I've got 4 Narragansetts that are 15 weeks old. They are roosting on top of the chicken coop like they have for the last few weeks, even though they have access to both the chicken coop and another coop. Tonight is supposed to be our first night significantly below freezing. Forecast suggests around 20°F and windy but dry. Should I go out and move them in a coop or will they be OK?