No amount of trying to reason with these morons would stop them. So on advice of the sheriff I shot and buried every last one of their lousy invasive-species pets. Collared or not. Even as I was shooting hundreds of cats they kept adopting and releasing MORE of them. Those too eventually shot and buried, until my land was 100% cat-free. The wildlife has been coming back now that the cats are gone, for over 2 years.
Until recently. When the same morons adopted 5 more cats last week. They must have thought since they didn't hear any gunshots for 2 years it was safe to release some more of these destructive invasive-species. WRONG. Those too were swiftly shot and buried. The land is once again 100% invasive-species-cat-free. Some idiots never learn.
Interesting note: One winter I tried feeding one of the shot-dead cats on my land to the last few starving opossum (all the rest of my larger native wildlife starved to death from cats destroying all their food sources). Those opossum promptly died from some disease in that cat-meat. Alarming -- in that opossum, due to their cooler body temperatures, cannot contract nor transmit many common diseases, not even rabies. They are one of the most disease-free animals in N. America. Yet ... something in that cat-meat was able to kill them all. Cats truly are complete and total wastes of flesh. They can't even be used to feed wild animals safely. Leaving any of these invasive-species cats out in nature, alive OR dead, is no better than intentionally poisoning your native wildlife to death.