I originally posted this as another in a series of pictures of a regular visitor to our backyard, a year-old male Cooper's Hawk in the process of molting from juvenal to first basic plumage (see http://www.pbase.com/tgrey/coopers_fountain .) Siobhan Ruck convinced me that this was in fact a different Cooper's Hawk, an adult female. Siobhan wrote that "the brown feathers look like faded adult feathers from the previous year, rather than the last of her juvenile feathers. Juvenile feathers usually retain a bit of a rufous edge and frequently have some white splotches at the base (this shows well in the photo of 8/6). Female coops have a warmer grey back plumage, and faded adult feathers often look brownish compared to fresh feathers. Male coops have that really steel-blue grey color, so even faded feathers keep the cooler tones." So we've had a second coop visiting our backyard fountain this summer!