Crocodiles and False Gharials: Crocodylidae

Physical characteristics: A large and bulky-bodied species, the Nile crocodile has a very lumpy, dark brown to gray back and a light yellow, white, or gray belly. Youngsters are greenish brown to brown with dark markings. Females usually reach about 8 feet (2.5 meters) long, and males typically grow to about 11.5 feet (3.5 meters).

Geographic range: Nile crocodiles live in Africa south of the Sahara Desert and on Madasgascar off Africa's southeast coast.

Habitat: Nile crocodiles mainly live in freshwater habitats, including marshes, lakes, and rivers.

Nile crocodiles spend much of their time in the water, either stalking prey or lying in wait for an animal to come close enough to attack. (©Charles V. Angelo/The National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission.)

Diet: The adult diet is mostly fish, although Nile crocodiles will also eat large mammals, such as warthogs and antelopes.

Behavior and reproduction: Nile crocodiles spend much of their time in the water, either stalking prey or lying in wait for an animal to come close enough to attack. With their powerful jaws, they can clamp onto even large animals and drag them underwater. After the animal drowns, the crocodile may twirl the animal in the water in an attempt to tear off a chunk of flesh to eat. Nile crocodiles often live in large groups and often bask together on the shoreline. During the August-to-January mating season, however, males will fight one another. After a male and female mate, the female goes off to dig a hole high on shore and lay her 50 to 80 eggs inside. The mother remains nearby, and 80 to 90 days later, she helps her now-hatched young out of the nest and to the water. The young stay under their mother's watchful eye for another month or so, and then go off on their own.

Nile crocodiles and people: These animals occasionally attack and kill ranchers' cattle and other livestock, and very rarely, a person. Some people hunt this reptile for its meat and skin.

Conservation status: Although it was once overhunted, the World Conservation Union (IUCN) no longer considers this species to be at risk. The U.S. Fish and Wildlife Service, however, lists it as Threatened, or likely to become endangered in the foreseeable future. Numerous guidelines are in place to help make sure the crocodile survives into the future. ∎