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Average and standard deviation of annual predicted common raven (Corvus corax) density (ravens per square kilometer) derived from random forest models given field site unit-specific estimates of raven density that were obtained from hierarchical distance sampling models at 43 field site units within the Great Basin region, USA. Fifteen landscape-level predictors summarizing climate, vegetation, topography and anthropogenic footprint were used to predict average raven density at each unit. These data support the following publication: Coates, P.S., O'Neil, S.T., Brussee, B.E., Ricca, M.A., Jackson, P.J., Dinkins, J.B., Howe, K.B., Moser, A.M., Foster, L.J. and Delehanty, D.J., 2020. Broad-scale impacts of an invasive...
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Predicted common raven (Corvus corax) impacts within greater sage-grouse (Centrocercus urophasianus) concentration areas across the Great Basin, USA, 2007–2016. Predicted impacts were based on a raven density of great than or equal to 0.40 (ravens per square kilometer) which corresponded to below-average survival rates of sage-grouse nests. These data support the following publication: Coates, P.S., O'Neil, S.T., Brussee, B.E., Ricca, M.A., Jackson, P.J., Dinkins, J.B., Howe, K.B., Moser, A.M., Foster, L.J. and Delehanty, D.J., 2020. Broad-scale impacts of an invasive native predator on a sensitive native prey species within the shifting avian community of the North American Great Basin. Biological Conservation,...
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Predictions of raven occurrence in the absence of anthropogenic environmental effects. Raven point counts were related to landscape covariates using Bayesian hierarchical occupancy models and the means of the posterior distributions for relevant effects were used to generate the predictions.
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Map of cumulative 38-day nest survival predicted from a Bayesian hierarchical shared frailty model of sage-grouse nest fates. The midpoint of coefficient conditional posterior distributions of 38-day nest survival were used for prediction at each 30 meter pixel across the landscape.
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These data represent predicted common raven (Corvus corax) density (ravens/square-km) derived from random forest models given field site unit-specific estimates of raven density that were obtained from hierarchical distance sampling models at 43 field site units within the Great Basin region, USA. Fifteen landscape-level predictors summarizing climate, vegetation, topography and anthropogenic footprint were used to predict average raven density at each unit. A raven density of greater than or equal to 0.40 ravens/square-km corresponds to below-average survival rates of sage-grouse (Centrocercus urophasianus) nests. We mapped areas which exceed this threshold within sage-grouse concentration areas to determine where...
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Predictions of raven occurrence in the absence of natural environmental effects. Raven point counts were related to landscape covariates using Bayesian hierarchical occupancy models and the means of the posterior distributions for relevant effects were used to generate the predictions.
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These data represent an resource selection function (RSF) for translocated sage-grouse in North Dakota during the summer. Human enterprise has led to large‐scale changes in landscapes and altered wildlife population distribution and abundance, necessitating efficient and effective conservation strategies for impacted species. Greater sage‐grouse (Centrocercus urophasianus; hereafter sage‐grouse) are a widespread sagebrush (Artemisia spp.) obligate species that has experienced population declines since the mid‐1900s resulting from habitat loss and expansion of anthropogenic features into sagebrush ecosystems. Habitat loss is especially evident in North Dakota, USA, on the northeastern fringe of sage‐grouse’ distribution,...
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Ranked index of model-projected nest site selection integrated with nesting productivity (i.e., nest survival), demonstrating the spatial distribution of adaptive vs. maladaptive habitat selection at each 30 m pixel. Hierarchical models of nest selection and survival were fit to landscape covariates within a Bayesian modeling framework in Nevada and California from 2009 through 2017 to develop spatially explicit information about nest site selection and survival consequences across the landscape. Habitat was separated into 16 classes ranking from high (1) to low (16). Habitat ranked highest where the top nest selection and survival classes intersected (adaptive selection), whereas the lowest rank occurred where...
