My birds free range during the day, and I close up the coop at night....but sometimes I forget to latch the door. I won't forget again. We've not had a single predator in 3 years, until last night. This morning I went out and my 4 largest birds are missing. Nothing left but a very few feathers, no trace of blood. We have snow outside the coop, and a dusting on the coop floor, and there are no prints, not even chicken prints. I can still see my footprints from last evening though. They must have been snatched from their roosts? What could so easily take 4 very large chickens? I've been sketching plans for a run. It was going o be a tall fence, but now I'm thinking enclosure.