Tropical dry forest's birds in Tolima Department (Colombia): community analysis

The tropical dry forest life zone in the Upper Magdalena Valley (Tolima, Cundinamarca, and Huila regions) does not have a detailed record or information about bird assemblages, thus making it necessary to study this topic in the region. Therefore, our goal was to study the tropical dry forest's bird assemblage in 37 localities in Tolima (Colombia) through published articles, technical documents, and experts' unpublished lists. We registered 297 bird species; the bird registration index was considered as an independent variable, thus allowing us to make comparisons among localities with different sampling efforts. San Pablo and Corinto localities had high Bird registration index values, being important conservation areas. The locality with the highest number of species (162) was "Laguna El Toro", possibly because of a higher number of studies in that area. The species associated to ecological categories II (wide-tolerance birds) and III (open-areas birds) registered the highest number of species (126 and 91 respectively); whereas the ecological category I (forest-specialist birds) only registered 35 species. According to rarefaction's curve and Clench's model we estimated about 92-93% of expected species for the region (ca. 322). We found that the high number of species in tropical dry forest of Tolima is associated with the ecological categories II and III; and it would be related to vegetal heterogeneity and landscape units in this region. Additionally, the number of species in our study is higher than that registered for the Colombian north coast and some countries such as Nicaragua, Costa Rica, and Mexico located in the same life zone.