I had six birds raised from chicks since May. They were happily free ranging during the day and locked in the coop at night. One day three went on an "adventure". I don't know what nabbed them mid day but it was very sad. We are closing in on October and I worry that three birds in the coop won't stay cozy. I've made inquiry's about bringing 3-4 mature hens into the flock. I know I have to keep new birds quarantined for weeks outside the coop. Is it worth it or can three birds stay warm through the winter in a moderate sized coop?