I need help IDing a duck. It was slightly larger than a mallard, had a pink bill with black/brown mottling/ had a black head with a white ring around the eye, a white ring around its neck, a light grey back, its legs seemed to be set further back on its body than the mallard (which leads me to believe it may be a diving duck?) and were a brownish grey color, and its tail was fairly wide and stuck up like a ruddy duck, but it was WAY bigger than a ruddy duck and other than the tail, looked nothing like a ruddy duck. It was the only one of its kind with some local mallards (4-5 drakes in eclipse plumage, 4-5 females, and about 5 or 6 of this year's juveniles), in a slow moving small creek (maybe 20-30 ft across and maybe 3 ft deep at the deepest). Can't figure out what this duck is, maybe a hybrid, a juvenile, or a drake in eclipse plumage, or some combination??? Any help or directions to who (or where) I should go for help would be appreciated!