Features of the use of ungulates by oxpeckers (Buphagus) in central Kenya

A detailed multi-year observational study of Red-Billed (RB) oxpecker (Buphagus erythrorhynchus) and yellow-billed (YB) oxpecker (B. Africanus) occurrence on a range of ungulate species was performed in two Kenyan national parks. Surprisingly observation of over 2100 individual Kongoni, in group sizes of 1 to > 50, revealed a total absence of oxpeckers, of either species, on Kongoni (Alcephalus buselaphus: subfamily Alcephalinae) in Nairobi National Park (NNP), although it was one of the most common bovid species present. There is no population of A. buselaphus at the second study site in central Kenya, Lake Nakuru National Park (LNNP). By contrast, the Impala (Aepyceros melampus), a smaller species, whose taxonomic status is phylogenetically ambiguous, but is widely considered to have evolved relatively recently in Africa, was a frequent oxpecker host in both NNP (29% of animals observed) and LNNP (12.9% of individual animals observed. Two species of gazelle Thompson’s gazelle (Gazella rufifrons)) and Grant’s gazelle (G. granti), subfamily Gazellinae, which were present in both parks but in relatively low abundance, were also not observed to host oxpeckers. The reason for these bovid subfamilies, apparently not being utilized as oxpecker hosts in central Kenya, is unclear and requires further research.