I have a bantam that looks just like your rescue. We found her walking the streets. Literally. Our neighbor saw this chicken running the street and called to see if it was ours because we were the only people in town with chickens. We said "no" but didn't want anything to happen to her so my wife and some neighborhood kids caught her and brought her home. She lays little white eggs and tells the whole neighborhood about it when she does. At the time we got her, we didn't know of any others who kept chickens in our town. Since then we have began hearing at least four other roosters crowing around.