We have bears that come around once in a while. With chickens we are certain that eventually they will just demolish the run and coop. Whe we built the run and coop we made it predator proof for everything except bears. For that we use a perimeter fence that is electric and goes completely aroung the run and coop. It uses our existing electric in the coop and is on metal T-posts with insulators. I have five wires beginning at 6 inches, up to 40 inches. Three of the wires are hot and the other two are grounds. I just completed the electric fence today so I do not have pictures but if you want more info I will be glad to help.
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