Aves do estado do Amazonas, Brasil: diversidade e padrões de distribuição

Abstract

The Amazon is one of the most biodiverse regions in the world, and it still has many open questions about how many birds occur in this biome or where many occur. Due to its vast extent, it is necessary to subdivide this region to begin investigating species richness and distribution patterns. The state of Amazonas, in Brazil, represents a large part of the heterogeneity of this biome. In addition, the use of a geopolitical unit is the basis for public policies for biodiversity conservation. In this dissertation, we use the state of Amazonas to investigate species richness and distribution patterns in Amazonian birds. In the first chapter, we elaborated the first documented and annotated checklist of birds for the state of Amazonas. We found that the state is home to 1,085 bird species, including: 51 endangered, 47 endemic to Brazil, and five endemic to the state. This state is home to more than half of Brazil’s avifauna, and is the division within a country with the highest bird richness in the world. In the second chapter, we expand the checklist of the state of Amazonas including subspecies, and analyze the distributions of taxa within the proposed areas of endemism based on the description of distributions in the literature, to detect incongruent distribution patterns with those already proposed and with the purpose of stimulating new questions about these areas. The use of subspecies and monotypic species proved to be effective in detecting discrepant distribution patterns in areas of endemism, such as taxa from mountains, floodplains, mini-interfluves, and that occur in the upper and lower parts of the interfluves, without detectable geographical barrier. Many taxa with similar distributions suggest that the upper Negro-Amazon interfluve and headwaters of the Amazon-Madeira tributaries should be reassessed as areas of endemism. In the third chapter, the previous analysis allowed us to discover a new bird species record for Brazil (Chiroxiphia napensis). The presence of C. napensis in the Brazilian territory can be used as a model when evaluating distributions of species with few records and that seems to be delimited by large rivers.