This is my first winter with chickens. I have five barred rocks hatched late May. They have a smallish coop but sufficient, and plenty of run space. I'm comfortable with dealing with the cold weather from a "protect my hens" point of view. But I'm curious about their natural behavior outside when the temp drops. How low does the temp have to be before they start seeking refuge in the coop? So far they've spent every day outside, but we've onlybhad daytime temps below freezing one time for bout two days. Our average high is usually in the 30s but for the last few years we've had some extreme cold, daytime highs in the teens for long stretches at a time. Not sure what we're going to get this year but want to know what's normal for the birds in the colder sub- freezing temps. Thanks.