Uso e seleção de recursos por Harpia em múltiplas escalas espaciais: persistência e vulnerabilidade.

Abstract

Studies of the effects of deforestation and forest fragmentation on species and ecological processes have provided important background to biodiversity conservation. The Harpy Eagle (Harpy harpyja), the most powerful bird of prey, with a long lifespan, and high nest-site fidelity, returns to a same nesting-tree for decades. Its long-term use of nest sites and use of surrounding resources means that the resistant of the species depends on its capacity to adjust to changing resources. This thesis describes aspects of Harpy Eagle ecology revealed by remote monitoring techniques, such as satellite images, individual movements recorded by satellite radio-transmitters and photos from camera trapping. In Chapter I, the dynamics of landscapes surrounding Harpy Eagle breeding sites were quantified at multi-scales from satellite images. Most nests located along the roads were surrounded by a heterogeneous matrix with anthropogenic uses, such as agriculture and pasture. In the region of the 'Deforestation Arc', the remaining habitat is functionally disconnected for dispersion of Harpy Eagles juveniles. However, the functional diversity of prey species consumed by Harpies indicated that deforestation may reduce the availability of food resources. Although protected areas have contributed to the maintenance of breeding sites of Harpy Eagles in the Atlantic Forest, the Amazon probably will be the last refuge of this species, with negative implications for a long-term viable Harpy Eagle population. These results indicate the priority areas for which management and conservation actions should be directed: Atlantic Forest, along the BR163 and BR230 highways, and eastern and southwestern Amazonia. In Chapter II, locations from satellite telemetry were used to quantify the home range of three Harpy Eagles in different situations of conservation threat in the Amazon, identifying behavioral modifications and displacement patterns in fragmented landscapes. In Chapter III, images from camera traps installed near Harpy Eagle nests in the Amazon and Cerrado forests reveal ecological intra- and interspecific interactions related to nest height, and predation risk while at the nest. In Chapter IV, the availability of prey species data sampled by standard methods (RAPELD method), allowed the comparison of resource availability and its use by Harpy Eagles in breeding sites near the Xingu River in the Brazilian Amazon.