The Ngorongoro Conservation Area is a protected region and a UNESCO World Heritage Site in Tanzania. It is located in the Ngorongoro District, 180 kilometers west of Arusha City in the Arusha Region. The area is named after the Ngorongoro Crater, a large volcanic caldera. The Ngorongoro Conservation Area Authority (NCAA) manages the region. This authority is part of the Tanzanian government, and its boundaries match the Ngorongoro District. The western part of the area is next to the Serengeti National Park. Together, the Ngorongoro Conservation Area, Serengeti National Park, and Kenya’s Maasai Mara game reserve are home to the Great Migration, an annual movement of millions of wildebeest, zebras, gazelles, and other animals. The area also includes Olduvai Gorge, a site of great importance for studying ancient human history.

In 2023, 752,232 visitors traveled to the Ngorongoro Conservation Area. The 2009 Ngorongoro Wildlife Conservation Act limited human settlement and farming in the Crater, moving Maasai pastoralists away from their homes. Most of these people had been relocated to Ngorongoro from their original lands in the north when the British government created Serengeti National Park in 1959.

History

The name of the crater comes from a sound, as it was named by the Maasai pastoralists after the noise made by a cowbell (ngoro ngoro). Fossil evidence from OH 7 found at the Olduvai Gorge shows that different early human relatives lived in the area for at least 1.75 million years.

Hunter-gatherers were replaced by pastoralists several thousand years ago. The Iraqw people arrived about 2,000 years ago, and the Datooga joined them around the year 1700. Both groups were later driven out of the area by the Maasai in the 1800s.

No Europeans were known to have visited the Ngorongoro Crater until 1892, when a man named Oscar Baumann explored it. Two German brothers, Adolph and Friedrich Siedentopf, farmed in the crater until World War I began, after renting the land from the German East Africa administration. They held hunting events for their German friends and tried to move wildebeest herds out of the crater.

The first game reserves were created by Germans, allowing hunting. After World War I, when Britain took control, rules to protect wildlife were introduced in Tanzania (then called Tanganyika) starting in 1921. By 1930, the Ngorongoro Crater was included in these protections. A law passed in 1923 gave the governor the power to decide land rights for indigenous people, though these rights remained with them until the 1950s. Tensions grew between efforts to protect wildlife and the rights of local people during this time.

In 1948, a law (implemented in 1951) created the Serengeti National Park. To ensure the Maasai people, who lived in the area, could keep their land, the Ngorongoro Conservation Area was separated from the Serengeti in 1959. Maasai people living in Serengeti National Park were moved to the Ngorongoro Conservation Area, increasing the number of Maasai there. This also caused more conflicts between the Tanzanian government and the Maasai.

The Ngorongoro Conservation Area Authority (NCAA) was created at the same time. It manages the NCA and works to protect it as a place where nature and human traditions can coexist. The NCAA’s goal is to support the Maasai’s way of life, preserve the natural and cultural values of the area, and manage tourism.

The Ngorongoro Conservation Area became a UNESCO World Heritage Site in 1979 because of its natural beauty and the Ngorongoro Crater. In 2010, it received recognition for its cultural value, including the Olduvai Gorge’s importance for studying human history. However, the Maasai community was not included in this recognition, leading to ongoing conflicts over how the area is used and managed.

The Wildlife Conservation Act of 2009 limited human activities in the Ngorongoro Crater and created rules that made it harder for traditional Maasai pastoralists to live there. The International Union for Conservation of Nature (IUCN) is working to find solutions to reduce conflicts and improve cooperation with local people for conservation.

In 2021, the Tanzanian government began a plan to move all Maasai people living in the Ngorongoro Conservation Area to a village called Msomera, 600 kilometers away. The government calls this a voluntary relocation, but Human Rights Watch reports that the process has been forced, without following the principle of free, prior, and informed consent (FPIC).

Geography

The Serengeti ecosystem includes several protected areas in Tanzania. The Ngorongoro Conservation Area (NCA) is located in the southeast (shown in dark grey). The NCA is next to the Serengeti National Park (SNP) to the northwest and connects to the SNP's southern Serengeti plains. These plains also extend north of the NCA into the unprotected Loliondo division. The Maasai people keep these areas open for wildlife by practicing a type of farming called transhumance pastoralism. The south and east of the NCA are volcanic highlands, including the well-known Ngorongoro Crater and the less-known Empakaai Crater.

The southern and eastern edges of the Serengeti ecosystem are roughly marked by the edge of the East African Rift wall, which stops animals from migrating in those directions. On a topographical map, Lake Nyanza is the same as Lake Victoria in the Serengeti Ecosystem map.

