The Buff-collared Nightjar, also known as Ridgway's Whip-poor-will or Cookacheea, is a Mexican and Central American species that occurs only sparingly within the United States, primarily in southeastern Arizona and southwestern New Mexico. Although this species was first collected in 1894 from Guerrero, Mexico, by E. W. Nelson ( Nelson 1897a ), its history in the United States began in 1958 with the collection of the first specimens in Guadalupe Canyon, NM. Two years later it was collected in Guadalupe Canyon, AZ, and it has been found in Arizona in most years since 1976. This species has been found at fewer than 20 locations within the United States. Its known range in Arizona extends a mere 171 km north of the border.
Because of its nocturnal habits and limited distribution in the United States, the “Buffjar,” as this bird is known colloquially, is a difficult species to see or study there. In recent years, a short stretch of McCleary Wash (usually referred to as Florida Wash by birders) below Madera Canyon in the Santa Rita Mountains of southeastern Arizona has been the mecca for birders seeking this species in the United States. Other than at this one heavily visited location, encounters with Buff-collared Nightjars in the United States are very infrequent.
There is little information about this species and it is difficult to determine to what extent, if any, the status of this bird in the United States has changed. Because its distinctive voice is much different from that of other North American nightjars, it seems unlikely that ornithologists could miss this species. However, many of the areas known to support it in recent years are quite remote, unlikely to be visited frequently by ornithologists at the correct time of day. Even today, the Buff-collared Nightjar's penchant for inhabiting remote desert canyons certainly makes it hard to find by all but the most dedicated observer.
Information on this species outside the United States is almost nonexistent. Other than at locations where the species has been seen or collected and a few nests found (and these have not been studied in detail), the Buff-collared Nightjar awaits study.