Richard Du Toit / Greater kudu (Tregalaphus strepsiceros) covered in Yellowbilled oxpeckers (Buphagus africanus) rear view, Kruger National Park, South Africa.

Sharon Heald / Yellowbilled oxpecker {Buphagus africanus} on Zebra Moremi WR, Botswana, Africa

Neil Aldridge / Two Black rhinoceros (Diceros bicornis) feed on bushes in Okavango Delta, Botswana, while Yellowbilled oxpeckers (Buphagus africanus) feeding on parasites on their skins. These rhinos were released in...

Francois Savigny / Southern yellowbilled hornbill {Tockus leucomelas} perching on branch with beak open, Kruger NP, South Africa

Ann & Steve Toon / Southern yellowbilled hornbills (Tockus leucomelas) courtship display. Kruger National Park, South Africa. September.

Ann & Steve Toon / Yellowbilled stork (Mycteria ibis) foraging, Zimanga private Game Reserve, KwaZulu-Natal, South Africa, May

Ann & Steve Toon / Yellowbilled stork (Mycteria ibis) reflected in water, Zimanga private Game Reserve, KwaZulu-Natal, South Africa, May

Richard Du Toit / Yellowbilled stork (Mycteria ibis) in flight, close up of face and beak, Kruger National Park, South Africa.

Richard Du Toit / Yellowbilled duck (Anas undulata) flock, flying in a row, Marievale Bird Sanctuary, Gauteng Province, South Africa. June.

Richard Du Toit / Yellowbilled oxpecker (Buphagus africanus) on the back of Greater kudu (Tregalaphus strepsiceros) Kruger National Park, South Africa.

Richard Du Toit / Yellowbilled oxpecker (Buphagus africanus) group of three of Buffalo, back of Kruger National Park, South Africa.

Martin Willis / Intermediate Egret (Mesophoyx intermedia) with prey, Wyndham, Kimberley, Western Australia, Australia

Richard Du Toit / Yellowbilled Kites (Milvus aegyptius) in flight, Kruger National Park, Limpopo Province, South Africa, September.

Rob Drummond / Intermediate Egret (Mesophoyx intermedia) wading, Queensland, Australia

Simon Bennett / Intermediate Egret (Mesophoyx intermedia), Queensland, Australia

Hermann Brehm / African buffalo (Syncerus caffer) with Yellowbilled oxpecker (Buphagus africanus) Masai Mara GR, Kenya

Ann & Steve Toon / Yellowbilled kite (Milvus migrans aegyptius) perched on branch, Hluhluwe Umfolozi Park, South Africa

Winfried Wisniewski / Intermediate Egret (Mesophoyx intermedia) back-lit in field, native to Asia and Australia

Mike Wilkes / Yellowbilled stork wading, Lake Baringo, Kenya, East Africa

Richard Du Toit / Yellowbilled stork {Mycteria ibis}, Moremi Wildlife Reserve, Botswana, South Africa.

Peter Blackwell / Yellowbilled stork feeding, Masai Mara, Kenya, East Africa

Richard Du Toit / Warthog male {Phacochoerus aethiopicus} with Yellowbilled oxpecker birds {Buphagus africanus} Botswana SavuteChobe NP. Southern Africa

Richard Du Toit / Warthog male {Phacochoerus aethiopicus} + Yellowbilled oxpecker birds {Buphagus africanus} Botswana SavuteChobe NP. Southern Africa

Sharon Heald / Yellowbilled oxpecker {Buphagus africanus} on Zebra Moremi NR, Botswana, Southern Africa

Tony Heald / Yellowbilled stork, Moremi NP, Botswana, Southern Africa

Francois Savigny / Southern yellow billed hornbill {Tockus leucomelas} Kruger NP South Africa