LIE OF THE LAND
High ground extends over about half of Namibia. The only part of the country that is predominantly rocky, with the great majority of its mountains and hills, it forms a bold divide between the Namib Desert and the Kalahari Basin. It consists of an irregular plateau with a mountainous escarpment on its western edge that descends steeply to the desert floor.
The Great Escarpment is highest and steepest in its southern half and in its northernmost quarter. Mountains rise end-to-end, southward from the Gamsberg to the Naukluft range and beyond, to form the southern escarpment, while in the north the Otjihipa Mountains dominate a shorter section, remote and hard to reach.
Between the two tracts of mountainland, erosion has reduced the escarpment to a peneplain where inselbergs stand alone, like islands on the degraded plateau. The largest one in terms of bulk is the Erongo south-west of Omaruru.
The opposite side of the plateau in the east slopes evenly down to the Kalahari except in a few places where lone mountains like the Waterberg protrude from it.
The plateau runs almost the full length of Namibia. It is a mosaic of lesser plateaux (one of them a lava field), mountains, hills, plains, basins and incised rivercourses. Its landforms range from granite, basalt and limestone massifs to a canyon on the Fish River, near its confluence with the Orange, that plunges half a kilometre into the Huib High Plateau.
The highlands form a watershed that is mostly dormant. The ephemeral rivers that flow into the Namib and Kalahari all rise there, but for most of the year they are empty and dry, their sandy beds white against the dark rock all around.
The majority of inland towns are located in or beside the highlands. They are generally small and far apart, with uncultivated land between them, fenced and stocked with cattle in the north and sheep in the south. The main towns are Otjiwarongo and Tsumeb north of Windhoek and, to the south, Mariental and Keetmanshoop.
In terms of physical infrastructure, such as roads and powerlines, the highlands are the most developed part of Namibia, with the exception of the far north-west where large tracts of the Kaokoveld, especially its western reaches, are almost empty and in essence still wilderness.
Plant growth dwindles along with the rainfall from north to south and from east to west. Where vegetation is otherwise scant because of low rainfall, trees and shrubs dot drainage lines, or form narrow stands along ephemeral rivers.
North of Windhoek and south of it as far as Rehoboth, the highlands lie within the Savannah Biome where woody trees and shrubs -- fine-leaved acacias -- share dominance with perennial grasses. The biggest trees are the camel thorn (Acacia erioloba), sweet thorn (A. karroo) and umbrella thorn (A. tortilis).
Two acacias are endemic to parts of Namibia, the Brandberg (A. montis-usti) to the Brandberg area and the whip-stick (A. robynsiana) to the Kaokoveld, while the mountain thorn (A. hereroensis) mainly grows, within Namibia, in the Khomas Hochland and on the mountains around Windhoek.
Isolated woodlands with broad-leaved trees and shrubs intrude in the Waterberg and the Otavi Mountains.
The southern highlands beyond Rehoboth form part of the Nama Karoo Biome where dwarf shrubs and stubbly grasses together are dominant. Apart from quiver trees in rocky habitats, trees grow only along rivercourses. With annual rainfall of less than 250 mm and torrid summers, the Nama Karoo in Namibia is arid and intrinsically a desert.
The escarpment is classified as an extension of the Nama Karoo, but it also supports distinctive if sparsely distributed trees and shrubs, among them fat-trunked commiphoras, cactus-like euphorbias and quiver trees.
North of Windhoek
The basalt-and-granite Erongo massif is an extinct volcano that rises 1 200m above a vast peneplain some 200km north-west of Windhoek as the crow flies. Its central feature is the eroded core of a caldera or volcanic crater that caved in under the weight of lava.
With a diameter of 35km and a height of 2 329m above sea level, Erongo is the largest but not the highest of the circular inselbergs, known as ring complexes, that are scattered across Namibia between Cape Cross and Grootfontein. Only the Brandberg is higher.
The massif lies in a triangle between the villages of Omaruru, Karibib and Usakos where desert lands edge into thorn-bush savannah. The peneplain is what remains of the Great Escarpment in this part of the country after deep erosion over millions of years. It is part of an extensive gap in the escarpment between the Kuiseb and Huab rivercourses.
