My husband noticed some strange behavior tonight not long before our 6 chicks (8 weeks old) went to roost. They were randomly roaming the yard, when they all suddenly froze in their tracks for nearly a full minute. They were somewhat scattered and not looking at the sky as they've done before when spotting a hawk. Just frozen in their tracks. We're in the middle of a neighborhood, so no unusual wildlife nearby. When they finally moved again they ran to the corner of the garage to huddle under a bench. Any clues to offer this newbie to chicken keeping?