In the sixth edition of the American Ornithologists’ Union’s Check-list of North American Birds (1983), Clark’s Nutcracker (Nucifraga columbiana) is described as occurring only as a nonbreeding wanderer in mainland Mexico. The only locality in the Sierra Madre Oriental where the species has been reported is Cerro El Potosí, which lies 25 km northwest of Galeana, in central western Nuevo León. Nutcrackers were first reported at this locality by Leopold (1947), who collected one of three birds seen on 16 July 1945. Later, Allan R. Phillips (pers. comm.) saw two individuals there on 18 May and four on 19 May 1975, respectively. Andres M. Sada (pers. comm.) observed three individuals there on both 5 February 1983 and 12 October 1986. I saw four on 15 November and nine on 16 November 1985, when one adult, probably a female, was collected (Universidad Autónoma de Nuevo León catalog number 1678). Most recently, I saw twelve nutcrackers on 20 June and five on 10 July 1991, at elevations above 3500 meters above sea level; one of these birds was feeding on cones of Pinus ayacahuite.