As Howard E stated, coons can rip right through the chicken wire. I learned the hard way on that when I first started keeping chickens. Then two years ago I had to stop letting my birds free range and had to 100% enclose my chicken yard after loosing several hens to a fox attack middle of the day. I watched as it easily jumped my 6 foot horse fence. Where there is a will there is a way and they will exploit any weakness.
