Everyone has different situations. Some critters can climb up wire. I had a pen with a 5 foot fence and a coyote jumped over the fence. Some of the birds were so frightened they went over the fence. The coyote jumped back out and was chasing the birds around and killed some. I had my shotgun handy and got off a shot of bird shot. I'm sure I hit him but didn't kill him. He ran off. After that I put electric wire around my coops and pens. I covered them partly because I had an owl kill some birds and cement under the gates after a fox dug under a gate and killed some birds. Predators are everywhere and love chicken. Good luck and have fun...