Brewer's Sparrow (Spizella breweri) modeled potential distribution in Washington:minimum of 4 model agreement. Shrubsteppe passerine distribution models were developed from presence/absence data collected at 324 sites in eastern Washington, 2014-2019 (Vander Haegen et al.2021). Models of potential distribution were built using R code and an ensemble modeling approach that included 4 statistical models (General Linear, General Additive, Random forest, and Boosted Regression Tree). Spatial data layers used as explanatory variables in the model included fractional vegetation cover (sagebrush, herbaceous vegetation, annual herbaceous vegetation, litter, and bare ground [Young 2017]), elevation, soil depth, and 2 landscape variables: percent unconverted shrubsteppe within a 3km radius, and percent Conservation Reserve Program land within a 3km radius (estimated from the WSDA 2018 Cropland layer). Raster layers of species potential distribution were created using results from all 4 models concurrently, with each cell coded with the number (0-4) of models predicting species presence.

Additional 2km buffered brewers sparrow location data was supplied to Conservation Biology Insitute by the Washington Department of Fish and Wildife. This location data was merged with the 4 model agreement raster by Conservation Biology Institute.