Yesterday I was at a retention pond in Lake Mary, FL. It's surrounded on three sides by trees, and it's a nice place to look for birds and other wildlife. As I walked around the far end of the pond, I heard the call of a Red-tailed Hawk just above my head. I raised my camera and took a few pictures. Then I realized it wasn't just flying by; it was circling me. I looked around in the pine trees around me, and sure enough, there was a large nest near the top of one of the taller trees. I walked away from the nesting site, and the hawk perched in a tree again, though its eyes followed me as I walked away.
Red-tailed Hawks aggressively defend their nesting sites. So if you see this kind of behavior, there's a good chance you need to back away from a nearby tree. For the photographs, I was shooting straight up into the sky, so even though the bottom of the hawk's wings are lightly colored, I over exposed these photographs by about 2/3 stops.
I absolutely adore hearing the call of Red-tailed Hawks, to me the call empitomizes the words "wild and free". Very nice of you to back away from the nest, some unscrupulous people might not. Nice work on the images Scott!