Ngorongoro Conservation Area
Encyclopedia
The Ngorongoro Conservation Area (NCA) is a conservation area
Conservation area
A conservation areas is a tract of land that has been awarded protected status in order to ensure that natural features, cultural heritage or biota are safeguarded...

  and a UNESCO World Heritage Site situated 180 km (111.8 mi) west of Arusha
Arusha
Arusha is a city in northern Tanzania. It is the capital of the Arusha Region, which claims a population of 1,288,088, including 281,608 for the Arusha District . Arusha is surrounded by some of Africa's most famous landscapes and national parks...

 in the Crater Highlands
Crater Highlands
The Crater Highlands are a region along the East African Rift in Tanzania, located in a spreading zone at the intersection of branches of the African and Somali tectonic plates, resulting in distinctive and prominent landforms....

 area of Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

. The conservation area is administered by the Ngorongoro Conservation Area Authority, an arm of the Tanzanian government, and its boundaries follow the boundary of the Ngorongoro Division of Ngorongoro District
Ngorongoro District
Ngorongoro District is one of the five districts of the Arusha Region of Tanzania. It is bordered to the north by Kenya, to the east by the Monduli District, to the south by the Karatu District and to the west by the Mara Region....

. The Ngorongoro Crater, a large volcanic caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

, lies within the area.

History and geography

Based on fossil evidence found at the Olduvai Gorge
Olduvai Gorge
The Olduvai Gorge is a steep-sided ravine in the Great Rift Valley that stretches through eastern Africa. It is in the eastern Serengeti Plains in northern Tanzania and is about long. It is located 45 km from the Laetoli archaeological site...

, it is known that various hominid species have occupied the area for 3 million years.
Hunter-gatherers were replaced by pastoralists a few thousand years ago. The Mbulu
Mbulu
Mbulu is one of the 5 districts of the Manyara Region of Tanzania. It is bordered to the North by the Arusha Region and Lake Eyasi, to the East by the Babati Region, to the South by the Hanang District and to the West by the Singida Region....

 came to the area about 2,000 years ago, and were joined by the Datooga around the year 1700. Both groups were driven from the area by the Maasai in the 1800s.
Massive fig trees in the northwest of the Lerai Forest are sacred to the Maasai and Datooga people. Some of them may have been planted on the grave of a Datago leader who died in battle with the Maasai around 1840.

No Europeans are known to have set foot in the crater until 1892, when it was visited by Dr. Oscar Baumann
Oscar Baumann
Oscar Baumann was an Austrian cartographer with a keen interest in ethnography.He attended classes on natural history and geography at the University of Vienna, and in 1885 was part of an Austrian exploratory expedition of the Congo Basin headed by Oskar Lenz. However, he had to leave the...

. Two German brothers farmed in the crater until the outbreak of World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

, after leasing the land from the administration of German East Africa
German East Africa
German East Africa was a German colony in East Africa, which included what are now :Burundi, :Rwanda and Tanganyika . Its area was , nearly three times the size of Germany today....

. Dr. Baumann shot three rhinos while camped in the crater, and the German brothers regularly organized shooting parties to entertain their German friends. They also attempted to drive the wildebeest herds out of the crater.

The Ngorongoro area originally was part of the Serengeti National Park
Serengeti National Park
The Serengeti National Park is a large national park in Serengeti area, Tanzania. It is most famous for its annual migration of over one and a half million white bearded wildebeest and 250,000 zebra...

 when it was created by the British in 1951. Maasai continued to live in the newly created park until 1959, when repeated conflicts with park authorities over land use led the British to evict them to the newly declared Ngorongoro Conservation Area.

The Ngorongoro Conservation Area Authority is the governing body regulating use and access to the NCA. The area became a UNESCO
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations...

 World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

 in 1979.

Land in the conservation area is multi-use: it is unique in Tanzania as the only conservation area providing protection status for wildlife whilst allowing human habitation. Land use is controlled to prevent negative effects on the wildlife population. For example, cultivation is prohibited at all but subsistence levels.

The area is part of the Serengeti
Serengeti
The Serengeti ecosystem is a geographical region in Africa. It is located in north Tanzania and extends to south-western Kenya between latitudes 1 and 3 S and longitudes 34 and 36 E. It spans some ....

 ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....

, and to the north-west, it adjoins the Serengeti National Park
Serengeti National Park
The Serengeti National Park is a large national park in Serengeti area, Tanzania. It is most famous for its annual migration of over one and a half million white bearded wildebeest and 250,000 zebra...

 and is contiguous with the southern Serengeti plains, these plains also extend to the north into unprotected Loliondo division and are kept open to wildlife through trans-human pastoralism practiced by Maasai. The south and west of the area are volcanic highlands, including the famous Ngorongoro Crater and the lesser known Empakai. The southern and eastern boundaries are approximately defined by the rim of the Great Rift Valley
Great Rift Valley
The Great Rift Valley is a name given in the late 19th century by British explorer John Walter Gregory to the continuous geographic trench, approximately in length, that runs from northern Syria in Southwest Asia to central Mozambique in South East Africa...

 wall, which also prevents animal migration in these directions.

The annual ungulate
Ungulate
Ungulates are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. They make up several orders of mammals, of which six to eight survive...

 migration passes through the NCA, with wildebeest
Wildebeest
The wildebeest , also called the gnu is an antelope of the genus Connochaetes. It is a hooved mammal...

 and zebra
Zebra
Zebras are several species of African equids united by their distinctive black and white stripes. Their stripes come in different patterns unique to each individual. They are generally social animals that live in small harems to large herds...

 moving south into the area in December and moving north in June. This movement changes seasonally with the rains, but the migration will traverse almost the entire plains in search of food. The NCA has a healthy resident population of most species of wildlife, in particular the Ndutu Lake area to the west has strong cheetah
Cheetah
The cheetah is a large-sized feline inhabiting most of Africa and parts of the Middle East. The cheetah is the only extant member of the genus Acinonyx, most notable for modifications in the species' paws...

 and lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

 populations.

Wildlife

A population of approximately 25,000 large animals, largely ungulate
Ungulate
Ungulates are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. They make up several orders of mammals, of which six to eight survive...

s along with reputedly the highest density of mammalian predators in Africa, lives in the crater. Large animals in the crater include the black rhinoceros
Black Rhinoceros
The Black Rhinoceros or Hook-lipped Rhinoceros , is a species of rhinoceros, native to the eastern and central areas of Africa including Kenya, Tanzania, Cameroon, South Africa, Namibia, Zimbabwe, and Angola...

, the local population of which declined from about 108 in 1964-66 to between 11-14 in 1995, and the hippopotamus
Hippopotamus
The hippopotamus , or hippo, from the ancient Greek for "river horse" , is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae After the elephant and rhinoceros, the hippopotamus is the third largest land mammal and the heaviest...

, which is very uncommon in the area. There also are many other ungulates: the wildebeest
Blue Wildebeest
The Blue Wildebeest , also called the Common Wildebeest, is a large antelope and one of two species of wildebeest. It grows to 115–145 cm shoulder height and attains a body mass of 168–274 kg. They range the open plains, bushveld and dry woodlands of Southern and East Africa, living for...

 (7,000 estimated in 1994), the zebra
Zebra
Zebras are several species of African equids united by their distinctive black and white stripes. Their stripes come in different patterns unique to each individual. They are generally social animals that live in small harems to large herds...

 (4,000), the eland
Common Eland
The common eland , also known as the southern eland or eland antelope, is a savannah and plains antelope found in East and Southern Africa. It is the largest antelope in the African continent...

, and Grant's and Thompson's gazelle
Gazelle
A gazelle is any of many antelope species in the genus Gazella, or formerly considered to belong to it. Six species are included in two genera, Eudorcas and Nanger, which were formerly considered subgenera...

s (3,000).

The crater has the densest known population of lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

s, numbering 62 in 2001. On the crater rim are leopard
Leopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...

s, elephant
Elephant
Elephants are large land mammals in two extant genera of the family Elephantidae: Elephas and Loxodonta, with the third genus Mammuthus extinct...

s - numbering 42 in 1987 but only 29 in 1992 - mountain reedbuck
Mountain Reedbuck
The Mountain Reedbuck is an antelope found in mountainous areas of much of Sub-Saharan Africa.The Mountain Reedbuck averages 75 cm at the shoulder, and weighs around 30 kg. It has a grey coat with a white underbelly and reddish-brown head and shoulders...

