Mojave Desert

The Mojave Desert is located in the southwestern United States and is composed of Death Valley, Pahrump Valley, Amargosa Valley, the Las Vegas Valley and some of the surrounding areas.

The Mojave Desert region has oscillated in climate many times in the past. When man first arrived in the Mojave, it was not likely to be as desert like as what we experience today. While, no one is sure when man first visited the region, there is evidence for human activity over 10,000 years ago! That would have marked about the end of the Pleistocene era, a time when the

Mojave was a much cooler and less arid environment. Portions of what are now vast expanses of desert, were likely shorelines of lakes, streams and marshes, and plentiful vegetation and animal life.

As the climate became hotter and drier, the lakes dried up, the streams receded, and left behind isolated ground water fed springs that contain species found no where else in the world, or "endemic" species.

The Mojave Desert is in the North American Desert region, between the hot Sonoran and Lower Colorado deserts to the South, and the Great Basin Desert to the North. While it is very hot in the Mojave in the summer, it also has a tendency to get pretty cold and wet in the winter, which means its residents have to be able to tolerate both extremes!

In a single day in the Mojave, the climate (weather patterns for a particular region or habitat) is often very extreme, reaching hot temperatures of 50°C (120°F) and even hotter in the summer and often much cooler when the sun goes down (outside of the city - where there is no concrete or asphalt to hold the heat). In the winter, the temperature often stays below freezing at night but warms up to a comparatively comfortable temperature in the day. Because of these extremes, it is full of organisms with unique adaptations many people don't even realize exist!

The Mojave averages less than 12cm (5 inches) of precipitation (rain and snow) a year! Some places on Earth get more than that in some days!

When it does rain, the water runs off of bajadas collects in low places like this desert playa (dry lake bed) or in washes called arroyos. Some storms carry so much water the ground cannot soak it up and the land floods.

Because water is so scarce, it is the most significant factor impacting the organisms that live in the Mojave. Life as we know it can not exist without water. So how do desert organisms do it?

Though water is scarce, the Mojave is very special in that there is still quite a bit of water available. We have temporary rock pools, rivers, washes, desert plants hold water, and even the ground is an amazing water source in many areas. Join us in exploring the many creative ways organisms survive in the Mojave Desert!

We think you will find that Desert Survivors are more fun than many other organisms because they have so many challenges to face.

For example, our Mojave Desert is home to more than 200 endemic (organisms that ONLY live in a particular location on Earth, and are naturally found no where else) plant species.

There are many different kinds of deserts. Some deserts are hot, like the Sahara Desert of Northern Africa. Others are very cold like Antarctica (as seen in the pictures on the right).

The Mojave is a "hot/cold desert", meaning it is often cold in the winter and very hot in the summer. But also varies with elevation. This also means the organisms that live in the Mojave have to be able to survive both temperature extremes.

The Mojave valleys are punctuated by towering mountains ranges such as the White, Spring, and Sheep ranges. These mountains serve as islands in the desert that tremendously increase biological diversity with the Mojave Region. Some of these habitats are remnants left behind from a much cooler and wetter climatic period prior to about 10,000 years ago.

The Mojave Region became desert as large mountian ranges such as the Sierra Nevadas formed over several millions of years, imparting a rain shadow effect, meaning it is "shadowed" from precipitation by the mountains making the western side of the Sierra Nevada Mountains much more moist than the dry, or arid, east side.

During the Pleistocene glacial era, of about the last 2 million years, the Mojave region has cycled between less desert like in cooler periods with more precipitation and more desert like during warmer periods that tend to offer a more exaggerated rain shadow, and thus drier climate. Today, we are witnessing a warmer period called the Holocene, but who nows what tomorrow will bring!

Tune in to Episode One to find out what makes desert animals so special! Episode One highlights what a desert is and how the Mojave Desert was formed before the feature presentation starring the red-spotted toad.