The Pliocene Ngorongoro volcanic group includes eight extinct shield volcanoes in the Eyasi half-graben, with the eastern boundary marked by the Gregory Rift Western Escarpment. The Lake Eyasi escarpment forms the southwest edge of the half-graben. Five of the volcanoes in this group have dome-shaped cones, while three have calderas. Ngorongoro Volcano (2.5–1.9 million years old) is mainly made of basaltic trachyandesite. The caldera is fed by the Munge and Oljoro Nyuki Rivers, while the Ngoitokitok hot springs flow into the Goringop swamp. Lake Magadi is a shallow (1.7 meters) alkaline lake. Other volcanoes in the group include Olmoti (2.01–1.79 million years old), Empakaai, Loolmalasin, Sadiman (3.7 million years old), Lemagrut, and Oldeani. The northwest part of the NCA includes the Serengeti Plains, the Salei Plains, the Oldupai Gorge, and the Gol Mountains inselbergs. These inselbergs are part of the Mozambique Belt quartzite and mica schist, which are about 800–500 million years old.

Ngorongoro Crater

The main feature of the Ngorongoro Conservation Area is the Ngorongoro Crater, which is the world's largest inactive, intact, and unfilled volcanic caldera. This crater formed when a large volcano erupted and then collapsed in on itself about two to three million years ago. It is 610 meters (2,000 feet) deep, and its floor covers an area of 260 square kilometers (100 square miles). Scientists estimate that the original volcano was between 4,500 and 5,800 meters (2.8 to 3.6 miles) tall. The crater floor is located 1,800 meters (5,900 feet) above sea level. In February 2013, the crater was named one of the Seven Natural Wonders of Africa by the Seven Natural Wonders organization in Arusha, Tanzania. The Ngorongoro volcano was active from about 2.45 to 2 million years ago. Volcanic eruptions similar to the one that formed the Ngorongoro Crater were common in the region. Similar collapses happened at Olmoti and Empakaai, but these were smaller in size and effect. Two recent volcanoes near the Empakaai caldera are Kerimasi and Ol Doinyo Lengai. Ol Doinyo Lengai is still active and had major eruptions in 2007 and 2008. Smaller eruptions and lava flows continue to slowly fill the crater. The crater's name in the Maasai language means "Mountain of God." The Munge Stream flows from the Olmoti Crater to the north and is the main source of water that drains into the seasonal salt lake in the center of the crater. This lake is called "Makat" by the Maasai, meaning "salt," and "Magadi" in another language. The Lerai Stream flows from the humid forests to the south of the crater and provides water to the Lerai Forest on the crater floor. During rainy seasons, the Lerai Stream also flows into Lake Magadi. Water use by lodges and the Ngorongoro Conservation Area headquarters reduces the amount of water flowing into the Lerai Stream by about 25%.

Another major water source in the crater is the Ngoitokitok Spring, located near the eastern side of the crater. This area has a picnic site for visitors, a large swamp fed by the spring, and is home to animals such as hippos, elephants, lions, and others. Many smaller springs are found across the crater floor and provide important water sources for animals and the local Maasai people, especially during droughts. Previously, the Maasai were allowed to graze their cattle inside the crater, but this practice was stopped in 2015.

Olduvai Gorge

The Ngorongoro Conservation Area also protects Olduvai Gorge, located in the plains area. It is considered an important place in human history because scientists discovered the earliest known remains of the human genus, Homo habilis, and early hominidae, such as Paranthropus boisei.

Olduvai Gorge is a deep valley in the Great Rift Valley, which runs along eastern Africa. It is found in the eastern Serengeti Plains in northeastern Tanzania and is about 50 kilometers (31 miles) long. The gorge is in the rain shadow of the Ngorongoro highlands, making it the driest part of the region. Its name comes from "Oldupaai," a Maasai word for the wild sisal plant, Sansevieria ehrenbergii.

Olduvai Gorge is one of the most important prehistoric sites in the world. Research there has helped scientists learn more about early human evolution. Excavation work began in the 1950s by Mary and Louis Leakey and continues today by their family. Some scientists think the area was once a large lake, with volcanic ash layers covering its shores. About 500,000 years ago, ground shaking redirected a nearby stream, which carved into the sediments and exposed seven main layers in the gorge’s walls.

Wildlife

Approximately 25,000 large animals, mostly hoofed animals, live in the crater. Large mammals in the crater include the black rhinoceros (Diceros bicornis michaeli). The local population of this animal decreased from about 108 in 1964–66 to 13 in 1993. Because of efforts by the Frankfurt Zoological Society, International Rhino Foundation, and World Wildlife Fund to monitor and protect the rhinos, the current total is 55 animals as of 2018.

Other large mammals in the crater include the African buffalo or Cape buffalo (Syncerus caffer) and the hippopotamus (Hippopotamus amphibius). Many other hoofed animals also live in the crater, such as the blue wildebeest (Connochaetes taurinus) (about 7,000 in 1994), Grant’s zebra (Equus quagga boehmi) (about 4,000), the eland (Taurotragus oryx), and Grant’s (Nanger granti) and Thomson’s gazelles (Eudorcas thomsonii) (about 3,000). Waterbucks (Kobus ellipsiprymnus) are mostly found near Lerai Forest.

