We are starting over this spring. Two years ago we lost hens to foxs so we improved the run bottom. This last year we kept lossing a hen a night and couldn't find feather or foot. Then I moved the chickens up next to the house. I am taking a shower when I hear a hen "awkkkk" outside the window. The only other sound was that of "whoosh". We had everything covered except the top. Found the owls perch the next evening. He had to be almost 2 feet tall. I have a better pen ready this year.