Our chickens have always put themselves up at dusk. We go out and close the door to their house. Recently we put up a light in the chickens area. That night I was a little late closing the door. Went out about 10 pm and to my surprise they were all still out. The light was attracting bugs and they were picking them off. It is brown beetle time around here in Tennessee. The beetle makes a unique noise as they hit the wall and fall to the ground. They have been doing this for a week now.