Red-billed Oxpeckers subsists almost entirely on a diet of ticks and their larvae, maggots and other ecto-parasites, picked from the hides and orifices of large mammalian herbivores. They will however also peck at open wounds to feed on the blood. They are therefore closely associated with savannas and woodlands inhabited by good numbers of these large host animals, associating especially with the hairier game species like giraffes and antelope, as well as cattle and donkeys. Adults are about 20cm long and weigh around 50g.
At night, Red-billed Oxpeckers sleep in small flocks in trees, being especially fond of lalapalms. These birds nest in holes in trees lined with the fur of wild and domesticated mammals, particularly in the wet summer months. Usually there are three eggs in a clutch, incubated by both parents.
Red-billed Oxpeckers occur from Eritrea southwards to South Africa, where they can be found in the provinces of Kwazulu-Natal, Mpumalanga, Limpopo, Gauteng and Northwest, while an isolated population seems to have become established in the Eastern Cape as well. The eradication of wild game and the dipping of cattle has a detrimental impact on the food supply of the Red-billed Oxpecker, causing their populations outside protected areas to decline and, while the IUCN still views it as being of Least Concern, they are considered Near Threatened in South Africa and regularly reintroduced to reserves in areas from which they were previously exterminated.