CONSERVATION STATUS OF THE SOUTH-AFRICAN ENDEMIC AVIFAUNA

The abundance (= number of individuals) of populations of avian species endemic to the South African geographical region was estimated both inside and outside the region's nature-reserve system. The southwestern part of the region contains the greater proportion of the 33 endemic and 11 near-endemic (at least 90% of a species' range or population occurring within the region) species. Nearly all these species are represented by breeding populations in established nature reserves. However, the nature-reserve populations of 24 (55%) of the 44 species are relatively small (< 1 000 individuals each) and are fragmented further into semi-isolated subpopulations. The species with the smallest (< 500 individuals each) total populations breeding in nature reserves are essentially inhabitants of either the region's Karoo or grassland biomes or both. None of the species has a total breeding population smaller than 500 birds, and only in the black harrier Circus maurus is the total breeding population unlikely to exceed 1 500 individuals. Apart from this species, there are substantial (> 1 500 individuals per species) breeding populations of all of the South African endemic and near-endemic birds. The priority for preserving viable populations of the more vulnerable species (in terms of their relatively small breeding populations) is clearly vested in the creation of several new and large nature reserves in the region's Karoo and grassland biomes.