State of the Eastern Mojave Desert - 2019

Major types of development within the Eastern Mojave desert are include urban areas, roads, and areas prioritized for renewable energy installations.

There are three major urban areas within the study area: Las Vegas (169,685 acres), Pahrump (28,246 acres) and Boulder City (3,892 acres). Approximately 15,047 acres of roads transverse the study area.

Three areas hold priority status for utility-scale solar energy development on federal lands: the Amargosa Valley and Gold Point Solar Energy Zones and the Ivanpah Solar Energy Facility. Together, these cover 14,536 acres in Nevada and 6,720 acres in California. No utility-scale wind energy projects occur in the area of interest.

The map opposite includes roads and urban areas in red and solar development areas in yellow.

More information about the Major Roads layer can be found here:

More information about the Solar Energy Zones layer can be found here:

More information about the Urban Areas layer can be found here:

Areas managed for development have been analyzed nationwide by the National Land Cover Database. Across the Eastern Mojave Desert area of interest, the total developed area grew by 21% between 2001 and 2016.

The National Land Cover Database has information about many different aspects of the Earth's surface. The latest dataset available is from 2016. More information about National Land Cover Database products can be found here:

Approximately 909 acres were actively cultivated for agricultural purposes during the years 2014 and 2018, and this comprises less than one percent of the Eastern Mojave area of interest.

The agricultural land area calculation was derived from the National Agricultural Statistics Service Cultivated Layer. More information can be found here:

Mean annual temperatures in 2018 across the Eastern Mojave Desert ranged between 10 degrees Fahrenheit cooler and 17 degrees warmer than the 30-year averages shown in the map above.

This data shows how observed values deviate from the 30-year normals (long-term averages). More information about PRISM Climate Data Anomaly products can be found here:

The map opposite shows mean annual precipitation gathered by PRISM between 1981 and 2010, as well as the snow monitoring stations that measure snowmelt.

Mean annual precipitation between 1981 and 2010 ranged from 46 mm to 712 mm. Areas with more precipitation are visualized in blue, while areas with less precipitation appear yellowish. Three SNOTEL stations and six SCAN stations record information on snowmelt within the study area.

The normals are baseline datasets describing average monthly and annual conditions over the most recent three full decades. The current PRISM normals cover the period 1981-2010. Long-term average datasets are modeled with PRISM using a digital elevation model (DEM) as the predictor grid. Given their importance, the normals were subjected to extensive peer review. More information about PRISM Climate Data products can be found here:

More information about Snow Monitoring Station Data can be found here:

Part of the Amargosa River watershed, the Ash Meadows National Wildlife Refuge is a spring-fed oasis in the eastern Mojave Desert and a major discharge point for the Death Valley regional lower carbonate aquifer. This extensive aquifer spans approximately 100,000 km2 from the Oasis Valley in the north-west near Beatty, Nevada to Death Valley National Park, California to the south-west. Comprised of nearly 24,000 acres of spring-fed wetlands and alkaline desert, Ash Meadows contains the highest rate of endemism in the United States, and second highest in all North America (surpassed only by Cuatrocienégas UNESCO Biosphere Reserve in Coahuila, Mexico). This incredibly biodiverse, lush landscape was distinctly recognized as a Wetland of International Importance by the Ramsar Convention, a global intergovernmental treaty formed in 1971 to address increasing loss and degradation of wetland habitat for migratory water birds. Ash Meadows was included in 1986, one of the first four wetlands designated in the United States.

 In addition to prime bird habitat, Ash Meadows is also home to 26 known endemic species, including several endangered spring fishes, a threatened aquatic insect, and a variety threatened and endangered plants. Flora and fauna, both aquatic and terrestrial alike, depend on these water sources for survival in this harsh desert environment.