Expanding human enterprise across remote environments impacts many wildlife species, including sage-grouse (Centrocercus urophasianus), an indicator species whose decline is at the center of national conservation strategies and land use policies. Anthropogenic resources provide subsidies for generalist predators, potentially leading to cascading effects on sensitive prey species at lower trophic levels. In semi-arid western ecosystems, common ravens (Corvus corax) are expanding in distribution and abundance, and may be negatively affecting sage-grouse reproductive success at broad spatial scales. Ravens are a common predator of sage-grouse nests, and potentially prey on chicks as well. This research aimed to address...
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A hierarchical occupancy model adapted from Royle & Dorazio (2008) and Rota et al. (2011) for use in R. References: Royle, J.A. and Dorazio, R.M., 2008. Hierarchical modeling and inference in ecology: the analysis of data from populations, metapopulations and communities. Academic Press. doi:10.1016/B978-0-12-374097-7.50001-5 J. Andrew Royle, Robert M. Dorazio, Rota, C. T., Fletcher Jr, R. J., Dorazio, R. M. and Betts, M. G. (2009), Occupancy estimation and the closure assumption. Journal of Applied Ecology, 46: 1173-1181. doi:10.1111/j.1365-2664.2009.01734.x
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These data represent an resource selection function (RSF) for translocated sage-grouse in North Dakota during the brooding season. Human enterprise has led to large‐scale changes in landscapes and altered wildlife population distribution and abundance, necessitating efficient and effective conservation strategies for impacted species. Greater sage‐grouse (Centrocercus urophasianus; hereafter sage‐grouse) are a widespread sagebrush (Artemisia spp.) obligate species that has experienced population declines since the mid‐1900s resulting from habitat loss and expansion of anthropogenic features into sagebrush ecosystems. Habitat loss is especially evident in North Dakota, USA, on the northeastern fringe of sage‐grouse’...
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Map of nesting habitat selection scores predicted from a resource selection function (RSF) developed from sage-grouse nest locations. Nest site selection was modeled using a generalized linear mixed model of used and random locations in a Bayesian modeling environment, and the midpoint of coefficient conditional posterior distributions were used for prediction. Continuous values were reclassified and ranked using a percent isopleth approach with respect to observed nest locations.
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We use locations from previously released radio-marked greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) in a resource selection function framework to evaluate habitat selection following translocation and identify areas of seasonal habitat to inform habitat management and potential restoration needs. We also evaluate possible changes in seasonal habitat since the late 1980s using spatial data provided by the Rangeland Analysis Platform coupled with resource selection modeling results. Our results serve as critical baseline information for habitat used by translocated individuals across life stages in this study area, and will inform future evaluations of population performance and potential...
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Predictions of an anthropogenic influence on raven occurrence index intersected with sage-grouse concentration areas. The anthropogenic influence index indicates where resource subsidies are contributing the most to raven occurrence.
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We applied spatially-explicit models to a spatiotemporally robust dataset of greater sage-grouse (Centrocercus urophasianus) nest locations and fates across wildfire-altered sagebrush ecosystems of the Great Basin ecoregion, western USA. Using sage-grouse as a focal species, we quantified scale-dependent factors driving nest site selection and nest survival across broad spatial scales in order to identify wildfire impacts and other environmental influences on variation in nesting productivity across a broad ecoregion spanning mesic and xeric shrub communities. To investigate the consequences of habitat selection and explore the potential for a source-sink reproductive landscape, we sought to classify nesting habitat...
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These data represent an resource selection function (RSF) for translocated sage-grouse in North Dakota during the nesting season. Human enterprise has led to large‐scale changes in landscapes and altered wildlife population distribution and abundance, necessitating efficient and effective conservation strategies for impacted species. Greater sage‐grouse (Centrocercus urophasianus; hereafter sage‐grouse) are a widespread sagebrush (Artemisia spp.) obligate species that has experienced population declines since the mid‐1900s resulting from habitat loss and expansion of anthropogenic features into sagebrush ecosystems. Habitat loss is especially evident in North Dakota, USA, on the northeastern fringe of sage‐grouse’...
