Species: Coccyzus americanus occidentalis

F - 20,000-200,000 square km (about 8000-80,000 square miles) - F - USFWS (2001) defined the Distinct Population Segment (DPS) of yellow-billed cuckoo in the western United States as including populations west of the crest of the Rocky Mountains. For the northern tier of Rocky Mountain States (Montana, Wyoming, northern and central Colorado), the crest coincides with the Continental Divide. In southern Colorado and New Mexico the crest coincides with the eastern boundary of the Rio Grande drainage, including the Sangre de Cristo Mountains and excluding the drainage of the Pecos River. In west Texas the DPS boundary is the line of mountain ranges that form a southeastern<br>extension of the Rocky Mountains to the Big Bend area of west Texas, and which form the western boundary of the Pecos River drainage.<br><br>Western populations of the yellow-billed cuckoo currently nest in scattered, isolated areas west of the Rocky Mountains, in California, Arizona, New Mexico, extreme western Texas (subspecies there is uncertain; see USFWS 2001), Sonora, Chihuahua, and south irregularly to southern Baja California and Zacatecas, Mexico (Howell and Webb 1995, Russell and Monson 1998, Hughes 1999), with irregular and/or highly localized nesting in Nevada (USFWS 2001), Utah (J. Parrish, pers. comm., cited by Johnson et al. 2008; Johnson and O'Brien 1998), western Colorado (Kingery 1998, USFWS 2001), and possibly Wyoming, Montana, and southwestern Idaho (USFWS 2001). Localized nesting formerly occurred north to Oregon, Washington, and British Columbia (Hughes 1999), and rare nesting might still occur in Oregon (USFWS 2001). The wintering area for this subspecies has not yet been located (Laymon and Halterman 1987b), but probably it is in South America, possibly to northern Argentina (AOU 1957, 1998).<br><br>Range extent is difficult to estimate but for the breeding range, excluding areas with obviouslty unsuitable habitat, it appears to exceed 20,000 square kilometers.