Wendy, what ate my chickens? (It was accompanied by pictures)
From the hole size, I'd guess a skunk. What got the chickens is not the most important question to ask. How to make the coop stronger is what you need to know.
As you can see, the bricks around the outside of the pen were simply pushed aside. From there, it was an easy dig on soft soil to enter the coop.
What works for me is to have a woven wire bottom on the ground where the pen will go. That bottom extends some from the side of the pen. If I do not do that, I ring the outside of the pen with chicken wire folded in half. Half goes on the ground and half goes against the pen's wall going away from the pen. This way, if the predator runs up to the pen and begins to dig, it digs on the wire.
All of my pens for poultry also have woven wire fencing or chicken wire on the top. Not only do we livestock owners have to worry about ground attacks, but air raids from predator birds are a real threat.
I also keep a dog in a large run near my poultry. This has been very, very effective. I'd say it was one of the best things I have done with our livestock.
For the pens that border our wooded areas, I use predator lights that mimic predator eyes and motion solar lights.
I also ask my menfolk to urinate around the pen. The smell does seem to be a deterrent. When I have employed this technique where I have had multiple strikes, the losses stopped. We are blessed that no one is close by and our men can do this. Friends have their men urinate in a bucket and they pour that around. Eons ago, I read it was the testosterone in the male urine that makes the predator go away. In other words, the predator knows the human has laid claim to and will defend the area because of the scent marking.
Every once in a while, something still gets taken by a predator. Our geese free-range and we have goslings waddling about the acres. One was taken recently. I saw a very large fox in the driveway, so I believe it is the culprit. Something also struck the outdoor aviary and took a few parakeets. It had to have been something fairly small like a young weasel. The only entry point I saw was a very small area at the corner of the door. To give you an idea, the manufacturer made a square opening for a rounded door. I will be working to tighten up that pen this week.
I believe we should live with nature as much as we can, but I also believe in dealing with problem animals. My livestock count on me taking responsibility for their safety. The predator is working against that. Generally, I will ignore one gosling being taken, but if it becomes a problem, I start setting traps. Anytime I have something taken by a predator, I alert my neighbors so they can watch out for their livestock also. They appreciate it and often offer to help out.