Return of the falcon (sounds better than hawk, but is not taxonomically correct)

I was in my front yard yesterday, trying to remove the dead limb from a small tree, when all of a sudden there was a big commotion in the impromptu birdbath a bunch of robins and swallows had made out of uneven portion of the sidewalk.  I looked over just in time to see a beautiful grey bird swoop down and make a screeching sound, causing all the smaller birds to get the hell out of Dodge.  Not to suggest that my yard is the wild west, but there are a bunch of interesting critters that make appearances in my neighborhood.

[borrowed from Cornell, photographed/copyrighted  by Gerrit Vyn]

The most common are black or grey squirrels, redpolls, sparrows, morning doves, cardinals, wood peckers and the occasional possum, pheasant or rabbit.

In trying to identify my bird of prey from yesterday, I came across two websites which were helpful.  I a sure there are very more, but I only have SO much time to indulge in web surfing per day.  The better one was from the Cornell Lab of Ornithology, and can be reached here.  Another good one is a more local page from the Illinois Raptor Center.  It has some good explanations, but does not have all the bells and whistles of the Cornell page.

The way in which I think this fits with the "Don't mess with me (or my friends)" theme is that even though the hawk was outnumbered at least 10:1, as soon as announced its presence the other birds undoubtedly knew who was the boss!