Eric Baccega / Four Burchell's zebra (Equus quagga burchellii) two with Red billed oxpeckers (Buphagus erythrorynchus) on their backs, with Antelope, mainly Impala (Aepyceros melampus) and a Warthog (Phacochoerus af...

Jen Guyton / Common eland (Taurotragus oryx) with Red-billed oxpeckers (Buphagus erythrorhynchus) and yellow-billed oxpecker (Buphagus africanus) standing on the savanna in the Maasai Mara Reserve, Kenya.

Ann & Steve Toon / Redbilled oxpecker (Buphagus erythrorhynchus), Zimanga private game reserve, KwaZulu-Natal, South Africa, June

Denis-Huot / Greater kudu (Tragelaphus strepsiceros) female with Red-billed oxpecker (Buphagus erythrorhynchus), Sabi Sands Private Game Reserve, South Africa.

Ernie Janes / Impala (Aepyceros melampus) with Red-billed oxpecker (Buphagus erythrorhynchus) , KwaZulu-Natal, South Africa.

Wim van den Heever / Red-Billed oxpecker (Buphagus erythrorhynchus) having a drink, taken from eye level hide, Zimanga Private Game Reserve, South Africa

Will Burrard-Lucas / Rhodesian / Thornicroft giraffe (Giraffa camelopardalis thornicrofti) portrait, with Red-billed oxpeckers (Buphagus erythrorhynchus) on neck, South Luangwa National Park, Zambia, April.

Pete Oxford / Giraffe (Giraffa camelopardalis) with Red billed oxpecker (Buphagus erythrorhynchus) on head, Marakele Private Reserve, Waterberg Biosphere Reserve, Limpopo Province, South Africa.

Konrad Wothe / Red billed oxpecker (Buphagus erythrorhynchus) perched on Reticualted giraffe (Giraffa camelopardalis reticulata) neck, Samburu Game Reserve, Kenya, East Africa, August.

Konrad Wothe / Red billed oxpecker (Buphagus erythrorhynchus) perched on Reticualted giraffe (Giraffa camelopardalis reticulata) neck, Samburu Game Reserve, Kenya, East Africa, August.

Ann & Steve Toon / Warthog (Phacochoerus aethiopicus), with adult and juvenile Redbilled oxpeckers (Buphagus erythrorhynchus) Mkhuze Game Reserve, KwaZulu-Natal, South Africa, June

Ann & Steve Toon / Red-billed oxpecker (Buphagus erythrorhynchus), Zimanga Private Game Reserve, KwaZulu-Natal, South Africa, May

Richard Du Toit / Red-billed oxpecker (Buphagus erythrorhynchus) on back of South African giraffe (Giraffa camelopardalis giraffa), Itala Game Reserve, KwaZulu-Natal.

Denis-Huot / African buffalo (Syncerus caffer) male with red-billed oxpecker (Buphagus erythrorhynchus), Masai Mara Game Reserve, Kenya, October.

Ann & Steve Toon / Hippopotamus (Hippopotamus amphibius) group on land with red billed oxpeckers (Buphagus erythrorhynchus), Kruger National park, Mpumalanga, South Africa.

Charlie Summers / Masai giraffe (Giraffa camelopardalis tippelskirchi) male with red-billed (Buphagus erythrorhynchus) and yellow-billed (Buphagus africanus) oxpeckers on neck, Ruaha National Park, Tanzania.

Pal Hermansen / Black rhinceros (Diceros bicornis) and Red-billed oxpeckers (Buphagus erythrorhynchus) Masai Mara, Kenya.

Denis-Huot / Red-billed oxpecker (Buphagus erythrorhynchus) on a White rhino (Ceratotherium simum) Kruger National Park, South Africa

Denis-Huot / Red-billed oxpecker (Buphagus erythrorhynchus) on a buffalo, Nakuru National Park, Kenya

Denis-Huot / Grant's zebra (Equus burchelli boehmi) mother with foal, watching the Red billed oxpecker (Buphagus erythrorhynchus) on its mother's back, Nakuru National Park, Kenya

Denis-Huot / Hippo (Hippopotamus amphibius) mother and newborn, with red billed oxpecker (Buphagus erythrorhynchus) on mother's ear. Masai-Mara Game Reserve, Kenya. Vulnerable species.

