Bird community structure and dynamics in the campos rupestres of southern Espinhaço Range, Brazil: Diversity, phenology and conservation

Abstract

"Campos rupestres" comprises the open vegetation growing above 900 m altitude mainly along the Espinhaço Range, eastern Brazil. We presents the first thorough assessment concerning the bird community structure and dynamics in campos rupestres of southern Espinhaço, in the western slope of Serra do Cipó. We investigated the species richness, composition, abundance, seasonality, and conservation. From 2005 to 2007 we performed visual and acoustic detections and mist-netting. Every species was categorized according to two types of classification schemes that reflect its pattern of occurrence and seasonality: Frequency of Occurrence (FO) and Phenological Category of presence (PC). We recorded 81 species, including endemics, endangered, and new records. The 287 mist-netted individuals showed a multi-modal abundance distribution among species, suggesting that the community has few common and many rare species. The most abundant species was a campos rupestres endemic hummingbird, the Hyacinth Visorbearer Augastes scutatus. The same pattern was verified for the FO, with few "Common" (5%) and many "Occasional" (27%) species. Regarding the PC, almost half of the species were categorized as "Residents" (47%), 14% as "Migratory", and 31% as "Occasional visitors". The annual occurrence pattern of the seasonal species differ by "Occasional visitors" being more narrowly concentrated than "Migratory" species. We discuss the occurrence and phenology patterns of species and some threats to the campos rupestres. Although relatively poor in species richness, the Cipó campos rupestres avifauna has a distinct composition, and we suggest that the patterns found here reflect a general dynamic for the campos rupestres habitat as a whole. Our results may be useful in further investigations concerning the existence of distinct ecosystems within "campos rupestres" complex, and may also provide a baseline for future assessments of the conservation status of those threatened ecosystems.