Despite its recognized ecological value, Ash Meadows was not always afforded the protection it has today. Before the refuge was established in 1984, the entire area was heavily farmed and its hydrologic characteristics were severely impacted by human use. Springs were pumped, dredged, and filled in, and outflows channelized. Peat marshes once blanketing the area were completely harvested and will never return. Other past activities in Ash Meadows included commercial fish farming, establishment of a resort and brothel, and landscape disturbances related to proposed development of a planned community of 30,000 – 50,000 houses, which thankfully never came to fruition. 

Over the past three decades, the U.S. Fish and Wildlife Service and partner agencies have made significant strides to reverse the effects of these impacts and restore the historic condition of the spring systems and surrounding landscape. Efforts have included returning natural topography, flows, and connectivity to waterways, invasive plant and animal removal and control, revegetation and riparian restoration, and other ongoing conservation and management for species, communities, and habitats.

To learn more about Ash Meadows National Wildlife Refuge, please visit:  https://www.fws.gov/refuge/ash_meadows/ 

Photo: Crystal Spring, courtesy Ambre Chaudoin.

At the state scale, maps of habitat quality in California and Nevada have been developed by the states' respective departments of fish and wildlife. These tools incorporate multiple datasets on species presence, habitat quality, and other metrics to support decisions surrounding conservation, development, connectivity, and climate change resiliency. The two tools measure slightly different aspects of habitat quality, but can both be used to identify habitat and corridors.

The California Areas of Conservation Emphasis (ACE) tool combines data on biodiversity, presence of habitat important to species prioritized by policies, habitat connectivity, and climate resilience in a single map (displayed opposite in the California portion fo the EMCC area). In the map opposite, areas of highest conservation value are colored in green.

The Nevada CHAT tool has a Landscape Condition layer, shown on the Nevada portion of this map. Each one-mile hexagon was assigned a ranking of overall landscape condition, from 1 (most crucial) to 6 (least crucial). This map can be used to identify areas multiple wildlife species can best utilize, as well compare conditions and trends over time as the map is updated. The most crucial habitat on the map opposite is colored in green.

Overlaid on the CHAT and ACE models are points suggested by EMCC partners as hotspots for biodiversity in 2018. These points are not scientifically referenced, but can be considered starting points for planning around natural resource conservation. Click on the points to learn about the resources in the area and the partners who suggested them.

More information about Nevada Crucial Habitat Assessment Tool products can be found here:

More information about California Areas of Conservation Emphasis Tool products can be found here:

Desert tortoise (Gopherus agassizii) is a focal species of managers across the Mojave Desert, and existing tortoise habitat signifies suitable areas for other desertscrub species. Partners of the USGS Western Ecological Research Center have developed a sophisticated model for suitable desert tortoise habitat. The citation is below:

Nussear, K.E., Esque, T.C., Inman, R.D., Gass, Leila, Thomas, K.A., Wallace, C.S.A., Blainey, J.B., Miller, D.M., and Webb, R.H., 2009, Modeling habitat of the desert tortoise (Gopherus agassizii) in the Mojave and parts of the Sonoran Deserts of California, Nevada, Utah, and Arizona: U.S. Geological Survey Open-File Report 2009-1102, 18 p.

The following acreages of land across the eastern Mojave Desert have been impacted by fire over the past four decades:

• 1984-1990: 65,259 acres
• 1990-2000: 6,117 acres
• 2000-2010: 188,009 acres
• 2010-2017: 45,896 acres
• Total from 1984-2017: 305,281 acres

Between 1984 and 2009, a total of 259,385 acres burned; in the past seven years, 45,896 acres burned.

More information about the Monitoring Trends in Burn Severity Data can be found here:

This Wildfire Hazard Potential map illustrates the level of calculated risk of fire, and it can provide important guidance for fire mitigation. As of 2019, about 4% percent of the Eastern Mojave study area has a Wildfire Hazard Potential of High or Very High.

