There is a perfectly good Wren house hanging in my tree that has never been inhabited. Today, I spent a couple of hours watching this House Wren build a nest in an old bird house that is hanging too low to the ground and has too big of an opening. My Dad made this years ago and I really just hung it for decorative purposes.....not even Sparrows have nested in it. I read that the male Wren builds several nests in hopes that the female will choose one of them. I hope she doesn't choose this one because our neighborhood black cat will be after them. As they say, it's all about location, location, location.
Here the Wren is trying to get a stick into a too small hole...finally he maneuvers it in successfully.
I will keep an eye out to see if the couple does nest here. It would be nice to have them in the yard because they have a sweet bird song. (by the way, no female Wren in sight)