DISTINCT SUMMER BIRD ASSEMBLAGES IN TWO FRAGMENTS OF POLYLEPIS FORESTS IN THE SOUTHERN YUNGAS OF ARGENTINA

L. BELLIS; L. RIVERA; M. LANDI; N. POLITI

ORNITOLOGIA NEOTROPICAL

NEOTROPICAL ORNITHOLOGICAL SOC

Lugar: ALEMANIA; Año: 2013

1075-4377

Polylepis forests are considered one of the most threatened Neotropical ecosystems. The tropical Andes avifauna of Polylepis forests has been relatively well studied in Bolivia and Peru; however, in Argentina this information is scarce. In this study we characterize and compare bird assemblages in two humid Polylepis forests fragments of the Southern Yungas; P. australis and P. hieronymi, and provide the first exhaustive bird list for P. hieronymi forest. Fieldwork was carried-out in two mountain ranges in Jujuy Province with Polylepis forest dominated by the different species. We recorded a total of 391 birds belonging to 43 species. Bird richness, relative abundance, and diversity were higher in P. australis than in P. hieronymi forest. There was a high turnover in species composition between communities (Sørensen similarity index= 23%). Indicator species of each forest type were Rufous-collared Sparrow (Zonotrichia capensis, IV = 90%) in P. australis and White-crested Elaenia (Elaenia albiceps; IV = 70%) in P. hieronymi forest. Habitat use guilds showed a significantly higher bird abundance of generalist and forest edge or open areas in P. australis than in P. hieronymi forest, but there was no difference between abundance of forest bird species. The absence of bird species highly associated with Polylepis forests could be related to the retraction of current Polylepis forests and to their structural simplification caused by anthropogenic disturbances. Therefore, the boundaries of Calilegua National Park should be broadened to include P. australis and of Las Lancitas Provincial Reserve to include P. hieronymi to ensure the conservation of Polylepis forest bird assemblages.