of the lion population died between January and April from a combination of tick-borne disease and canine distemper. The lion population is also influenced to some extent by the takeover of prides by incoming males, which typically kill small cubs. The biggest influence, however, appears to be disease, particularly canine distemper. Outside Ngorongoro Crater The Ngorongoro Conservation Area has a healthy resident population of most species of wildlife. The Ndutu Lake area to the west of the conservation area has particularly strong cheetah and lion populations. Common in the area are hartebeest (Alcelaphus buselaphus), spotted hyena (Crocuta crocuta), and jackals. The population of African wild dog may have declined recently. Servals occur widely on the plains to the west of the Ngorongoro Crater. The annual ungulate migration passes through the Ngorongoro Conservation Area, with 1.7 million wildebeest, 260,000 zebra, and 470,000 gazelles moving into the area in December and moving out in June. This movement changes seasonally with the rains, but the migration traverses almost the entire plains in search of food. See also List of reduplicated place names List of Ngorongoro Crater plants References Further reading Ngorongoro Conservation Area at the UNEP World Conservation Monitoring Centre External links Ngorongoro Conservation Area Authority Ngorongoro crater facts Explore Ngorongoro Conservation Area in the UNESCO collection on Google Arts and Culture Tanzania Tourist Bureau UNESCO World Heritage Site Datasheet Biosphere reserves of Tanzania Geography of Arusha Region Volcanoes of Tanzania Calderas of Africa Tourist attractions in the Arusha Region World Heritage Sites in Danger World Heritage Sites in Tanzania Protected areas established in 1959 1959 establishments in Tanganyika East African montane forests Serengeti volcanic grasslands Southern Acacia-Commiphora bushlands and thickets Important Bird Areas of Tanzania