Аннотация:Mar Chiquita is a large inland brackish water body of about 2,000 km2, with a salinity of around 100 °/oo. Its aquatic bird communities were studied throughout a year in three study areas, representative of the main habitat types found in the región. We collected information on species composition and abundance, as well as foraging behaviour, feeding site utilization and stomach contents.
In total we recorded 55 species. The richest community (both in number o f species and individuals) was found around the Rio Segundo estuary, while the less diverse corresponde to saline ponds near the coast. Summer migrant species (long range neartic migrants) included nine species and accounted for the 21% of the observed birds. Winter visitors included five species and made up 1% of bird numbers. Ecological guilds species composition and patterns of resource utilization are analyzed. They closely resemble those of marine estuarine and intertidal conditions. At present, the main adverse factors for the preservation of the local aviiauna are linked with planned stream regime modifications through dam building, and contamination due to industrialdevelopment along tributary rivers.
