Sea of Dunes
Nicknamed the world’s oldest desert, the Namib stretches along the coast of Namibia to form one of the most spectacular and richest deserts in the world. Gently sloping toward the Atlantic Ocean, it is patterned by a sea of giant red sand dunes, some that reach 1000 feet (305 m) high. Because of its long, stable climate over time, a number of species boast ancient origins. Others have evolved unusual adaptations to survive in the extremely harsh environment.
Although annual rainfall is limited to only .2 to 3 inches (5 to 76 mm) per year, thick fog from the Atlantic often blankets the dunes to create enough moisture for many species to survive. A tenebrionid beetle adopts a head-down position to allow condensing fog to trickle down into its mouth. Another beetle, Lepidochora discoidalis, is known to build trenches to trap fog. Even the black-backed jackal has been observed licking condensed fog off of stones. Plants have also adapted unusual features to help trap water and minimize loss. Although not typical, one of the most famous inhabitants of the Namib Desert is the welwitschia plant, which Charles Darwin described as the "platypus of the plant kingdom." With two wide undulating leaves, some believe that the plant absorbs water from fog. Yet it is often found along riverbeds, where it absorbs water with long lateral roots.
The seemingly endless sea of sand, gravel plains, and riverbeds are home to an assortment of species specially adapted to this hot and dry environment. The shovel-snouted lizard "dances" on the hot dunes by lifting its feet on the sand, while the Peringuey’s adder traverses through the dunes with a sidewinding slither. Desert lizards are extremely well adapted so that they have the lowest water-loss rates of any desert organisms. One striking species is the web-footed gecko. With a translucent body and bloodshot eyes, this gecko holds itself high on the surface of the dunes, leaving leaf-like prints with its web feet. Its predators include dancing white lady spiders, hunting spiders, and sidewinding adders. Mammals, however, have higher rates of water loss, and thus need to find other adaptations to combat the heat. Many desert rodents, such as Setzer’s hairy-footed gerbils and Grant’s golden moles, emerge at night when the air temperature cools. Along the shore of the Skeleton Coast, brown hyena and black-backed jackal have been seen foraging on fish and larger carcasses. Birds include the dune lark, Gray’s lark, and threatened lappetfaced vulture. Among strips of low-lying shrubs, pencil plants and dollar plants trap sand between the dunes and the shore. Other plants, which occur along dry watercourses include Welwitschia, camelthorn and mustard tree.
Cause for Concern
Although much of this ecoregion is protected, one of the main threats lies in current land use practices. Most of this region falls within the Sperrgebeit (Diamond Area 1) famous for its diamonds. While access is restricted to mining operations within the "forbidden territory," current prospecting practices do pose a threat to the conservation of biodiversity of this sensitive landscape.
For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.All text by World Wildlife Fund © 2001