More information about the Wildfire Hazard Potential Data can be found here:

Erodibility of soils can indicate areas where soils are more or less stable. Soil erodibility can provide insight into where restoration may need to occur or where land is too unstable for restoration activity. The NRCS has mapped soil erodibility in select locations, and the EMCC has compiled those maps for the Eastern Mojave area.

Interact with the soil erodibility layer in The EMCC Data Viewer; click on the "Soil Erodibility" layer.

Here is the source data from NRCS:

This map shows the percentage of herbaceous cover within desertscrub ecosystems. The desertscrub ecosystems are colored, and other ecosystems are not colored (appearing gray). HUC 12 watershed boundaries have been overlaid.

In this analysis, more herbaceous cover appears along watershed boundaries (generally higher elevation areas) than in lower valleys.

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC data can be found here:

This map shows the percent change in herbaceous cover within desertscrub ecosystems. HUC 12 watershed boundaries have been overlaid.

Approximately 29% of the desertscrub ecosystems saw a decrease in herbaceous cover.

Approximately 62% of the desertscrub ecosystems saw an increase in herbaceous cover.

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC data can be found here:

This map shows the percentage of tree cover within desertscrub ecosystems. Trees in this dataset were considered to be vegetation greater than 10 meters tall. HUC 12 watershed boundaries have been overlaid.

As anticipated, very little tree cover was detected in the Eastern Mojave Desert. However, monitoring tree cover can provide insight into the condition of tree species that grow in certain watersheds, elevations, or soils.

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC data can be found here:

This map shows the percent change in tree cover within desertscrub ecosystems between 2000 and 2016. HUC 12 watershed boundaries have been overlaid. Areas in white are ecosystems not classified as desertscrub.

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC data can be found here:

This map shows the percentage of bare ground within desertscrub ecosystems. In this dataset, bare ground is considered any non-vegetated area (bedrock, gravel, sand, etc.). HUC 12 watershed boundaries have been overlaid.

The total average bare ground cover is 77%. This average may be compared to future averages to calculate a trend in bare ground.

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC data can be found here:

This map shows the percent change in bare ground cover (non-vegetated areas) within desertscrub ecosystems. HUC 12 boundaries have been overlaid. The legend below states that greener areas (negative values) represent places where bare ground has decreased, and yellow and orange areas (positive values) represent areas in which bare ground has increased. The legend is below:

More information about MODIS Vegetation Continuous Fields data can be found here:

More information about HUC watershed boundaries can be found here:

Devils Hole-a detached unit of Death Valley National Park--is habitat for the only naturally occurring population of the endangered Devils Hole Pupfish (Cyprinodon diabolis). The 40-acre unit is a part of the Ash Meadows complex, an area of desert uplands and springfed oases designated a national wildlife refuge in 1984.

Devils Hole is a window into this vast aquifer and an unusual indicator of seismic activity around the world. The Devils Hole unit was added to Death Valley National Monument by presidential proclamation in 1952. Ten years later the NPS installed a hydrograph in the Hole to monitor water levels. In 1967, a farming corporation secured ownership of 12,000 acres (4,900 ha) in the Ash Meadows area, and by the following year, the hydrograph had begun to register a decline as large capacity wells were drilled and pumped in Ash Meadows.

In 1967, the Devils Hole pupfish was officially listed as an endangered species. That same year, the alarming water drop that occurred with the arrival of the adjacent agricultural operation threatened to expose the rock shelf critical for fish spawning and feeding. By 1970, drastic conservation efforts had been undertaken: refugia populations were established, and a floating artificial shelf, artificially lighted, was suspended in Devils Hole to substitute for the partially exposed natural rock shelf. The fish never used the artificial shelf.

In August of 1971, a federal court issued an injunction to halt further pumping that threatened to completely expose the natural shelf in Devils Hole. Further litigation finally resulted in the landmark Supreme Court decision of 1976 (Cappaert vs. U.S.), which recognized the prior water right of Devils Hole vis-a-vis its designation as part of a national monument. The permanent injunction did not halt pumping, but limited it to a level which guaranteed sufficient water to inundate the natural rock shelf.

