Padrões de uso de habitat e o efeito do alagamento permanente sobre a avifauna de várzea afetada pela UHE Santo Antônio no Rio Madeira

Abstract

Floodplains are highly productive environments with a rich diversity of species adapted to seasonal changes in the landscape, resulting from flood pulses. It is estimated that 15% of bird species in the Amazon are associated with floodplains. Historically, however, floodplains have always been less studied than upland forests (terra firme) and currently suffer from different types of impacts, such as the planning and implementation of hydroelectric plants in several hydrographic basins in the Amazon. The growing pressure these environments face contrasts with the lack of knowledge about some aspects of their avifauna. This thesis, organized in two chapters, investigated the impacts of the Santo Antonio hydroelectric power plant on the varzea associated avifauna, and the occupation patterns of floodplain bird species along the Madeira River in the municipality of Porto Velho, State of Rondônia, Brazil. The first chapter describes how the floodplain bird community responded to flooding due to the filling of the Santo Antônio hydroelectric plant reservoir. The second chapter deals with the relationship between environmental variables that are considered important for the occurrence of birds in the floodplain and the patterns of occupation and detectability of the response of these species to the flood pulse. The results show which groups of birds are potentially more threatened by the impact caused by hydroelectric plants and present new information that contributes to understanding the ecology of some floodplain species.