Between 2008 and 2010, I conducted an inventory of birds in the municipality of Nanacamilpa, Tlaxcala. One hundred twenty-nine bird species were recorded by visual and hearing observations, as well as through catches and photographic records. Information for each species includes information on seasonal status, endemism, conservation status, and habitats used. Fourteen records are noteworthy because they expand the geographical distribution, representing additions to the Tlaxcala avifauna. Coniferous forest showed the highest species richness (68), and the highest species richness and diversity values in the dry (44 species, H'= 3.22 E'= 0.97, λ= 0.049) and rainy (32 species, H'= 3.10, E= 0.93, λ= 0.040) seasons as well. No significant differences were found between of species richness and diversity values between seasons (P> 0.05). Only significant differences were found between coniferous forest and crops, urban and suburban areas, zacatonal with remnant forest and grazing/pasture (P< 0.05). Coniferous forest in Nanacamilpa should be considered a priority area for the conservation of birds, especially of endemic and listed at risk species, as it is one of the habitats being subject to strong anthropogenic pressure.