The National Park Service continues a rigorous monitoring program of Devils Hole and the pupfish. The agency monitors water levels, temperature, pupfish population and reproduction, and other biotic and abiotic ecosystem parameters such as nutrients, carbon inputs, and the aquatic community as a whole.

Since 1969, scientists, managers, and conservationists have been meeting annually as part of the Desert Fishes Council to discuss research and work occurring in and around Devils Hole and the greater desert southwest region.  More recently, hydrologists, biologists, and managers have convened the Devils Hole Workshop which focuses on issues pertaining to the Death Valley regional lower carbonate aquifer and the systems it supports.   These conferences facilitate important information sharing that leads to partnerships and innovations across the region.

The Devils Hole pupfish and countless other vertebrates and invertebrates rely on the water sources of the Eastern Mojave Desert. Below is a list of fish, amphibians, and aquatic invertebrates currently considered threatened and endangered by the United States, California, or Nevada. The list is part of a larger compilation of riparian and aquatic species compiled by Ambre Chaudoin, National Park Service fish biologist, in November 2019.

Fish

• Amargosa Canyon speckled dace (Rhinichthys osculus spp.) Status: California Species of Critical Concern
• Ash Meadows speckled dace (Rhinichthys osculus nevadensis). Status: Federally endangered.
• Amargosa River pupfish (Cyprinodon nevadensis amargosae). Status: California Species of High Concern
• Amargosa River pupfish (Cyprinodon nevadensis amargosae). Status: California Species of High Concern
• Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes). Status: Federally endangered
• Devils Hole pupfish (Ash Meadows) (Cyprinodon diabolis). Status: Federally endangered; IUCN critically endangered
• Saratoga Springs pupfish (Cyprinodon nevadensis nevadensis).  Status: California Species of High Concern
• Shoshone pupfish (Cyprinodon nevadensis shoshone). Status: Not listed* *Previously considered extinct by 1969; possibly rediscovered in 1986. Species confirmation pending genetic analysis 
• Warm Springs pupfish (Ash Meadows) (Cyprinodon nevadensis pectoralis). Status: Federally endangered

Amphibians

• Amargosa Toad (Anaxyrus nelsoni [=Bufo nelsoni]). Status: IUCN endangered; NV Protected, Conservation Priority

Aquatic Invertebrates (Federal T&E only)

• Ash Meadows naucorid (Ambrysus amargosus). Status: Federally threatened

Photo opposite: Devils Hole Pupfish, courtesy O. Feuerbacher.

Streams occur where groundwater reaches the surface; some reaches flow on the surface year-round (these are called "perennial"), while other reaches flow underground only during some periods and rise to the surface during other periods (called "ephemeral.")

The EMCC has selected a group of stream gauges and groundwater wells that will help indicate the overall amount of water in certain areas. These gauges and wells are illustrated in the map opposite, overlaid with aquifers.

The EMCC hopes to analyze trends in streamflow and groundwater levels at the locations on the map. They also hope to determine perennial stretches of the Amargosa River as an additional Indicator of Landscape Health.

Layers of all current USGS stream gauges and groundwater wells can be found on the Eastern Mojave Data Viewer.

More information about Stream Gauges can be found here:

Streams occur where groundwater reaches the surface; some reaches flow on the surface year-round (these are called "perennial"), while other reaches flow underground only during some periods and rise to the surface during other periods (called "ephemeral.")

The EMCC has selected a group of stream gauges and groundwater wells that will help indicate the overall amount of water in certain areas. These gauges and wells are illustrated in the map opposite, overlaid with aquifers.

The EMCC hopes to analyze trends in streamflow and groundwater levels at the locations on the map. They also hope to determine perennial stretches of the Amargosa River as an additional Indicator of Landscape Health.

