Avifaunal Surveys of the Upper Apurímac River Valley, Ayacucho and Cuzco Departments, Peru: New Distributional Records and Biogeographic, Taxonomic, and Conservation Implications

Abstract

ABSTRACT The sliver of humid tropical and montane forest on the east slope of the Andes in Ayacucho Department ranks among the least surveyed sectors of the Peruvian Andes. This mountainous region, along with adjacent Apurimac Department and western Cuzco Department, comprise the Apurimac River Valley, a putative biogeographic barrier. Hence, understanding avian distributions in the vicinity of the Apurimac River Valley is fundamental to understanding faunal turnover across it. Here, we report results of recent avifaunal surveys (2008–2012) from five sites in the Apurimac Valley region. We report 35 bird species previously undocumented in Ayacucho, six of which represent range extensions, including records of the endemic Black-spectacled Brush-Finch (Atlapetes melanopsis), Marcapata Spinetail (Cranioleuca marcapatae), and Chestnut-breasted Mountain-Finch (Poospiza caesar); the remaining records filled perceived range gaps. Specimen evidence suggests little phenotypic introgression between differentiated f...