When walking back up I saw many American Robins and Blue Jays in the bare trees lining the road and the adjacent meadow. Suddenly I was stopped short by the unmistakable squeals of a Red-tailed Hawk which seemed to come from a mixed thicket of young pines and deciduous trees off the path. Robins kept flying into the pines and out of view. The squeals kept coming and then, just as suddenly, stopped. The Robins reemerged unscathed and flew off. I never saw a hawk and I am wondering whether the cries came from a Blue Jay practicing his hawk imitation, but I'll never know.