Here in So Colorado at 7500 feet, I'm having a thirteen below morning. My girls are huddled on the ground or on perches and not interested in eating the hot oatmeal I served them. One rooster is in his coop with the heat lamp on and refusing to come out at all. The other roo is out in his plastic shrouded pen monitoring the girls on the other side in their plastic-covered pen. They're all protected from the wind-chill, but it's still thirteen-below. Do I need to worry about frost bite?