I have a large run enclosed with wire fencing, and I've run a hot wire about 6 inches or so from the bottom. My farmer neighbor down the road thinks that is sufficient protection, but then, he is more complacent about losing chickens to predators than I am. Had an interesting skunk encounter last night, and a skunk somehow got INSIDE the yard. I don't know how. It didn't dig under the fence (I have a four foot wide "path" of a wire fence laid on the ground running all along the fence line and wired to the upright fence (lost a previous flock to a dog that dug under). Skunks supposedly don't climb or are poor climbers. Do I need to run a second wire along the top? Really don't want to....thanks for the advice.