lol, sorry--"battle-axe hen" is just a name I have for those hens that you've had around long enough that they're "tough old birds"--not the prettiest any more, don't lay a lot of eggs, never one to pick a fight (but definitely the one to finish it should some young chick try to take her...
I've had mink attack in broad daylight running through the long grass right past me. Also had hawks and an injured owl attack while I was standing right there. I've also had owls do very scary "fly-bys" at my Pomeranian dog at night! That was really, really creepy as you could feel the air...
It could be either a weasel, mink or bird of prey.
They often attack the vent area of chickens, ducks and geese, pulling their "innards" out through the vent. If this is the case, you need to cull the bird, there's really not much that can be done.
And, most of all you need to prevent...