, and buffalo (4,000 in 1994).

However, since the 1980s the crater's wildebeest population has fallen by a quarter to about 19,000 and the numbers of eland and Thomson's gazelle also have declined while the buffalo population has increased greatly, probably due to the long prevention of fire which favors high-fibrous grasses over shorter, less fibrous types.

In summer, enormous numbers of Serengeti migrants pass through the plains of the reserve, including 1.7 million wildebeest, 260,000 zebra, and 470,000 gazelles. Waterbuck
Waterbuck
The Waterbuck is a large antelope found widely in Sub-Saharan Africa.Waterbuck stand at the shoulder. Males weigh and females . Their coats are reddish brown in colour and become progressively darker with age; they have a white 'bib' under their throats and white on their rumps...

 occur mainly near Lerai Forest; serval
Serval
The serval , Leptailurus serval or Caracal serval, known in Afrikaans as Tierboskat, "tiger-forest-cat", is a medium-sized African wild cat. DNA studies have shown that the serval is closely related to the African golden cat and the caracal...

s occur widely in the crater and on the plains to the west. Common in the reserve are lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

s, hartebeest
Hartebeest
The hartebeest is a grassland antelope found in West Africa, East Africa and Southern Africa. It is one of the three species classified in the genus Alcelaphus....

, spotted hyena
Spotted Hyena
The spotted hyena also known as laughing hyena, is a carnivorous mammal of the family Hyaenidae, of which it is the largest extant member. Though the species' prehistoric range included Eurasia extending from Atlantic Europe to China, it now only occurs in all of Africa south of the Sahara save...

s and jackal
Jackal
Although the word jackal has been historically used to refer to many small- to medium-sized species of the wolf genus of mammals, Canis, today it most properly and commonly refers to three species: the black-backed jackal and the side-striped jackal of sub-Saharan Africa, and the golden jackal of...

s. Cheetah
Cheetah
The cheetah is a large-sized feline inhabiting most of Africa and parts of the Middle East. The cheetah is the only extant member of the genus Acinonyx, most notable for modifications in the species' paws...

s, although common in the reserve, are scarce in the crater itself. The African Wild Dog
African Wild Dog
Lycaon pictus is a large canid found only in Africa, especially in savannas and lightly wooded areas. It is variously called the African wild dog, African hunting dog, Cape hunting dog, painted dog, painted wolf, painted hunting dog, spotted dog, or ornate wolf...

 has recently disappeared from the crater and may have declined elsewhere in the Conservation Area as well, as well as throughout Tanzania according to C. Michael Hogan.

Ngorongoro Crater

The main feature of the NCA is the Ngorongoro Crater, a large, unbroken, unflooded volcanic caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

. The crater, which formed when a giant volcano exploded and collapsed on itself some two to three million years ago, is 610 m (2,001.3 ft) deep and its floor covers 260 km² (100.4 sq mi). Estimates of the height of the original volcano range from fifteen to nineteen thousand feet (4500 to 5800 metres) high.

Although thought of as "a natural enclosure" for a very wide variety of wildlife, up to 20% or more of the wildebeest (Connochaetes taurinus) and half the zebra (Equus burchelli) populations vacate the Crater in the wet season. However, a side effect of this enclosure is that the population of Ngorongoro lions is significantly inbred, with many genetic problems passed from generation to generation. This is due to the very small amount of new bloodlines that enter the local gene pool, as very few migrating male lions enter the crater from the outside. Those who do enter the crater are often prevented from contributing to the gene pool by the crater's male lions, who, because of their large size (the result of an abundant and constant food source), easily expel any outside competitors. Animal populations in the crater include most of the species found in East Africa
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...

, but there are no impala
Impala
An impala is a medium-sized African antelope. The name impala comes from the Zulu language meaning "gazelle"...

s (Aepyceros melampus), topi
Topi
The Tsessebe , is one of five subspecies in the binomial class D. lunatus. The other subspecies include Korrigum , Tiang , Coastal Topi , and Topi . Tesessebe are found primarily in Zambia, Namibia, Botswana, Zimbabwe, and South Africa...

s (Damaliscus lunatus), oribi
Oribi
Oribi are graceful slender-legged, long-necked small antelope found in grassland almost throughout Sub-Saharan Africa.-Description:...

s (Ourebia oribi), giraffe
Giraffe
The giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...

s (Giraffa camelopardalis), or crocodile
Crocodile
A crocodile is any species belonging to the family Crocodylidae . The term can also be used more loosely to include all extant members of the order Crocodilia: i.e...

s (Crocodylus niloticus).

