Our two Golden Comets have started to lay their eggs in the main part of the coop (chicken tractor) instead of the nest boxes. They have been laying regularly in the nest boxes up until two days ago. Two days ago I found one egg in a nest box, yesterday nothing, today nothing. So I took the door off the side of the tractor and there were 5 eggs laying on the floor of the main part of the coop. Any idea what would suddenly make them stop using the nest boxes?