Aves Aquáticas do Reservatório da Hidrelétrica de Tucuruí: Bases para a Gestão das Áreas Protegidas da Maior Barragem da Amazônia

Abstract

Waterbirds of the Tucuruí Hydroelectric Reservoir: Basis for the Management of Protected Areas of the Largest Dam in the Amazon. This study analyzes the waterbird community of the Tucuruí Hydroelectric Reservoir, Pará, Brazil, a mega-dam that dammed the Tocantins River in 1984 and surrounded by the Tucuruí Lake Conservation Unit Mosaic. Our objective was to describe the diversity and species composition, as well as to identify temporal and spatial distribution similarity patterns . We used linear transect sampling in two periods: between 2005 and 2007, 21-23 years after the damming, and in 2024, 40 years after the damming. We recorded 47 species of strictly aquatic non-passerine birds distributed in 21 families. The most abundant species were Butorides striata, Cairina moschata and Ardea cocoi. Surface-dwelling piscivorous birds represented the dominant ecological guild. Species accumulation curves indicated adequate sampling effort, although with greater uncertainty for 2024. The analysis revealed significant seasonal variations between dry and flood seasons. Significant temporal variations in total abundance were observed between 2006 and 2007 compared to 2005 and 2024. However, richness and diversity remained relatively stable between years and types of conservation units (APA, RDS, ZPVS). Using non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM), significant differences in species composition were identified between seasons and years, but not between types of conservation units. These results underscore the importance of the Tucuruí Lake Conservation Unit Mosaic as an ecological refuge for aquatic and migratory birds, highlighting the need for ecological restoration of the Permanent Protection Areas (APPs) on the banks of the Tucuruí HPP reservoir.