A spring-like day had the Bluebirds checking out possible nesting locations. They explored all the houses in the yard and went in and out. I am not sure what was going on with this trio. They explored each box as a trio with each going in and out of the box. I have heard that previous generations will help raise the young so I am thinking one of the trio is a previous offspring.
They seem to like this box however this is one I was going to replace this year. It was one purchased at one of the big box stores and is actually a poor design. There is a gap at the top in the back that might allow water in during a heavy rain resulting in nestlings drowning. The gentleman who is head of the local Bluebird Society states these are not good boxes because of that. I think it is more the location they like so will get a new box this week.
If you live in NC, the State Employees Credit Union has well made and designed boxes for sale at a bargain price. You can't beat them. It is a cooperative effort to help provide nesting boxes. A lot of folks may not be aware that the Eastern Bluebird numbers had once declined to dangerously low levels due to habitat loss.
After watching one of the new boxes at a new location, I think I will move it. The Bluebirds seem to like to exit the box over grass areas versus a more wooded area.