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Brian G. Prochazka

Publications and source records attributed to Brian G. Prochazka.

At least 19 recordsLinked to original sources

Estimating greater sage-grouse population sizes within Oregon, 2017–24

We fit a binomial mixture ( N -mixture) model to lek (breeding area) count data to estimate annual population sizes of greater sage-grouse ( Centrocercus urophasianus ; sage-grouse) within Oregon between 2017 and 2024. Population estimates were delineated among 24 priority areas for conservation, and additional sources of information were considered, including male-to-female sex ratios, lek attendance rates, numbers of unmodeled leks, and the existence of unsampled/unknown leks. In 2024, Oregon was estimated to contain approximately 41,875 sage-grouse (95-percent credible interval [CRI=38,980–54,634]), which was down from a high of 50,869 (95-percent CRI=41,794–66,238) in 2017. A nadir (low point) was identified during 2019, when the median statewide population estimate was 30,644 birds. A complete population oscillation was not evident during the inferential period based on local maxima that were observed during the start (2017) and stop (2024) years of analysis. In addition to estimating population sizes, we evaluated N -mixture model estimates for precision and accuracy after randomly removing single and repeat counts in 10-percent increments (relative to total sample size). We estimated an increase in absolute bias of approximately 1.6 percent for every 10-percent reduction in effort.

Oregon

Estimating greater sage-grouse population sizes within the state of Oregon, USA 2017–2024

We fit an N -mixture model to lek (breeding area) count data to estimate annual population sizes of greater sage-grouse ( Centrocercus urophasianus ; sage-grouse) within the state of Oregon, USA between 2017–2024. Population estimates were delineated among 24 Priority Areas for Conservation (PACs) and considered additional sources of information including male-to-female sex ratios, lek attendance rates, numbers of unmodeled leks, and the existence of unsampled/unknown leks. In 2024, the state of Oregon was estimated to contain approximately 41,875 sage-grouse (95% credible interval [CRI] = 38,980–54,634), which was down from a high of 50,869 (95% CRI = 41,794–66,238) in 2017. A nadir (low point) was identified during 2019, when the median statewide population estimate was 30,644 birds. A complete population oscillation was not evident during the inferential period based on local maxima that were observed during the start (2017) and stop (2024) years of analysis. In addition to estimating population sizes, we evaluated N -mixture model estimates for precision and accuracy after randomly removing single and repeat counts in 10% increments (relative to total sample size). We estimated an increase in absolute bias of approximately 1.6% for every 10% reduction in effort.

BioRxiv

Changes in spatial distribution and abundance together determine potential for population persistence for greater sage-grouse

Aim Population ecologists often focus on changes in the distribution and abundance of wildlife species, which are useful for trend analyses and status assessments. However, rarely are these responses evaluated simultaneously for a single species, despite their unique contributions to fully assess a species' viability. For example, focusing solely on total abundance can mask important losses in overall distribution within a metapopulation structure that may contribute to long-term population instability that results from the extirpation of small peripheral populations. Location Bi-State region of Nevada and California, USA. Methods We simultaneously evaluated changes in population abundance and distribution for greater sage-grouse (hereafter sage-grouse; Centrocercus urophasianus ) within the Bi-State Distinct Population Segment (DPS), a genetically distinct and isolated population straddling the border of Nevada and California. We combined population counts, demographic data, and information on space use from marked individuals to evaluate changes in population distribution and abundance over three time periods that corresponded to the three most recent population nadirs (1995–2019, 2002–2019 and 2008–2019). Results The Bi-State DPS exhibited evidence of ~1.2%–2.5% declines annually, over the short/medium-term (1995–2019; λ^ = 0.987, 95% CRI: 0.970–0.999), short-term (2002–2019; λ^ = 0.975, 95% CRI: 0.963–0.985) and recent-term (2008–2019; λ^ = 0.988, 95% CRI: 0.973–1.001). Since 1995, the spatial distribution of sage-grouse abundance in the Bi-State DPS shifted amongst subpopulations, with peripheral subpopulations suffering the largest declines. Main Conclusions Gains in abundance and distribution amongst expanding subpopulations did not offset losses in the remaining subpopulations, with a net loss in occupied distribution of 156 km 2 since 1995. Reductions in spatial distribution could have implications for metapopulation persistence as peripheral populations become more vulnerable to stochastic events, which would not have been apparent from the evaluation of overall metapopulation abundance on its own.

