Understanding biological effectiveness before scaling up range‐wide restoration investments for Gunnison sage‐grouse

Abstract

Imperiled species recovery is a high‐stakes endeavor where uncertainty surrounding effectiveness of conservation actions can be an impediment to implementation at necessary scales, especially where habitat restoration is required. Gunnison sage‐grouse (Centrocercus minimus) represents one such species in need of large‐scale habitat restoration. It is a federally threatened sagebrush (Artemisia spp.) obligate bird with a limited range in Colorado and Utah. Threats to recovery of Gunnison sage‐grouse include conifer expansion into sagebrush along with additional habitat loss and degradation attributed to human development and agricultural conversion. Recovery of Gunnison sage‐grouse and other sensitive species can be aided by spatial tools that forecast plausible outcomes of conservation actions. We illustrate this by using a novel framework for predicting outcomes of proactive tree removal and subsequent sagebrush restoration for the Gunnison sage‐grouse. To assess threats on Gunnison sage‐grouse lek presence, we developed a spatially explicit breeding habitat model to compare active lek and random pseudo‐absence locations from 2015. Models identified land cover, climatic, and abiotic variables at landscape‐level scales (0.56 and 4 km) most important for predicting breeding habitat. Our model correctly differentiated between lek and pseudo‐absence locations 94% of the time. All but one of the active leks (n = 94) were in areas with >0.65 probability of lek occurrence. Using this probability value as a threshold, we predicted 15% of the current grouse range as high‐quality breeding habitat. Simulated removal of trees in areas with ≤30% tree canopy cover (0.56‐km scale) increased extent of high‐quality habitat fourfold (59%). Hypothetical restoration of sagebrush cover in the same areas increased habitat quality an additional 11%. Our breeding habitat model indicated that targeted tree removal and sagebrush restoration have potential to improve Gunnison sage‐grouse breeding habitat. While our habitat treatment scenarios were not meant to be prescriptive, they highlight that considerable uplift in Gunnison sage‐grouse breeding habitat may be possible across much of its range with cooperation from multiple stakeholders and illustrates the utility of this approach for predicting biological return on investment.

Signatures of adaptive divergence among populations of an avian species of conservation concern

“…Environmental covariates tested for association with SNPs were selected based on previously documented effects on sage‐grouse reported in the literature as well as environmental covariates which varied across the species range. Covariates used in model fits included sagebrush cover (Aldridge et al, ; Aldridge, Saher, Childers, Stahlnecker, & Bowen, ; Baruch‐Mordo et al, ; Doherty, Naugle, & Walker, ; Harju, Olson, Dzialak, Mudd, & Winstead, ; Knick, Hanser, & Preston, ; Oyler‐McCance, Burnham, & Braun, ), conifer cover and configuration (Baruch‐Mordo et al, ; Doherty et al, ), dominant shrub type (Aldridge et al, , ; Baruch‐Mordo et al, ; Doherty et al, ; Harju et al, ; Knick et al, ; Oyler‐McCance et al, ), a dryness index (Aldridge & Boyce, ), growing degree days (Aldridge & Boyce, ), seasonal and annual precipitation (Blomberg, Sedinger, Atamian, & Nonne, ), seasonal and annual temperature (Blomberg et al, ), seasonal and annual humidity, and phenology metrics derived from NDVI (Aldridge et al, ). A total of 72 covariates were initially considered (Table .1).…”

Threat‐Based State and Transition Models Predict Sage‐Grouse Occurrence while Promoting Landscape Conservation

“…Having a quantitative link between the TBSTM and sage-grouse occupancy allows insight into the biological effectiveness of transitioning habitats between TBSTM states as well as understanding how much habitat needs to be treated within priority areas. Ultimately, having a quantitative link between the TBSTM and sage-grouse occupancy allows for scenario planning before conservation actions are implemented at landscape scales (Doherty et al 2018, Ricca et al 2018.Consistent with past and present research, landscape context within the TBSTM framework is important to sage-grouse (Doherty et al 2010, Ricca et al 2018. We found strong positive selection for both State A habitat (healthy sagebrush-perennial bunchgrass communities), and State B habitat (perennial bunchgrassdominated communities), but neutral selection for State C habitat (sagebrush with invasive annual grass, or fully depleted understories).…”

Integrating Ecosystem Resilience and Resistance Into Decision Support Tools for Multi-Scale Population Management of a Sagebrush Indicator Species

“…Forest Service districts). Another recent study applied similar approaches to inform conifer removal for Gunnison's sagegrouse (Centrocercus minimus) but did not consider general R&R explicitly or implicitly (Doherty et al, 2018), so we excluded it from our review. In the Ricca et al (2018) study, the goal was to rank candidate treatment units based on improvement of annual habitat selection following removal of Phase I conifer in the Bi-State DPS.…”