ravens are very intelligent birds. we moved our chickens several times, trying to evade the ravens. we had them in the forest under chicken fencing, surrounded by electric chicken fence. we even put out fake owls and spinning wind wheels to deter them. nothing worked. the ravens still found a weakness and exploited it. They killed 9% of our flock. since i hung the raven from the tree no other ravens have been around to bother the chickens