(a) Crocodilia: crocodiles, alligators, caimans & gavials
(b) Testudines: turtles, tortoises & terrapins
(c) Rhynchocephalia: tuatara (New Zealand)
(d) Squamata: lizards & snakes (the modern reptiles)
1. Australian freshwater crocodile grows to 3 metres. The saltwater croc was believed to reach 9 metres in the old days, however it is now known to grow to about 7 metres (rare over 5).
2. Freshwater 25 centimetres, saltwater 25-30 cm.
3. Anything small enough to swallow! The freshwater croc has been recorded eating small fish, frogs, crayfish, shrimp, insects, spiders, lizards, smaller crocs and small mammals. The salty eats the same as the freshy but also birds, snakes, turtles, turtles' eggs, larger mammals like wallabies, and sometimes decaying animals including other crocs.
4. Of the world's 20 odd species, the freshwater croc is amongst the smallest.
5. The saltwater or estuarine croc.
6. About 20-25 kph over very short distances.
7. Freshy 10-25 eggs, salty 40-80 eggs.
9. Both Australian species occur from the Kimberley in WA around the coast to about Townsville, Queensland for the freshy and as far south as Maryborough, Queensland for the salty.
Crocodiles are believed to occur today as they did almost 150 million years ago. They have definitely survived since the dinosaur's days. In Australia both species have been extensively hunted for their skins in previous years and it was feared they would become extinct. They are now protected but, because the salty is large enough to take humans and their numbers are increasing, there are moves to allow controlled culling especially in areas close to towns and human recreation spots. I believe this is the sensible way to go because if the wildlife authorities are not seen to be managing the population in a way that both benefits the crocs and people, you will find that idiots will go off killing them indiscriminately.
Baby freshwater crocodiles hatch after about 3 months incubating at the beginning of summer before the monsoon rains (wet season) arrive. They leave the nest and scramble to the water where the mother awaits them. She will remain with them for awhile giving protection. The babies first meals are insects. The babies are in turn preyed on by pythons, monitor lizards and large hunting birds such as sea eagles. If they survive the predators they may live for more than 30 years.
Baby saltwater crocodiles incubate in the eggs for about 3 months also. When hatching they call to their mother. She may assist her babies out of the nest and may occasionally carry them one at a time to the water. The same predators are out to get them as the freshy. However, if they survive to adulthood the only predator they have to worry about is man (and woman). They are believed to live for upwards of 100 years.