It's not just city people that keep their cats indoors. Almost no one where I live (suburban area in northern California) lets their cats out any more, because the cats get eaten by coyotes.
We have a pack of hounds, part of their job is to keep the coyotes off the livestock. We used to keep ~10 acres but have pulled back to about 1ac in the last couple of years. It's been hard on the grey foxes, they've actually moved up closer to our house so our hounds can cover their den; I dunno but they might not be to blame for the loss of at least one of the cats, too.