Giraffes, impalas (Aepyceros melampus), topis (Damaliscus lunatus), oribis (Ourebia oribi), and crocodiles (Crocodylus niloticus) are not found in the crater.

Cheetahs (Acinonyx jubatus raineyi), East African wild dogs (Lycaon pictus lupinus), and African leopards (Panthera pardus pardus) are rarely seen in the crater. Spotted hyenas (Crocuta crocuta) have been studied in the crater since 1996.

Although the crater is considered a natural enclosure for many types of wildlife, 20 percent or more of the wildebeest and half the zebra populations leave the crater during the wet season. Cape buffalo (Syncerus caffer) remain in the crater, and their numbers are highest during the rainy season.

Since 1986, the wildebeest population in the crater has dropped from 14,677 to 7,250 (2003–2005). The numbers of eland and Thomson’s gazelle have also decreased, while the buffalo population has grown significantly. This may be due to the long prevention of fires, which helps high-fibrous grasses grow better than shorter, less fibrous types.

Servals (Leptailurus serval) are found throughout the crater.

Lake Magadi, a large lake in the southwest of the crater, is often home to thousands of mainly lesser flamingos.

The crater has one mammal species that is found only there: Mduma’s shrew (Crocidura mdumai). This shrew lives only in montane forests near the edge of the crater and is considered endangered because of deforestation caused by smallholder farming.

The crater has one of the densest known populations of lions, with 62 lions in 2001.

A side effect of the crater being a natural enclosure is that the lion population is significantly inbred. This happens because very few new lions enter the crater from outside. Those that do often cannot contribute to the gene pool because the male lions already living in the crater drive away outside competitors.

Long-term data show that lions in the crater experienced four deadly disease outbreaks between 1962 and 2002. Drought in 1961 and heavy rains in 1962 caused a large increase in blood-sucking stable flies (Stomoxys calcitrans) by May 1962. These flies caused painful skin sores that became infected, reducing the lion population from 75–100 to 12. The population recovered to about 100 by 1975 and remained stable until 1983, when a decline began. Lion numbers have generally been below 60 since 1993, reaching a low of 29 in 1998. In 2001, 34 percent of the lion population died between January and April due to a combination of tick-borne disease and canine distemper.

The lion population is also affected by male lions taking over prides, which often results in the death of small cubs. However, the biggest influence on the lion population appears to be disease, especially canine distemper.

Outside Ngorongoro Crater

The Ngorongoro Conservation Area is home to many animals and the Masai people. Near the Ndutu Lake in the west, there are large groups of cheetahs and lions. Hartebeest, spotted hyenas, and jackals are often seen in the area. The number of African wild dogs might be getting smaller now. Servals are found in many places on the plains west of the Ngorongoro Crater.

Every year, many hoofed animals migrate through the conservation area. Over 1.7 million wildebeest, 260,000 zebras, and 470,000 gazelles enter the area in December and leave in June. This movement depends on the rainy seasons, and the animals travel across most of the plains to find food.

Threats to the conservation area

The 2020 Conservation Outlook Assessment by the International Union for Conservation of Nature (IUCN) World Heritage Outlook highlights challenges for protecting the Ngorongoro Conservation Area (NCA) successfully. These challenges include:

• The growing population of the Maasai people, who are pastoralists (livestock herders).
• The need to manage tourism and visitor activities in a way that supports the environment and local communities.

The NCA is unique because it is the only conservation area in Tanzania that protects wildlife while allowing people to live there. The Maasai people who live in the NCA are allowed to use the land, but their activities are limited to avoid harming wildlife. For example, farming is only allowed at a level that meets basic needs.

In 1966, about 8,700 Maasai lived in the NCA. By 2017, this number had grown to 93,136. It is expected to reach 161,000 by 2027. This population growth has caused other problems, such as:
– More livestock, which may lead to overgrazing (using land more than it can support).
– Cutting too much wood from the land for homes and buildings.
– Construction that could harm the natural beauty of the area.

One proposed solution is to move some Maasai to the village of Msomera, which is 600 kilometers (370 miles) away. This effort began in 2021. The Ngorongoro Conservation Area Authority provides money and land to those who choose to move. However, this plan has caused conflicts between existing residents of Msomera and new arrivals. Some people are also worried that the rights of all involved have not been fully protected.

The Ngorongoro Conservation Area Authority manages and protects the NCA. It depends heavily on income from tourism to fund conservation efforts and share money with local communities. If tourism declines, this income could be lost. In 2022/23, the NCA had 752,232 visitors, which was a new record.

Most tourists visit the Ngorongoro Crater, which is a small part of the NCA. To reduce traffic there, rules have been added:
– Higher fees are charged for each vehicle entering the crater.
– Only 50 vehicles can enter the crater at the same time.
– Vehicles are encouraged to carry more passengers.
– Tourist businesses must follow rules to reduce their impact on the environment.