Density and spatial distribution of the Caatinga endemic White-browed Guan (Penelope jacucaca) in northeastern Brazil

Understanding ecological aspects of threatened populations is one of the fundamental steps for a correct management. Information concerning geographic distribution and population size are the most important criteria for the definition of threat categories, which in turn guide the investment of resources in conservation programs. The White-browed Guan (Penelope jacucaca) is a Caatinga endemic species classified as vulnerable at national and global level. Little is known about its ecological aspects, and demographic data are practically nonexistent. These gaps constitute a major challenge for effective conservation measures. We analyzed the spatial distribution and population density of the White-browed Guan along a 130km corridor between the states of Ceará (CE) and Paraíba (PB) during three years (2014-16). The study area presents a heterogeneous soil cover, with predominance of crops and pastures, interspersed by small patches of native vegetation. Linear transections were applied at 22 sampling areas, with an effort of 370 km traveled and 246 observation hours. We recorded 219 individuals in 45 records. The species occurred in higher density in the areas with greater forest cover, dominated by the arboreal and shrub caatinga. The Catolé (CE) and Serra de Santa Catarina (PB) regions concentrated 80% of the records and represent the most important areas for the species along the corridor. These areas represent the last relatively preserved forest refuges in the study area. Hunting and deforestation are the main deleterious factors for this species in the region.