Projections of Contemporary and Future Climate Niche for Wyoming Big Sagebrush (Artemisia tridentatasubsp.wyomingensis): A Guide for Restoration

Abstract

Big sagebrush (Artemisia tridentata) is one of the most widespread and abundant plant species in the intermountain regions of western North America. This species occupies an extremely wide ecological niche ranging from the semi-arid basins to the subalpine. Within this large niche, three widespread subspecies are recognized. Montane ecoregions are occupied by subspecies vaseyana, while subspecies wyomingensis and tridentata occupy basin ecoregions. In cases of wide-ranging species with multiple subspecies, it can be more practical from the scientific and management perspective to assess the climate profiles at the subspecies level. We focus bioclimatic model efforts on subspecies wyomingensis, which is the most widespread and abundant of the subspecies and critical habitat to wildlife including sage-grouse and pygmy rabbits. Using absence points from species with allopatric ranges to Wyoming big sagebrush (i.e., targeted groups absences) and randomly sampled points from specific ecoregions, we modeled the climatic envelope for subspecies wyomingensis using Random Forests multiple-regression tree for contemporary and future climates (decade 2050). Overall model error was low, at 4.5%, with the vast majority accounted for by errors in commission (>99.9%). Comparison of the contemporary and decade 2050 models shows a predicted 39% loss of suitable climate. Much of this loss will occur in the Great Basin where impacts from increasing fire frequency and encroaching weeds have been eroding the A. tridentata landscape dominance and ecological functions. Our goal of the A. tridentata subsp. wyomingensis bioclimatic model is to provide a management tool to promote successful restoration by predicting the geographic areas where climate is suitable for this subspecies. This model can also be used as a restoration-planning tool to assess vulnerability of climatic extirpation over the next few decades.

Long‐term trajectories of fractional component change in the Northern Great Basin, USA

“…We show that fractional component cover slopes were significantly related to 1986-2016 climate in linear and non-linear relationships (Fig. While sagebrush tolerates a range of conditions (Still and Richardson 2015), its cover tended to decrease the most in the warmest (Fig. While sagebrush tolerates a range of conditions (Still and Richardson 2015), its cover tended to decrease the most in the warmest (Fig.…”

Climate drives adaptive genetic responses associated with survival in big sagebrush (Artemisia tridentata)

“…Probability of survival was calculated for individual cell values, 0.00833 o (approximately 1 km 2 ), using the yaImpute package in R (Crookston & Finley, ). The generalized linear mixed model was projected within the climatic niche boundaries of subspecies wyomingensis (Still & Richardson, ) using QGIS (QGIS Development Team ). This was completed using the log‐link transformed coefficients of the intercept and slopes of the fixed effects in the generalized linear mixed model (i.e., the slope of the two climate variables and wyomingensis ).…”

The response of big sagebrush (Artemisia tridentata) to interannual climate variation changes across its range

“…Indeed some SDMs show that precipitation is only a weak predictor of sagebrush occurrence (Still and Richardson 2015). The interaction between lag precipitation and average precipitation was positive (Table 1), meaning that the effect of precipitation either does not change from the dry to wet locations or has a positive effect only at the wettest edge of sagebrush distribution.…”

“…Sagebrush provides unique and critical habitat for many endemic species of conservation concern FIG. Distribution models for sagebrush typically indicate that climate change will cause large decreases in the total area suitable for sagebrush in the future (Neilson et al 2005, Bradley 2010, Schlaepfer et al 2012a, Still and Richardson 2015. Hypothetical effects of annual temperature variation on populations of a widespread species.…”