Whether "true" or not, we do have feral chickens in Hawaii. Mostly on Kauai, where the mongoose introduction was initially foiled by a sensible man who knew what they would do to the native birds and tossed the crate of mongoose in the harbor when they arrived.My point, however, is that they thrive where there is cover - dense underbrush and trees. If you have that, you have some chance. Here our main predators are dogs, and they are a real problem. I gave up my free range dreams and got an electric mesh run.see my byc page.