John Waters / Southern Yellow billed Hornbill {Tockus leucomelas} Kalahari Desert, Northern Cape, South Africa

Andrew Parkinson / Yellow billed hornbill {Tockus flavirostris} Etosha NP, Namibia

Tony Heald / Bradfield's Hornbill (Tockus bradfieldi) portrait, Hwange National Park, Zimbabwe October 2012

Christophe Courteau / Portrait of a Southern yellow billed hornbill {Tockus leucomelas}, Okavango Delta, Botswana.

Robin Chittenden / Red-billed Hornbill (Tockus erythrorhynchus erythrorhynchus) Western Division, Gambia, March

Robin Chittenden / African grey hornbill (Tockus nasutus) in flight, Gambia, February

Charlie Summers / Red-billed hornbill (Tockus erythrorhynchus) feeding its mate who is sealed in its nest in the tree. This nest had a front door and a back door, one door is where the male is feeding the female and an...

Charlie Summers / Male African Gray Hornbill (Tockus nasutus), portrait. Tanzania.

Richard Du Toit / Red-billed Hornbill (Tockus erythrorhynchus). Kruger National Park, South Africa, August.

Brent Stephenson / Southern Yellow-billed Hornbill (Tockus leucomelas) perched in a shrub in evening light. Kruger National Park, South Africa, January.

Tui De Roy / Von der Decken's Hornbill (Tockus deckeni), Mpala Research Centre, Kenya

Tui De Roy / Red-billed Hornbill (Tockus erythrorhynchus) calling, Mpala Research Centre, Kenya

Tui De Roy / Red-billed Hornbill (Tockus erythrorhynchus), Lewa Wildlife Conservation Area, Kenya

Mary McDonald / Yellow-billed Hornbill (Tockus flavirostris) perched in tree, Samburu Game Reserve, Kenya

Tui De Roy / Von der Decken's Hornbill (Tockus deckeni) lifelong pair sharing food, Mpala Research Centre, Laikipia, Kenya

Tui De Roy / Von der Decken's Hornbill (Tockus deckeni) female eating nestling, Mpala Research Centre, Laikipia, Kenya

Tui De Roy / Von der Decken's Hornbill (Tockus deckeni) lifelong pair sharing food, Mpala Research Centre, Laikipia, Kenya

Sergey Gorshkov / Red-billed Hornbill (Tockus erythrorhynchus), Botswana

ZSSD / White-crested Hornbill (Tockus albocristatus), native to Africa

Stephen Dalton / Red-billed hornbill (Tockus erythrorhynchus) perched on Acacia, Africa

Chris Gomersall / Male Southern yellow billed hornbill (Tockus leucomelas) perched in acacia tree, Etosha National Park, Namibia, November

Chris Gomersall / Damara hornbill (Tockus erythrorhynchus damarensis) perched on branch, Hobatere, Namibia, November

Kim Taylor / Monteiro's hornbill (Tockus monteiri) on ground, Namibia, Africa

Kim Taylor / Monteiro's Hornbill (Tockus monteiri) portrait, Namibia, Africa

Mary McDonald / Red-billed hornbill {Tockus erythrorhynchus} courtship display, Samburu reserve, Kenya

Suzi Eszterhas / Yellow-billed hornbill {Tockus flavirostris} Sarara Camp, Namunyak Conservancy, Northern Rangelands, Kenya

Suzi Eszterhas / Red-billed hornbill {Tockus erythrorhynchus} Sarara Camp, Namunyak Conservancy, Northern Rangelands, Kenya

Tim Laman / African crowned hornbill (Tockus alboterminatus) perched in the forest canopy, Kibale National Park, Uganda

Tim Laman / Red-billed hornbill (Tockus erythrorhynchus) at nest hole, Kruger NP, South Africa

Tim Laman / Southern yellow-billed hornbill (Tockus leucomelas) perched on rock, with Impala in background. Kruger National Park, South Africa.

Tim Laman / Southern yellow-billed hornbill (Tockus leucomelas) perched on thorn bush. Kruger National Park, South Africa.

Tim Laman / Red-billed hornbill (Tockus erythrorhynchus) chick peering out of nest hole, its first step toward emerging into the outside world, Africa

Tim Laman / Red-billed hornbill (Tockus erythrorhynchus) on ground holding a beetle in its beak. Kruger National Park, South Africa.

Suzi Eszterhas / Red-billed Hornbill (Tockus erythrorhynchus), Sarara Camp, Namunyak Wildlife Conservancy, Kenya

Suzi Eszterhas / Eastern Yellow-billed Hornbill (Tockus flavirostris), Sarara Camp, Namunyak Wildlife Conservancy, Kenya

Suzi Eszterhas / Red-billed Hornbill (Tockus erythrorhynchus), Sarara Camp, Namunyak Wildlife Conservancy, Kenya

Jouan & Rius / Southern Yellow billed Hornbill (Tockus leucomelas) Etosha NP, Namibia

John Waters / Southern Yellow-billed Hornbill {Tockus leucomelas} Kalahari Desert, Northern Cape, South Africa

Richard Du Toit / Southern Yellow-billed Hornbill (Tockus leucomelas) portrait, Savuti, Chobe National Park, Botswana

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} Kruger National Park, South africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} Kruger National Park, South Africa

Gabriel Rojo / African grey hornbill {Tokus nasutus} Kruger NP, South Afica

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} preening, Kruger National Park, South Africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} Kruger National Park, South africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} preening, Kruger National Park, South Africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} preening, Kruger National Park, South Africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} preening, Kruger National Park, South Africa

Gabriel Rojo / Southern yellow billed hornbill {Tockus leucomelas} preening, Kruger National Park, South Africa

Michael Hutchinson / Red-billed hornbill {Tockus erythrorhynchus} on ground, Lewa Downs, Kenya.

