I see you can get 1320 feet of barbwire from $40.00 at Tractor Supply. What if you put barbwire around your pen at 3 inches high, at 6 inches off the ground, at 12 inches off the ground, and again at 18 inches off the ground. That should slice up any ground roaming predator that dares come near your pen! That way you don't have to even use electricity for an electric fence or netting or buy an expensive charger. You could disguise it with some pretty flowers, shrubs or roses too. I think I will do that!