Erongo is considered to be an endemic hotspot for plants, reptiles, birds and small mammals. In addition its granite surfaces hold numerous prehistoric paintings.
The massif largely falls within the Erongo Mountain Nature Conservancy, an association of 30 private landowners, dedicated to the protection of the ecosystem over an area of 200 000ha. One of its aims is to reintroduce locally extinct species such as black-faced impala and black rhinoceros.
Named for its numerous springs and streams, the flat-topped Waterberg supports broad-leafed woodlands in contrast to the thorn-tree savannah on the adjacent plains, some 1 800m below its mesa-like cliffs. Leafy trails run through the woods and up the mountainside to the plateau on top.
A small colony of Cape vultures (Gyps coprotheres) breeds in the Waterberg. Once common throughout southern Africa, the Cape vulture is now an endangered species, mostly found along the eastern escarpment of the subcontinent. The population in the Waterberg is isolated from the rest. It is the second largest vulture in Africa, with a wingspan of nearly 3m.
The plateau is a sanctuary for rare and endangered wildlife. Visitors are taken in open vehicles to view large antelope such as roan (Hippotragus equinus), sable (H. niger) and tsessebe (Damaliscus lunatus) as well as African buffalo (Syncerus caffer), introduced from northeast Namibia where they normally occur. Squarelipped or white rhinoceros (Ceratotherium simum), once extinct in Namibia and reintroduced from South Africa, also range on the plateau.
Situated east of Otjiwarongo, the Waterberg is 274km north of Windhoek along routes B1, C22 and D2512. The facilities include a restaurant and a swimming pool.
South of Windhoek
The biggest dam in Namibia, 25km² in extent when full, is set in a game park near the town of Mariental, some 260km south of Windhoek on route B1. Black rhinoceros (Diceros bicornis bicornis), gemsbok, kudu, Hartmann's mountain zebra, red hartebeest (Alcelaphus buselaphus) and springbok are found in dwarf-shrub savannah around the dam.
The water attracts reed cormorants (Phalocrocorax africanus), whitebreasted cormorants (P. carbo), African darters (Anhinga rufa), African fish eagles (Haliaeetus vocifer), greater flamingos (Phoenicopterus ruber), pinkbacked pelicans (Pelecanus rufescens), eastern white pelicans (P. onocrotalus) and African spoonbills (Platalea alba).
The facilities include a restaurant, a swimming pool and hiking trails.
High above the desert wastes in the Great Escarpment, splinters of a lost paradise remain in ravines and valleys with clear-water springs, streams, waterfalls and rock pools, where trees and shrubs form green thickets.
Built of enormous sheets of limestone and dolomite, the Naukluft mountains hold water below ground in aquifers, hollowed out over the ages as rainwater seeped through rock.
The massif is partly on private land and partly in a national park with demarcated trails for hikers and 4x4s. It is situated on the edge of the Namib some 240 km south-west of Windhoek. Follow routes B1, C24 and D1206.
FISH RIVER CANYON
Near the end of its 600 km course from the central highlands to the Orange River, the Fish River meanders through a canyon that is one of the natural wonders of Africa, reputedly the second largest in the world after the Grand Canyon in Arizona.
Geologically the Fish River Canyon actually consists of two canyons that are joined together, one deeper and the other wider, with a combined length of 56km as measured along the rivercourse. The lower (or southern) canyon is 460-550m deep and 5km wide, while the upper one is 160-190m deep and 8km wide.
"The edge ... is reached with startling suddenness," writes T.V. Bulpin in his Illustrated Guide to Southern Africa (1978, Reader's Digest, Cape Town). "There is absolutely nothing to warn of the scenic drama ahead and the unwary could step straight into eternity."
Some 300 million years ago a proto-canyon formed in a rift valley about 300m above the present-day level of the river. Glacial and water erosion widened the canyon, but did little to deepen it over the next 170 million years, until crustal uplift in southern Africa sharply increased the gradient of the river. What had been a slow river became a swift one that carved out the deep meanders that now characterise the canyon.
The Fish River rises west of Maltahöhe. It flows north for a short distance, does a U-turn and thereafter, for the rest of its course, flows south. Although the river is ephemeral and the Hardap Dam checks its flow in the rainy season, pools in the canyon hold water throughout the year and hot-water springs bubble out of faults in the rock formation.
