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Crocodile

 
 

Image: wikipedia.org (public domain)

Description: The Saltwater Crocodile is the largest of all living reptiles. Adults can grow to a staggering 20 feet in length and weigh over 2,000 pounds, though the average adult is about 17 feet long and weighs 1,000 pounds! Females are a little more than half as large as males. Adults are grayish, greenish, or brown in coloration with lighter underparts. Their heads are extremely large and the jaws are very powerful. Saltwater Crocodiles have 64-68 sharp teeth. Younger crocodiles are yellowish with black stripes. Compared to other species of crocodiles, the Saltwater Crocodile has fewer armor plates on the neck and is much thicker. This species of crocodile is thought to be fairly intelligent. Research has shown that they have at least four different communication calls, one that indicates distress, a call that indicates the presence of a threat, one for courtship, and another made by hatchlings. Researchers have also found that the Saltwater Crocodile has learned to track the migratory patterns of their prey as climate changes. This species is a powerful swimmer, capable of traveling at 15 miles per hour, though it normally travels at only two or three miles per hour.

Diet: The Saltwater Crocodile will eat anything that it can catch. Although attacks on humans are rare, this species is considered one of the most dangerous in the world, as there are many documented cases of humans being killed or injured. The Saltwater Crocodile is an apex predator (at the top of the food chain) and normally kills water buffalo, monkeys, boars, kangaroos, birds, large fish, and anything else that is available. This species hunts by ambush and strikes at prey without warning, using its great strength to drown its victim in the water or by crushing its head with its jaws. In a “death roll,” the crocodile will latch onto an animal and roll its body violently, causing the victim to lose balance and fall into the water.

Habitat/Range: The Saltwater Crocodile actual spends much of its time in freshwater swamps and rivers, moving downstream to bays and estuaries during the dry season. They are sometimes found far at sea. The Saltwater Crocodile ranges throughout much of southeast Asia, from eastern India, east through Indonesia and the Philippine Islands, to the northeast coast of Australia. It is most numerous in Australia and New Guinea and becoming less numerous in southeast Asia.

Nesting: Male crocodiles compete fiercely with one another for the rights to mate with females. Those males that are unsuccessful in defending their territories are often killed by other males. Females reach reproductive age at between 10-12 and males at age 16. After mating, the female lays between 40-60 eggs in a nest of vegetation positioned away from areas they could flood. Eggs hatch in approximately 90 days. Gender of the young crocodiles is determined by temperature. Male crocodiles are born if incubation temperature is near 31.6 degrees, otherwise, female crocodiles are born. Mother crocodiles bring hatchlings to the water in their mouths.

Status: Saltwater Crocodiles are declining in much of their range, most dramatically in southeast Asia. Nevertheless, it is not thought of as a threatened species.