With a land surface area of 1,2 million km2 - representing just 1% of the earth's total land surface - South Africa contains almost 10% of the world's total known bird, fish and plant species, and over 6% of the world's mammal and reptile species. This diversity is highly threatened by development, with 34% percent of South Africa's 440 terrestrial ecosystems being threatened. Of these, 5% are critically endangered (mostly in the forest and fynbos biomes), 13% are endangered (mostly in the grassland and savanna biomes), and 16% are vulnerable (mostly in the fynbos, grassland and succulent karoo biomes). The situation is even worse in aquatic systems where 82% of river types are threatened, of which 44% are critically endangered, 27% are endangered, and 11% are vulnerable. The combination of high levels of diversity and high threat results in there being three internationally recognized biodiversity hotspots in South Africa namely in Succulent Karoo, the Cape Floral Kingdom and the Maputaland Pondoland Albany Hotspot. The Succulent Karoo boasts the richest succulent flora on earth, as well as remarkable endemism in plants, with 69 percent as endemics. Reptiles also show relatively high levels of endemism in the region. It is also one of only two entirely arid ecosystems to earn hotspot status, and is home many unique species of lizards, tortoises and scorpions. Grazing, agriculture and mining, especially for diamonds and heavy metals, threaten this fragile region. Fortunately, low population levels have allowed for greater preservation in the Succulent Karoo when compared to other more densely populated regions, and allow relatively easy protected area expansion compared to other regions. The Cape Floristic Region is one of the world's five Mediterranean hotspots. Home to the greatest non-tropical concentration of higher plant species in the world, the region is the only hotspot that encompasses an entire floral kingdom, and holds five of South AfricaÔÇÖs 12 endemic plant families and 160 endemic genera. The geometric tortoise, the Cape sugar-bird, and a number of herbivore species are characteristic of the Cape Floristic hotspot. The Maputaland-Pondoland-Albany hotspot, which stretches along the east coast of southern Africa below the Great Escarpment, is an important center of plant endemism. The regionÔÇÖs warm temperate forests are home to nearly 600 tree species, the highest tree richness of any temperate forest on the planet. The rescue of the southern subspecies of white rhinoceros from extinction, which took place in this hotspot, is one of the best-known success stories in African conservation. Private nature reserves contribute significantly to the protection of Maputaland-Pondoland-Albany Hotspot, but enjoy little formal recognition or security of conservation tenure. South AfricaÔÇÖs west coast is part of the highly productive southern Benguela Large Marine Ecosystem that hosts vulnerable marine ecosystems, and breeding populations of threatened seabirds.