Coastal waterbirds of El Chorro and Majahuas, Jalisco, México, during the non-breeding season, 1995-1996

We studied how waterbirds used two small estuaries during the non-breeding season of 1995-1996. These estuaries, El Chorro and Majahuas, were located in the middle of a large span of non-wetland habitat along the Pacific coast of México. Whereas El Chorro was basically a large and open waterbody, Ma...

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Bibliographic Details
Main Authors: Salvador Hernández-Vázquez, Eric Mellink
Format: Article in Journal/Newspaper
Language:English
Spanish
Published: Vicerractoría Investigación 2001
Subjects:
Online Access:https://doaj.org/article/7c70232d0daa498089972c8702a66626
Description
Summary:We studied how waterbirds used two small estuaries during the non-breeding season of 1995-1996. These estuaries, El Chorro and Majahuas, were located in the middle of a large span of non-wetland habitat along the Pacific coast of México. Whereas El Chorro was basically a large and open waterbody, Majahuas was a long and narrow corridor flanked by mangroves. The two estuaries had 77 species throughout our study, but shared only 58, due to differences in their habitat. Seabirds comprised 66% of all the birds; grebes, ducks and rails 16%; shorebirds 12% and herons and egrets 5%. During late winter and early spring a very reduced number of migratory species accounted for the dominance of seabirds. Sterna hirundo and Phalacrocorax brasilianus accounted for 40 and 33%, respectively, of all the seabirds. Opening or closure of the estuary mouth at El Chorro affected the bird communities at both sites, by exposing or inundating a large mudflat in that estuary. Overall, however, time of the year was more important in the composition of the bird assemblages. Both estuaries should be considered as a single unit. Durante la estación no reproductiva de 1995-1996 estudiamos las aves acuáticas de los estuarios El Chorro y Majahuas, Jalisco, México. El Chorro es un cuerpo de agua más abierto, mientras que Majahuas está formado por canales rodeados por manglares. Registramos 77 especies de aves. Las aves marinas comprendieron el 66%, los patos y similares el 16%, las aves playeras el 12% y las garzas el 5%. Sterna hirundo y Phalacrocorax brasilianus representaron el 40 y 33%, respectivamente, del total de aves marinas. El que la bocabarra de El Chorro estuviera abierta o cerrada influyó en la concentración de aves en los dos esteros, debido a la exposición o inundación de áreas lodosas y arenosas. A pesar de las diferencias entre los dos estuarios, la época del año fue más importante en la composición de las comunidades de aves. Ambos esteros deben considerarse como una sola entidad ecológica.