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Daryl

Definitely it is a Saltwater, or Estuarine Crocodile.

The Freshwater, or Johnson's Crocodile is a much smaller crocodile and also generally not dangerous, unless you step on one or something. I have swam in a lot of rivers, billabongs, lakes, waded out when fishing etc with Johnson's Crocodiles.

Fresh water is no reason to believe a saltwater crocodile will not be lurking or resident. They can travel a long way up into river systems and about the only deterent is steeper rocky terrain, eg waterfalls etc. Distance from the sea can be a factor, but Katherine in far inland in the NT, yet there were two saltwater crocodiles resident right in the middle of the town in the Katherine River. The Wet also allows crocodiles to spread much further.

I am not an expert so anyone can contradict me if they wish!

From a website on the Saltwater croc:

Geographic Range

Crocodylus porosus is most commonly found on the coasts of northern Australia, and the islands of New Guinea and Indonesia. It ranges west as far as the shores of Sri Lanka and eastern India, all along the shorelines and rivermouths of southeast Asia to central Vietnam, around Borneo and into the Philippines, and even out to Palau, Vanuatu, and the Solomon Islands. Saltwater Crocodiles are strong swimmers and can be found very far from land.

(Britton, 1995; Lanworn, 1972; Carr, 1972)

Biogeographic Regions:
oriental (native ); australian (native ); indian ocean (native ); pacific ocean (native ).

Habitat

The Saltwater Crocodile shows a high tolerance for salinity, being found mostly in coastal waters or around rivers. It may also be found in freshwater rivers, billabongs and swamps.

Movement between habitats occurs during the wet season, when juveniles are raised in freshwater rivers. However, these juveniles are usually forced out of these areas, by dominant males who use the freshwater areas for breeding grounds, and into areas of low salinity. Males who are unable to establish a territory in the river system are either killed or forced out into the sea where they move around the coast in search of another river system.

(Britton, 1995; Pope, 1955)

Terrestrial Biomes:
savanna or grassland .

Aquatic Biomes:
rivers and streams; coastal

Physical Description
Mass
1000 to 1200 kg
(2200 to 2640 lbs)

Saltwater crocodiles are the largest reptilian species alive today. Adult males can reach up to sizes of 6 to 7 meters. Females are much smaller and do not generally exceed 3 meters, with 2.5 meters considered large. The head is very large and a pair of ridges run from the eyes along the center of the snout. The scales are oval in shape and the scutes are small compared to other species. Young saltwater crocodiles are pale yellow in color with black stripes and spots on the body and tail. This coloration lasts for several years until the crocodile matures into an adult. The color as an adult is much darker, with lighter tan or gray areas. The ventral surface is white or yellow in color. Stripes are present on the lower sides of the body but do not extend onto the belly. The tail is gray with dark bands. Saltwater crocodiles have a heavy set jaw which contains up to 68, and no less than 64, teeth. (Britton, 1995; Kondo, 1970; Lanworn, 1972)

Some key physical features:
ectothermic ; heterothermic ; bilateral symmetry .

Sexual dimorphism: male larger.

Behavior

The Saltwater Crocodile has been thought of as one of the most intelligent and sophisticated of all reptiles. Their barks are a way of communicating with one another. The Saltwater Crocodile is thought to have four different calls. One is the distress call, which is normally only performed by juveniles. This call is higher pitched than most other calls and consists of short barks. They are also thought to have threat calls in which C. porosus makes a hissing or coughing sound at its intruder. There is also the hatching call. This call is only performed by newborns and is only one, short bark, high in tone. There is also the courtship bellow, which is a long, low growl.

The Saltwater Crocodile spends most of its time thermogulating to maintain its body temperature. If they become too hot they often go into the water with only their eyes and nostrils showing and stay submerged until they are cooled. If they become to cold, they lay in the sun on flat rocks until they warm up.

(Britton, 1995)

Key behaviors:
motile .

Food Habits

The Saltwater Crocodile is a predator and has many different types of prey. When young, Crocodylus porosus is restricted to smaller prey like insects, amphibians, crustaceans and small fish and reptiles. When they become an adult, they feed on larger prey such as mud crabs, turtles, snakes, birds, buffalo, wild boar, and monkeys. When the Saltwater Crocodile hunts for food, it usually hides in the water with only the nostrils, eyes, and part of the back exposed. When the prey approaches, it lunges out of the water and attacks, usually killing its prey with a single snap of the jaws. The Saltwater Crocodile then drags the prey under the water where it is more easily consumed.

