there were an estimated 1,900,000 non-breeding Lesser Flamingo (Phoeniconaias minor) individuals and 40,000 Greater Flamingo (Phoenicopterus roseus). Great white pelican (Pelecanus onocrotalus) can also be present in large numbers (an estimated 200,000 individuals in 1991) and in all there has been an estimated 1,000,000-2,499,999 individual water birds, however, only 78,320 birds were counted in 1994. The groundwater forest to the north of the lake, and largely within the National Park, is a well-known breeding site for thousands of pink-backed pelican (Pelecanus rufescens) and yellow-billed stork (Mycteria ibis) along with smaller numbers of Marabou stork (Leptoptilos crumeniferus) and grey heron (Ardea cinerea). Over 40 species of birds of prey are documented, including palm-nut vulture (Gypohierax angolensis) and Ayre's hawk eagle (Hieraaetus ayresii). In all, more than 390 species of birds have been documented in the national park, although in the dry season, flamingos and other water birds are usually found only in small numbers. Mammals Populations of large migratory mammals that are concentrated primarily in Tarangire National Park, but also move through Lake Manyara National Park include wildebeest, zebra, Thomson's gazelle and Grant's gazelle. Large herds of wildebeest and other plains game from the Mto wa Mbu Game Controlled Area enter the park from the north for short periods. Wildebeest exclusively graze the alkaline grasslands around the lake, and numbers are highest during the dry season, dropping to small resident populations in the wet season. Herbivores of Lake Manyara National Park include zebra, bushbuck, waterbuck, Grant's gazelle, impala, Thomson's gazelle, Cape buffalo, giraffe, hippopotamus, baboon, warthog, and elephant. Studies in the 1980s found this to be one of the areas with the highest wildlife biomass in Africa, but elephant numbers had fallen by 75% between 1985 and 1991 as a result of illegal hunting, with numbers rebounding to around 200 in 1996. Lake Manyara was also once known for its high population of black rhinoceros, but none were present by 1996. Similarly, reedbuck were present in 1984, but no individuals were found in a 1996 census. Predators of Lake Manyara National Park include lion, leopard, African wild cat, spotted hyena, black-backed jackal, bat-eared fox, serval, honey badger, African civet, genet (Genetta) species and several mongoose species. Cheetah and African golden cat are sighted occasionally. Fish Lake Manyara is the type locality for the endangered fish Oreochromis amphimelas, a species of in the cichlid family. It is endemic to Tanzania, and also