What would cause a group of 5 month old pullets to not go in their house for the night, other than red mites? I went outside last evening and all 4 of my girls were roosting in the run, their automatic door was still open. The door closed and then they decided they wanted to go in. I had to physically carry them into hen house. I went back out later with a flashlight and checked for mites, none present. No predators/rats/ect have been in the coop.