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Raven point counts were related to landscape covariates using Bayesian hierarchical occupancy models and the mean of the predicted posterior distribution for raven occurrence was used to visualize results.
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An index of anthropogenic influences on raven populations. Raven point counts were related to landscape covariates using Bayesian hierarchical occupancy models and the means of the posterior distributions for relevant effects were used to generate the predictions.


map background search result map search result map Raven study site locations in the Great Basin, derived from survey locations 2007 - 2016 Predicted probability of raven occurrence across the Great Basin, USA, 2007 – 2016 (Fig. 3) Predictions of raven occurrence in the absence of natural environmental effects in the Great Basin, 2007-2016 (Fig. 4A) Predictions of raven occurrence in the absence of anthropogenic environmental effects in the Great Basin, 2007-2016 (Fig. 4B) Anthropogenic influence index for raven populations in the Great Basin, 2007-2016 (Fig. 4C) Prediction of raven occurrence intersected with high impact areas for sage-grouse populations in the Great Basin, 2007-2016 (Fig. 5A) Anthropogenic influence on raven occurrence index within sage-grouse concentration areas in the Great Basin, 2007-2016 (Fig. 5B) Hierarchical Occupancy Model Code for R and Accompanying Files Data maps of predicted raven density and areas of potential impact to nesting sage-grouse within sagebrush ecosystems of the North American Great Basin Raven impacts within greater sage-grouse concentration areas within the Great Basin region of the United States 2007 - 2016 Average and standard deviation of annual predicted raven density in the Great Basin, Western U.S. Spatially-explicit Predictive Maps of Greater Sage-grouse Nest Selection Integrated with Nest Survival in Nevada and Northeastern California, USA Greater Sage-grouse Nest Survival, Nevada and California 2019 Greater Sage-grouse Nest Selection, Nevada and California 2019 Greater Sage-grouse Nest Site Source-Sink, Nevada and California 2019 Geospatial Information and Predictive Maps of Greater Sage-grouse Habitat Selection in Southwestern North Dakota, USA Brooding RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Nesting RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Summer RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Geospatial Information and Predictive Maps of Greater Sage-grouse Habitat Selection in Southwestern North Dakota, USA Brooding RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Nesting RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Summer RSF of Translocated Greater Sage-grouse in North Dakota, 2017 - 2018 Spatially-explicit Predictive Maps of Greater Sage-grouse Nest Selection Integrated with Nest Survival in Nevada and Northeastern California, USA Greater Sage-grouse Nest Selection, Nevada and California 2019 Greater Sage-grouse Nest Site Source-Sink, Nevada and California 2019 Greater Sage-grouse Nest Survival, Nevada and California 2019 Raven study site locations in the Great Basin, derived from survey locations 2007 - 2016 Raven impacts within greater sage-grouse concentration areas within the Great Basin region of the United States 2007 - 2016 Prediction of raven occurrence intersected with high impact areas for sage-grouse populations in the Great Basin, 2007-2016 (Fig. 5A) Anthropogenic influence on raven occurrence index within sage-grouse concentration areas in the Great Basin, 2007-2016 (Fig. 5B) Hierarchical Occupancy Model Code for R and Accompanying Files Predicted probability of raven occurrence across the Great Basin, USA, 2007 – 2016 (Fig. 3) Data maps of predicted raven density and areas of potential impact to nesting sage-grouse within sagebrush ecosystems of the North American Great Basin Average and standard deviation of annual predicted raven density in the Great Basin, Western U.S. Predictions of raven occurrence in the absence of natural environmental effects in the Great Basin, 2007-2016 (Fig. 4A) Predictions of raven occurrence in the absence of anthropogenic environmental effects in the Great Basin, 2007-2016 (Fig. 4B) Anthropogenic influence index for raven populations in the Great Basin, 2007-2016 (Fig. 4C)