A recent paper published in Ibis (link) providesnew data on the genetic variation within, evolutionary placement of, and connectivity among sub-Saharan African populations of the bearded vulture.
African bearded vulture populations are in decline or presumed to be declining. In South Africa, where the species is well studied, there has been a 50% decline over the last few decades, with a significant range contraction – it numbers only 109 pairs currently. The species has disappeared or is the verge of extinction throughout Eastern Africa (Kenya, Tanzania and Uganda, 10 pairs), and the Ethiopian stronghold may also have less pairs than previously estimated.
Mitochondrial DNA fragment analyses detected reduced haplotype diversity in Southern Africa (4) compared with populations in the Northern Hemisphere (7.86). It further shows that South African and Ethiopian bearded vultures have limited genetic differentiation, suggesting that the species might be managed as a single entity across Africa.
However, although the mitochondrial DNA shows that birds from Southern Africa and Ethiopia share haplotypes, it is imperative to add nuclear markers to further explore whether connectivity between East and Southern Africa is on-going (gene flow), whether populations are inbred as well as whether nuclear diversity is similarly low.
The authors conclude that this level of reduced genetic diversity can be added to the threats to the species in Africa. Maintaining high levels of genetic diversity is essential for a species to survive. These low levels of diversity were most likely caused by the drastic range reduction experienced by the population over the past three centuries, more recently attributed to anthropogenic factors resulting in a low effective population size.
