ABSTRACT
El Paso de Portachuelo es un abra utilizado por una gran diversidad de especies de aves, bien sea como residentes o para movimientos estacionales o migratorios, en el cual se han reportado 32 especies de colibríes en la familia Trochilidae. Debido a esto nos planteamos como objetivo evaluar la dinámica del ensamble de colibríes que usa dicho Paso. Se realizaron salidas de campo mensuales desde abril 1990 hasta noviembre 1994, y desde junio 2010 hasta noviembre 2013. Se capturaron 14 685 individuos, pertenecientes a 38 especies. Las especies con poblaciones que presentaron mayores abundancias fueron: Heliodoxa leadbeateri y Sternoclyta cyanopectus. Con base en los resultados obtenidos, la comunidad de colibríes del área de Portachuelo se puede dividir en: seis especies altamente abundantes y que se observan durante todo o la mayor parte del año, siete especies que utilizan el paso durante la mayor parte del año pero con densidades bajas, cuatro especies que utilizan la zona de manera estacional y siete especies raras en las capturas debido al tipo de muestreo, o a que no presentan movimientos de desplazamiento y prefieren otros hábitats.
Portachuelo Pass is an open area used by a great diversity of bird species, either as residents or for seasonal or migratory movements, reporting 32 species of hummingbirds in the Trochilidae family. Due to this, our goal was evaluating the hummingbird assemblage dynamics in Portachuelo Pass, analyzing the abundance of the captures over four years of sampling and comparing these data with samples taken between 1990 and 2013. Monthly field trips were made from April 1990 to November 1994, and from June 2010 to November 2013, between 5 and 8 mist-nets were used to catch the birds. 14 685 individuals were captured, belonging to 25 species. The relative abundance per species was estimated in each of the sampling months, separating the community into four groups: A) Hummingbirds with high abundances, B) Hummingbirds with low abundances, C) Hummingbirds rare and D) Phaethornithinae. The species with the highest abundance populations were: Heliodoxa leadbeateri and Sternoclyta cyanopectus, followed by Aglaiocercus kingi, Chalybura buffoni, Chrysuronia oenone and Coeligena coeligena. For the rest of the species the densities in the mist-net captures were from low to medium. Based on the results obtained, the community of hummingbirds in the area of Portachuelo can be divided into: six highly abundant species that are observed throughout all or most of the year, seven species that use the passage during most of the year but with low densities, four species that use the area in a seasonal manner and seven rare species in the catches due to the type of sampling, or that do not present displacement movements and prefer other habitats. Statistically significant differences were found between the abundance of hummingbirds of sampling years, being the year with the highest abundance 1991, followed by 2013.