I'd like to build a coop that holds about 12 chickens during the night. During the day, I'd like them to be able to run around, either totally free over 15 acres or confined to a large fenced-in space, (no roof). I see hawks and hear owls all the time. Foxes come through once in a while. I suppose once a year, a coyote may tour the land as well. The land is a vegetable farm in Illinois near Chicago in the middle of a suburb with over 140,000 people. Does anyone have some advice about whether or not we could free-range during the day? Are there too many predators? What about in the cold winter--can the chickens still come out? Thanks!