Remnant Avian Megafauna in South America: An Evaluation of the Occurrence of Breeding Greater Rheas (Rhea americana) in NonProtected Landscapes in the Brazilian Cerrado

Abstract

Concern for megafauna conservation has increased in the last decades. The Greater Rhea Rhea americana is the largest bird species inhabiting South America. It is considered Near Threatened, mainly due to habitat loss, and hunting. Although it occurs through an extensive geographic distribution, most detailed investigations have been conducted in Argentina. This study was aimed at examining breeding aspects of Greater Rheas in non-protected landscapes in the Brazilian Cerrado. Records of this species with evidence of breeding activities (nests, eggs, young) were obtained through searches for photographs in the WikiAves database. A total of 104 breeding records were obtained by citizens. These records were concentrated in central and western Cerrado. Most municipalities with breeding records have less than 30,000 habitants, and human population densities lower than 10 individuals/km2 . The breeding season occurs between June and March-April. Results indicate that breeding Greater Rheas use a range of modified habitats in non-protected landscapes, and their occurrence in the Cerrado is strongly associated with municipalities with low human abundance.