Avian community dynamics in a forest patch in the Fazenda Rio Claro, Len?óis Paulista, S?o Paulo, Brazil

摘要

This paper discusses a qualitative and quantitative survey of the avian community in the Fazenda Rio Claro (22°27'S, 48°51'W), Lencois Paulista, Sao Paulo State. The quantitative survey was conducted in the period August 2001-July 2002 using the Point Counts method. Diversity, frequency of occurrence (FO), abundance and evenness were measured for the community, which was classified into food categories and vertical occupancy of plant strata. The qualitative survey recorded 216 species, 82 of which were non-Passeriformes and 134 Passeriformes. The quantitative survey recorded 74 species and 761 contacts, with an average of 12.7 contacts per sample. The Abundance Index (IPA) varied from 0.001 (one contact) to 0.07 (53 contacts); the Diversity Index was H' = 3.10, showing a significant increase between September and November. Evenness averaged 0.95. Insectivores accounted for almost half the total number of species recorded in the quantitative survey (44%), followed by frugivores (24.9%), omnivores (16.4%), carnivores (8.5%), detritivores (1.4%), and a small proportion of nectarivores. Insectivores were the most abundant category in the understory, while frugivores were most abundant in the canopy and on the ground. The bird community of Fazenda Rio Claro is relatively stable, balanced and even in terms of richness, number of species, and IPA. Some endangered species are found in the area.