Anup Shah / Nile crocodile holding newly hatched young in mouth {Crocodylus niloticus} Kenya

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Neil Aldridge / Nile crocodile (Crocodylus niloticus) snatching a Mozambique tilapia (Oreochromis mossambicus) in its jaws, Shingwedzi River, Kruger National Park, South Africa.

Neil Aldridge / Nile crocodile (Crocodylus niloticus) resting in the sun on a grassy island in the middle of the Chobe River, northern Botswana.

Wim van den Heever / Nile crocodile (Crocodylus niloticus) still in the fast flowing water of the Mara River, taken with slow shutter speed. Masai Mara, Kenya.

Charlie Summers / Nile crocodile (Crocodylus niloticus) making its way through sand to the Rufiji River, Selous Game Reserve, Tanzania.

Denis-Huot / Starving group of Nile crocodiles (Crocodylus niloticus) feeding on Zebra, Masai-Mara game reserve, Kenya.

Denis-Huot / Nile crocodile (Crocodylus niloticus) lunging at Thomson's gazelle (Eudorcas thomsonii) in water, Mara river, Masai-Mara game reserve, Kenya.

Martin Dohrn / Thermal camera image of hippos (Hippopotamus amphibius), crocodile (Crocodylus niloticus) and wildebeest (Connochaetes taurinus, far left) on the banks of the Mara River, Masai Mara, Kenya. Image take...

Anup Shah / Nile crocodile (Crocodylus niloticus) emerging from the Mara River - wide angle perspective, Masai Mara National Reserve, Kenya. August 2009.

Anup Shah / Nile crocodile (Crocodylus niloticus) emerging from the Mara River - wide angle perspective, Masai Mara National Reserve, Kenya. August 2009.

Anup Shah / Nile crocodiles (Crocodylus niloticus) competing over a wildebeest carcass. Masai Mara National Reserve, Kenya, August 2009

Anup Shah / Nile crocodile (Crocodylus niloticus) attacking a Thomson's gazelle (Eudorcas thomsonii) as it crosses the Mara River. Masai Mara National Reserve, Kenya, October 2009

Anup Shah / Nile crocodile (Crocodylus niloticus) attacking a Thomson's gazelle (Eudorcas thomsonii) as it crosses the Mara River. Masai Mara National Reserve, Kenya, October 2009

Anup Shah / Nile crocodile (Crocodylus niloticus) attacking a Wildebeest (Connochaetes taurinus) as it crosses the Mara River. Masai Mara National Reserve, Kenya, October 2009

Anup Shah / Nile crocodile (Crocodylus niloticus) attacking a Wildebeest (Connochaetes taurinus) as it crosses the Mara River. Masai Mara National Reserve, Kenya, September 2009

Ann & Steve Toon / Head portrait of Nile crocodile (Crocodylus niloticus) partically submerged, Crocodile Centre, St Lucia, KwaZulu Natal, South Africa. Captive

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) with jaws wide open, Kruger National Park, South Africa

Philip Dalton / Nile Crocodile (Crocodylus niloticus) approaching Common Zebra (Equus burchellii) as it swims across Mara river during migration, Masai Mara GR, Kenya

Philip Dalton / Nile Crocodile (Crocodylus niloticus) grabbing Common Zebra (Equus burchellii) as it swims across Mara river during migration, Masai Mara GR, Kenya

Philip Dalton / Nile Crocodile (Crocodylus niloticus) approaching Common Zebra (Equus burchellii) mother and foal as they swim across Mara river during migration, Masai Mara GR, Kenya

Philip Dalton / Nile Crocodile (Crocodylus niloticus) grabbing Common Zebra (Equus burchellii) as it swims across Mara river during migration, Masai Mara GR, Kenya

Andy Rouse / Common wildebeest (Connochaetes taurinus) on migration with Nile crocodile (Crocodylus niloticus) waiting in water, Masai Mara, Kenya

Andy Rouse / Nile crocodile (Crocodylus niloticus) chasing Wildebeest (Connochaetes taurinus) during migration crossing, Masai Mara, Kenya, Africa

Edwin Giesbers / Nile crocodile (Crocodylus niloticus) partially submerged at night, captive, Madagascar

Edwin Giesbers / Nile Crocodile (Crocodylus niloticus) close-up of top of head, captive, Madagascar

Anup Shah / Nile crocodile {Crocodylus niloticus} close up of mouth and teeth, Serengeti NP, Tanzania

Anup Shah / Nile crocodile {Crocodylus niloticus} lunges for Wildebeest {Connochaetes taurinus} which leaps out of its reach, Grumeti river, Serengeti NP, Tanzania

Anup Shah / Wildebeest {Connochaetes taurinus} climbing out of river to escape the jaws of a Nile crocodile {Crocodylus niloticus} Masai Mara GR, Kenya

Jabruson / Nile crocodile eye close up {Crocodylus niloticus} Murchison Falls NP, Uganda

Anup Shah / Nile crocodile {Crocodylus niloticus} eating Thompsons gazelle in Mara river, Masai Mara, Kenya.

