The Life of a Birdbath Bird

So we have some birds on our block that are bullies. On our new birdbath there are 2 stone birds that attach. I guess a bird or birds don't like them. Everyday since we got it, I have come home to find one on the ground. Yesterday I came home, there were feathers on the ground like there had been a battle. Today I come home, once again it's on the ground and now broke. I wish I had an outside camera. These past few days would have been something to see.