Facts of Crocodiles

        The Crocodylus acutus (American crocodile) is a large, greenish-gray crocodilian with black mottling. In Florida, adults reach lengths of about 12 ft (3.8 m) although a specimen measuring 15 ft (4.7 m) was reported in the late 1800s. In other portions of their range, individual crocodiles may reach 20 ft (6.0 m). Like all other crocodilians, males are larger than females. All adults have a hump above the eyes which may or may not be distinct, and irregular, asymmetrical dorsal armoring. Hatchlings measure approximately 10 in (27 cm) and are normally yellowish tan to gray with dark cross markings on the body and tail. These markings fade as the animal grows. A lateral indentation of the upper jaw leaves the fourth tooth of the lower jaw exposed when the mouth is closed. Compared to the alligator, the American crocodile may be distinguished by its longer, narrower, more tapered snout and the exposed fourth tooth of the lower jaw.



Nile crocodiles are the largest African crocodilian, reaching lengths of up to 5 m (16 ft), or rarely up to 5.5 m (20 ft). Good sized males weigh 500 kg (1100 lb), while the female are 30% smaller than males. They easily snatch and devour a human. They have four short, splayed legs; long, powerful tails; a scaly hide with rows of ossified scutes running down their back and tail; and mighty jaws. They have nictitating membranes to protect their eyes and, despite the myths, they do have lachrymal glands, and can cleanse their eyes with tears. Nostrils, eyes, and ears are situated on the tops of their head, so the rest of the body can remain concealed underwater. The underbelly is yellowish, and makes high-quality leather. They normally crawl along on their bellies, but they can also "high walk" with their trunks raised above the ground. They are capable of surprising bursts of speeds, briefly reaching up to 12 to 14 km/h (7.5 to 8.5 mi/h). They can swim equally fast by moving their body and tail in a sinouous fashion.


                   These reptiles are unusually attentive parents. It all begins when a large male croc spots a female that catches his eye. He bellows and splashes, slapping his snout on the water to get her attention. He grunts and growls, and sometimes, inhales as hard as he can, submerging his snout and blowing water through his nostrils, producing a fountainlike spray.  If the female is willing, the pair rubs the undersides of each other's jaws while sending out warbling sounds-the beginning of a courtship.  The female croc is ready to lay her eggs nearly two months after mating. She scouts the area for a suitable nest site in which to lay the eggs, usually digging a hole on a riverbank, shoreline, or dry streambed. She deposits from 25 to 80 eggs in the nest, then settles in for a long vigil. For a reptile, it's an unusual display of devotion. Other reptiles lay their eggs, then move on.  The female croc, however, will keep constant guard over the nest during the three-month incubation period, leaving only to cool off in a nearby shady spot or for a quick dip in the water. The male is usually close by to help scare off predators. Just before hatching, the young crocs send out high-pitched sounds-a signal for help.

The female digs up the nest. It's not unusual for both male and female parents to assist in the hatching by gently taking the eggs in their mouths and rolling them back and forth on their tongues, allowing the hatchlings to break free.  The mother croc then carefully picks up the 12-inch- (30.5-centimeter-) long hatchlings in her mouth and carries them to the water. 

The young crocs live under their mother's protection for up to two years, feeding on insects and small fish and growing about a foot (30.4 centimeters) each year.