Anup Shah / Nile Crocodile {Crocodylus Niloticus} spin feeding zebra carcass, Mara River, Masai Mara, Kenya.

Anup Shah / Hippoptamus {Hipopotamus amphibius} with Nile Crocodile {Crocodylus Niloticus} in the background. Mara River, Masai Mara, Kenya.

Anup Shah / Nile Crocodile {Crocodylus Niloticus} Grumeti River, Serengeti, Tanzania

Anup Shah / Nile Crocodile {Crocodylus niloticus} attacking Wildebeest {Connochaetes taurinus} Mara river, Masai Mara NR, Kenya.

Anup Shah / Nile Crocodile {Crocodylus Niloticus} attacking Wildebeest on the banks of the Grumeti River, Serengeti, Tanzania.

Anup Shah / Curious Hippoptamus {Hipopotamus amphibius} and basking Nile Crocodile {Crocodylus Niloticus} Mara River, Masai Mara, Kenya.

Anup Shah / Nile crocodile hatching from egg {Crocodylus niloticus} Kenya

Anup Shah / Nile crocodile using teeth to help crack egg open for hatchling {Crocodylus niloticus} Kenya

Anup Shah / Newly hatched Nile crocodile held in parent's mouth {Crocodylus niloticus} Kenya

Jim Brandenburg / Nile Crocodile (Crocodylus niloticus) thermoregulating, Caprivi Strip, Namibia

Jim Brandenburg / Nile Crocodile (Crocodylus niloticus) mouth defense displaying, South Africa

Jim Brandenburg / Nile Crocodile (Crocodylus niloticus) thermoregulating, Caprivi Strip, Namibia

Anup Shah / Zebra kicks out at attacking Nile crocodile {Crocodylus niloticus} Mara river, Masai Mara, Kenya

Anup Shah / Nile crocodile {Crocodylus niloticus) lunging at Wildebeest calf. Masai river Kenya

Peter Blackwell / Nile crocodile attacking Wildebeest crossing River Mara, Kenya, Africa

TJ Rich / Nile crocodile attempting to take zebra during crossing of Mara river {Crocodylus niloticus} Masai Mara, Kenya

Jabruson / Nile crocodile (Crocodylus niloticus) hatching from egg. Murchison Falls NP, Uganda, East Africa

Jabruson / Nile crocodile hatching from egg, Murchison Falls NP, Uganda

Anup Shah / Nile crocodile {Crocodylus niloticus} with zebra prey in Mara River, Kenya,

Anup Shah / Nile crocodile attacking zebra in water.(Crocodylus niloticus)

Anup Shah / Nile crocodile hatching from egg {Crocodylus niloticus} C Kenya

Anup Shah / Nile crocodile using teeth to help open egg for young hatchling {Crocodylus niloticus} Kenya

Anup Shah / Nile crocodile attacking Wildebeest crossing river during migration, Masai Mara, Kenya

Eric Baccega / Nile crocodile (Crocodylus niloticus) attacking a Wildebeest (Connochaetes taurinus) as it crosses the Mara River. Masai Mara National Reserve, Kenya.

Hanne & Jens Eriksen / Nile rat (Arvicanthus niloticus) feeding on vegetation. Oman, March.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus), Zimanga game reserve, KwaZulu-Natal, South Africa.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus), Chobe river, Botswana.

Tony Heald / Nile crocodile (Crocodylus niloticus) basking on rock near river rapids. Kruger National Park, South Africa.

John Shaw / Yellow-billed stork (Mycteria ibis) watching a Nile crocodile (Crocodylus niloticus). Chobe RIver near Kasane, Botswana, September.

Suzi Eszterhas / Nile crocodile (Crocodylus niloticus), tail above water. Sabi Sands Game Reseve, South Africa.

Ann & Steve Toon / Water monitor (leguaan) (Varanus niloticus), Zimanga private game reserve, KwaZulu-Natal, South Africa, September

Sandesh Kadur / Nile monitor lizard (Varanus niloticus). Lake Manyara National Park, Tanzania.

Piotr Naskrecki / Giant Water Bug (Lethocerus niloticus) feeding on fish prey, Gorongosa National Park, Mozambique

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) at night, Zimanga private game reserve, KwaZulu-Natal, South Africa.

Bernard Castelein / Nile monitor (Varanus niloticus), Gambia.

Bernard Castelein / Nile monitor (Varanus niloticus), Gambia.

Guy Edwardes / Lion (Panthera leo), pair feeding on Monitor lizard (Varanus niloticus), edge of Chobe River, Botswana.

Jen Guyton / Nile crocodile (Crocodylus niloticus) at water's edge with Great white pelican (Pelecanus onocrotalus) prey, and other crocodiles nearby trying to steal the prey. Msicadzi River, Gorongosa National Pa...

