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Colorado River Delta Project: A compilation of vegetation indices, phenology assessment metrics, and estimates of evapotranspiration for circular bird plots in the Colorado River delta between 2000-2020 (ver. 1.0)

April 11, 2022

These data were compiled to understand the effects of riparian vegetation health on local abundance and species diversity of land birds. The primary objective of our study was to to determine the effects of riparian restoration on birds in the Colorado River delta. These tabular data represent vegetation indices and evapotranspiration (ET) data at varying spatial scales that correspond to avian use circles of 100 to 2000 meters. Three vegetation reflectance indices (VIs): NDVI, EVI, and EVI2 were obtained from Landsat imagery with a biweekly temporal frequency, and covering the entire period of bird surveys (2002-2020). The Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) and two-band EVI, named EVI2, were produced as tabular data sets. ET was then produced using EVI and EVI2. Also, ET was calculated from EVI2 using an empirical equation (Nagler et al., 2013). Data acquisition and processing were performed at the University of Arizona VIP lab ( using their large Linux cluster of computing and storage resources.