Was she ever at the low end of the pecking order? I’ve got a hen that’s pretty far down the pecking order and she has attacked in a really aggressive manner. We built another roosting area and she claimed it within the first couple days. When the queen hen tried to get in the new area, this hen attacked her like a crazed chicken. It was totally out of her normal behavior.But why kill the other hen?
Anyway, just an example of craziness to think about.