In the place we just moved to earlier this year, it cannot be expanded to the east any further (thank God) because it is adjacent to an eagle's nesting area. We had my son's cat, who loved to go outside, here for about a month before he disappeared. We checked every single road in a 1.5 mile radius and not a trace, although it was probably a waste of time anyway because it's not anywhere near a high-traffic area.
Not a big fan of cats at all, but I don't like thinking about the likelihood that he was snatched up by one of those eagles or even one of the owls that I hear at night.