Originally posted by The Blue Meanie
In fact, it would actually be BETTER if they fixed the cats and release them, than if they just caughts and killed them. Here's why:

If you catch and kill the cats, then that means that every cat still in the wild can still breed. Therefore, every time any of the cats mate, there's the normal chance that they are going to have babies. IE, a high chance.
Oh I agree with you entirely - sterilisation is a much more effective way of controlling a population, not only do you have the wasted reproductive effort, but you have steady competition for resources. For small, concentrated populations it is quite viable, but it becomes totally impractical in the areas that they are doing the most damage in. Feral cats are not just a problem in small wildlife parks close to cities, they're a problem across millions of acres of unpopulated, isolated outback. Yeah, maybe a tagging and sterilisation programme would be possible with millions of dollars of funding, but unfortunately those millions of dollars are non-existent. While it would be nice to refuse to do it on moral grounds, I think that if people are willing to accept the death of animals to give them a nice juicy steak on their plate, then the death of animals to prevent the excintion of species and irreprable damage to the environment shouldn't be much of a problem.