California, Nevada

Range-wide population trend analysis for greater sage-grouse (Centrocercus urophasianus)—Updated 1960–2024

Greater sage-grouse ( Centrocercus urophasianus ; hereafter sage-grouse) are at the center of State and national land-use policies largely because of their unique life-history traits as an ecological indicator for the health of sagebrush ecosystems. This updated population trend analysis provides State and Federal land and wildlife managers with the best available science to help guide management and conservation plans aimed at benefiting sage-grouse populations and the ecosystems they inhabit. This analysis relied on previously published population trend modeling methodology from Coates and others (2021, 2022a) and incorporates population lek count data for 1960–2024. Included in this report are methodological updates to lek count data aggregation, state-space model forecasting, and targeted annual warning system signals, which are detailed under individual Modification sections. State-space models estimated a 2.9-percent average annual decline in sage-grouse populations between 1966 and 2021 (Period 1, six population oscillations) across their geographical range. The average annual decline among climate clusters for the same number of oscillations ranged between 2.2 and 3.4 percent. Cumulative declines were 41.2, 64.1, and 78.8 percent range-wide in Period 5 (19 years), Period 3 (35 years), and Period 1 (55 years), respectively.

California, Colorado, Idaho, Montana, Nevada, Nort

Conservation translocation immediately reverses decline in imperiled sage-grouse populations

Conservation translocation (hereafter translocation), the intentional movement of organisms from one location to another as a management tool, can be an extremely useful conservation action to increase the abundance of isolated populations following successful habitat restoration. However, managers seek to weigh the benefits against costs to the source population from which individuals are removed. Using two small and imperiled greater sage-grouse ( Centrocercus urophasianus ; hereafter sage-grouse) populations, we demonstrated the usefulness of translocation as a conservation management tool and the value of evaluating the potential consequences of translocation action. Using integrated population models and a before-after-control-impact (BACI) design, we quantified the extent to which translocation influenced the finite rate of change ( λ "> λ ) of apparent abundance ( N "> N ) in both reinforced and source populations. We also assessed changes in underlying demographic rates in one population, allowing for identification of the specific mechanisms causing differences in population trends following translocation. In both reinforced populations, λ ̂ "> λ̂ substantially increased following translocation. In the population for which we had sufficient demographic data, the increase in λ ̂ "> λ̂ resulted from a 179 % increase in egg hatchability following reinforcement. In one translocation, we did not observe adverse effects on the source populations. The source population for the second translocation exhibited reduced population growth rates after translocation, although BACI ratios indicated causes for population declines independent of translocation effects, highlighting the need to investigate processes together with observed patterns. Overall, we demonstrated the ability to rescue isolated sage-grouse populations via translocation, preserving population viability and metapopulation persistence.

California, Montana, Nevada, North Dakota, South D

Geographic principles applied to population dynamics: A spatially interpolated integrated population model

A major impediment to wildlife conservation and management, from a quantitative perspective, is dealing with high degrees of uncertainty associated with population estimates. Integrated population models (IPMs) can help alleviate that challenge, but they are often limited to narrow spatial or temporal windows owing to the financial and logistical burdens of acquiring requisite datasets. To expand the spatiotemporal scope of practical IPM implementation, we developed a novel method that expresses demographic relatedness among sampled and unsampled locations using geographic principles of spatial autocorrelation. We interpolated demographic parameters at unsampled locations using parameter estimates from data-informed locations. Errors attributable to the interpolative process were corrected using a joint likelihood and locally recorded count data (‘cheaper’ and broadly distributed). We evaluated the spatially interpolated IPM (SIIPM) for precision and accuracy under variable levels of spatial autocorrelation using simulated data and a Leave-One-Out Cross-Validation (LOOCV) technique. Conventional IPMs and state-space models (SSM) were fit to the same simulated datasets to provide a comparative assessment of the novel method. In a final, empirical demonstration we fit the SIIPM to data collected from Greater Sage-Grouse ( Centrocercus urophasianus ; sage-grouse) populations located in Nevada, U.S.A. during 2013–2021. SIIPMs outperformed conventional IPMs when fit to data possessing moderate-to-high levels of spatial autocorrelation. Under moderate levels of autocorrelation, the average improvement in parameter estimation was 13.6% for survival, 65.3% for recruitment and 23.7% for rate of population change (𝜆). When spatial autocorrelation was low, the SIIPM still outperformed contemporary approaches in areas that were geographically close (<67 km) to sampling locations. Under low autocorrelation-near distance scenarios, we observed SIIPM parameters that were 30.8% (recruitment), 32.5% (𝜆; IPM comparison) and 54.0% (𝜆; SSM comparison) more precise than contemporary models. Spatial autocorrelation is often assumed but rarely tested when comparing population dynamics across regions of large geographic extent. We demonstrated that SIIPMs can improve precision of species' vital rate estimation when extrapolating model inference beyond populations for which long-term monitoring data exists. Specific to sage-grouse, these results support previous conclusions of broad-scale spatial autocorrelation in population dynamics and a reproductive-survival trade-off previously documented at smaller scales.

