Wow! There's only one house/block fence from open desert here from our house here in Maricopa, after that is the Maricopa/Casa Grande Highway, which we call the McG ;-) Then the train tracks and open desert for miles and miles and miles. I don't think the cats run open desert, I know coyotes do, we hear them all the time. But I'm a little worried now that a cat came in your yard. We have a doggie door, and our two goldens go in and out at will. I've felt completely secure with a wall and a lock on our gate, now I'm freaking out a little. My dogs are on the bigger side, 75lbs and 90lbs, but jees, I trained all the mean out of them, they're therapy dogs... I think a mean domestic kitty could hurt them now. LOL (I hope). I know you live a long way from me, but I listen to the coyotes every night howling at the train and can hear when they catch "something" for dinner. I always knew a coyote would never climb a fence just to fight a dog 50lbs bigger, but a cat might.... good grief, I'm going to have nightmares.