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Predicted Pinyon Jay (Gymnorhinus cyanocephalus) densities across the western United States, 2008-2020

March 8, 2023

Management intended to benefit a target species may also affect non-target species that co-occur over space and time. Pinyon jay (Gymnorhinus cyanocephalus) populations experienced long-term declines and rely on habitat that could be lost to conifer removal programs for greater sage-grouse (Centrocercus urophasianus). Using 13 years of point count data (2008-2020) collected across the western United States and a suite of relevant covariates for habitat, we fit a hierarchical model to characterize and predict pinyon jay densities and evaluate population trends. The resulting maps include pinyon jay density at the beginning (PIJA_2008_PredictedDensity.tif) and end (PIJA_2020_PredictedDensity.tif) of our study period, a map depicting the percent change (difference) between the two years (PIJA_MedianDensityChange_2008to2020.tif), as well as masks representing all raster cells where one or more covariate pixel value(s) fell outside of the 2.5 and 97.5 percent quantiles of the covariate sample used when fitting the model, which could result in unusually high or low predictions of pinyon jay density (PIJA_mask_raster_2008.tif and PIJA_mask_raster_2020.tif).

Publication Year 2023
Title Predicted Pinyon Jay (Gymnorhinus cyanocephalus) densities across the western United States, 2008-2020
DOI 10.5066/P9NIG4UW
Authors Nicholas J Van Lanen, Adrian P Monroe, Cameron Aldridge
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Fort Collins Science Center