Methods in Ecology and Evolution

Status of greater sage-grouse in the Bi-State Distinct Population Segment—An evaluation of population trends, habitat selection, and efficacy of conservation actions

Preface This study was completed to provide timely scientific information regarding greater sage-grouse population trends, habitat selection, and the efficacy of previous conservation actions implemented to benefit the Bi-State Distinct Population Segment (DPS). Specifically, we provide these analyses to inform the current (2024) status review and pending listing decision for the DPS being undertaken by the U.S. Fish and Wildlife Service. These findings provide updated, detailed, and comprehensive information regarding the status of a geographically isolated and genetically distinct population of a species of high conservation concern and their habitat. Importantly, this report also provides information on the efficacy of previously implemented conservation actions targeting the Bi-State DPS in a framework that is transferable throughout the species’ range.

California, Nevada

Range-wide population trend analysis for greater sage-grouse (Centrocercus urophasianus)—Updated 1960–2023

Greater sage-grouse ( Centrocercus urophasianus ) are at the center of state and national land-use policies largely because of their unique life-history traits as an ecological indicator for health of sagebrush ecosystems. This updated population trend analysis provides state and federal land and wildlife managers with best-available science to help guide management and conservation plans aimed at benefitting sage-grouse populations. This analysis relied on previously published population trend modeling methodology from Coates and others (2021, 2022a) and incorporates population lek count data for 1960–2023. Included in this update are changes in terminology. Specifically, we now use the terms Period 1 (previously Long), Period 2 (previously Medium/Long), Period 3 (previously Medium), Period 4 (previously Short/Medium), Period 5 (previously Short), and Period 6 (previously Recent) to identify specific trends. State-space models estimated 2.8-percent average annual decline in sage-grouse populations between 1966 and 2021 (Period 1, six population oscillations) across their geographical range. Average annual decline among climate clusters for the same number of oscillations ranged between 2.1 and 3.1 percent. Cumulative declines were 41.1, 64.5, and 78.4 percent range-wide during Period 5 (19 years), Period 3 (35 years), and Period 1 (55 years), respectively. Population growth during 2022 and 2023 continue to point to 2021 as the most recent range-wide nadir.

Data Report

Cooperative conservation actions improve sage-grouse population performance within the Bi-State Distinct Population Segment

Developing a robust monitoring framework that integrates efficacy assessments of cooperative conservation and restoration actions in relation to population viability is critical for successful long-term recovery of target ecosystems and species. However, often it is difficult to quantify conservation action efficacy because of the complex, dynamic nature of ecosystem processes and practical limitations associated with assessing target species’ population dynamics. Here, we present an analytical framework that allows for quantification of conservation action efficacy using greater sage-grouse ( Centrocercus urophasianus ; hereafter, sage-grouse) within the Bi-State Distinct Population Segment which borders Nevada and California. This framework utilizes web-based repositories of conservation efforts carried out in sagebrush ecosystems and readily fits within contemporary sagebrush conservation design strategies. We employed a state-space model within a Bayesian framework to estimate abundance (N) as inputs for a progressive change before-after-control-impact paired series (BACIPS) design. Count data from 57 leks (monitored between 2003–2021) coupled with 85 unique actions (initiated between 2012–2019) provided clear evidence that conservation actions increased population abundance, on average, by 4.4% annually across the study area, resulting in a 37.4% cumulative increase since 2012. Population gains varied by the type of conservation action and according to the number of lag years following its implementation.