Peter Blackwell / African grey hornbill (Tockus nasutus) perched on Acacia branch, Lake Naivasha NP, Kenya

Jabruson / Red billed hornbill at nest hole in tree {Tockus erythrorhynchus} Tsavo East NP, Kenya

Anup Shah / Von der Deckens hornbill {Tockus deckeni} Serengeti NP, Tanzania

WILLIAM OSBORN / Redbilled hornbill {Tockus erythrorhynchus} Kruger NP, South Africa

David Shale / Southern yellow billed hornbill {Tockus leucomelas} Kruger NP, South Africa

Hanne & Jens Eriksen / Red billed Hornbill {Tockus erythrorhynchus} Kruger NP, South Africa.

Pete Oxford / Yellow Billed Hornbill {Tockus flavirostris} Moremi Wildlife Reserve Okavango, Botswana.

Jabruson / Von Der Deckens Hornbill {Tockus deckeni} with dung and mongooses on termite mound, Tsavo NP, Kenya.

Jabruson / Red-Billed Hornbill {Tockus erythrorhynchus} with elephant dung and mongooses on termite mound, Tsavo East NP, Kenya, East Africa

Jeff Vanuga / Yellow billed hornbilll {Tockus flavirostris} Samburu National Reserve, Kenya, Africa.

Jabruson / Von der deckens hornbill {Tockus deckeni} with Quela chick taken from nest, Tsavo East NP, Kenya

Tony Heald / Rear view of Von der Deckens hornbill {Tockus deckeni} male, Laikipia, Kenya.

Tony Heald / Yellow billed hornbill feeds on fruit (Tockus flavirostris) Etosha NP Namibia

Andrew Parkinson / Yellow billed hornbill {Tockus flavirostris} Etosha NP, Namibia

Hermann Brehm / African grey hornbill {Tockus nasutus} Botwsana

Luiz Claudio Marigo / Von der Deckens hornbill {Tockus deckeni} Samburu NR, Kenya

Jabruson / Red billed hornbill at nest hole {Tockus erythrorhynchus} Tsavo East NP, Kenya

Richard Du Toit / Eastern Yellow-billed Hornbill (Tockus flavirostris) adult arriving at nest hole with food for young, summer, Chobe National Park, Botswana

Richard Du Toit / Yellow billed hornbill flying to nest hole {Tockus flavirostris} Botswana

Richard Du Toit / Yellow billed hornbill {Tockus flavirostris}profile portrait, Malamala GR, South Africa

Richard Du Toit / Yellow billed hornbill display {Tockus flavirostris} Moremi WR, Botswana

Paul Hobson / Southern yellow billed hornbill {Tockus leucomelas} Namibia

Richard Du Toit / Male Red billed hornbill at nest hole in tree, Botswana, Chobe NP.

Richard Du Toit / Yellow billed hornbill {Tockus flavirostris} Etosha NP, Namibia.

Richard Du Toit / Yellow billed hornbills {Tockus flavirostris} Etosha NP, Namibia.

Richard Du Toit / Yellow billed hornbill (Tockus flavirostris) Botswana Moremi WR.

Richard Du Toit / Yellow billed hornbill (Tockus flavirostris. Moremi reserve, Botswana, Southern Africa

Peter Blackwell / Red billed hornbill portrait {Tockus erythrorhynchus} Samburu Reserve, Kenya, East Africa

Richard Du Toit / Bradfield's hornbill {Tockus bradfieldi} Chobe NP, Botswana

Jabruson / D - Red billed hornbill {Tockus erythrorhynchus} + Dwarf mongooses {Helogale parvula} on termite mound. Tsavo East NP, Kenya

Jabruson / Dwarf mongoose {Helogale parvula} group inhabit termite mound, male Von der Deckens hornbill {Tockus deckeni} waits for mongooses to leave mound Tsavo East NP, Kenya

Jabruson / Dwarf mongoose {Helogale parvula} group inhabit termite mound and Red billed hornbill {Tockus erythrochynchus} Tsavo East NP, Kenya

Jabruson / Male Von der Deckens hornbill {Tockus deckeni} feeding on Red billed quelea chick {Quelea quelea} Tsavo East NP, Kenya

Tony Heald / Yellow billed hornbill {Tockus flavirostris} Moremi WR, Botswana, Africa

Murray Cooper / Red-billed Hornbill (Tockus erythrorhynchus), South Africa

Onne van der Wal / Southern yellow-billed hornbill (Tockus leucomelas) perched on tree branch, Motswari private game reserve, northern South Africa.

Richard Du Toit / Southern Yellow-billed Hornbill (Tockus leucomelas) feeding on insect, Limpopo, South Africa

Mike Read / African grey hornbill {Tockus nasutus} perched, Kruger NP, South Africa

Mike Read / African grey hornbill {Tockus nasutus} perched, Kruger NP, South Africa

Mike Read / African crowned hornbill {Tockus alboterminatus} perched in tree, Umfolozi Game Reserve, South Africa

Andrew Parkinson / Yellow billed hornbill {Tockus flavirostris} Kgalagadi TFP S Africa Transfrontier