Preditory birds are a major problem for me. I had a sharpshin hawk who decided he liked pigeon, racing pigeons to be exact. Got to the point I was down to 4 birds. Then the hawk decided to follow the pigeons through the traps and into the loft where it dinned on 2 more. I was down to my last pair. The Hawk, BTW, is no longer a nuance to my neighborhood. I am now slowly building my bird population back up--have 5 now.
Just had a banty hen hatch the only egg she was sitting one but I don't want to loose the chick to hawks.
In my area we have Bald eagles, Ospreys, Goshawks, Pereguin falcons, sharpshins, Red Tailed hawks, Sparrow hawks (which prey on bees and flying insects), Coopers hawks, several other variety of hawks as well as vultures, and several types of owls. I can hardly go outside without seeing a bird of prey.
The only birds that dine on the flying bees are the Sparrow hawks and once in awhile the barn swallows. The swallows, most of the time, fly near the water retention pond for the development next door scooping up misquitoes. Since I'm the only one in the neighborhood who still has a barn I get to host the swallows.
I must admit thought that the crows and ravens do a fairly good job of harassing and keeping the larger birds of prey far enough away that they don't bother my birds too much.