Hello. I had small flock of 6 chickens. 5 weeks ago I found one of them dead on the floor of the run. There was a large hole eaten into her abdomen. The upper coop and the run looked like Armageddon had hit with feathers everywhere. I found a few fist sized holes in the fencing around the run which I have since sealed up. I have since added three 22 week Rhode Island Red mixes. In the past 5 weeks I have not had a single egg produced. By any of them. (The others are 1 1/2 years old and have been excellent producers) The days have been shorter and I have not supplemented with light. This morning, I found my (head of the pack) hen dead in the upper coop with NO apparent injury whatsoever and a few of her feathers strewn about. She was by far the healthiest, most aggressive and largest of the flock. I also noticed one of the smaller girls had a clear white/brown mixed mucus looking stool this am. The coop was RE-sealed up this morning (again, a few fist sized holes in the perimeter) and they all look healthy (feathers, appetite, energy) Lots of info here and many pieces of a puzzle. Any advice out there?