California, Nevada

Evaluating the sagebrush conservation design through the lens of a sagebrush indicator species

Sagebrush ecosystems support a suite of unique species such as the emblematic greater sage-grouse ( Centrocercus urophasianus ; sage-grouse) but are under increasing pressure from anthropogenic stressors such as annual grass invasion, conifer encroachment, altered wildfire regimes, and land use change. We examined the ability of an ecosystem-based framework for sagebrush conservation, the sagebrush conservation design (SCD) strategy, and the associated model of sagebrush ecological integrity (SEI), to identify and rank priority habitats for sage-grouse, a sagebrush indicator species. We compared sage-grouse population trends from 1996–2021 across the three ranked SEI categories. We then modeled those trends directly as a function of the same landcover predictors underlying SEI, used the median trend estimates to recategorize the sage-grouse’s range, and used spatial correlation methods to compare our sage-grouse performance categories with those of SEI. Finally, we compared the sage-grouse condition categories, predicted by our landcover-based model, to empirical trends derived from population count data. We found that the SCD and SEI were effective tools for identifying and ranking priority habitats for sage-grouse. Population trends were stable in the core areas identified by SEI but declining in the lower (i.e., growth and other) condition categories. As a result, core areas encompassed an increasingly larger share of the total sage-grouse population in a disproportionately smaller area. Our model supports the general functional relationships between landcover and sage-grouse performance suggested by SEI. We found strong spatial congruence between our categories of predicted sage-grouse population performance, the condition categories of SEI, and empirical trends derived from population count data. Our analysis demonstrates that proactive ecosystem-based approaches to the conservation of the sagebrush biome can help optimize the return on limited conservation resources and benefits for sagebrush obligate species and help reduce some of the real and perceived conflicts inherent in single-species management.

Arizona, California, Colorado, Idaho, New Mexico,

Wildfire immediately reduces nest and adult survival of greater sage-grouse

Wildfire events are becoming more frequent and severe on a global scale. Rising temperatures, prolonged drought, and the presence of pyrophytic invasive grasses are contributing to the degradation of native vegetation communities. Within the Great Basin region of the western U.S., increasing wildfire frequency is transforming the ecosystem toward a higher degree of homogeneity, one dominated by invasive annual grasses and declining landscape productivity. Greater sage-grouse ( Centrocercus urophasianus ; hereafter sage-grouse) are a species of conservation concern that rely on large tracts of structurally and functionally diverse sagebrush ( Artemisia spp.) communities. Using a 12-year (2008–2019) telemetry dataset, we documented immediate impacts of wildfire on demographic rates of a population of sage-grouse that were exposed to two large wildfire events (Virginia Mountains Fire Complex—2016; Long Valley Fire—2017) near the border of California and Nevada. Spatiotemporal heterogeneity in demographic rates were accounted for using a Before-After Control-Impact Paired Series (BACIPS) study design. Results revealed a 40% reduction in adult survival and a 79% reduction in nest survival within areas impacted by wildfires. Our results indicate that wildfire has strong and immediate impacts to two key life stages of a sagebrush indicator species and underscores the importance of fire suppression and immediate restoration following wildfire events.

California, Nevada

Range-wide population trend analysis for greater sage-grouse (Centrocercus urophasianus)—Updated 1960–2022

Greater sage-grouse ( Centrocercus urophasianus ) are at the center of state and national land-use policies largely because of their unique life-history traits as an ecological indicator for health of sagebrush ecosystems. This updated population trend analysis provides state and federal land and wildlife managers with best-available science to help guide current management and conservation plans aimed at benefitting sage-grouse populations. This analysis relied on previously published population trend modeling methodology from Coates and others (2021, 2022a) and incorporated population lek count data through 2022. Bayesian state-space models estimated 2.9 percent average annual decline in sage-grouse populations across their geographical range, which varied among subpopulations at the largest scale of analysis, termed climate clusters (2.2–4.7). Cumulative declines were 40.9, 65.0, and 79.6 percent range-wide across short (19 years), medium (35 years), and long (55 years) temporal periods, respectively. These results indicate that the most recent nadir for range-wide populations occurred during 2021. However, growth during 2022 was modest, making 2021 a tentative final nadir at this point.

