Ngorongoro Crater

The Ngorongoro Conservation Area covers 2286 sq km and encompasses the volcanic area around the Ngorongoro Crater – including the still active volcano of Oldonyo Lengai and the famous Olduvai Gorge. Its centerpiece, the Ngorongoro Crater, is the largest unbroken caldera in the world and the first sight of it is breathtaking. The floor of the crater is only 100 sq miles but is home to around 30,000 animals with a high concentration of predators. The crater supports up to 25,000 large mammals. Grazers dominate: zebra, wildebeest – accounting for almost half the animals – gazelle, buffalo, eland, hartebeest and wart hog. Giraffe, for example, stay away because there is insufficient food at tree level; topi because they compete directly with wildebeest. An odd feature of the crater elephants is that they are almost exclusively bulls. Breeding herds – comprising large numbers of females and young with a few attendant older males – are probably unable to find sufficient quality food in the crater. Ngorongoro has carnivores in quantity, drawn by the large herds of prey animals. It has the densest population of large predators, mainly lion – about 100 – and more than 400 spotted hyena, living in eight clans of up to eighty individuals. Both lions and hyenas will scavenge from each other, depending on weight of numbers and of course, hunger. Most of the bird wildlife in Ngorongoro is seasonal. Also influencing the variety of bird species on display is the ratio of soda water to fresh water – soda water has the largest expanse of water on the crater floor, Lake Magadi. The lake is alkaline due to deposits of volcanic ash thrown out by surrounding volcanoes. The Empakaai Crater (2º55′ S, 35º50′ E, 2,400 m a.s.l) lies within the Ngorongoro Conservation Area in northern semiarid Tanzania. The caldera is about 35 km2, with the rim ranging from 2,700 to 3,500 m a.s.l. An 80-m deep alkaline lake, Emakat, partly occupies the caldera floor. The vegetation in the highlands (2300-3100 m a.s.l) consists of a mixture of dry evergreen forest with Juniperus procera, Tecla simplicifolia and Nuxia congesta and highland shrubs and grassland. Small patches of moist evergreen forest with Hagenia abyssinica are limited to the southern part of the caldera. Above the forest afroalpine Artemisia moorland can be found. The eastern slopes receive about 1000 mm/yr. Rainfall varies considerably due to orographic effect with a significant year to year variation. Hagenia abyssinica, a component of moist evergreen forest, being the most dominant taxa of the pollen sum, this is due to the humid condition.