>Buphagus africanus of most of sub-Saharan Africa (Yellow-billed Oxpecker)

Yellow-billed Oxpecker

Yellow-billed Oxpecker
An adult bird in typical feeding mode
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Buphagidae/Sturnidae
Genus:	Buphagus
Species:	B. africanus
Binomial name
Buphagus africanus Linnaeus, 1766
Range of the Yellow-billed Oxpecker

The Yellow-billed Oxpecker, Buphagus africanus, is a passerine bird in the starling and myna family Sturnidae; some ornithologists regard the Oxpeckers to be a separate family, the Buphagidae (Zuccon, 2006). It is native to the savannah of sub-Saharan Africa from Senegal east to Sudan. It is least common in the extreme east of its range where it overlaps with the Red-billed Oxpecker, despite always dominating that species when feeding.

The Yellow-billed Oxpecker nests in tree holes lined with hair plucked from livestock. It lays 2–3 eggs. Outside the breeding season it is fairly gregarious, forming large, chattery flocks. Non-breeding birds will roost on their host animals at night.

The Yellow-billed Oxpecker eats insects and ticks. Both the English and scientific names arise from this species' habit of perching on large wild and domesticated mammals such as cattle and eating arthropod parasites. It will also perch on antelopes such as Wildebeest In a day an adult will take more than 100 engorged female Boophilus decoloratus ticks or 13,000 larvae.

However, their preferred food is blood, and while they may take ticks bloated with blood, they also feed on it directly (Feare 2003), pecking at the mammal's wounds. So the good the bird does to the mammal may be negated by its keeping the wounds open to parasites and disease. Whatever the net result, mammals generally tolerate oxpeckers (Feare 2003).

The Yellow-billed Oxpecker is 20 cm long and has plain brown upperparts and head, buff underparts and a pale rump. The feet are strong. The adults' bills are yellow and the base and red at the tip, while juveniles have brown bills. Its flight is strong and direct. The call is a hissy crackling krisss, krisss.

>Buphagus erythrorhynchus of east Africa (Red-billed Oxpecker)

Red-billed Oxpecker

Red-billed Oxpecker
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Buphagidae/Sturnidae
Genus:	Buphagus
Species:	B. erythrorhynchus
Binomial name
Buphagus erythrorhynchus Stanley, 1814
Range of the Red-billed Oxpecker

The Red-billed Oxpecker, Buphagus erythrorhynchus, is a passerine bird in the starling and myna family Sturnidae; some ornithologists regard the oxpeckers to be in a family by themselves, the Buphagidae. It is native to the savannah of sub-Saharan Africa, from the Central African Republic east to Sudan and south to northern and eastern South Africa. Its range overlaps that of the more dominant Yellow-billed Oxpecker.

The Red-billed Oxpecker nests in tree holes lined with hair plucked from livestock. It lays 2-5eggs with three being the average. Outside the breeding season it forms large, chattery flocks.

The Red-billed Oxpecker feeds on ticks found on other animals such as this Impala

The preferred habitat is open country, and the Red-billed Oxpecker eats insects. Both the English and scientific names arise from this species' habit of perching on large wild and domesticated mammals such as cattle and eating ticks. An adult will take nearly 100 engorged female Boophilus decoloratus ticks, or more than 12,000 larvae in a day.

However, their favorite food is blood, and while they may take on ticks bloated with blood, they also feed on it directly, pecking at the mammal's wounds to keep them open to more parasites. So, what good the bird does for the mammal is negated by it keeping the wounds open to parasites and disease.

This is a medium-sized passerine, 20 cm long with strong feet. The Red-billed Oxpecker has plain brown upperparts and head, buff underparts and a pale rump. The bill is red, and adults have a yellow eyering, both clear distinctions from the related Yellow-billed Oxpecker. Its flight is strong and direct, and the call is a hissy crackling trik-quisss.

>>>Buphagidae (Oxpecker)

Oxpecker

Oxpeckers
Red-billed Oxpecker
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Suborder:	Passeri
Family:	Buphagidae Lesson, 1828
Genus:	Buphagus Brisson, 1760
Species
Buphagus africanus Buphagus erythrorhynchus

The oxpeckers are two species of bird which make up the family Buphagidae. Some ornithologists regard them as a subfamily Buphaginae within the starling family Sturnidae but they appear to be quite distinct.Oxpeckers are endemic to the savanna of Sub-Saharan Africa. Both the English and scientific names arise from their habit of perching on large mammals (both wild and domesticated) such as cattle or rhinoceroses, and eating ticks, botfly larvae, and other parasites.

According to the more recent studies of Muscicapoidea phylogeny,the oxpeckers are an ancient line related to Mimidae (mockingbirds and thrashers) and starlings but not particularly close to either. Considering the known biogeography of these groups, the most plausible explanation seems that the oxpecker lineage originated in Eastern or Southeastern Asia like the other two.This would make the two species of Buphagus something like living fossils, and elegantly demonstrates that such remnants of past evolution can possess striking and unique autapomorphic adaptations.

Distribution and habitat

The oxpeckers are endemic to sub-Saharan Africa, where they occur in most open habitats. They are absent from the driest deserts and the rainforests. Their distribution is restricted by the presence of their preferred prey, specific species of ticks, and the animal hosts of those ticks. Over much of East Africa the two species are sympatric (have overlapping distribution) and may even occur on the same host animal. The nature of the interactions between the two species is unknown.

Behaviour

Oxpeckers are fairly gregarious.

Diet and feeding

Yellow-billed Oxpecker on a wildebeest

Oxpeckers feed exclusively on the backs of large mammals. Certain species are seemingly preferred, whereas others, like the Lichtenstein's hartebeest or Topi are generally avoided. Smaller antelope such as lechwe, duikers and reedbuck are also avoided, the smallest regularly used species is the Impala, probably because of the heavy tick load and social nature of that species. In many parts of their range they now feed on cattle, but avoid camels. They feed on ectoparasites, particularly ticks, as well as insects infecting wounds and the flesh and blood of some wounds as well.

Oxpecker/mammal interactions are the subject of some debate and ongoing research. They were originally thought to be an example of mutualism, but recent evidence suggests that oxpeckers may be parasites instead.Oxpeckers do eat ticks, but often the ticks have already fed on the ungulate host and there has been no proven statistically significant link between oxpecker presence and reduced ectoparasite load.However one study of impalas found that impalas which were used by oxpeckers spent less time grooming themselves suggesting a reduction in parasite load. Oxpeckers have been observed to open new wounds and enhance existing ones in order to drink the blood of their perches.Oxpeckers also feed on the earwax and dandruffs of mammals, although less is known about the benefits of this to the mammal, it is suspected that this is also a parasitic behaviour.Some oxpecker hosts are intolerant of their presence.Elephants and some antelope will actively dislodge the oxpeckers when they land. Other species tolerate oxpeckers while they search for ticks on the face, what one author described as "appears ... to be an uncomfortable and invasive process.

Breeding

The breeding season of the oxpeckers, in at least one location, is linked to the rainy season, which affects the activity of their mammalian hosts and the tick loads of those hosts. Both courtship and copulation occur on their hosts as well. They nest in holes, usually in trees but sometimes in other types of cavity, including holes in walls. The nests are lined with grasses and also often with hair plucked from their hosts and even livestock such as sheep which are not usually used. The typical clutch is between two to three eggs, but the Red-billed Oxpecker may lay up to five eggs.

Species

• Red-billed Oxpecker, Buphagus erythrorhynchus of east Africa.
• Yellow-billed Oxpecker, Buphagus africanus of most of sub-Saharan Africa.