Layers of all current USGS stream gauges and groundwater wells can be found on the Eastern Mojave Data Viewer.

More information about Stream Gauges can be found here:

The USGS provides records for the gauges they manage. This map shows only USGS stream gauges with available data. Click on gauge of interest and then click View in the Popup to download a record from that gauge.

If you would like to quickly graph stream flow at any of the gauges on the map head over to SnowView.

Between 2001 and 2016, less than 1% of the Eastern Mojave area experienced a decline in wetlands, and less than 1% experienced an increase in wetlands. This map shows locations where wetland area increased and decreased, according to the National Land Cover Database.

More information about National Land Cover Database products can be found here:

The Amargosa vole is an endemic species that is one of the rarest mammals in North America. The Amargosa vole’s range is limited to the Amargosa River watershed and is entirely dependent on stands of wetland vegetation dominated by three-square bulrush, of which only an estimated 50-60 acres remain in the lower Amargosa River. A collaborative team has combined monitoring and modeling to develop habitat and population projections for the future. Based on their fundings on vole population dynamics and habitat requirements, they introduced voles to suitable habitat and are monitoring the population

Between 2001 and 2016, less than 1% of the Eastern Mojave area experienced a decline in wetlands, and less than 1% experienced an increase in wetlands. This map shows locations where wetland area increased and decreased, according to the National Land Cover Database.

More information about National Land Cover Database products can be found here:

The Amargosa vole is an endemic species that is one of the rarest mammals in North America. The Amargosa vole’s range is limited to the Amargosa River watershed and is entirely dependent on stands of wetland vegetation dominated by three-square bulrush, of which only an estimated 50-60 acres remain in the lower Amargosa River. A collaborative team has combined monitoring and modeling to develop habitat and population projections for the future. Based on their fundings on vole population dynamics and habitat requirements, they introduced voles to suitable habitat and are monitoring the population

Springs are an extremely valuable resources in the Eastern Mojave Desert. The Spring Stewardship Institute (SSI) has conducted pivotal studies and efforts regarding stream conditions and conservation. They have inventoried spring locations and modeled anticipated future conditions that may affect spring health. Some of this information is available on the SSI website to anyone who creates a username.

The map opposite shows a screenshot of a dataset they developed for the Desert Landscape Conservation Collaborative effort.

Click on the link below to explore the SSI website.

The Mohave Tui Chub, a federally endangered species and the only fish native to the Mojave River, currently only exists at one natural spring and four man-made lakes. The tui chub's persistence is owed to determined efforts by partners to create habitat and monitor and manage fish populations. Partners working on the recovery of the tui chub are looking for other suitable places to locate tui chub.

Questions EMCC partners would like to continue exploring related to water sources in the eastern Mojave Desert include:

1. Where is riparian restoration needed, and how can we gather enough local-scale data to prioritize project locations?
2. Where are treatments needed to slow wetland succession?
3. What are the next steps in inter-agency data coordination on streamflow and groundwater?

This map shows the percent change in woody cover within montane ecosystems between 2000 and 2016. When combined with other data, the locations of major tree cover change can provide insight into why those communities are changing.

More information about MODIS Vegetation Continuous Fields data can be found here:

The U.S. Forest Service conducts inventories of disease infestations of National Forest, and tracking the number of infestations over time can help tell the story of the health of forested ecosystems.

In 2017, the Forest Service documented 210 points of damage or disease due to insects in the Eastern Mojave study area. This number can be compared to future points in a trend analysis.

More information about the Insect and Disease Surveys can be found here:

In total, 84,169 acres of forested area have burned in the Eastern Mojave Desert between 1984 and 2017. Here are breakdowns by decade of forested areas impacted by fire :

1984-1990: 19,253 acres

1990-2000: 2,612 acres

2000-2010: 34,681 acres

2010-2017: 27,623 acres

More information about the Monitoring Trends in Burn Severity Data can be found here: