Several of the first avifaunal surveys in Colombia were conducted in the lowland moist forests of the Middle Magdalena Valley, but for decades this region has been understudied. We present results of an avifaunal survey in a zone of Cantagallo, Bolívar, Colombia (Jun–Jul 2019), based on the collection of voucher specimens, associated tissue samples, and observational records. We report 165 species, 77 of which are represented with 266 voucher specimens. We found that the nearest documented records for 7 species are more than 100 km away. Moreover, our collection bridges more significant gaps in temporal sampling (mean = 71 year before our survey). Our field work resulted in the first tissue samples for 10 species in Colombia and 64 species from the department of Bolívar. The Middle Magdalena Valley's forests have almost vanished and the surveyed zone should be considered for protection.