Data Report

A genetic warning system for a hierarchically structured wildlife monitoring framework

Genetic variation is a well-known indicator of population fitness yet is not typically included in monitoring programs for sensitive species. Additionally, most programs monitor populations at one scale, which can lead to potential mismatches with ecological processes critical to species' conservation. Recently developed methods generating hierarchically nested population units (i.e., clusters of varying scales) for greater sage-grouse ( Centrocercus urophasianus ) have identified population trend declines across spatiotemporal scales to help managers target areas for conservation. The same clusters used as a proxy for spatial scale can alert managers to local units (i.e., neighborhood-scale) with low genetic diversity, further facilitating identification of management targets. We developed a genetic warning system utilizing previously developed hierarchical population units to identify management-relevant areas with low genetic diversity within the greater sage-grouse range. Within this warning system we characterized conservation concern thresholds based on values of genetic diversity and developed a statistical model for microsatellite data to robustly estimate these values for hierarchically nested populations. We found that 41 of 224 neighborhood-scale clusters had low genetic diversity, 23 of which were coupled with documented local population trend decline. We also found evidence of cross-scale low genetic diversity in the small and isolated Washington population, unlikely to be reversed through typical local management actions alone. The combination of low genetic diversity and a declining population suggests relatively high conservation concern. Our findings could further facilitate conservation action prioritization in combination with population trend assessments and (or) local information, and act as a base-line of genetic diversity for future comparison. Importantly, the approach we used is broadly applicable across taxa.

Ecological Applications

Geothermal energy production adversely affects a sensitive indicator species within sagebrush ecosystems in western North America

Growing demand for renewable energy has resulted in expansion of energy infrastructure across sagebrush ecosystems of western North America. Geothermal power is an increasingly popular renewable energy source, especially within remote areas, but little is known about the impacts it may have on local wildlife populations. Investigations are warranted given similarities to more conventional surface disturbance activities with well-documented impacts. Using a novel 2-pronged analytical approach, we estimated effects of geothermal energy production activities (hereafter, geothermal) on populations of greater sage-grouse ( Centrocercus urophasianus ; hereafter, sage-grouse), a species of high conservation concern. First, we applied a before-after-control-impact paired series design at two geothermal sites in Nevada, USA, to estimate absence rates of male sage-grouse from lek sites (breeding grounds) and changes in predicted apparent abundance ( &#x3BB; &#x302; "> �̂ ) in relation to geothermal energy infrastructure. We then estimated effects of geothermal energy infrastructure and other environmental covariates on demographic rates. We found &#x3BB; &#x302; "> �̂ declined ∼24 % within 5 km of geothermal sites, while lek absence rates (e.g., indicating local extirpation) increased by ∼730 % within 2 km. Our demographic models revealed decreased nest survival in association with proximity to geothermal infrastructure, reduced topographic impedance surface (TIS; a proxy for sound and light dispersion emanating from geothermal infrastructure), and increased density of common ravens ( Corvus corax ), an effective nest predator. Models also estimated decreases in adult survival in relation to TIS. Finally, we applied population matrix models within a quantitative decision support framework to help guide locations for future geothermal development that balance the need for domestic energy production while minimizing adverse effects on wildlife populations.

Biological Conservation

A targeted annual warning system developed for the conservation of a sagebrush indicator species

A fundamental goal of population ecologists is to identify drivers responsible for temporal variation in abundance. Understanding whether variation is associated with environmental stochasticity or anthropogenic disturbances, which are more amenable to management action, is crucial yet difficult to achieve. Here, we present a hierarchical monitoring framework that models rates of change in abundance from spatially structured populations and identifies when local declines fall out of synchrony with trends at larger spatial scales. Importantly, the framework provides signals that alert managers to the categorical significance of observed declines while avoiding signals where declines result from drivers operating at larger spatial scales (e.g., periodic reductions in primary productivity owing to drought). We demonstrate utility through application to a rapidly declining sagebrush ( Artemisia spp.) indicator species (greater sage-grouse; Centrocercus urophasianus ) using 30 years (1990–2019) of count data collected from greater than 4,400 leks (habitual breeding sites) distributed across the western United States. Results revealed population declines, immediately preceding triggers (2–4-year period), ranging between 58 and 68%. Conversely, population trends unassociated with triggers showed little-to-no sign of decline. Retrospective application of the monitoring framework indicated an average annual rate of 1.7% of leks or 1.3% of neighborhood clusters (lek aggregations) would have required management intervention to reverse range-wide declines and stabilize the U.S. population as a whole.

