The breeding range of the Black Phoebe (Sayornis nigricans) has recently expanded into Colorado. Since the first state record in 1972, this species has become a regular visitor, ultimately establishing a satellite breeding population in southwest Colorado. In 1998, observers surveying while floating down the San Miguel River, Montrose County, detected 28 Black Phoebes as well as several nests. Since then, Rocky Mountain Bird Observatory (RMBO) staff has monitored the occurrence of Black Phoebe in Colorado. By 2002, through which this paper presents information, the Colorado population of the Black Phoebe, centered along the San Miguel River, numbered probably over 30 pairs.