I spent a little time yesterday afternoon (roughly 2:30-4) at Chain Bridge & the platform just north of it. A nice selection of raptors, though no large numbers. From the bridge: The usual Turkey Vultures and a Red-tailed Hawk overhead; a very cooperative male American Kestrel hunting the ponds down below; a Sharpie over the trees to the northwest and a probable Red-shouldered (too far away for me to be sure) being harassed by crows in the direction of Dalecarlia Reservoir. >From the platform: A Cooper's flew up from a tree just ahead of me, and I of course had been looking for sparrows in the underbrush. Then another -- or the same -- probable Red-shouldered perched in the trees to the east, clearly visible from the platform but too far away for a good i.d. Then invisible once I returned to the towpath. Also the usual Great Blue Herons, Mallards (no wood ducks), Canada Geese, a lone Ring-billed Duck, Goldfinches, etc.