I had the pleasure of watching a pair of Carolina Wrens prepare their nest in one of the birdhouses yesterday. They raised a brood in the same birdhouse about this time last year. There's a brand new birdhouse in our back yard but they chose the old one. I call it a bird "townhouse", and they chose the most dilapidated house. I figure maybe it's because the cracks on the side allow for more ventilation. I don't know. We are all creatures of habit, aren't we? I watched them for about an hour or so, flying back and forth, gathering sticks and leaves to cushion and protect their forthcoming eggs. They worked as a team. Sometimes Dad wren would take a break and perch on top during which time he'd sing. It's incredible to hear such a loud song coming from this tiny bird.
The last photo is NOT a Carolina Wren. It's a Chipping Sparrow that decided to check out the activity going on at the bird townhouse. He didn't seem all that impressed so he didn't hang around for long.