This study represents the first systematic and permanent bird research conducted in Sierra de Picachos, Nuevo Leon, Mexico. It was carried out from September 1997 to May 2000. There were 39 families, 101 genera with a grand total of 146 species recorded. The ecological distributions of the species by community were: pine (Pinus) forest 23 species; oak (Quercus) forest 50 species; shrubland and ponds 135 species. The species seasonal distributions were: 136 in spring, 39 in summer, 36 in fall, and 83 in winter. All the guild groups were well represented. There were 14 species identified as protected by Mexican law.