In the southwest of Namibia, there is a narrow strip along the coast called Sossuslei. Here you will encounter the famous giant red dunes stretching as far as the eye can see. The wind has carved wonderful contours, ridges, gullies and spines into them. Behind the dunes are flat valleys sparsely covered in grass the colour of pale yellow gold. These plains are intersected occasionally with dry creek beds, where groves of small trees add a welcome ribbon of green to the landscape. In the distance, the stark rocky hills and mountains rise up steeply from the valley floor. They make a striking contrast to the grassy plains and are dramatically coloured in hues of black, blue, red and purple to create a rich palette.
This area is in the Namib Desert and is part of the 50,000 sq km Namib Nauluft National Park. This “sand sea” was formed when the ephemeral Tsauchab River was blocked by sand and now the dunes stretch for 400 km along the coast. To the west along the coast there is a cold current that runs the length coast, bringing cooler winds and a little moisture and the escarpment that runs parallel to the coast is some 100 km inland.
Kulala Wilderness Reserve is 40,000 hectares in area and home to oryx, ostrich, springbok and some small carnivores where occasionally, cheetah and leopards can be sighted. It is a dry place with a very low rainfall of less than 4 inches or 100 mls a year. Amazingly the animals have adopted to these harsh conditions and have developed many unique and ingenious survival mechanisms.
The climate is hot and dry in summer and cold and dry in winter. What little rain there is, will make the many ephemeral rivers and creeks run and this is a boon to many animals who are near death from thirst by this time, such as the magnificent oryx. They trek each day, or every second day, to the nearest source of water which can be hours away from the grass plains where they eat what little grass is left at the end of the dry season.
The oryx are strikingly beautiful antelope and have developed some unique physiological changes to cope with the heat and lack of water. The blood that circulates from the heart to the body is then sent to their muzzle of their nose where it is cooled. This cooled blood is then circulated to their brain. Also, they do not urinate very often and have a specially adapted muscle in their anus that extracts moisture from their faeces before they defecate.
They live in herds and the newborn calves are able to run with the herd immediately after birth. Both males and females possess permanent horns and are of equal length. The horns are narrow, and straight and are lethal — the oryx has been known to kill lions with them. The horns also make the animals a prized game trophy, which has led to the near-extinction of the two northern species.
The social system of the oryx is unusual, in that non-territorial males live in mixed groups with females, or with females and their young. Groups are composed of 10 to 40 males and females of all ages and both sexes.
The dominance hierarchy among oryx is based on age and size. As they grow, calves test one another in what look like games, though in reality are tests of strength. As the hierarchy becomes established, the need to fight is reduced. Ritual displays replace actual contact, except when evenly matched individuals may have to fight to establish their rank. Along with lateral displays, oryx perform a slow, prancing walk and sometimes break into a gallop. When several males are making these displays, they may clash horns.
Herd composition in the wild constantly changes according to need. Oryx wanting to drink, for example, form a group to go to water, or females with young form a group that moves more slowly. The result is a social system that allows for individual needs but retains the advantage of group living. Oryx range widely over a large area, but their keen sense of smell alerts them to rain in the area, so that groups quickly assemble, often in herds of 200 or more, to feed on new growth.