It's hard to watch! I looked out to see two male E. Bluebirds fighting and they seemed to be fighting to the death. Then another male joined in the ruckus, and it was two against one. Then a fourth male flew in and it was a free for all, sometimes all four tumbling on the ground, and sometimes the two pairs fighting one on one. I wanted to run out and separate them, tell them we have plenty of bluebird boxes and to quit fighting. I watched for what was probably only 5 minutes, but it seemed like ages. I even had time to run across the house to get my camera and take a few pictures. Finally a flock of grazing Starlings and Robins took off all at once, and that broke up the fight as the Bluebirds took the cue and flew away too. Tarcila Fox, Goodlettsville, Davidson County TN