Ecoregions represent areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources. Ecoregions were designed to be used as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components.

Ecoregions are defined by using criteria that ranges from abiotic factors such as soils and geology, to biotic factors that include wildlife and vegetation, and even considers human activity such as land use. There are four different levels of ecoregions that vary from a very coarse Level I to a very fine resolution at Level IV. In the continental United States, there are 86 Level III ecoregions, 7 of which are found in Wyoming. A brief description of these ecoregions is provided below. As you can see, Wyoming is a diverse state in vegetation, topography, and land uses.

At a finer scale, Wyoming has 39 Level IV ecoregions. Click on the link to the right and explore a webpage containing the ecoregion map of Wyoming and a description of vegetation, climate and soil characteristics of these ecoregions.

Level III Ecoregions of Wyoming

High Plains (25)

The High Plains ecoregion is located in southeastern Wyoming. Its total area in the Continental U.S. is over 70 million acres and spreads from southern South Dakota into west Texas. Over 4 million acres of this ecoregion are located in eastern Wyoming. In Wyoming, the High Plains ecoregion is considered a transitional area because it is where the Southern Rockies, Northwestern Great Plains and High Plains ecoregions all meet. The High Plains ecoregion is characterized by rolling plains and tablelands. Due to dry, arid conditions, vegetation in this region is mostly short-grass or mixed-grass prairie. Land use in this ecoregion consists of dryland and irrigated farming, as well as some cattle grazing.

Middle Rockies (17)

The Middle Rockies ecoregion is found in three major patches in Northern Wyoming. The largest patch is located along the western border and contains Yellowstone and Teton National Parks. The other two patches are located in the Bighorn National Forest and the Black Hills National Forest. In total, this ecoregion represents over 12 million acres in Wyoming. Steep-crested, high mountains characterize the terrain. Vegetation type is mostly open-canopied coniferous forests composed of lodgepole pine. Water is ready available, providing habitat for grass and shrub intermontane valleys. Land uses of the ecoregion include summer livestock grazing, logging, recreation, and mining.

Northwestern Great Plains (43)

The Northwestern Great Plains ecoregions spreads over 12 million acres in northeastern Wyoming. This ecoregion is comprised mostly of rolling plains in a semi-arid environment, which produces mostly grassland plant communities with some shrub and woody species in northern areas. Major land uses include livestock grazing and wheat farming, as well as coal and coal bed methane production.

Snake River Plain (12)

In Wyoming, the Snake River Plain covers just over 7,000 acres, representing the smallest Level III ecoregion in the state. It is located northwest of Jackson, WY. The terrain of this ecoregion is plains and hills, with some lava fields. Sagebrush grassland represents the majority of vegetation. Most of the farming in the Snake River Plain in Wyoming is barley production. However, the Snake River Plain ecoregion is also useful for cattle grazing, recreation, and seasonal lodging.

Southern Rockies (21)

The Southern Rockies ecoregion consists of over 25 million acres, most of which are located in Central regions of Colorado. About 4 million acres spread into Carbon and Albany counties in southern Wyoming. This ecoregion is noted for its steep, rugged mountains and high elevations. Vegetation in this ecoregion varies with elevation, but can range from grass or grass-shrublands at lower elevations to coniferous and alpine forest communities at high elevations. Major land uses for this area are summer livestock grazing, logging, and recreation.

Wasatch and Uinta Mountains (19)

This ecoregion is located in southwest Wyoming along the Utah border. It covers just over 125,000 acres. The landscape is described as high mountains, dissected volcanic plateaus, and flanking valleys. The forested vegetation located in the higher elevations in Wyoming include Douglas-fir, ponderosa pine, aspen parkland, and lodgepole pine. The primary agricultural uses are livestock production and logging. Other uses for the area include recreation and summer homes.

Wyoming Basin (18)

The Wyoming Basin is the largest ecoregion in the state and covers nearly 30 million acres. This ecoregion is found mostly in Wyoming, but spreads into some parts of Colorado, Idaho, Utah, and Montana. The terrain is an intermontane basin with hills and low mountains. Vegetation includes both grasslands and shrublands that have adapated to a dry climate. Major land uses include livestock grazing, natural gas and petroleum production, and mining.