Structure and composition of avifauna in two forest areas in Western Amazonia

Abstract

The Amazon region boasts one of the world's greatest diversities of bird species and the highest in Brazil. However, overexploitation and habitat destruction have affected all animal species, particularly birds. Forest fragmentation leads to habitat reduction, species impoverishment, and alters the composition of the avifauna community. Therefore, it is crucial to understand the arrangement of bird communities in these areas to guide conservation efforts. This study aimed to describe and compare the structure of bird communities in two forest fragments of different sizes and proximity to urban areas in the municipality of Cruzeiro do Sul, Acre. Using MacKinnon's list methodology, bird communities were sampled in two areas, recording a total of 189 species. The larger rural area, with lower anthropogenic influence, exhibited higher species richness (n=148), with groups more specialized in terms of habitat and diet and sensitive to environmental changes, indicating greater species diversity. In contrast, the smaller urban area had fewer species (n=77), mostly belonging to generalist groups. The data revealed differences in bird communities between the locations, with the larger fragment less affected by human presence showing greater species diversity and hosting more species sensitive to environmental changes and dietary specialists.