high-altitude mountains across Africa, Europe and Asia. Low breeding rates and heightened persecution over the last two centuries have left many populations severely diminished or extinct. The species is globally at risk and is thus listed as ‘Near Threatened’ by the International Union for Conservation of Nature (IUCN). This global conservation status may under-represent the threats faced by local populations. The southern African population, which is the most geographically isolated, is estimated at 100 breeding pairs, and is classified regionally as Critically Endangered. This thesis aims to describe the genetic status of G. barbatus populations using a panel of 14 microsatellite loci. In the first chapter, the phylogeographic structure and genetic connectivity among G. barbatus populations across Africa and Europe will be assessed. In particular, this chapter focusses on determining if the geographically isolated southern Africa population is genetically unique. In the second chapter, the genetic diversity of the southern African G. barbatus population is compared to that of the Cape Vulture (Gyps coprotheres), Hooded Vulture (Necrosyrtes monachus) and the African White-backed Vulture (Gyps africanus). These vulture species are ecologically similar and also occur in southern Africa. In the third data chapter, the genetic data is combined with ecological and behavioural data to determine the southern African population’s future in a population viability analysis. My results show that the presence of spatial genetic differentiation and the low level of gene flow into the southern African population supports the management of this population as a separate entity. The genetic assessment of the global and southern African G. barbatus populations is useful in revising and updating the current conservation management for this species. Although the southern African population harbours more homozygosity in comparison to two other vulture species occurring in southern Africa and beyond, these bearded vultures had comparatively high allelic richness. The expected high inbreeding found in the southern African G. barbatus population highlights the need for conservation programmes to effectively manage and maintain the extant genetic diversity. Recommendations reported in this thesis will contribute significantly towards conservation efforts to ensure the sustainability of this emblematic species.