Northern Great Basin Ecoregion Rapid Ecoregional Assessment
The Rapid Ecoregional Assessment (REA) is the U.S. Bureau of Land Management’s (BLM’s) first step toward a broader initiative to systematically develop and incorporate landscape-scale information into the evaluation and eventual management of public land resources. In response, the BLM launched several REAs to improve the understanding of the existing condition of these landscapes, and how the current conditions may be altered by ongoing environmental changes and land use demands. These scientific assessments were conducted to increase the understanding of the existing landscapes, how they may be affected, and to provide information for future management actions.
The purpose of the REA is to identify, assemble, synthesize, and integrate existing information about natural resources and environmental change agents to provide information that will help BLM land managers in the ecoregion understand resource status and the potential for change from a broad landscape viewpoint. The BLM defines landscapes as large, connected geographical regions that have similar environmental characteristics. These landscapes span administrative boundaries and can encompass all or portions of several BLM field offices. REAs provide a tool to identify and analyze the key “management questions” regarding the resources, values, and processes that are fundamental to the conservation of BLM lands. The landscape-scale approach recognizes landscapes are being affected by complex influences that reach beyond traditional management boundaries and across watersheds and jurisdictions.
The study area for this REA is comprised of two ecoregions, the Northern Basin and Range and the Snake River Plains, identified going forward as the Northern Great Basin (NGB). The NGB encompasses southeastern Oregon, portions of southern Idaho, northern Nevada, and a small extension into northeastern California and northwestern Utah. It is the northern extent of the larger Basin and Range physiographic province and also includes the important upper Snake River drainage system. Most of the ecoregion is dominated by sagebrush steppe ecosystems on the desert floor, but distinct vegetation zones related to relief and elevation also exist including juniper, mountain mahogany, aspen and riparian habitats. In the upper elevations Douglas-fir and aspen stands occur up the subalpine zone, which supports primarily low growing shrubs, grasses, and forbs. Wildlife species of importance to the region include bighorn sheep (Ovis canadensis), mule deer (Odocoileus hemionus), elk (Cervus elaphus), pronghorn (Antilocapra americana), pygmy rabbit (Brachylagus idahoensis), golden eagle (Aquila chrysaetos), and greater sage grouse (Centrocercus urophasianus). Important habitats in the ecoregion include migration corridors and areas for overwintering pronghorn, as well as key habitat for greater sage-grouse. Federal agencies manage the majority of land in this ecoregion but large areas of tribal and private agricultural lands are present as well. Historical and current land use includes mining, livestock grazing, agriculture, and recreation. Current management priorities include energy development, wild horse and burro management, and invasive plant species (particularly cheatgrass).
Human populations in the ecoregion are concentrated along the Snake River corridor and land development remains an important change agent. Much of the Snake River Plains ecoregion is used as cropland and federally managed rangeland, in which the distribution and extent of native vegetation communities have been significantly altered. Land use issues focus on the impacts of farming and livestock grazing, residential and commercial development, invasive annual grasses, dispersed recreation, surface water and groundwater withdrawal for irrigation, and soil erosion.