469 SHORT COMMUNICATIONS ORNITOLOGIA NEOTROPICAL 18: 469–476, 2007 © The Neotropical Ornithological Society A DESCRIPTION OF A NEST AND NESTLINGS OF THE RUFOUS- THIGHED KITE (HARPAGUS DIODON), WITH ADDITIONAL COMMENTS ON DIET AND BEHAVIOR Gustavo Sebastián Cabanne 1 & Ignacio Roesler 2 1 Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, 05508-090, São Paulo, SP, Brazil. E-mail: gscabanne@yahoo.com 2 Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Buenos Aires, Argentina. Descripción de un nido, de pichones y de aspectos de la dieta y comportamiento del Milano de Corbata (Harpagus diodon). Key words: Harpagus diodon, Rufous-thighed Kite, Atlantic forest, Tropidacris, Itatiaia National Park, Juréia Ecological Station, Chapada Diamantina. INTRODUCTION The Rufous-thighed Kite (Harpagus diodon, Accipitridae) is a small raptor that inhabits primary and secondary rainforests in eastern and central South America (Thiollay 1994). It also occupies agro-ecosystems, but usually only those associated with native forest patches (Cabanne unpubl.). Even though the Rufous-thighed Kite is abundant in some regions (Anjos et al. 1997, Cabanne 2005), basic aspects of its breeding biology are totally unknown (Bierregaard 1995, 1998). Only one nest has been briefly mentioned (Wolfe 1938, Brown & Amadon 1968), nestlings and many aspects of behavior are unknown, and the breeding season is merely speculated (Cabanne 2005, Azevedo et al. 2007). The Rufous-thighed Kite is thought to prey mostly on insects and lizards, but its diet is also poorly known (Thiollay 1994, Bierregaard 1998, Ferguson-Lees & Christie 2001). Here we describe a nest and the nestlings of the Rufous-thighed Kite and report original observations on the kite’s diet and general aspects of its reproductive biology. METHODS Study area. Table 1 presents the locations of studied breeding attempts. Nesting sites were in continuous Atlantic forest (Galindo-Leal & Câmara 2003), except in Guaraú. Lençois is in the eastern slope of the Chapada Diamantina region at the northern limit of the hilly range Serra do Espinhaço. The climate at Lençois is tropical and seasonal, with a rainy season from March to June (1000–1300 mm/year). Itatiaia National Park is in the northern hilly