We conducted 14 bird surveys in the Melincueś aline lake from 1992 to 2002 (7 in winter and 7 in summer), and we detected 223,643 individuals belonging to 71 species from 17 families. The more abundant species were Fulica leucoptera, Larus maculipennis, Phoenicopterus chilensis, Plegadis chihi, Anas platalea, Himantopus mexicanus, and Rollandia rolland. Bird abundance was similar in winter and summer, whereas species composition differed between seasons. We recorded 65 species in summer and 59 in winter. P. chilensis and A. sibilatrix were more abundant in winter, whereas Ajaia ajaja, Phalacrocorax olivaceus, Ardea ibis, Sterna nilotica, Egretta thula, Mycteria americana, Charadrius collaris, A. versicolor, Calidris fuscicollis, and Ciconia maguari were more abundant in summer. Bird abundance in each survey was positively associated with the lake level. In summer surveys, the highest variation in species composition through the years was associated with water level fluctuations. Shorebirds predominated in those years with lower level, whereas the species that fed mainly on plants or vertebrates predominated in years with higher levels. Those species that fed on invertebrates (not shorebirds) and those that fed on invertebrates and plants predominated in years with intermediate level. The omnivorous species predominated in years of lower level. There were differences among transects in the proportion of different trophic groups. Short-term studies that do not take into account the particular dynamic of these systems may lead to erroneous generalisations. Thus, the long-term information of this study may be useful for management and conservation of species and system.

We present a waterbird inventory of the Laguna Melincué Ramsar Site in southern Santa Fe province, Argentina. We record 109 species from 28 families of non-passerine birds, including the 14 Nearctic species, four southern austral migrant species, three northern austral migrants, 17 partial migrants, and two altitudinal migrants. The eight most abundant species belong to different families and trophic groups. Thirty-six species were observed nesting or rearing chicks. This baseline knowledge of non-passerine birds will be useful to assist future conservation studies in this highly threatened area.

Durante 1999–2016 se realizaron conteos invernales de Flamenco Austral (Phoenicopterus chilensis) y Parina Grande (Phoenicoparrus andinus) en distintos sectores de la laguna Melincué y se registraron las variaciones en el nivel del agua y su salinidad. Además, se registraron las posiciones de individuos de Parina Grande equipados con transmisores. La cota fluctuó entre 86.1–82.3 msnm. En 2005 se empezó a bombear agua y la conductividad disminuyó marcadamente. La conductividad estuvo asociada positivamente con la abundancia de la Parina Grande y negativamente con la del Flamenco Austral. Los individuos con transmisores estuvieron presentes en julio–septiembre, permaneciendo largos periodos en los mismos sectores. La Parina Grande se concentró en ciertos sectores, mientras que el Flamenco Austral se distribuyó más uniformemente y su abundancia aumentó en los años de cota alta en los sectores este y oeste. La proporción de individuos de ambas especies en el sector sur aumentó al disminuir el nivel de la laguna. Los resultados confirman la importancia de la laguna para la conservación de estas especies.