Zoology

The Saltwater Crocodile in Australia



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The Saltwater Crocodile in Australia.

In 1971 the Saltwater or Estuarine Crocodile (Crocodylus Porosus) was given endangered species status in Australia. It joined Australia's native Freshwater Crocodile (Crocodylus Johnston) with this protection. The Saltwater Crocodile or Salty grows to about 20' in length can have a girth of 6' and can weigh up to a ton. It is a known man-eater and kills a couple of people a year. The Freshwater crocodile is much smaller and can provide a nasty bite but has never been known to kill anybody.

The Salty reached a dangerously low level in the 1960's as a result of 40/50 years of intense hunting to satisfy a market for Crocodile skins. It inhabits the North of Australia where hot damp conditions for much of the year provide it with a perfect habitat. It also provided a frontier style hunting culture that thrived and created many so-called characters that killed Crocs and/or Buffaloes, were hard drinkers and often had good reason to stay in the bush.

A carry over from those days can be found in the daily newspaper for the Northern Territory which two or three times a week has iconic Croc. stories on its front page. These are often presented in a manner, which evokes the odd laugh, and no doubt to the uninitiated could make the Salty appear as some form of benign visitor. Nothing could be further from the truth.

The Salty has the most awesome measure of violence related speed in the animal world. Its massive tiller style tail can propel it forward at such a rate that it can leap vertically up to 2/3rds of its body length. Imagine a ton of animal lunging up to 14' into the air from the placid depths of a river or creek. It is awesome violence when it is used to attack. It is very fast over the 2/5 yards when on land but like all cold-blooded creatures it lacks stamina and needs a fair amount of recuperation time.

The Crocodilus family have never had much need to adapt. They are the same now as they were when the dinosaurs were here. When you are perfect for your lifestyle there is no need for adaptation. We should not be surprised therefore that the recuperative powers to bounce back after nearly being annihilated has now evidenced. In the Northern Territory, which arguable has the best information of any jurisdiction, the population of Salty's has gone from about 2000 in 1971 to about 80,000 today. This despite having a number of management plans in place that sees the capture of about 200 specimens in Darwin Harbour annually, the rights of indigenous people to catch them as a food source and the harvesting of 25,000 eggs from the wild each year.

Anecdotally nothing is the same in the Territory creeks, waterholes and rivers as it was when the current generation were growing up. Places where swimming was low-risk is now outright dangerous and places that had never seen Crocs are now seeing them. The ever-persuasive sprawl of mankind into previous pristine habitat has increased the number of incidents unfortunately some with tragic results.

It is easy sometimes to consider a large black aqua reptilian as long on instinct and short on brain. Not so with the Salty whose capacity to stalk is legendary. They attack by ambush and will go to great lengths and show extraordinary patience to set the scene to their advantage. Our First Australians speak of the three day shadowing by large Crocs. "You can't see him but he can see you and Day one he will see where you go to sit, where you get your tea billy filled and where you go near the water. Day two he will check again to see you going, then on Day three, he attack and you no more". Saltys have big jaws and can exert pressure of 7 tons to the square inch with their closing. They have a very small stomach, not much bigger than a basketball, and consequently use a rolling method to aid with killing and dismembering prey.

To be Crocodile smart in the northern part of Australia is to respect the fact that they are the best that there is at what they do. They are descendants from the Triassic Age and have been here for about the last 240 million years. They are fascinating to see in the wild and to see and appreciate how marvellously equipped they are to handle their needs. They must not be underestimated in locale or intent. They are very dangerous.

In the rejuvenation of the species over the last 40 years they have been aided from a strange quarter. In 1935 the fledgling Australian Sugar Cane industry was under attack from the grey backed cane beetle and the frenchie beetle. In order to control these pests a predator was sought and cane toads were imported from South America. Within 6 months over 60,000 young toads (Bufo Marinus) had been released into the sugar cane areas of Queensland. They thrived in the Australian conditions and are now in plague proportions over the whole top end of Australia. They are toxic to other species and have decimated large numbers of native fauna.

Most important of these are the monitor lizards or goannas. These large lizards were credited with taking 90% of the Crocodiles egg clutches thus contributing to a very effective limitation on numbers. With that threat now reduced dramatically it is aiding this tremendous resurgence in the numbers. The question being asked of course is how much and what needs to be done to slow the rate of growth in numbers and ensure safety of the human population.

There is currently a proposal on the Minister of Conservation's desk to allow safari style hunting for 50 Salty's a year. Well that is going to do nothing but take out 50 aged specimens, it is going to do nothing to total numbers. We are awaiting a management plan that provides for a 35-mile boundary around Darwin, which will be kept Salty free. The danger of this plan is of course that it will be impossible to monitor completely and with accuracy and could lead to a lowering of awareness or an increase in risk taking and therefore be self-destructive.

Crocodile skins are big business and are being required worldwide. The harvest from the wild of 25,000 eggs ahs been mooted to double. It is important to note that harvesting eggs is a very dangerous business and to double the number will double the risk. It is done in an environment where the mother Croc has the advantage and if high vigilance falls then tragedy will occur. It is this sort of dilemma that faces many of our conservation challenges. The day the decisions are taken we are on a changing slope and outside influences could and do change our forecasted outcomes. We have to be ready for them.

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