I am also concearned about my ducks getting cold as it get's closer to winter, I have read that Runners can handle the cold weather. Marysville Wa get's mild winters but it can dip down to the 20's sometimes. So far we have an insulated plastic dog house in their pen. I have it filled with straw for now. I was wondering if I would need to provide a door and or a light for some warmth during winter? I also considered taking the dog house off the ground and resting it on a couple of fence posts.