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SWAHILI NAME: Mamba
PHYSICAL CHARACTERISTICS:
Nile Crocodiles' brains and hearts are more advanced than those of any other living reptiles. They have changed little in 65 million years. In contrast lizards, they have a "high walk." They swim with their tails, but their hind feet are webbed and can be used to submerge quickly. Adult Nile Crocodiles weighing 2,200 pounds and 21 feet long have been recorded

BEHAVIOR:
Crocodiles are not solitary predators as often imagined, but social creatures. Cows of some species protect not only their hatchling young but offspring from the previous year. Nile Crocodile bulls also respond to distress calls of their young., crocodiles convey social messages with motions, odors, postures, by touch and with sounds. Nile Crocodiles produce at least six different vocal signals. Both cow and bull Nile Crocodiles maintain territories, especially during breeding season.

DISTRIBUTION AND HABITAT:
Nile Crocodiles were once widely distributed over Africa south of the Sahara and on offshore islands. Their present range is smaller and they have become endangered because of habitat destruction and the value of their leather. They occupy a wide variety of freshwater habitats. Occasionally they are found on ocean beaches or river mouths.

REPRODUCTION and GROWTH
Bull crocodiles defend their territories during breeding season by roaring and constantly patrolling the borders. After mating which occurs in the water, the female digs a hole in soft soil, lays about 50 eggs and covers them with soil. Then she stands guard for three months, not even leaving to eat, while the eggs develop in the underground nest. 

The hatchlings call to their mother from inside their eggs when they are ready to hatch. the cow excavates the nest, carried the foot-long babies in her huge jaws to the safety of water, and continues to guard them for another six months. A group of baby crocodiles in called a crche.

Eggs and hatchlings are subject to predation by baboons, marabou storks and monitors by day, and by hone badgers, white tailed mongooses and other predators at night.

They have a lifespan of 70 to 100 years.

DIET:
Their diet varies with age. The juveniles eat spiders, frogs, insects, snakes, lizards and other small vertebrates. Fish make up a substantial part of the diets of older offspring and adults. Larger, mature Nile crocodiles capture zebras, antelope, wart hogs, large domestic animals and human beings. Crocodiles grab the large mammals at the edge of the water, drag them underwater and drown them