Mother calls for croc cull after near miss

[Bluetongue1]

The relatinships between feral animals and crocs are not simpleand clear cut. Some of the genenral effects of ferals:
Pigs, buffalo, horses and cattle are all herbivores with hooves. Buffalo produce wallows, mostly in billabongs, which destroy gasses, sedges, waterlilies and reeds, which are important food sources for other animals. They also muddy the water and increase salt intrusion. Pigs dig up the ground around springs and rainforest patches, esp0ecially in the wet, leaving the soil exposed soil vulnerable to erosion and weed establishment. In fact pigs are believed to be the major factor in spreading the noxious weed mimosa. Horses and cattle damage water holes by leaving the soil surface broken and open to erosion, fouling water and spreading weeds.

A better way to go mght be to get historical records (ifavaialable) of what crocs were like before humans arrived in numbers.
Blue

 

[longqi]

Longqi, I have trouble with what is meant by “over populated”. Natural populations are self-limiting according to whatever the limiting resource is. With crocodiles being territorial, the limiting resource tends to be area of suitable habitat. So matter what the food availability, the population is limited by the amount of available habitat. As for feral animals like pigs, buffalo, horses, donkeys and cattle, they compete with native herbivores, such as kangaroo species, reducing their numbers. All up, there is probably not a significant increase in food availability. But even if there is, it is more likely to have an effect on the rate of growth than on ultimate population size.

Estuarine crocodiles in Australia, despite popular belief to the contrary, were NEVER endangered.

Blue

That is correct Blue
In their protected areas ie parks, they are getting to be too many for each area to contain
Unlike other animals they do not limit their numbers
They simply spread out more into less crocodile populated areas
Big males control an area
So smaller males have to move away
This is where the problem lies
Where they are moving to is into areas occupied by humans
Because they have never been threatened by humans they are getting too interested now

 

[Bluetongue1]

As was to be expected, large saltwater crocodiles were common in all rivers of northern Australia at the turn of last century. So crocodiles are not moving into habitats they did not already occupy prior to European settlement.

Firstly, this nothing new. In the 70’s and the 80’s there were a dozen plus fatal croc attacks. Most offenders were shot and killed. Any croc that was involved in a non-fatal attack and could be located, was caught or killed. This includes the NT, Qld and WA. Large numbers of potentially dangerous crocs were and still are removed from populated areas and designated swimming spots every year. Greater access to remote areas through road and tracks and all-terrain vehicles has also brought more contact between crocs and humans and more potentially disastrous scenarios. So yes, the frequency of attacks has increased since protection but has levelled off over the past two decades.

The majority of the fatal attacks and nuisance crocs of the 70’s and 80’s were due to large males – 3.5m to 5m plus e.g. ‘Sweetheart’. These individuals were too big to have developed post protection and were obviously crafty survivors of the 40 odd years of shooting. So they have learned, post protection, that humans and boats no longer pose the same risks.

Calling for a blanket cull and blasting the living daylights out of every croc that is seen is one solution. However, putting limits on human expansion and habitat destruction, while at the same time finding a reasonable balance between our safety and comfort and letting nature exist, is the better long term solution. Remove the hysteria from croc attacks, the vast majority of which are highly avoidable and the result of human stupidity. Compare the 2 lives lost per year to crocs with alcohol, smoking and dietary/exercise related deaths in this country. Makes crocs look feeble....

Blue

 

[Dendrobates]

If this statement were true then there would never have been any incentive for wasting money, time and effort on the shooting of crocs that went on for decades. Secondly, according to the Bureau of Statistics, the deaths due to crocodiles averages 2 per year. Bees are also critical for pollinating billions of dollars worth of food crops. Aspidorhyncha, I believe you have some valid points to make, even though I disagree with some.

Darlyn raised the important point of: What do we mean by “culling”? Without qualifying its meaning it could be anything from open season to selective removal of occasional individuals identified as a danger to human life. I see little point in using the word unless you make its meaning clear.

Longqi, I have trouble with what is meant by “over populated”. Natural populations are self-limiting according to whatever the limiting resource is. With crocodiles being territorial, the limiting resource tends to be area of suitable habitat. So matter what the food availability, the population is limited by the amount of available habitat. As for feral animals like pigs, buffalo, horses, donkeys and cattle, they compete with native herbivores, such as kangaroo species, reducing their numbers. All up, there is probably not a significant increase in food availability. But even if there is, it is more likely to have an effect on the rate of growth than on ultimate population size.

