Southern Yellow-billed Hornbill (Tockus leucomelas) [XC610219]
by Tony Archer from Near Zaakkuil Lodge, Hammanskraal, Limpopo, South Africa (call)
Southern Yellow-billed Hornbill (Tockus leucomelas) [XC516163]
by Dawie de Swardt from Polokwane Game Reserve, Polokwane, Limpopo, South Africa (flight call)
Subspecies
Sometimes considered to form a superspecies with Eastern Yellow-billed Hornbill (Tockus flavirostris) and in the past treated as conspecific, but differs in voice and bare-part colours. Both are closely related to Von der Decken's Hornbill (Tockus deckeni), and also, more distantly, to Monteiro's Hornbill (Tockus monteiri) and Red-billed Hornbill (Tockus erythrorhynchus), based on similar calls and behaviour, and DNA studies. Birds from Angola described as subspecies elegans, on basis of smaller size, paler plumage and differences in bare-part colours, and those from east of range as parvior, on basis of smaller size, but degree of variation in all populations uncertain. Further study is required.
The following 2 subspecies are recognised:
elegans Hartlaub, 1865 - South-western Angola.
leucomelas (Lichtenstein, MHK, 1842) - Arid savanna of south-central and southern Africa.
BirdLife International Species Factsheet