Why do my chickens roost at the normal time and then get wanderlust in the middle of the night? I have been out to my chicken pen and find chickens just wandering around at all hours of the night. They are not at all nervous or upset. (I don't think anything is attacking them. I have not noticed anyone missing) They eventually go back to bed but then they are up again hours before daylight wandering around. Is this normal? I have many pens and only one pen has the wanderers.