The five major ridges in our area is the Magaliesberg, Roodepoort, Bronberg, Klipriviersberg and the Suikerbosrand ridges.
A wide variety of bird groups utilize ridges, koppies and hills for feeding, roosting and breeding. These groups include some owls, flacons, nightjars, swifts, swallows, martins, larks, chats, thrushes, cisticolas, pipits, shrikes, starlings, sunbirds, firefinches, waxbills, buntings, canaries, eagles and vultures. It also provides important habitat for sensitive species such as bats (roosting sites) and the rock elephant shrew. Hills and koppies generally have more insects that the immediate surroundings. If ridges are allowed to become developed in Gauteng, this will have serious implications for the future survival of many invertebrate species, many of which provide essential pollinator services such as the honey bee, certain butterflies and the dragon fly. A rare species of scorpion is apparently confines to some of these ridges.
The conservation of ridges in Gauteng will provide habitat for significantly high numbers of species allowing for their continued survival in a rapidly urbanizing province, a desirable long-term conservation goal. The ridges of Gauteng form vital habitat for many threatened of Red Data plant species. Sixty-five percent of Red Data plant species have been recorded growing on ridges in the province, while 42% of Red Data plant species are confined solely to these habitat type. Furthermore, it should be emphasized that 71% of Gauteng’s endemic plant species, i.e. plant species that occur nowhere else in the world, have been recorded on these ridges.
Many of the latter plant species are critically endangered or endangered, the highest categories of threat to which species can be assigned. These Gauteng endemics are predominantly threatened by habitat transformation and fragmentation and the accompanying resulting decline in habitat quality, all brought on by urbanization of “prime real estate properties” that the ridge environment offers.
Ridges may have a direct effect on temperature / radiation, surface airflow / wind, humidity and soil types. Ridges also influence fire in the landscape, offering protection for those species that can be described as “fire-avoiders”. The protection of the ridges in Gauteng in a natural state will thus ensure the normal functioning of ecosystem processes. In contrast, development of a ridge will alter these major landscape processes. For example, water runoff into streams and wetlands will increase.
The Klipriviersberg is virtually the only ridge system left somewhat intact in Johannesburg. A highly sensitive habitat for at least two Gauteng plant endemics, one of which is only found predominantly on the Klipriversberg, it is absolutely essential that all efforts are made to prevent any further transformation of this last remaining ridge in Johannesburg. The Gauteng ridges, together with the Drakensberg escarpment, should be regarded as one of the most important natural assets in the entire region of the northern provinces of South Africa.
Ciarra
