This report summarizes the results of a comprehensive inventory of birds and mammals on the Rio Blanco Lake State Wildlife Area (RBL-SWA) located in Rio Blanco County, Colorado. We used a variety of field methods to inventory birds and mammals on the RBL-SWA between January 2017 and December 2021. We confirmed the presence of 241 vertebrate species (195 birds, 38 mammals, 6 reptiles, and 2 amphibians) on the RBL-SWA.We believe the diversity of habitat...