A secondary question would be to ask how Australians count the number of feral cats in Australia. To this question there is no answer. And therefore, the guesstimate that there are about 2.7 million feral cats in Australia is simply that, a guesstimate. It has probably been worked out by extrapolating the numbers from small-scale studies in various districts of Australia. This is inaccurate. What is also inaccurate is the estimated number of prey animals that feral cats kill annually. The problem is that inaccurate figures become fact in time because the people who write articles for websites on the Internet constantly reproduce these figures. In this way you can turn fiction into fact if you are not careful.
It should be noted that it is difficult to work out the population size of any cat species including, for instance, tigers. How do you do it? Answer: camera traps, counting scats (feces) and visual sightings. All are slight problematic at best.
And if you don’t know the true number of feral cats in Australia you also don’t know the number of animals they kill. And people don’t know the number of animals that humans kill in Australia through direct action or indirect action by their behaviour including global warming and commercial enterprises which destroys habitat.
I think people should be very cautious when reading about these scientifically arrived-at numbers. The Internet can be a dangerous place in this respect. Wikipedia refers to a study by stating that there are 2.7 million feral cats on the continent of Australia. That study is called “Enumerating a continental-scale threat: how many feral cats are in Australia?”
I checked out that study. They say they worked the number out by collating 91 studies. In other words, they joined together 91 studies on feral cats and made their estimate from those. They also state that the number fluctuates between 2.1 and 6.3 million depending upon rainfall (antecedent rainfall). They say that feral cat density is high on small islands and in arid/semi-arid areas after rain.
In the abstract of the study, they say that they “extrapolate from this analysis to estimate that the feral cat population fluctuates between 1.4 million after continent-wide droughts to 5.6 million after extensive wet periods.”
They also estimate that another 0.7 million feral cats live in areas where there is intensive farming, rubbish dumps and urban areas.
The sub-question to the one I’ve already asked is how did the scientists who conducted these 91 feral cat studies estimate the number of feral cats? I can’t find a reference to those studies but you will find that they are just that, estimates. And therefore, this so-called definitive study is an estimate based upon estimates. Not very sound science.
I’m not saying that the 2.7 million number is incorrect. I’m just saying that it should be read with caution.
SOME MORE ON AUSTRALIA’S FERAL CATS:
You can see I disagree with the way Australians deal with feral cats while ignoring what they do to destroy wildlife.
