About Crocodile

7/29/2019 About Crocodile

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I think that crocodiles are quitefascinating animals and the more thatpeople know about them, the better

they can understand them. Hopefullyby understanding them, people maydevelop an appreciation of crocodileswhich in turn may lead to some rationaldecisions being made about their long-term conservation and managementhere in Australia.



Crocodilians are the worlds largest andperhaps most exciting reptiles. They are also

great survivors and their prehistoricancestors, the Archosaurs, date back over 240million years to the Triassic period. They

have survived major upheavals such as thebreak up of the continents and the ice ages.They have witnessed the rise and fall of thedinosaurs and have seen the evolution ofmammals and birds. Since man colonised theworld, no species of crocodile has becomeextinct; however 17 out of the 23 species ofcrocodilians around the world areendangered.



They have distinctive features such as long jaws, protective armour, streamlined body

and long tail. These, together with variousanatomical and physiological adaptations,make the crocodile perfectly suited to anaquatic and predatory lifestyle. Their featureshave changed very little from those of theirprehistoric ancestors, proving that their bodyform has been highly successful in nature.

Some experts believe that the crocodile, in itspresent form, has not changed for the last 100million years. Maybe a perfect design?



Crocodiles are cold blooded and have a body

temperature similar to the surrounding air, landor water. Since they lack a reptilian thermostat,they seek a habitat with warm water and airtemperature all year round. Though muchmaligned, crocodiles play an important role in

wetland environments. They help keep thebalance in the complex web of life in freshwaterand estuarine ecosystems. They are key predatorsat the top of the food chain and eat a wide rangeof prey. They are also prey, when smaller, to

other animals such as feral pigs, goannas, turtles,barramundi, sea eagles and even other crocodiles.Being predator and prey, the crocodile plays animportant role in keeping a wetland ecosystemhealthy and when a wetland habitat is healthy,

the fishery is considered to be healthy too.



The Freshwater crocodile (Crocodylus

johnstoni) is endemic to Australia. It is foundnowhere else in the world. "Freshies" occur onlyin inland waters of Northern Australia, and inQueensland; they are found mainly in the riversand swamps of Cape York Peninsula, areas

bordering the Gulf of Carpentaria and thenorthwest. They also live in the tidal reaches ofsome rivers and therefore co-exist at times withestuarine crocodiles. They have a narrow snoutand reasonably straight jaw line with even sized

teeth. Males can grow to 3 metres but animalslarger than 2.5 metres are rare. Females rarelyexceed 2.5 metres. They are not "man-eaters" andfeed mainly on insects, frogs, lizards, turtles,with bats, birds and small mammals being taken

occasionally at the water's edge. Even larger"freshies" tend to eat very small food items.



The Estuarine (Saltwater)

crocodile (Crocodylus porosus) isfound in the warm climate fromSri Lanka and India in the west tothe Caroline Islands in the east, to

the north from Burma and South-East Asia, to Australia, Vanuatuand the Solomon Islands in thesouth. In Australia, they arerestricted to northern parts of the

continent, from aboutRockhampton on the east coast ofQueensland to Broome on thewest coast of Western Australia.



Young crocodiles are bornwith a horn or egg tooth onthe tip of their snout, whichlater drops off. This enablesthem to break out of the egg.

When hatching, young

crocodiles squawk to attractthe mother, who may in turndig them out and carry themgently to the water in her

mouth. Unhatched eggs aresometimes rolled around onthe mother's tongue to helpthe young emerge.

About Crocodile

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