I'm lucky enough to live on a major Red Tail migration fly way on the north shore of Lake Erie. Every fall we have hundreds of them around every day.
During the summer the sparrows take over everything and flock my feeders. In the fall I have a Sharp Shinned Hawk that moves in and knocks the sparrow population down leaving room for the cardinals, finchs, nuthatchs, and chickadees. That hawk stays all winter and likes to perch on the front porch railing. I can always tell when he's around by the seed consumption. Sure controls the aggressive sparrow herd. For some reason he seems to prefer the sparrows and I've never seen him hit anything else.