We have an 18 square foot coop with 4 nesting boxes. We currently have 3 "hens" and 1 duck, all about 8 weeks old. They free range on 5 acres during the day, though they stay very close right now. How many more chickens/ducks can we get comfortably? We get a ton of snow in the winter, will they stay in the coop during the winter? I am loving them so much, I think I could easily become a "crazy chicken lady" but don't want them to be too crowded in the winter.