Nesting Biology of the Yellow-Olive Flatbill (Tyrannidae, Elaninae) in Atlantic Forest Fragments in Brazil

Abstract

Abstract The Yellow-olive Flatbill (Tolmomyias sulphurescens) is a small insectivorous passerine inhabiting Neotropic forests. Its breeding biology is poorly known despite its abundance and conspicuousness. We describe the nesting biology of Yellow-olive Flatbills from Atlantic Forest fragments in Belo Horizonte County, Minas Gerais State, southeastern Brazil. Eighty nests were monitored every 3–5 days from August to January between 1995 and 2000. Active nests were found from mid-September through late December with a peak from mid October through late November. First clutches were usually laid during the first rains, but prior to the main peak in annual rainfall. The Yellow-olive Flatbill builds closed, pencile nests on tree branches along streams or roads, principally of dark fungal (Marasmius sp.) fibers. Clutch size ranged from two to four white eggs. Incubation was irregular and hatching was asynchronous. Incubation and nestling periods were 20 and 23 days, respectively. Nesting success across all 5 ...