It seems as though the jury is still out on whether the oxpecker is a hero or a villain.
It is true that the oxpecker scavenges ticks off a wide variety of the larger African mammals, which is probably a good thing, but it also picks at any wounds or sores on the host animal to keep them open and bleeding, which is probably a bad thing. Indeed, the favourite food of the oxpecker is blood. Many of the ticks that it feeds on are engorged females, which have already fed on the blood of the host animal, and have therefore already caused whatever harm they are likely to cause in terms of drinking blood and spreading disease. Too late to help the host, but great for the oxpecker! The open wounds also provide access to all manner of infections. Although the relationship between the oxpecker and the hosts used to be considered of mutual benefit, there is a growing tendency to regard the bird as a parasite offering little benefit to the host.
Red-billed oxpeckers (Buphagus erythrorhynchus) are medium-sized passerines, with a length of about 20 cm. They have brown upperparts and heads, buff underparts and pale rumps. Their bills are red, the eyes are red or yellowish and they have yellow eye rings. They nest in holes in trees, which they line with the hair that they have plucked from their hosts. The females lay a clutch of two to five eggs, which hatch after an incubation period of around twelve days.
Yellow-billed oxpeckers (Buphagus africanus) are very similar in size and plumage colouration to the Red-billed variety, but have a yellow base to their red-tipped bill and a pale rump. They also lack the conspicuous yellow eye ring. Breeding habits are similar.
Sinners or saints, the oxpeckers are interesting little birds. They feed almost exclusively on the backs of larger mammals, not limiting themselves to a diet of ticks and blood, but also taking dead skin (finally a use for dandruff!!), mucus, saliva and even ear wax.
On a recent visit to the Kruger National Park in South Africa we witnessed Red-billed oxpeckers making themselves at home on a variety of different species. Some hosts appeared almost indifferent to their presence, whilst others tried actively to unsettle the birds by flicking their ears, swishing their tails, stamping their feet or generally making it difficult for them to retain their perches. The oxpeckers, for their part, seemed oblivious to the discomfort that they wrought as they pecked into the host’s ears (after that ear wax!) or perched on the host’s face.
Few of the larger animals seemed immune to the oxpecker’s attentions and they even settled on hippos as they emerged from the water.