(Britton, 1995)

Reproduction

The Saltwater Crocodile breeds during the wet season which falls between the months of November and March. Despite the fact that the Saltwater Crocodile is normally found in saltwater areas, breeding grounds are established in fresh water. Males mark out

their territory and become defensive if another male tries to enter. Females reach sexual maturity at around 10 to 12 years old. Males, on the other hand, do not reach sexual maturity until the age of 16 years. The female crocodile normally lays 40 to 60 eggs, but she can lay up to 90 eggs. The eggs are placed in mounded nests made from plant matter and mud and then buried. Since the eggs are laid during the wet season, the nests must be elevated to prevent loss due to floods.

The male does not stay until the eggs are hatched, but the female stays and protects the nest from predators and humans. After incubation for 90 days, the offspring are hatched, although this time varies with nest temperature. Sex determination is directly related to nest temperature. Males are produced around 31.6 degrees Celsius. If this temperature in increased or decreased just a little, females will be produced. The female unearths the eggs when she hears the chirping sounds the offspring make after they hatch. She then assists the offspring into the water by carrying them in her mouth and tends to them until they learn how to swim.

(Britton,1995)

Key reproductive features:
gonochoric/gonochoristic/dioecious (sexes separate).

Economic Importance for Humans: Negative

The Saltwater Crocodile can be a very dangerous animal to encounter, and humans are attacked and killed by this species every year. Many of these attacks could be prevented by increased awareness and education.

(Britton, 1995)
Economic Importance for Humans: Positive

The hide of the Saltwater crocodile is considered very valuable. Many people will pay large amounts of money to have crocodilian products, and Saltwater Crocodile leather products are the most prized. Farms are run for this specific purpose. The crocodile is raised until it is ready to be skinned for leather products. This is a contrversial topic as many people do not find it fit to kill the crocodiles to obtain a small amount of the hide, while the rest of the crocodile is thrown aside.

(Lanworn, 1972)

Conservation Status

IUCN Red List: [link]:
No special status.

US Federal List: [link]:
No special status.

CITES: [link]:
Appendix I.

Although the population of saltwater crocodiles is not stable everywhere, it is in no immediate danger. However, in some countries where the crocodile once thrived, it is now rare or extirpated. Habitat loss associated with coastal development and intensive hunting for hides has drastically reduced populations throughout much of the range. In Sri Lanka and Thailand, habitat destruction is so rapid that the saltwater crocodile has been virtually unseen, with only two saltwater crocodiles being sighted in 1999. In southern Vietnam, where the species once thrived by the thousands, there are but an estimated 100 crocodiles alive in the wild. This is due to the rapid degradation of habitat and the poaching of the animal for leather products. The global population will not be stable until all the countries which have habitats that support the saltwater crocodile have laws that prevent poaching, and programs that create reserves.

A number of such programs have been begun to ensure that C. porosus will not become extinct. In India, a restocking program was introduced in Bhitarkinaka National Park. More than 1,400 saltwater crocodiles were released, with approximately 580 surviving. The population has now become moderately stable at around 1,000 total crocodiles in India. In Burma, crocodile farms are controlling the breeding and conservation of

crocodiles. The Australian management program is the world's leader in conservation of the saltwater crocodile. This progam focuses its attention on educating the public on precautions to take if they encounter a crocodile, thus discourage unnecessary killing. Crocodile farms were opened to maintain a breeding population, and national sanctuaries have been established, ensuring an undisturbed habitat. Yearly population

counts are conducted, monitoring the number of saltwater crocodiles in Australia, making sure that the population does not become dangerously low. In New Papua Guinea, programs that ensure an undisturbed habitat stabilize the population. The Papua New Guinean management system involves a combination of wild cropping, egg and hatchling harvest, and ranching. (Britton, 1995; Carr, 1972)

Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Crocodilia
Family: Crocodylidae
Subfamily: Crocodylinae
Genus: Crocodylus
Species: Crocodylus porosus
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John aka NitroX

...
Govt get out of our lives NOW!
"I love the smell of cordite in the morning."
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