Researchers report the influence of altered fire regimes on sagebrush recovery and greater sage-grouse populations in the American West. Increasingly frequent wildfires in the American West kill sagebrush and alter sagebrush recovery by facilitating colonization of invasive grasses, but the impacts of this shifting ecosystem on local wildlife populations have not been adequately quantified. Peter Coates and colleagues used 30 years of wildfire and climate data to evaluate concurrent changes in the population of sage-grouse, which is a sagebrush-obligate species, throughout the majority of Nevada and parts of neighboring states. The model incorporated variable rates of sagebrush recovery and invasion resistance. Facilitated by an accelerated wildfire-grass cycle, a loss of sagebrush has led to a shrinking sage-grouse population over the last 30 years. Furthermore, wildfire appeared to nullify surges in sage-grouse populations that usually occur following years of high precipitation. Model projections indicate that the current sage-grouse population could be reduced to approximately one half of current numbers over the next three decades if the wildfire-grass cycle continues unabated. According to the authors, slowing fire-related population declines in sage-grouse may depend on the intensity of fire suppression and restoration of burned areas, particularly in areas with relatively high sage-grouse density.
Article #16-06898: “Wildfire, climate, and invasive grass interactions negatively impact an indicator species by reshaping sagebrush ecosystems,” by Peter S. Coates et al.