The canyon consists mostly of bare rock, except along the sandy rivercourse and in the ravines, where hardy vegetation grows. It lies in a desert landscape at the interface between the Nama Karoo and Succulent Karoo biomes.
Wildlife is elusive in the canyon, but includes Hartmann's mountain zebra, klipspringer (Oreotragus oreotragus tyleri), kudu, rock dassie (Procavia capensis) and chacma baboon. The plains around the canyon support species such as gemsbok and springbok.
Backpackers come from around the world to hike in the Fish River Canyon. It is located some 600 km south of Windhoek. Follow routes B1 to Keetmanshoop, B4 to Seeheim and finally C12 to the canyon.
ELEPHANT IN THE DESERT
In habitats with sufficient vegetation and water an adult elephant consumes as much as 300kg of roughage and 230 litres of water every day of its life. Consider what a herd of them would eat and drink in a week or a month. Or a year.
African elephant in a desert? Well, yes. Not only elephant, but other large mammals as well, like black rhinoceros and giraffe. Their ranges extend into the northern Namib from river catchments in the Kaokoveld. Apart from the Kunene River, seven rivercourses northwards from the Ugab provide them with possible routes across the desert, right to the Skeleton Coast. The biggest are the Hoarusib, the Hoanib, the Huab and the Ugab.
Large mammals find shelter and sustenance in the sparse growth along ephemeral rivers. If it were not for trees and bushes in the socalled "linear oases", along with patches of grass on the desert plains after rain, they would certainly starve to death.
As they move between rivercourses, from one spring or seep to another, they venture into waterless desert and even dune fields. Hence their identification as "desert", "desert-dwelling" or "desert-adapted" animals. None of them is a species or subspecies on its own, but rather an ecotype, behaviourally adapted to marginal conditions.
One elephant population dwells permanently in the inner Namib between the Huab and Kunene rivers. They hardly ever venture out of their home range.
Desert-adapted elephant in the Kaokoveld and the Namib walk further for water and fodder than any other elephant in Africa. The distances between waterholes and feeding grounds are as great as 68km. The typical home range of a family herd is larger than 2 000km² or eight times as big as ranges in central Africa where rainfall is much higher.
With little water available in the riverbeds, elephant on occasion drink only every fourth day, partly to avoid forced treks to fresh sources. When surface water is unavailable they dig waterholes that serve as lifelines for other animals as well.
Scientific observations show that desertadapted elephant also forage with care, unlike their destructive and wasteful kin in bush and woodlands. They seldom fell trees and instead tend to browse on regrowth from previously damaged ones.
They debark trees to a lesser extent than elephant elsewhere. Overall they kill fewer trees, in a ratio of 1:7, than factors such as drought and fire.
Where elephant congregate, their dung helps future growth. It enriches the soil and adds to the litter mass in the ephemeral rivercourses where camel-thorn and ana seeds in particular are most likely to germinate.
3m (record 4m); cows 2,5 m.
They like it thorns and all
Namibia is home to the larger of two subspecies of black rhinoceros found in southern Africa. The only population that remains in the wild, unfenced and outside reserves, occupies an arid range in the western Kaokoveld.
Their preferred habitat is the mountainous escarpment, but they follow ephemeral rivers into the northern Namib as well, especially when conditions are favourable after rains. They are the only black rhinoceros in Africa that are internationally recognised as a "desert group".
Like desert-adapted elephant, they cover great distances. They walk and feed at night and rest during the day. To meet their nutritional and bulk requirements they browse on no fewer than 74 of the 103 plant species that grow in their range.
One of the few animals to eat fibrous welwitschia leaves, they even feed heavily on the milkbush (Euphorbia virosa) with its sharp spines and toxic latex, presumably because of the high water and fat content. They are able to overcome the formidable chemical and physical defences of dryland plants without apparent harm.
Good numbers of black rhinoceros are also found in the Etosha National Park. The total population in Namibia is the second largest in southern Africa. Once widespread in the subcontinent, black rhinoceros are an endangered species. The smaller subspecies, Diceros bicornis minor, does not range into Namibia.
The Kaokoveld .....