Robert Ridgway (July 2, 1850 – March 25, 1929) was an American ornithologist. Ridgway was a protégé of zoologist Spencer Fullerton Baird, who, on becoming the secretary of the Smithsonian Institution, appointed Ridgway the first full-time curator of birds at the United States National Museum. He served from 1880 until his death in 1929. Ridgway also published one of the first and most important color system for bird identification, with his 1886 book A Nomenclature of Colors for Naturalists. In 1912 he self-published a larger work on color nomenclature, Color Standards and Color Nomenclature, financed using money from his friend and colleague José Castulo Zeledón of Costa Rica. Ornithologists all over the world continue to cite Ridgway's color studies and books.