Jen Guyton / Nile crocodile (Crocodylus niloticus) at water's edge to feed on Great white pelican (Pelecanus onocrotalus) prey. With birds on the shore including pink-backed pelicans (Pelecanus rufescens), marabou...

Jen Guyton / Nile crocodile (Crocodylus niloticus) with Great white pelican (Pelecanus onocrotalus) prey. Other birds watch from the shore, including great egrets (Ardea alba), grey herons (Ardea cinerea) and hame...

Jen Guyton / Nile crocodile (Crocodylus niloticus) catching a Great white pelican (Pelecanus onocrotalus) prey, Msicadzi River, Gorongosa National Park, Mozambique. During the dry season many water sources dry up...

Jen Guyton / Nile crocodiles (Crocodylus niloticus) fighting over Great white pelican (Pelecanus onocrotalus) in the Msicadzi River, Gorongosa National Park, Mozambique. During the dry season many water sources...

Jen Guyton / Nile crocodile (Crocodylus niloticus) eating Great white pelican (Pelecanus onocrotalus). With birds on the shore including pink-backed pelicans (Pelecanus rufescens), marabou storks (Leptoptilos crum...

Jen Guyton / Nile crocodile (Crocodylus niloticus) underwater holding a Great white pelican (Pelecanus onocrotalus) prey. after a group of the birds dove into the river to hunt fish. Here, the crocodile slowly sw...

Jen Guyton / Nile crocodile (Crocodylus niloticus) with Great white pelican (Pelecanus onocrotalus) prey. Other pelicans flying or wings held up in alarm. Msicadzi River, Gorongosa National Park, Mozambique. Duri...

Jen Guyton / Nile crocodile (Crocodylus niloticus) with Great white pelican (Pelecanus onocrotalus) prey. Other pelicans with wings held up in alarm. Msicadzi River, Gorongosa National Park, Mozambique. During th...

Jen Guyton / Yellow-billed stork (Mycteria ibis) fishing in the Msicadzi River, Gorongosa National Park, Mozambique, while a Nile crocodile (Crocodylus niloticus) swims past. During the dry season many water sour...

Jen Guyton / Nile crocodile (Crocodylus niloticus) emerging from the Msicadzi River, to swallow a mouthful of fish as a yellow-billed stork (Mycteria ibis) scans for fish nearby. Msicadzi River, Gorongosa Nation...

Jen Guyton / Marabou stork (Leptoptilos crumenifer) watching Nile crocodile (Crocodylus niloticus) that has come up to swallow a mouthful of fish. Msicadzi River, Gorongosa National Park, Mozambique. The bird is...

Jen Guyton / Nile crocodile (Crocodylus niloticus) surfacing to eat tiny fish whilst a Marabou stork (Leptoptilos crumenifer) looks on, ready to steal a fish if the opportunity arose. Msicadzi River, Gorongosa Nat...

Jen Guyton / Nile crocodile (Crocodylus niloticus) surfacing to eat tiny fish whilst a Marabou stork (Leptoptilos crumenifer) looks on, ready to steal a fish if the opportunity arose. Msicadzi River, Gorongosa Nat...

Jen Guyton / Nile crocodile (Crocodylus niloticus) surfacing to eat tiny fish whilst a Marabou stork (Leptoptilos crumenifer) looks on, ready to steal a fish if the opportunity arose. Msicadzi River, Gorongosa Nat...

Jen Guyton / Yellow-billed stork (Mycteria ibis) hunting for fish near a Nile crocodile (Crocodylus niloticus) that has come up to swallow a mouthful of fish. Msicadzi River, Gorongosa National Park, Mozambique. D...

Jen Guyton / Nile crocodile (Crocodylus niloticus) surfacing to eat tiny fish whilst a Marabou stork (Leptoptilos crumenifer) looks on, ready to steal a fish if the opportunity arose. Msicadzi River, Gorongosa Nat...

Jen Guyton / A Nile crocodile (Crocodylus niloticus) feeding on great white pelican (Pelecanus onocrotalus) in the Msicadzi River, Gorongosa National Park, Mozambique. During the dry season many water sources dry...

Ann & Steve Toon / Juvenile Nile monitor (Varanus niloticus), resting on tree trunk, Chobe River, Chobe National Park, Botswana, Africa, September.

Ann & Steve Toon / Nile crocodile (Crocodylus niloticus) feeding on Cape buffalo carcass, Chobe River, Botswana, September.

Jen Guyton / Marabou stork (Leptoptilos crumenifer) snatching a small fish from the jaws of a Nile crocodile (Crocodilus niloticus) that has come up to swallow the fish. Gorongosa National Park, Mozambique

Jen Guyton / Nile crocodile (Crocodylus niloticus) emerging from the Msicadzi River as Marabou storks (Leptoptilos crumenifer) look, Gorongosa National Park, Mozambique

Jen Guyton / Nile crocodile (Crocodylus niloticus) with Great white pelican (Pelecanus onocrotalus) prey, in the Msicadzi River, Gorongosa National Park, Mozambique.