versión ISSN 0717-6538
GONZALEZ, Angélica L; VUKASOVIC, Μ. Angélica y ESTADES, Cristian F. Temporal variability in the abundance and diversity of aquatic birds in the Itata River wetland, Bio-Bio Region, Chile. Gayana (Concepc.) [online]. 2011, vol.75, n.2, pp. 170-181. ISSN 0717-6538. doi: 10.4067/S0717-65382011000200006.
Coastal wetlands play an important role as habitats for visitant and resident aquatic bird species. Although, their relatively high bird diversity, in Chile very little is known about bird community structure and their dynamics in these wetlands. To investigate the importance of the Itata river wetland (Chile) for waterbirds, we conducted seasonal censuses over five years between 2006 and 2010 within this wetland. We evaluated temporal patterns in waterbird diversity and we used the indicator species analysis (Indval) to identify bird species as bioindicators of the temporal community structure in this ecosystem. We recorded 71 bird species, which represents a 54% of the national waterbird species. Most of these species (77%) are classified as resident species, whereas the 20% are visitors, and the 3% sporadic. A high number of shorebird species use this wetland as stopover site during austral summer. Our results revealed that significant temporal differences in waterbird community structure exist along the five-year period in the Itata River. Cluster analysis classified the waterbird community into four significant clusters, and each cluster showed seasonal patterns characterized by a variable number of indicator species. The abundance of both, the most numerically dominant and frequent bird species, such as Vanellus chilensis, Himantopus melanurus, Charadrius modestus and Sterna hirundinacea explained much of this temporal variation. Different ecological factors might influence the temporal patterns of the bird community structure in the Itata River, and should be addressed in future studies of this wetland. Moreover, this high local pool of species might be important in maintaining the landscape diversity, through movements across other local or regional wetlands.
Palabras clave : Indicator species analysis; Migratory birds; Shorebirds; Wetland.