One of the three species of crocodile found in Africa, the Nile crocodile is the second largest crocodile in the world and inhabits larger rivers, lakes, estuaries and swamps in sub-Saharan Africa, the Nile basin and Madagascar. The Nile crocodile is characterized by its four short, splayed legs, a flat, powerful tail, a scaly hide and a strong jaw. Adult males can reach up to 20 feet in length and weigh well over 1,000 pounds.
While it does come ashore to bask on hot days, the Nile crocodile is primarily designed to be hidden in the water. The placement of ears, eyes and nostrils on the top of the skull allow it to stay nearly submerged all day, and its olive coloring also aids in concealment.
The Nile crocodile feeds on fish, antelope, zebras and buffalos, leaping up to catch nesting birds or to pull large animals beneath the water. It also has a well-deserved reputation for killing humans, since its habitat is in close proximity to people.
Like other crocodilians, it can bite but cannot chew, which is awkward when hunting larger prey. As a solution, the Nile crocodile drags large prey underwater, using a twirling method, called a “death roll,” to tear off large chunks of flesh. The crocodile’s mouth is filled with 68 teeth and is capable of exerting impressive force while clamping onto prey.
Populations were bought nearly to extinction in the mid-20th century, as the Nile crocodile was hunted for leather and meat. National protections and international trade regulations have helped them rebound in many areas. The species is still threatened by illegal hunting, pollution and habitat loss. There are an estimated 250,000 to 500,000 species left in the wild.
Like other crocodilians, Nile crocodiles have temperature-dependent sex determination, which means the sex of their hatchlings is determined not by genetics, but by the average temperature during a portion of their incubation period. Offspring will be male only if the temperature inside the nest falls between the narrow range of 89.1 F and 94.1 F. Otherwise, offspring will be female.May 14, 2012