The Freshwater crocodile (Crocodylus johnstoni or Crocodylus johnsoni) are only native to northern Australia. They are found in inland freshwater areas of the Australia including rivers, freshwater wetlands, creeks, lagoons, swamps, and billabongs.
Their range overlaps with the saltwater crocodile range, and they can be found in the same areas as the Freshwater crocodile is somewhat tolerant to saltwater.
They are also known by other common names like Johnson's Crocodile, Australian Freshwater Crocodile, Freshie, Johnston's Crocodile or Johnstone's Crocodile.
They are a relatively small crocodile species, and much smaller than the saltwater crocodile, they also have a much narrower snout. Male freshwater crocodiles can measure up to 3 meters in length, however females are much smaller, and rarely grow more than 2 meters long. Freshwater Crocodiles have a lifespan of 50 or more years, with most of their growth occurring in the first 20 years.
They are capable of moving at an incredible speed on land reaching up to 17 km/h, they do that by galloping and are one of the crocodiles to do so. This is probably a defense mechanism against predators like the saltwater crocodile.
They are a shy species, and aren't considered dangerous to humans, like their bigger relative the saltwater or estuarine crocodile. However they can deliver a very nasty, crocodile bite, if provoked or disturbed. Their body color is light brown with some darker bands on the body and tail.
Freshwater crocodile - Diet
Their diet consists of all kinds of smaller animals you can find near rivers. This includes insects, fish, frogs, turtles, waterbirds and snakes. The small mammals that come to drink at rivers are also sometimes taken. The larger adults will feed mainly on these smaller mammals including wallabies.
Freshwater crocodile - Reproduction
Males will only be sexually mature at about 15 years and females when they are about 12 years old. This species breeds during the dry season, in the months of July and August. Females will dig a hole in a sandy riverbank, and lay up to 12 eggs. The eggs will hatch in about 2 to 3 months.
The eggs are will be left unprotected so many nests are destroyed by predators like goannas or feral pigs to feed on the eggs. Indigenous people also eat the eggs as they are a favorite seasonal food.
The female returns to the nest in the end of the incubation period. They will help the hatching process, and show parental care for the offspring, during a variable period of time.
The hatching happens near the start of the wet season, to avoid flooding in the nest and when insects are particularly abundant as they will be the young main source of food.
Freshwater crocodile - Conservation status and major threats
They were, like other crocodile species, hunted for their valuable skins, specially after advances in tanning processes (1950's) and the saltwater crocodile population was reduced. The skins were used to make crocodile skin products like bags, hand bags and other expensive products.
Freshwater Crocodiles have been protected from hunting since 1960's and their numbers have grown, and are now estimated to be at around 100,000 individuals in the wild. The species is listed on CITES Appendix II and is considered by IUCN as a Lower Risk/least concern.
Although habitat destruction is still a threat, they inhabit mostly unpopulated or lightly populated areas. Nowadays the main current threat to Freshwater Crocodiles seems to be poisoning by the Cane Toad (Bufo marinus). Some crocodiles will eat the toad and are killed due to poisoning.
Facts about crocodiles for kids
Alligator facts for kids
Where crocodiles live
Where do alligators live
Did you know?
Alligators haven't changed that much in the last 180 million years.