Denis-Huot / African buffalo (Syncerus caffer) male and Red-billed oxpecker (Buphagus erythrorhynchus) Nakuru National Park, Kenya

Richard Du Toit / Greater Kudu (Tregalaphus strepsiceros) covered in Red-billed Oxpecker birds (Buphagus erythrorhynchus) Mpumalanga Province, South Africa, June 2012

Richard Du Toit / Impala (Aepyceros melampus) male with Red-billed Oxpecker (Buphagus erythrorhynchus) on head and back, Mpumalanga Province, South Africa, June 2012

Richard Du Toit / Impala (Aepyceros melampus) rear view of male with Red-billed Oxpecker (Buphagus erythrorhynchus) on neck and back, Mpumalanga Province, South Africa, June 2012

Oriol Alamany / Giraffe (Giraffa camelopardalis giraffa) with Red-billed Oxpecker (Buphagus erythrorhynchus), bending to drink at a waterhole, Kruger National Park, Transvaal, South Africa, September.

Ann & Steve Toon / Giraffe (Giraffa camelopardalis) with Red billed oxpecker (Buphagus erythrorhynchus) iMfolozi game reserve, KwaZulu Natal, South Africa

Ann & Steve Toon / Cape buffalo (Syncerus caffer) with Red billed oxpecker (Buphagus erythrorhynchus) Hluhluwe-iMfolozi Park, Kwazulu Natal, South Africa

Christophe Courteau / Redbilled oxpecker (Buphagus erythrorhynchus) on chest of an Impala, South Africa, June

Christophe Courteau / Redbilled oxpecker (Buphagus erythrorhynchus) on back of an Impala, South Africa, June

Ann & Steve Toon / Redbilled Oxpecker (Buphagus erythrorhynchus) on an Impala (Aepyceros melampus) Kruger National Park, South Africa

Ann & Steve Toon / Redbilled Oxpecker (Buphagus erythrorhynchus) removing ticks from face of an Impala (Aepyceros melampus) Kruger National Park, South Africa

Patricio Robles Gil / Red billed oxpeckers {Buphagus erythrorhynchus} on back of Impala, Kruger NP, South Africa

Patricio Robles Gil / Red billed oxpecker {Buphagus erythorhynchus} searching for ticks on leg of Impala, Kruger NP, South Africa

David Noton / Red billed oxpecker (Buphagus erythrorhynchus) perched on the nose of African buffalo (Syncerus caffer) Kruger National Park, South Africa

Mary McDonald / Reticulated giraffe {Giraffa camelopardalis reticulata}shaking off Red-billed oxpecker {Buphagus erythrorhynchus} Samburu reserve, Kenya, Note white ear of the giraffe

Gabriel Rojo / RF- Red billed oxpecker (Buphagus africanus) on Common Zebra (Equus burchelli). Kruger National Park, South Africa. (This image may be licensed either as rights managed or royalty free.)

WILLIAM OSBORN / Male Impala (Aepyceros melamous) portrait with red-billed Oxpecker, Kruger NP, South Africa

WILLIAM OSBORN / Young female Impala (Aepyceros melampus) with juvenile Red-billed oxpecker feeding on wound on ear, Kruger NP, South Africa

Paul Hobson / Red Billed Oxpecker {Buphagus erythorhynchus} on buffalo head, Nakuru, Kenya.

Paul Hobson / Red Billed Oxpeckers {Buphagus erythorhynchus} on buffalo head, Nakuru, Kenya.

Richard Du Toit / Red billed oxpecker (Buphagus erythrorhynchus) perched on Water buffalo nose (Synceros caffer), Sabi Sand Game Reserve, South Africa

Philippe Clement / Red billed oxpeckers {Buphagus erythrorhynchus} on Impala Kruger NP S Africa

Richard Du Toit / Red billed oxpecker {Buphagus erythrorhynchus} on Hippopotamus. Botswana

Anup Shah / Head of African Buffalo with Red-billed Oxpecker birds {Syncerus caffer}

Richard Du Toit / Red billed oxpecker on giraffe {Buphagus erythrorhynchus} Kruger NP, South Africa.

Richard Du Toit / Red billed oxpecker looking for insects on Buffalo. Mala Mala GR, South Africa.

Richard Du Toit / Impala (Aepyceros melampus) with red-billed oxpecker Kruger NP South Africa