They are 4.5 weeks old and spent that time with their MHP cave right? That means they know EXACTLY what the cave is and what it is for. They are likely fully feathered. ASSUMING that the gusty wind can't get to the chicks in the coop, they don't need supplemental heat nor the cave. If the gusty wind CAN get to the chicks, you should fix it so that is no longer true. Chicks or adults, no draft, let alone wind, on the birds in the coop.Okay... I think I need some broody brigade wisdom (or reassurance) (Or maybe just gutsy Blooie)
Last night was my 4 1/2 week old chicks first night outside, and they huddled comfortably under the MHP. Today they were in and out as expected. Now tonight it is gusty and colder than last night by a few degrees (Low 27) and they decided to huddle in the corner together instead of in the MHP, not even near it.
I guess I could use some reassurance that they are not stupid, they know its there, and if they are cold they will use it instead of freezing to death?
Now even though they are fully feathered they might still like to use the cave, especially since it is a familiar object and warm inside. Which then begs the question: "What setting is the pad on"? If you put it on high because it is cold outside, it might be TOO warm inside for fully feathered chicks. Just as they did in the house if the pad is too warm, they won't go in.