The Relative Impacts of Climate and Land-use Change on Conterminous United States Bird Species from 2001 to 2075

Species distribution models often use climate data to assess contemporary and/or future ranges for animal or plant species. Land use and land cover (LULC) data are important predictor variables for determining species range, yet are rarely used when modeling future distributions. In this study, maximum entropy modeling was used to construct species distribution maps for 50 North American bird species to determine relative contributions of climate and LULC for contemporary (2001) and future (2075) time periods. Results indicate species-specific response to climate and LULC variables; however, both climate and LULC variables clearly are important for modeling both contemporary and potential future species ranges. This data release provides summary data for each of the 50 species. Four types of files are included in a ZIP file distributed for each species, including 1) GeoTIFF files that represent species distributions for 2001 and 2075 (including model runs with and without climate or land use), 2) PDF files summarizing MaxENT model runs for 2001, demonstrating sensitivity of the models to climate and land use, 3) lambda values for each model run that contain variables used in that run and constants that can be used to compute values for the fitted model, and 4) a JPG file depicting a summary map of modeled species range in 2001, and panel maps depicting changes in species probability as land use and/or climate change by 2075. A summary Excel spreadsheet summarizes and compares results across the 50 species.