USGS scientists used nearly 30 years of Earth observation data to analyze past climate patterns over 3,216 square miles (8,330 km2) of southwestern Wyoming in order to forecast sagebrush abundance in 2050, a key habitat for the greater sage-grouse. Sage-grouse are found in parts of 11 U.S. States and two Canadian provinces in western North America, but Wyoming is a stronghold for the populations. These birds rely on sagebrush ecosystems, which constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. The U.S. Fish and Wildlife Service is formally reviewing the status of greater sage-grouse to determine if the species is warranted for listing under the Endangered Species Act.
The USGS study examined the impact of historical precipitation change on key components of sagebrush ecosystems from 1984 to 2011. These historical patterns of sagebrush ecosystem vegetation, discerned from long-term Landsat imagery records, were then combined with Intergovernmental Panel on Climate Change (IPCC) precipitation scenarios to model and forecast the most likely changes in sagebrush habitat from 2006 to 2050.
Projected precipitation patterns for 2050 resulted in decreased amounts of sagebrush and other shrubs, grasses, and flowering plants (forbs), and increased amounts of bare ground. When these changes were translated to sage-grouse habitat, researchers concluded that there was a potential loss of 12% of sage-grouse nesting habitat and ~4% of sage-grouse summer habitat by 2050. Results also demonstrate the vulnerability of semiarid lands, such as sagebrush habitat, to precipitation changes because of their already low soil moisture content.
This research explores how to bring climate change results to a more localized scale; in this case, units are as small as a quarter of an acre. Using Landsat and downscaled climate scenarios to enable future forecasts of greater sage-grouse habitat can provide critical information on a more local or regional scale for managers to help them better plan for the future.