Typical of me, I will completely sidestep your question with some other answer ------- The boids around here are singing constantly. I have lotsa trees, bushes, and they even like the wild briars to nest in. There are all kinds of things to eat. Plenty of tasty bugs and worms. I built 30 odd birdhouses for the unskilled nest builders such as the occasional Bluebird. Hawks are seen perched on top of telephone poles and every once in a while, they swoop down and kill a robin. Plenty of cardinals, too. None have tried to hold Mass yet.