Ecological Indicators

A Bayesian multi-stage modelling framework to evaluate impacts of energy development on wildlife populations: An application to Greater Sage-Grouse (Centrocercus urophasianus)

Increased demand for domestic production of renewable energy has led to expansion of energy infrastructure across western North America. Much of the western U.S. comprises remote landscapes that are home to a variety of vegetation communities and wildlife species, including the imperiled sagebrush ecosystem and indicator species such as greater sage-grouse ( Centrocercus urophasianus ). Geothermal sources in particular have potential for continued development across the western U.S. but impacts to greater sage-grouse and other species are unknown. To address this information gap, we describe a novel two-pronged methodology that analyzes impacts of geothermal energy production on pattern and process of greater sage-grouse populations using (a) before-after control-impact (BACI) measures of population growth and lek absence rates and (b) concurrent-to-operation evaluations of demographic rates. Growth and absence rate analyses utilized 14 years of lek survey data collected prior (2005–2011) and concurrent (2012–2018) to geothermal operations at two sites in Nevada, USA. Demographic analyses utilized relocation data, restricted inference to concurrent years, and incorporated 17 additional control sites. Demographic results were applied to >100 potential geothermal sites distributed across the study region to generate spatially explicit predictions of unrealized population-level impacts.

MethodsX

Range-wide population trend analysis for greater sage-grouse (Centrocercus urophasianus)—Updated 1960–2021

Greater sage-grouse ( Centrocercus urophasianus ) are at the center of state and national land use policies largely because of their unique life-history traits as an ecological indicator for health of sagebrush ecosystems. This updated population trend analysis provides state and federal land and wildlife managers with best-available science to help guide current management and conservation plans aimed at benefitting sage-grouse populations. This analysis relied on previously published population trend modeling methodology from Coates and others (2021) and includes the addition of three analytical updates: (1) identification of population nadirs (lowest points within cycles) at the lek (breeding ground) and neighborhood cluster (group of leks) spatial scales, (2) truncation of prior distributions on rate of change in apparent abundance values to more realistic boundaries for leks with missing data, and (3) addition of 2 years of population lek count data (2020 and 2021) to the current dataset (1953–2021). Bayesian state-space models estimated 2.9 percent average annual decline in sage-grouse populations across their geographical range, which varied among subpopulations at the largest scale of analysis, termed climate clusters (2.2–4.6). Cumulative declines were 42.5, 65.6, and 80.1 percent range-wide across short (19 years), medium (35 years), and long (55 years) temporal periods, respectively. These results indicate that range-wide populations continued to decline during 2020 and 2021, although two climate clusters (eastern area and Bi-State area) have shown growth in population abundance in recent years, indicating they have surpassed a recent population abundance nadir.

Data Report

Maladaptive nest-site selection and reduced nest survival in female sage-grouse following wildfire

Increased wildfire frequency and associated replacement of sagebrush ( Artemisia spp.) with invasive annual grasses contribute to declines of greater sage-grouse ( Centrocercus urophasianus ; hereafter, sage-grouse) populations across the Great Basin. However, little is known about wildfire effects on sage-grouse nest-site selection and nest survival, which can influence population persistence. The primary objective of this study was to evaluate the effects of the Rush Fire on sage-grouse nest survival using before (2007–2009) and after (2015–2018) data collected from a population of sage-grouse occupying the border of northeastern California and northwestern Nevada. We employed a before–after–control–impact (BACI) experimental design to account for spatiotemporal heterogeneity in the system and to derive estimates of relative change in survival parameters. Sage-grouse nest survival decreased after the Rush Fire but decreased more in the burned area relative to the unburned area. Although female sage-grouse continued to occupy burned areas, nest survival was reduced from 52% to 19%. Using a BACI ratio approach we found that nest survival decreased approximately 51% in the burned area, relative to the unburned area, following wildfire. Habitat analyses were restricted to the postfire period and found that female sage-grouse that nested within unburned areas selected for wider nesting substrate, taller perennial grass height, and greater low sagebrush canopy cover. Conversely, female sage-grouse that nested in burned areas used shorter sagebrush canopy cover than what was available across the entire study area but showed stronger selection for perennial grass height than their unburned counterparts. Strong nest-site fidelity in sage-grouse may explain the continued use of suboptimal habitat in wildfire-altered landscapes, resulting in a reproductive cost, and overall reproduction well below replacement rate. Results suggest that fire suppression or rapid postfire habitat restoration, especially within nesting habitat, may be essential to conserving robust sage-grouse populations into the future.

California, Nevada