I lost my favorite bared rock about 6 weeks ago, just vanished to sign of her, not a feather. I have a secure pen inside a large fenced in back yard, 4'chain link. I just got 4 new black astorlorpes, had them about a week. Have just started letting them free range during the day. Yesterday found one of them headless and half eaten right next to the fence in a sheltered corner where they all love to hang out. Found her about 3PM, so this definitely happened in daylight. All the rest of the flock where hanging together up near the house with the exception of one who was hunkered down in another part of the yard I guess terrified. I rounded them all up as it was getting close to the time they go in anyway and put them in the pen. Now I'm afraid to let them out of the pen and I hate that. I have a large wooded back yard that they LOVE to roam and scratch and peck. I did walk the perimeter of the fence and found a opening at the bottom very close to where the bird was killed. I would love to know if everyone thinks this could be a fox? Several suggestions I've had are to set traps, run electric wire at top and bottom of fence, or of course leave them in the pen. There are in the pen until I figure this out. Any advice would be appreciated. Thanks!