Friday, July 2, 2010

Salty vs' Fresh

Prior to visiting the Top End of northern Australia I didn't know a whole lot about crocodiles, except that the Land Down Under has some fierce ones--or at least that was the picture that had been painted in my mind.  So as we sped past the first Crocodile Safety sign at the side of the road in Litchfield National Park, I quickly pulled out the guide book to learn more about the reptile whose habitat I was about to enter.  It turns out that there are more than 20 types of crocodilians in the world, and two species are found in Australia: the freshwater and the estuarine or saltwater crocodile.

Freshwater crocodiles are only found in Australia.  "Freshies" live in freshwater rivers, creeks and plunge pools.  They are relatively small and rarely grow to more than 2.5 meters in length and weigh no more than 60 kilos.  The nocturnal predator, enjoys a diet of birds, bats, reptiles, insects, fish, and small mammals. They are considered to be a timid animal, though they can become aggressive and bite if they are disturbed.  Fortunately, their jaws are not large or powerful enough to cause serious injury to humans.
Estuarine crocodiles are found in Australia, South East Asia, New Guinea and Indonesia.  Saltwater crocodiles live in estuaries and the sea, but during the wet season they can move into freshwater swamps and rivers .  "Salties" are the world's largest living reptile and the males average a length of five meters and weigh about 450 kilos.   Their diets are similar to their freshwater cousins, however they may also eat snakes, turtles, and larger mammals (including water buffalos and humans).  It is important to note that less than 30 people have been killed by crocodiles since 1971, but they are still an opportunistic predator that will quickly strike without warning.

Today there is an estimated population of 100,00 crocodiles in Australia.  However, from the 1940's thru the 1960's the reptile was hunted, for its skin, to near extinction.  They are now a protected species and it is illegal to injure or harm them.
As the estuarine crocodile population grows, they continue to move further inland into freshwater rivers, billabongs and creeks in search of new territory.  Thus, the National Parks of the Top End have had to implement crocodile management zones.  These zones are only open during the dry season, and are accessible after the areas have been extensively surveyed and any "salties" that have moved in during the wet season have been removed.  Traps remain in place for the entire dry season as a saltwater crocodile may move in at any time.  So when visiting the Parks of the Northern Territory it it critical that all warnings and closures be followed.

1 comment:

  1. Hi Maya, this is interesting. I had no idea that there were two types of crocs. The Salties sounds scary so I'm glad to read that the parks closely manages the area. Seems to work since there has been no deaths since 1971. Take care.