The bird collection at San Carlos University (USAC) is part of the Biological Collections System administrated by the School of Biology, Facultad de Ciencias Químicas y Farmacia. The collection is made up of approximately 1,600 specimens. Species from different regions of Guatemala are represented, with greater emphasis on species from mountain ecosystems. The specimens are prepared as study skins, although a small number of specimens are preserved in liquid. The bird collection also has tissue samples for molecular studies, all of them preserved in 95% ethyl alcohol.