I found this crazy prevention. It may sound ridiculous but I'm going to try it if a fox ever comes around. Go to a hair dresser and ask for a chunk of cut hair (or you can just cut your own). Then you put the hair in a sock or some breathable material then hang it some where in your run or in your nest boxes or in you roost (make sure it's under cover). This is to PREVENT FOXES.lol. The smell of human deters foxes from coming to your run and your hair reeks of human (would you believe). I thought you could make a scare crow and stuff it with hair then the fox would have to back off. If you have foxes try this and then update us if actually works.