The Karoo (probably from a Khoikhoi word meaning desert) is a semi-desert natural region of South Africa. There is no exact definition of what constitutes the Karoo, and therefore its extent, and the fauna it contains are also not precisely defined. The Karoo is partly defined by its topography, geology, and climate – above all, its low rainfall, arid air, cloudless skies, and extremes of heat and cold.
The Karoo formed an almost impenetrable barrier to the interior from Cape Town, and the early adventurers, explorers, hunters and travellers as a place of great heat, great frosts, great floods and great droughts. Today it is still a place of great heat and frosts, and an annual rainfall of between 50–250 mm, though on some of the mountains it can be 250–500 mm higher than on the plains. However, underground water is found throughout the Karoo, which can be tapped by boreholes, making permanent settlements and sheep farming possible.
The vegetation consists of aloes, mesembryanthemums, crassulas, euphorbias, stapelias, and desert ephemerals, spaced 50cm or more apart and becoming very sparse going northwards into Bushmanland and, from there, into the Kalahari Desert. The driest region of the Karoo, however, is its southwestern corner, between the Great Escarpment and the Cederberg-Skurweberg mountain ranges, called the Tankwa Karoo, which receives only 75 mm of rain annually. The eastern and north-eastern Karoo are often covered by large patches of grassland. The typical Karoo vegetation used to support large game, sometimes in vast herds. Today sheep thrive on the xerophytes, though each sheep requires about 4 hectares of grazing to sustain itself.
The Karoo is sharply divided into the Great Karoo and the Little Karoo by the Swartberg Mountain Range, which runs east-west, parallel to the southern coastline, but is separated from the sea by another east-west range called the Outeniqua –Langeberg Mountains. The Great Karoo lies to the north of the Swartberg range; the Little Karoo is to the south of it.
The ‘Succulent Karoo’ biome runs along the West Coast, from approximately Lamberts Bay northwards to over 200 km into southern Namibia. It starts in the south just north of the ‘Sandveld’ geographical region, approximately 250 km north of Cape Town, and continues through ‘Namaqualand’, the ‘Richtersveld’, immediately south of the Orange River, and on into the ‘Namaqualand’ or ‘Namaland’ region of southern Namibia. It also has a major extension inland into the ‘Tankwa Karoo’ and ‘Moordenaarskaroo’ regions of the Lower Karoo, and adjoining Upper Karoo region of the geographic Great Karoo. It also occurs to the south, in part of the Breede River Valley, as the Robertson Karoo. From here it continues eastwards into the western half of the ‘Little Karoo’. It is dominated by dwarf, leafy succulent shrubs, and annuals, predominantly Asteraceae, popularly known as ‘Namaqualand Daisies’, which put on spectacular flower displays covering vast stretches of the landscape in the southern spring-time (August–September) after good rains in the winter. Grasses are uncommon, making most the biome unsuitable for grazing. The low rainfall, in fact, discourages most forms of agriculture. An exception is the thriving ostrich farming industry.
The ‘Nama Karoo’ biome is located entirely on the central Plateau mostly at altitudes between 1000 m and 1500 m. It incorporates nearly the whole of the historical and geographical Great Karoo, but also includes a portion of southern Namibia’s Namaqualand, and South Africa’s Bushmanland. It is defined primarily by the dominance of dwarf shrubs with a co-dominance of grasses especially towards the north-east and east. The shrubs and grasses are deciduous, mainly in response to the irregular rainfall. Much of the Nama Karoo biome is used for sheep and goat farming. Overgrazing exacerbates the erosion caused by the violent thunderstorms that occur, infrequently, in the summer. It also promotes the replacement of the grasses by shrubs, especially the less edible varieties such as the threethorn Rhigozum trichotomum, bitterbos Chrysocoma ciliate and sweet thorn Acacia karroo.
The Great Karoo used to support a large variety of antelope, which have dwindled into insignificance, and, with them, the large carnivores have all but disappeared. Today the caracal, black-backed jackal, Verreaux’s Eagle and Martial Eagle are arguably the largest predators likely to be seen in the Great Karoo today. Leopards do occur, especially in the mountains, but are very secretive, and therefore rarely seen. Many of the animals that formerly inhabited the Karoo in large numbers, including lions, have been re-introduced to the area in nature reserves and game farms.
Bird-wise, the Karoo is the easiest place to find a plethora of localized endemics, many of which only occur in western South Africa and southern Namibia. Rocky outcrops and the Great Escarpment provide excellent chances at the elusive Cinnamon-breasted Warbler (which skulks in rock crevices) and the nomadic (and thus sometimes tough to pin down) Black-headed/Damara Canary duo (these two have been split in the past but are currently considered conspecific). Layard’s Tit-babbler and its much more common and widespread relative, Chestnut-vented Tit-babbler, also lurk in this rocky habitat. Pale-winged Starling fly overhead and with extreme luck Cape Eagle Owl might be located along with the more common Spotted Eagle Owl.
The escarpment and other mountains often abruptly end on vast plains, which host a completely different suite of exciting endemics, meaning that a birder new to the Karoo can see a large number of life-birds in a short space of time. Localized species of the arid plains include Karoo Chat, Sickle-winged Chat, Tractrac Chat, Karoo Long-billed Lark, Karoo Lark, the beautiful Rufous-eared Warbler, Karoo Eremomela, Burchell’s Courser, Double-banded Courser, Karoo Korhaan, Ludwig’s Bustard, Pale Chanting Goshawk, Namaqua Sandgrouse and many others.
Dry riverbeds which are lined with “Acacia karoo” (now Vachellia karoo thanks to the controversial name change of this iconic African tree genus) are inhabited by yet another mix of exciting southern African endemics such as Pririt Batis, Fairy Flycatcher, Southern Grey Tit and various canaries. The uncommon Namaqua Warbler inhabits a very unique habitat within the Karoo where Acacia/Vachellia trees meet Phragmites reeds (which means permanent water, of course not common in the Karoo).
The Northern Karoo area known as “Bushmanland” boasts a couple of even more localized endemics. Red Lark is found only in this area and can only be found in one province of South Africa, the Northern Cape. Sclater’s Lark and Black-eared Sparrowlark are also best sought here although their ranges do extend into southern Namibia as well. This is the only area for Stark’s Lark in South Africa, but many birders find this species in Namibia. When in Bushmanland, many birders also go to the edge of the Namib along the west coast just south of the Namibian border for Barlow’s Lark.
While serious birders need to visit the Northern Cape/Bushmanland area of the Karoo, most of the Karoo’s special birds can be found within 2.5 hours from Cape Town in the Tanqua Karoo, or in the Little Karoo and Karoo National Park, both of which are easy to access from the Garden Route/George/Knysna area. Usually one can find many of the fynbos endemics while crossing the mountains (which form a rainshadow) from the coast to the Karoo. This means that given a couple of days, one can “clean up” on many of the Karoo and fynbos specials.
There are also many other impressive birds that are certainly not restricted to the Karoo but which are commonly found there. These include superb raptors such as Martial Eagle (Africa’s largest eagle), Booted Eagle and South Africa’s national bird, Blue Crane.
Text Source: Fatbirder
Photo Source: Birding Ecotours
Map Source: Google Maps