Fox are difficult to trap in a live trap!
My coop and run are now one unit, roofed, and pretty safe. It took years to achieve this, and it's been wonderful.
It is a work in progress; last winter/spring rats invaded the coop, ate eggs, and killed three nice bantam pullets. This winter there's been a mouse population explosion! I have had to place poison out there, in a separate area, really something that I hate to do. Things are better now! In spring, it's time to pour a new concrete floor out there. Much too cold now!
I hope you get your varmit(s)!
Mary