THE MOJAVE DESERT: A UNIQUE ECOSYSTEM

Geography

Approximately 25,000 square miles

Parts in California, Utah, Arizona, and Nevada

Mountain ranges, salt pans, seasonal saline lakes

Las Vegas is the largest city in the Mojave

Elevation mostly 2000 to 5000 feet

Colorado river and Mojave river (intermittent river)

Smallest North American desert

Water and Precipitation

Usually gets around 5 inches of rain a year

In the rain shadow of the California Coast Ranges

May and June are the driest months, October to March is wet season

Seasonal lakes created based on rainfall

There is a year round supply of ground water

Wells and agriculture are causing water tables to drop to low levels

Climate

Temperature can go anywhere from 8°F to 119°F depending on season and time of day

25 mph winds have been recorded, and are common

July to September is thunderstorm season

Humidity is almost always below 40%, with the exception of some winter nights and after rain

Urban Areas

27 cities

Most populated area is Las Vegas (~1.9 mil.)

Mojave is attached to Los Angeles

Lancaster is the largest California city

Many other smaller towns

Major roads are Interstates 15 and 40 and Highways 58, 395, and 95

Death Valley National Park, Joshua Tree National Park, and Mojave National Park

Hoover Dam

Many shallow root systems are being destroyed by off-road vehicles churning up sand

Death Valley

Located in Eastern California

Lowest elevation in North American (282 ft below sea level) in Badwater Basin

Highest recorded temperature in the world (134°F)

Mean annual temperature of 77.2

1.9 inches annual average rainfall

Mostly Flat

Rocks have been found that are at least 1.7 billion years old

Salt pans are rich in Sodium and Borax

Because of the abundance of salt and lack of precipitation, the Valley is mostly devoid of plant life.

Ghost Towns

Many ghost towns in the Mojave, mostly mining towns

Oatmon, Arizona used to be a gold mining hotspot

Calico, California was a silver-mining town

Towns along Route 66 became abandoned when Route 66 was abandoned

Calico, CA

Animal Life

Desert Bighorn Sheep Mule Deer

Bobcat Coyote

Mojave Green Rattle Snake Horned Lizard

Desert Tortoise Turkey Vulture

Adaptions of Animals

Animals such as owls are nocturnal

Owls keep their mouths gaped open to evaporate water from the mouth cavity to keep cool

Many animals have light colored fur to reflect sunlight

Large ears of jackrabbits keep them cool

Desert tortoises have the capacity to hold one quart of water in their bladder

Desert tortoises spend 95% of their lives in burrows to escape the extreme temperatures

Only a few out of every hundred tortoises make it to adulthood as they are prey to animals such as coyotes, roadrunners, and gila monsters

Kangaroo rats have specialized organs that function to recoup water from their urine

Plant Life

Joshua TreeSpiny LimbsYellow and Green FlowersAverage life span 150 yearsGrow in elevations from 3,000 – 7,000 feet

Creosote Bush Waxy green leaves with yellow flowersReleases a distinct odor when it rains Average life span 100 years

Cholla The only cactus with sheaths over their spinesMost of them have orange or yellow flowers There are many varieties of cholla

Adaptations of Plants

Some plants, such as the Joshua tree, are Xerophytes

Xerophytes have few leaves in order to cut down on transpiration (loss of water vapor)

The creosote bush contains a deep tap root system and tastes bitter to discourage animals from eating it

The cholla cactus has the ability to store water and has thick spines to protect it from potential predators

Plants such as the octillo are dormant during dry periods but perform photosynthesis after rainfall

Unique Traits of Mojave Desert Life

The Joshua tree is native to the Mojave Desert and does not naturally grow anywhere else

The Mojave Rattlesnake’s venom is ten times more toxic than that of most rattlesnakes

The Mojave Rattlesnake gives live birth to its young, rather than laying eggs

Fungus is found in the desert in the form of desert varnish, which turns rocks different colors

The Timbisha Shoshone tribe of Native Americans, which have inhabited the Death Valley region of the Mojave desert for the last 1,000 years, has been forced to adapt to a modern way of life as people have moved into their native land over the past 150 years

Approximately 50-60 people from the Timbisha tribe reside in Death Valley today

Works Cited

http://mojavedesert.net/overview/a02.html

http://www.nps.gov/moja/naturescience/plants.htm

http://www.blm.gov/pgdata/etc/medialib/blm/ca/pdf/pdfs/needles_pdfs/brochures.Par.29114.File.dat/Wildlife.pdf

http://www.blueplanetbiomes.org/mojave_desert.htm