Estuarine crocodiles in Australia, despite popular belief to the contrary, were NEVER endangered.

Blue

I think you've hit the nail on the head with pretty much everything you're saying, Blue. The only thing I need to clear up though is when I was referring to wild crocs never becoming hand bags, etc.. I was referring to nowadays, not when they were culled for decades. These days wild crocs aren't used for fashion, however they most certainly were used back in the day. These days even zoo crocs are rarely used for their skins when they die.. there's no demand for skins with imperfections when perfect farmed skins are available. That's all I had to say.

 

[longqi]

As was to be expected, large saltwater crocodiles were common in all rivers of northern Australia at the turn of last century. So crocodiles are not moving into habitats they did not already occupy prior to European settlement.

Firstly, this nothing new. In the 70’s and the 80’s there were a dozen plus fatal croc attacks. Most offenders were shot and killed. Any croc that was involved in a non-fatal attack and could be located, was caught or killed. This includes the NT, Qld and WA. Large numbers of potentially dangerous crocs were and still are removed from populated areas and designated swimming spots every year. Greater access to remote areas through road and tracks and all-terrain vehicles has also brought more contact between crocs and humans and more potentially disastrous scenarios. So yes, the frequency of attacks has increased since protection but has levelled off over the past two decades.

The majority of the fatal attacks and nuisance crocs of the 70’s and 80’s were due to large males – 3.5m to 5m plus e.g. ‘Sweetheart’. These individuals were too big to have developed post protection and were obviously crafty survivors of the 40 odd years of shooting. So they have learned, post protection, that humans and boats no longer pose the same risks.

Calling for a blanket cull and blasting the living daylights out of every croc that is seen is one solution. However, putting limits on human expansion and habitat destruction, while at the same time finding a reasonable balance between our safety and comfort and letting nature exist, is the better long term solution. Remove the hysteria from croc attacks, the vast majority of which are highly avoidable and the result of human stupidity. Compare the 2 lives lost per year to crocs with alcohol, smoking and dietary/exercise related deaths in this country. Makes crocs look feeble....

Blue

Culling is never blasting the living daylights out of every croc
Culling is removing 'X'% of crocs from an area by whatever means is deemed most practical
This may include shooting trapping or egg removal
Larger numbers of crocs are being removed every year and this number is definitely increasing if you look at Darwin harbour as an easy example
When fearless apex predators return to any area where man is now resident in ever increasing numbers there can be only one outcome
Your reasonable balance has been reached now
But that balance is tipping further every year

 

[Bluetongue1]

Thankyou for qualifying that statement Aspidorhyncha. I learned something new.

Longqi, the reference made to widespread shooting of crocs was a bit of tongue-in-cheek re-phrasing of the mother's call for a 'cull'. Not referring to anything you said.

I know the numbers being removed have increased but have not lked at the figures fr some time. I will do that befre I make a comment.

I will say that egg removal is by far the least effective way to reduce numbers given the number of eggs produced per clutch, the difficulty in locating all nests in a given region and the inherit dangers involved in harvesting the eggs.

Blue

- - - Updated - - -

Data on all croc removal per (financial) year by the NT National Parks and Wildlife Service is provided in the current management plan (1012-14), for the years ending in 998 to 2008: 112, 152, 182, 147, 180, 222, 224, 238, 247, 204. There is a levelling out evident over the second five years.

They monitor croc numbers and biomass (via sampling) in 12 rivers. A quick summary of their findings follows....
The numbers for seven of the twelve rivers suggests that the populations have been stabilising in recent years and are approaching their capacity, while there are still varying rates of increase in the other rivers. Biomass density increased in only six of the twelve rivers, suggesting that the size of individuals has been stabilising in recent years and is approaching carrying capacity in those rivers with no increase.

Crocs will continue to disperse into areas of human habitation. The NT govt. made a bad mistake in declaring there would be a so many kilometres (50 I think) “exclusion zone” around Darwin. The reality is that they cannot guarantee any exclusion due crocs ability to travel over land as well as by water and the fact they can travel substantial distances quickly. One cannot assume that any substantial unfenced body of water is free of crocs and behaviour has to be tailored accordingly – including restricting pets.

Blue