The crater highlands on the side facing the easterly trade winds receives 800–1200 mm of rain a year and is covered largely in montane
Montane
In biogeography, montane is the highland area located below the subalpine zone. Montane regions generally have cooler temperatures and often have higher rainfall than the adjacent lowland regions, and are frequently home to distinct communities of plants and animals.The term "montane" means "of the...

 forest, while the less-steep west wall receives only 400–600 mm; this side is grassland and bushland dotted with Euphorbia bussei trees. The crater floor is mostly open grassland with two small wooded areas dominated by Acacia xanthophloea
Acacia xanthophloea
Acacia xanthophloea is a tree in the Fabaceae family and is commonly known in English as the Fever Tree . This species of Acacia is native to eastern and southern Africa. It can be found in Botswana, Kenya, Malawi, Mozambique, Somalia, South Africa, Swaziland, Tanzania, Zambia and Zimbabwe...

.

The Munge Stream drains Olmoti Crater to the north, and is the main water source draining into the seasonal salt lake
Salt lake
A salt lake or saline lake is a landlocked body of water which has a concentration of salts and other dissolved minerals significantly higher than most lakes . In some cases, salt lakes have a higher concentration of salt than sea water, but such lakes would also be termed hypersaline lakes...

 in the center of the crater. This lake is known by two names: Makat as the Maasai called it, meaning salt; and Magadi. The Lerai Stream drains the humid forests to the south of the Crater, and it feeds the Lerai Forest on the crater floor - when there is enough rain, the Lerai drains into Lake Magadi as well. Extraction of water by lodges and NCA headquarters reduces the amount of water entering Lerai by around 25%.

The other major water source in the crater is the Ngoitokitok Spring, near the eastern crater wall. There is a picnic site here open to tourists and a huge swamp fed by the spring, and the area is inhabited by hippopotamus, elephants, lions, and many others. Many other small springs can be found around the crater's floor, and these are important water supplies for the animals and local Masaai, especially during times of drought.

Aside from herds of zebra
Zebra
Zebras are several species of African equids united by their distinctive black and white stripes. Their stripes come in different patterns unique to each individual. They are generally social animals that live in small harems to large herds...

, gazelle
Gazelle
A gazelle is any of many antelope species in the genus Gazella, or formerly considered to belong to it. Six species are included in two genera, Eudorcas and Nanger, which were formerly considered subgenera...

, and wildebeest
Wildebeest
The wildebeest , also called the gnu is an antelope of the genus Connochaetes. It is a hooved mammal...

, the crater is home to the "big five
Big Five game
The phrase Big Five game was coined by white hunters and refers to the five most difficult animals in Africa to hunt on foot. The term is still used in most tourist and wildlife guides that discuss African wildlife safaris. The collection consists of the lion, African elephant, cape buffalo,...

" of rhinoceros
Rhinoceros
Rhinoceros , also known as rhino, is a group of five extant species of odd-toed ungulates in the family Rhinocerotidae. Two of these species are native to Africa and three to southern Asia....

, lion
Lion
The lion is one of the four big cats in the genus Panthera, and a member of the family Felidae. With some males exceeding 250 kg in weight, it is the second-largest living cat after the tiger...

, leopard
Leopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...

, elephant
Elephant
Elephants are large land mammals in two extant genera of the family Elephantidae: Elephas and Loxodonta, with the third genus Mammuthus extinct...

, and buffalo
African Buffalo
The African buffalo, affalo, nyati, Mbogo or Cape buffalo is a large African bovine. It is not closely related to the slightly larger wild Asian water buffalo, but its ancestry remains unclear...

. The crater plays host to almost every individual species of wildlife in East Africa, with an estimated 25 000 animals within the crater.

