Appearance

The saltwater crocodile is the largest reptile currently alive today reaching lengths of up to 7m and potentially weighing over 1 tonne. Males are much larger than females when fully grown with females typically only reaching 4m. Some unconfirmed reports exist of saltwater crocodiles which were between 8 and 10 metres long.

Crocodiles are well built for life in the water. Their hind feet are webbed, and their strong tail helps to propel them through the water. Their eyes have a nictitating membrane which acts as a clear covering for the eye when they dive under the water. Their ears are also covered by a flap to keep out water when they are fully submerged. Further to this a waterproof flap keeps water out of the windpipe when they are attacking prey under the water.

The shape of their head allows them to be almost fully submerged while still having the ability to see, smell and hear. The eyes, nostrils and ears sit on a ridge on top of their head which allows them to keep these out of the water while swimming.

Their back colour varies between olive, grey and yellowish with some black patterning. The underside is white. Juveniles have more black stripes and spots which fade as they age.

Lifespan

Saltwater crocodiles have an average lifespan of 65 to 70 years though some are believed to have lived to over 100 years old.

Diet

The saltwater crocodile is a carnivore. They feed on a wide range of prey covering birds, mammals, reptiles, crustaceans and fish. Juveniles will also feed upon insects and amphibians. It is possible for an adult crocodile to take down a water buffalo, kangaroo or shark. In some cases, they have been recorded eating the smaller freshwater crocodile.

To aid digestion the saltwater crocodile can digest stones to help grind up their food.

Saltwater crocodiles are one of the few species in Australia which will attack humans in Australia. In Northern Australia it is important to be vigilant and follow warnings posted at beaches and rivers.

Their ability to sit with their eyes and nostrils out of the water with the rest of their body submerged allows them to sneak up on prey at the water’s edge before quickly emerging out and grabbing prey before dragging it back in to the water for their death rolls which serve to drown the prey.

Habitat

Saltwater crocodiles are found in the North of Australia across Queensland, the Northern Territory and Western Australia. They also occur throughout Asia ranging across to India. They can travel up to 1000km through the ocean.

Unlike their name suggests the saltwater crocodile is not just found in saltwater also being found in brackish and freshwater. They can be found around the coast in mangroves along with in inland rivers, billabongs and marshes.