DIVERSITY AND SEASONALITY OF BIRDS IN PERMANENT WATERHOLES IN THE PERUVIAN NORTHWEST

Abstract

In arid environments, the presence of water sources is key for biological communities as they provide a vital element that is scarce. In this study, we evaluated the diversity and the relative abundance of bird species in seven permanent waterholes, located along an elevational gradient in mountain dry forests in northwestern Peru. From January to December 2016, we analyzed 114,438 photos (22,888 photo events) obtained through camera traps, and counted bird species and individuals photographed at these waterholes. We measured how bird diversity and abundance varied between waterholes during the humid (January to May) and dry (June to December) seasons. In total, we made 4,137 detections of 35 bird species. Among these, 10 species were endemic to the Tumbesian area, including one that is glob- ally endangered (the White-Winged Guan, Penelope albipennis). 95% of detections in all waterholes corresponded to four species of pigeons/ doves (Columbidae). We also recorded two migratory species, including one that is uncommon in northwestern Peru (the Slaty Thrush, Tur- dus nigriceps). The number of bird detections during the dry season was almost two times higher than that during the humid season. We did not find any correlations between relative abundance/diversity at waterholes and elevation or distance to agricultural areas. We postulate that permanent waterholes are a key to bird species in the northwestern Peruvian dry forests and should be protected, since they provide a scarce resource to several range-restricted species, including one that is globally threatened.