Libya Photograph by SaharaMet   Northern Africa Deserts and Xeric Shrublands   1,791,500 square miles (4,639,900 square kilometers) -- about thrice the size of Alaska Vulnerable

· Immense Sand Dunes and Swirling Winds
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Immense Sand Dunes and Swirling Winds

The Sahara Desert is a vast expanse of searing heat and merciless winds that stretches from the Atlantic Ocean to the Red Sea. This ecoregion covers the central part of the desert, where the monotony of vast sand dunes is occasionally broken by areas of stone plateaus, gravel plains, dry valleys, salt flats, and high mountains with snowcapped peaks. To survive in this harshest of ecoregions, plants must have special adaptations to help them cope with extreme temperatures and drought. Many of the plants here are ephemeral, with short life cycles that are lived out only after rain. Other plants that can live here year-round, such as those in the genus Euphorbia, are able to take in water when it does rain and then store it for future use.

Special Features

All living things in the Sahara Desert must deal with extremes in the dry and hot climate. Rainfall is always low here, but it can be extremely variable from year to year and place to place. For example, one small area may receive a downpour that lasts for several hours, while the land stays completely parched just a few miles away. And while the Sahara is unbearably hot during the day, the temperatures can cool off dramatically at night. Winds are another natural force to reckon with in this ecoregion. Dust-laden gales and whirlwinds can disperse or even destroy small plants and animals. One of the rare havens for plants and animals in this harsh environment comes from vast underground aquifers running beneath the desert, which occasionally surface to form small, watery oases.

	One of the more interesting species in this ecoregion is the scarab beetle. Female scarab beetles deposit their eggs in balls of dung. The ancient Egyptians, who were not aware of this fact, would marvel at the seemingly spontaneous appearance of newborn scarab beetles. These insects feature prominently in ancient Egyptian mythology as being associated with new life and rebirth.

Wild Side

With wingspans of four feet, desert eagle owls soar above the vast Sahara Desert. Down on the ground, large brown and white birds called Houbara bustards are well-camouflaged among the sand and boulders as they search for small rodents and lizards. When they take flight, their black and white tail patterns are striking against the open desert sky. In the sands below, bright, iridescent scarab beetles spend their days harvesting dung from animals such as dama gazelles. Scimitar-horned oryxes, with their long, curved horns gleaming in the sunlight, search for clumps of grass. Antelopes called addaxes display some of the best examples of adaptations to desert life: large, flat hooves that enable them to walk over the sand without sinking, high tolerance for dehydration and extreme temperatures, and an ability to find shelter in depressions that they dig in the sand.

Cause for Concern

Because of the harshness of this environment, the Sahara is largely undisturbed. The most degradation here is found in areas where there is water, such as aquifer oases or along the desert margins where some rain usually falls most years. In these areas, animals such as addaxes, scimitar-horned oryxes, and bustards are over-hunted for their meat.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.