Birdlife International split Swainson's Thrush Catharus ustulatus into Swainson's Thrush C. swainsoni and Russet-backed Thrush C. ustulatus with this latter breeding on the west coast of North America and overwintering in Central America. The BI Swainson's Thrush breeds in North America and overwinters in South America. See the distribution map at Birdlife International.