A house wren has moved into one of the houses in my yard and bluebirds into the second house. I think the wren finally has a mate because I often see two of them going in and out. However, no eggs yet, although the nest has grown to gigantic proportions! Now the nest is lined with feathers, so perhaps they are preparing for eggs. Trust me (I stuck my finger into the nest cup - it is quite deep) and it is soft and totally feather-lined. See how close the nest comes to the top of the nestbox? It's huge!
Mr. & Mrs. Bluebird have a clutch of five eggs. I couldn't get the camera all the way into the box, so you can only see two of the eggs in this picture. The bluebirds incubate most of the morning and evening, but in the heat of the day, they leave the eggs alone. Aren't they a beautiful shade of blue? And so tiny.