We have a resident fox also every spring I assume when she has kits she will come under the smallest space under the fence and take a whole chicken no wasted food for her. The dog has really solved that problem too without shooting, trapping or killing the fox.
I have a racoon family that used to come eat catfood. One night I looked out my porch door and she had 7 very small babies with her. Then the chicken slaughter started. A full belly of catfood wasn't good enough. She killed chickens for the fun of it leaving headless bodies strewn about...