Following the recommendations of the ad hoc committee of scientists convened after the 2000 drought, an ecological burning program was implemented in the crater, which entails annual or biannual controlled burns of up to 20% of the grasslands. Maasai are now permitted to graze their cattle within the crater, but must enter and exit daily.

Lion death periods and Stomoxys flies

In 1961 there was a drought, and in 1962 rain continued throughout the dry season. This caused a massive build-up of the Stomoxys calcitrans biting fly by May 1962. Their demands for blood meals affected the lions so badly (draining blood, and causing skin sores which became infected) that lion numbers crashed, and took several years to build back up when the weather was back to normal. It was estimated that Ngorongoro's population of at least 70 lions had been reduced to about 10.

Drought in 2000 and continuous dry-season rain in 2001 did the same again: in March 2001 Stomoxys numbers had built up again into a devastating plague..

Olduvai Gorge

The conservation area also protects Olduvai Gorge
Olduvai Gorge
The Olduvai Gorge is a steep-sided ravine in the Great Rift Valley that stretches through eastern Africa. It is in the eastern Serengeti Plains in northern Tanzania and is about long. It is located 45 km from the Laetoli archaeological site...

, situated in the plains area. It is considered to be the seat of humanity after the discovery of the earliest known specimens of the human genus, Homo habilis
Homo habilis
Homo habilis is a species of the genus Homo, which lived from approximately at the beginning of the Pleistocene period. The discovery and description of this species is credited to both Mary and Louis Leakey, who found fossils in Tanzania, East Africa, between 1962 and 1964. Homo habilis Homo...

 
as well as early hominidae
Hominidae
The Hominidae or include them .), as the term is used here, form a taxonomic family, including four extant genera: chimpanzees , gorillas , humans , and orangutans ....

, such as Paranthropus boisei
Paranthropus boisei
Paranthropus boisei was an early hominin and described as the largest of the Paranthropus species...

.

The Olduvai Gorge or Oldupai Gorge is a steep-sided ravine in the Great Rift Valley
Great Rift Valley
The Great Rift Valley is a name given in the late 19th century by British explorer John Walter Gregory to the continuous geographic trench, approximately in length, that runs from northern Syria in Southwest Asia to central Mozambique in South East Africa...

, which stretches along eastern Africa. Olduvai is in the eastern Serengeti
Serengeti
The Serengeti ecosystem is a geographical region in Africa. It is located in north Tanzania and extends to south-western Kenya between latitudes 1 and 3 S and longitudes 34 and 36 E. It spans some ....

 Plains in northern Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

 and is about 30 miles long. It lies in the rain shadow of the Ngorongoro highlands and is the driest part of the region. The gorge is named after 'Oldupaai', the Maasai
Maasai language
The Maasai language is an Eastern Nilotic language spoken in Southern Kenya and Northern Tanzania by the Maasai people, numbering about 800,000...

 word for the wild sisal plant, Sansevieria ehrenbergii
Sansevieria ehrenbergii
Sansevieria ehrenbergii is a flowering plant which grows in northeastern Africa from Libya south to Tanzania,Oman and also in Saudi Arabia. It occurs notably in proliferation along the Olduvai Gorge in northern Tanzania...

.

It is one of the most important prehistoric sites in the world and research there has been instrumental in furthering understanding of early human evolution
Human evolution
Human evolution refers to the evolutionary history of the genus Homo, including the emergence of Homo sapiens as a distinct species and as a unique category of hominids and mammals...

. Excavation work there was pioneered by Mary
Mary Leakey
Mary Leakey was a British archaeologist and anthropologist, who discovered the first skull of a fossil ape on Rusinga Island and also a noted robust Australopithecine called Zinjanthropus at Olduvai. For much of her career she worked together with her husband, Louis Leakey, in Olduvai Gorge,...

 and Louis Leakey
Louis Leakey
Louis Seymour Bazett Leakey was a British archaeologist and naturalist whose work was important in establishing human evolutionary development in Africa. He also played a major role in creating organizations for future research in Africa and for protecting wildlife there...

 in the 1950s and is continued today by their family. Some believe that millions of years ago, the site was that of a large lake, the shores of which were covered with successive deposits of volcanic ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...

. Around 500,000 years ago seismic activity diverted a nearby stream which began to cut down into the sediments, revealing seven main layers in the walls of the gorge.

External links


Further reading

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