Coyotes are good jumpers. They can get over a 6' fence. We never know how secure our runs are, until they are proven to be not secure enough. My vote is coyote, though, FYI, trees do not stop hawks or owls at all. I hope your hen is just hiding, and shows back up, but I doubt that she has gone broody, from the description of the commotion and your pullet being outside the fence.Yes, that's just what I was thinking, we have lots of coyotes (and heard them again last night). But I don't think a coyote could get over a stake/wire fence without any damage.