451 SHORT COMMUNICATIONS ORNITOLOGIA NEOTROPICAL 19: 451–456, 2008 © The Neotropical Ornithological Society INCUBATION BEHAVIOR OF THE WHITE-BROWED SPINETAIL (HELLMAYREA GULARIS) IN SOUTHEASTERN ECUADOR Harold F. Greeney 1 & Kristof Zyskowski 2 1 Yanayacu Biological Station and Center for Creative Studies, c/o Foch 721 y Amazonas, Quito, Ecuador. E-mail: revmmoss@yahoo.com 2 Yale University, Peabody Museum of Natural History, 170 Whitney Avenue, New Haven, Connecticut 06520, USA. E-mail: kristof.zyskowski@yale.edu Comportamiento de incubación del Colaespina Cejiblanca (Hellmayrea gularis) en el sureste del Ecuador. Key words: Furnariidae, nest, egg, water loss, behavior, cloud forest, Andes, Hellmayrea gularis, White- browed Spinetail. The White-browed Spinetail (Hellmayrea gularis) is a wren-like furnariid representing a monotypic genus. It inhabits the wet under- growth of Andean forests from western Ven- ezuela south to central Peru, being encountered most frequently in Chusquea bamboo thickets and stunted elfin forest near the treeline. Although habitat-specific, the species is fairly common through most of its range and not globally threatened (Hilty & Brown 1986, Fjeldså & Krabbe 1990, Anony- mous 2000, Ridgely & Greenfield 2001, Rem- sen 2003). Despite being found across a large latititu- dinal range, the White-browed Spinetail remains poorly studied. The details of nest architecture, a large mossy ball opening later- ally, have only recently been described (Greeney & Zyskowski in review), and there is no published information on its breeding behavior. Here we present a description of the eggs, nestlings, and incubation behavior of the White-browed Spinetail from south- eastern Ecuador. We made observations on the breeding of the nominate subspecies of the White-browed Spinetail in October and November of 2004 at the Tapichalaca Biological Reserve (04º 30’S, 79º10’W), located on the east slope of the Andes, c. 11 km north of Valladolid in the southeastern Zamora-Chinchipe Province of Ecuador, at altitudes of 2550–2650 m. The habitat in this area is steeply sloped evergreen forest, with a 15–20 m canopy and an under- story dominated by tree ferns (Cyathaceae) and Chusquea bamboo (Poaceae) (Krabbe et al. 1999). Additionally, Paul Martin found a fourth nest under construction in the vicinity of the town of Papallacta (00°36’44”S, 78°15’12”W), Napo Province, at an altitude of 3340 m. Below, we include egg measure- ments from this nest.