those beaks don't look like raptors'. it's hard to tell what species.
my first impression was mourning doves, because shape, colour, and beaks.
but the screen could be obscuring too much.
@holon42 These things are twice as big as doves, and every bird near the feeders skedaddles when they hop by.
oh, they fly away completely, or just make room?
if they're that big, then i don't know. it's the beaks that puzzle me, but, as i said, maybe the screen is obscuring the actual shape.