We have a bluebird house in our backyard about 50ft from the back of our house which has been pretty productive for several years. Really enjoyed watching young birds fledge from the nest twice last year. But now we seem to have created a problem that we need some help/advice with. The back of our house is a "Keeping Room" sort of like a Florida room. We had all the windows in the house replaced last year and opted to replace the double hung windows in the keeping room with simple picture windows. Well, the dominate male bluebird has decided that he has a competitor lurking in the reflection from the picture windows and regularly spends a considerable part of his day banging on the windows. I think he had a mate last spring but when it came time to assist feeding the hatchlings he was still preoccupied with attacking the windows so don't know if the little ones made it, or even if there were any little ones; we never saw them. Since then it does not appear that he has been able to attract a mate. So I'm wondering if anyone else has had this sort of an experience, and if there is anything practical that we can do. Thanks for any help. Joe