Greeney et al. 10 Boletín SAO Vol. 18 Tangara heinei nesting biology (No. 1) – Pag: 10-15 Boletín SAO | http://www.sao.org.co/publicaciones/boletinsao/Boletin%20sao.htm | Mayo 2008 | Protegido por – Protected by Creative commons Colombia| Notes on the nest architecture and nesting biology of Black-capped Tanager (Tangara heinei) in northeastern Ecuador Harold F. Greeney A , Benjamin Freeman A , Kimberly S. Sheldon A,B , Robert C. Dobbs A & Rudolphe A. Gelis A,C A Yanayacu Biological Station & Center for Creative Studies, Cosanga, Napo, Ecuador. c/o Foch 721 y Amazonas, Quito, Ecuador. E-mail: revmmoss@yahoo.com B Department of Biology, University of Washington, Box 351800, 24 Kincaid Hall, Seattle, Washington 98195-1800, USA. C Pasaje Manuel García y 18 de Septiembre N20-28, Quito, Ecuador. Abstract Several brief accounts of the nesting biology of the Black-capped Tanager (Tangara heinei) have been published, most of them from Ecuador. Despite this, little is known of the specifics of nesting biology and nest architecture. Here we describe building behavior, nesting seasonality, and the details of nest architecture of the Black-capped Tanager in eastern Ecuador. Key words: Black-capped Tanager, eggs, nest architecture, nest components, nest placement, Tangara heinei, waterloss. Resumen Existen varias descripciones de la biología de anidación del Tangara Gorrinegra (Tangara heinei ), la mayoría provenientes de Ecuador. Aún así, no conocemos mucho sobre los detalles del comportamiento de adultos o la arquitectura de los nidos. Aquí describimos el comportamiento de los adultos durante la construcción, patrones estacionales de anidación, y los detalles de la arquitectura del nido de la Tangara Gorrinegra en el este de Ecuador. Palabras clave: arquitectura del nido, componentes del nido, huevos, Tangara Gorrinegra, Tangara heinei, ubicación de nidos, perdida de agua de huevos. he Black-capped Tanager (Tangara heinei ) is a monotypic species distributed from Venezuela to northern Ecuador (Isler & Isler 1999). It inhabits elevations from 1000 to 2700 m, and is frequently associated with forest disturbance, including natural forest openings and human-disturbed second growth (Hilty & Brown 1986, Isler & Isler 1999, Ridgely & Greenfield 2001). Despite being fairly common and widespread, little is known of its breeding biology. Hilty and Brown (1986) described a “grassy cup decorated with moss” from Colombia, and eggs from Colombia were described as pale greenish-white or dull blue with brown, grey, and lilac markings (Sclater & Salvin 1879, Ogilvie-Grant 1912, Hilty & Brown 1986). Ewert (1975) observed a pair during nest building and noted that, while only the female brought material, “both sexes participated in forming the nest”. More recently, several authors have described nests and eggs from western Ecuador (Greeney & Nunnery 2006, Arcos-Torres & Solano-Ugalde 2007). Here we present observations from north-eastern Ecuador on nest architecture, behavior during nest construction, and egg morphology. We made all observations at Yanayacu Biological Station and Center for Creative Studies (00°36 S, 77°53 W, 2100 m), located 5 km west of Cosanga, adjacent to Cabañas San Isidro, Napo Province, Ecuador. Behavior during nest construction. Using a video camera placed 10 m from the nest, we recorded adult behavior for the three days prior to laying of the first egg. At the time we began filming, the basic nest-cup structure was fairly well formed, but still weak and thin- walled. We recorded behaviors at the nest from 05:45 h to 18:15 h daily, for three full days. In general, during the observation period, which began initial formation of the cup, there was one behavior which the female used repeatedly to shape the cup. She would press her belly and breast down into the cup, with her rump slightly elevated and her wings slightly raised upward and backward so that the tips met across her rump. Once in this position, she would vibrate her entire body, stand and rotate slightly, then repeat the vibration. Often she would grab bits of stray material from the rim and tuck them under her breast before repeating the vibration. We T