Salt Water Crocodiles

Crocodylus porosus

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  1. Saltwater Crocodiles vs. Freshwater Crocodiles
Freshwater crocodiles have a noticeably narrower snout, and they are smaller in size. Freshwater crocodiles generally only in fresh or lightly salty water, they lay their eggs in sand, and reproduce in dry season. Saltwater crocodiles on the other hand can live in either fresh or salt water. They are much larger in size, lay their eggs in vegetation and reproduce in the wet season which is November to March.
Saltwater Crocodile
Saltwater Crocodile
Freshwater Crocodile
Freshwater Crocodile

2. Characteristics
Saltwater Crocodiles are the Earth's largest living crocodilian and reptile. Male crocodiles can grow up to 22 ft, while females are usually smaller and grow up to about 13 feet. They have a large head with extremely powerful jaws, around 60 to 70 teeth.Young saltwater crocodiles are a yellowish color with black stripes on their body and tail, while adults are a darker color with occasional spots. Saltwater crocs, or "salties," as Australians affectionately refer to them, have an enormous range, populating the salty and freshwater regions of eastern India, Southeast Asia, and northern Australia. They are excellent swimmers and have often been spotted far out at sea. Their rrear feet are webbed for swimming, which is why they are sometimes spotted far out at sea. The tail of the estuarine crocodile is 49.5% of its total body length, the longest of any crocodile. The tail is used to propel the animal through the water and scutes (spikes) along the top of the tail are an important part of the tail. Not only do they increase the surface area and therefore thrust for the tail, they are made of cartilage, have a good blood supply and are an important device used for temperature regulation.

3. Habitat
Saltwater crocodiles originate from Northern Australia, and as mentioned before have been known to travel to eastern India, Southest Asia, and northern Australia.
An extremely interesting characteristic of Saltwater Crocodiles is their Thermoregulating Behaviour. Often you will see a saltwater crocodile gaping (its mouth open). This enables the Croc to cool down, as a lot of their time is spent thermoregulating as Crocs are cold blooded (their blood temperature is effected by the weather around them). With a preferred body temperature of 30° to 33° C, crocodiles use the water, sun and shade to regulate their body temperature and move between these warm and cool parts of their environment to adjust it. In regards to the mouth gaping posture, one theory is that this is done to cool the brain through evaporation from the palate while the body is heated by the air and sun. Furthermore, Saltwater crocodiles are unique in the reptile world and use their blood system to remove salt from the body. Lingual glands at the back part of their fleshy tongue excrete excess salt when the animal is living in a highly saline environment.

4. Eating Behavior
Saltwater crocodiles are carnivores.Young crocs will eat small mammals, insects, shellfish, and fish. Adults will eat snakes, buffalo, cattle, board and even sharks. They lunge at prey, often killing it with their jaw. The crocodiles will drag underwater to drown the prey and consume it, and have been known to eat people.

5. Social Structure
Saltwater crocodiles live in loosely organized social groups and are extremely territorial. The best territory is held by the strongest male, kept through posture and vocalizations, not usually through violence.

6. Birth & Offspring
Mother crocodile lurking below the water to protect her eggs.
Mother crocodile lurking below the water to protect her eggs.

Saltwater crocodiles surprisingly usually breed in freshwater. As already mentioned nesting takes place in the wet season after males fight for the females. The female croc builds a nesting mound of vegetation, mud and soil (about 2 meters long) and lays between 40 and 60 leathery eggs inside the mound. This mound raises the eggs above the water level hopefully saving them from damage. She then guards the nest for 3 months until the young hatch. The young crocs then use a special egg tooth on the top of their snout break free from their eggs. Carefully carrying her young in her mouth, the female crocodile takes them to the water. A really interesting fact I discovered when doing my presentation is that incubation temperature determines the gender of the hatchlings. Very high or low temperatures producing females, and 31 degrees to 32 degrees celcius producing males. Pigs and other animals eat crocodile eggs which contributes to only 25% of eggs laid will hatch. From those hatchlings, less than 1% survive to adulthood.

7. Threats
As previously mentioned, young crocodiles are in danger from other crocodiles and predators. Saltwater crocodiles are extremely dangerous resulting in several attacks to humans annually, sometimes resulting in death. Also, Saltwater crocodile leather is in high demand, and crocodile farms are establish to raise crocodiles solely for their hides. Like other animal skin and fur trades, this practice is highly controversial among those concerned with animal welfare. Saltwater crocodiles are not yet officially threatened, however in many countries populations have declined significantly due to illegal hunting, habitat loss, and apathy towards the species because its reputation as a man eater.

8. In the Media
Phillipine villagers with a live Saltwater Crocodile.
Phillipine villagers with a live Saltwater Crocodile.

On September 4, 2011, a town in the Phillipines captured a one-ton saltwater crocodile. It could be one of the biggest crocodiles to be captured alive in recent years.The crocodile was witnessed by villagers last month killing a water buffalo,and is also suspect of killing a fisherman in July. The town used steel cables to capture the enormous crocodile and 100 people were needed to pull the 2,370 pound animal from the creek to a crane. It was placed in a caged area in the town where it is to be the star of an ecotourism park .

Brutus: Saltwater Crocodile
Brutus: Saltwater Crocodile

In July 2011, a tourist in Northern Australia snapped this photo of a saltwater crocodile. Brutus, as he is commonly called, measures in at around 18 feet long, and weighs in around two tons. It puts into perspective the enormous size and power of the saltwater crocodile and it’s popularity

By: Regina Loftus '12


1. National Geographic: Animals Gone Wild: Salt Water Crocodile. 2011. National Geographic Society. September 2011.

2. Marine Bio: Saltwater Crocodiles. 2011. Marine Bio Conservation Society. September 2011.

3. The Big Zoo: Saltwater Crocodiles. 2008. theBIGzoo. September 2011

4. Yahoo News: Giant Crocodile Captured Alive in Phillipines. 2011. The Associated Press. September 2011

5. Unique Australian Animals: Saltwater or Estuarine. 2000. K. Gazecki. September 2011

6. Eco-Tourism Australia: About Saltwater Crocodiles. 1998. Crocodile Safari. September 2011

7. Saltwater Crocodile. 2008. Australian Infauna. September 2011