We put this nesting box up several years ago and they said it might take a few years before the bluebirds might use it. Well this year finally, someone moved in and set up a nursery.
I'll not bother it anymore even when (if) I hear baby birds chirping.
It is kind of cramped in there but I guess this is what bluebirds like.
I just wonder how she could pop out four eggs? She's not that big it seems.
The eggs are about the size of your purple table grapes.
Notice the head of the Phillips head screw to get an idea.