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Austalian freshwater crocodile

Johnston’s Crocodile

Crocodylus johnstoni

Austalian freshwater crocodile Austalian freshwater crocodile Austalian freshwater crocodile Austalian freshwater crocodile

Freshwater crocodiles have strong legs, clawed webbed feet and powerful tails. Equally fast on land and water, these crocodiles can move at speeds of up to 18 miles per hour.

This croc is gray or olive-brown with a lighter underside and darker mottling or bands on the upper body, tail and sometimes snout. It has a smooth, narrow, tapering snout and a mouth lined with 68 to 72 sharp teeth. The fourth tooth on either side of the bottom jaw protrudes outward and can be seen when the animal's mouth is closed.

In the dry season, females lay about 20 eggs in sandy hollows, which they protect until they hatch. Hatchlings call from within the egg before hatching. An adult female responds by excavating the nest, picking them up in her mouth and carrying them to the water.

Did You Know?

These crocs bask with their mouths open to prevent overheating.


In the wild, juveniles feed on insects, crustaceans and small fish. Larger crocodiles extend their diet to include amphibians, bats, large fish and land mammals. Adult crocodiles are sometimes cannibalistic and may eat juveniles. The Aquarium's crocodiles are fed fish, chicks and mice.


Johnston’s Crocodiles reach an average of 6 feet and 32 pounds, though some can grow upward of 9 feet and 48 pounds.


This species is restricted to the tropical regions of northern Australia (Queensland, Northern Territory and Western Australia) and is found mainly in freshwater lakes, rivers and wetlands.

Population Status

In the past, this species was at risk of extinction because crocodiles were hunted for their skin. The population has made a comeback due to protection and sustainable farming, and there are an estimated 100,000 individuals in the wild. Habitat destruction is still a major threat.


Adult crocodiles, black kites, whistling kites, turtles and large fish eat juveniles, and lizards prey upon nests. Some aboriginal people hunt these crocs for food.

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