Very intersting info K9, thanks. BUT along with the many reports, I have seen with my own eyes one cat that was dingo size (med size dog for non aussies) & my husband has seen a couple of monsters in the outback(Kimberley & Pilbara). Thats not looking for them, he saw driving, i saw horse riding. So while i agree theyre generally not that big & maybe depends where they live & how many generations, they cant be that out of the ordinary. Perhaps in your region they not that big - ive never seen anything of the sort down here, only up nth.
Hear hear about mandatory spay/neuter - while registration of dogs & cats is cheaper if theyre fixed, thats no real deterrant let alone answer & IMO it should be illegal to keep an intact beast without a permit/license to breed. I agree too that without that measure of course its not permanent to cull. Im very interested & surprised to hear about feeding programs & that they are effective at reducing wildlife decimation - i would have thought that would just encourage more to breed/thrive. Where abouts is this program running?
There very well could be larger cats, but like I said those are NOT the norm. Larger feral cats tend not to have a better survive-ability rate. If, indeed, that image and the cats you are seeing are real, I am about 99% sure they are somebody's pets and are NOT feral cats (at the very most they are abandoned pets). Feral cats would die before they reached that size as they are not as inconspicuous in larger sizes and thus are more likely to be picked off by predators, hit by cars, killed by people, etc. Also, larger size means they must consume more food and water.
In a lot of cities and counties (and the number is rising all the time) in the United States (and many other countries around the world) there are mandatory spay/neuter laws where you must pay yearly to have a special permit and license in order to keep your dog or cat intact, and you must pay an additional litter permit (per litter) if you breed your female, even if it is an unplanned litter. It is also illegal in many places for dogs and cats to be off of your property unless on leash or confined in a carrier, and it is mandatory for them to be microchipped in case they are found loose off of your property.
When I was an ACO up in ABQ, we did spay/neuter "blitzes" (large reduced rate spay/neuter, vaccination, and microchip mobile clinics) in low income areas and then did yearly statistical analysis and we saw a dramatic drop in cruelty calls, abandoned animals, stray calls, etc. in the areas where we did the blitzes. We also had a successful TNR program going for the feral cats all over the city and had logs of all feral cat colonies in the entire city. We kept a list of all volunteers who monitored the cats, fed them, and trapped them to bring them in for spay/neuter, and officers and volunteers from the TNR community and other cat rescues and groups in the area did educational seminars and workshops for the public about the benefits of TNR. The TNR program cut down on the feral cat population dramatically and helped the people/cats coexist more peacefully. Due to strict laws upholding that pet cats are not allowed off of your property, feral cats (whose ears were tipped after being fixed) kept to their colony areas which were in generally urban areas where little wildlife was found, thus this helped prevent songbird killings. During my time as an ACO, we received little, if any, complaints from the public about the feral cat colonies and their presence in the community. If anything, the city received immense support from the community (including from the birding community) for the TNR programs.
As others have said, the problem stems from people. People have created this problem, and now are scrambling to fix it and again they are only looking at a temporary solution rather than a permanent solution. Education goes a long way to help with a permanent fix, and initiating a mandatory spay/neuter, intact permits/licensing laws, restrictions on off leash/property for cats and dogs, and setting up a TNR program is the beginning to help curb the problem in a more permanent and humane way.
If you would like more information about TNR and feral cat populations, one of the best sources is
Alley Cat Allies.