Hippopotamus amphibius

Distribution and status
Hippopotamus amphibius was widespread in North Africa and Europe during the Eemian[48] and late Pleistocene until about 30,000 years ago. Archaeological evidence exists of its presence in the Levant, dating to less than 3,000 years ago.[49][50] The species was common in Egypt’s Nile region during antiquity, but has since been extirpated. Pliny the Elder writes that, in his time, the best location in Egypt for capturing this animal was in the Saite nome;[51] the animal could still be found along the Damietta branch after the Arab Conquest in 639. Reports of the slaughter of the last hippo in Natal Province were made at the end of the 19th century.[52] Hippos are still found in the rivers and lakes of the northern Democratic Republic of the Congo, Uganda, Tanzania and Kenya, north through to Ethiopia, Somalia and Sudan, west to The Gambia, and south to South Africa.[1]

Ugandan tribespeople with hippo slain for food (early 20th century)

Incised hippopotamus ivory tusk, upper canine. Four holes around top (Naqada Tomb 1419, Egypt; Naqada period)
Genetic evidence suggests that common hippos in Africa experienced a marked population expansion during or after the Pleistocene, attributed to an increase in water bodies at the end of the era. These findings have important conservation implications as hippo populations across the continent are currently threatened by loss of access to fresh water.[9] Hippos are also subject to unregulated hunting and poaching. In May 2006, the hippo was identified as a vulnerable species on the IUCN Red List drawn up by the International Union for Conservation of Nature (IUCN), with an estimated population of between 125,000 and 150,000 hippos, a decline of between 7% and 20% since the IUCN’s 1996 study. Zambia (40,000) and Tanzania (20,000–30,000) possess the largest populations.[1]

The hippo population declined most dramatically in the Democratic Republic of the Congo.[53] By 2005, the population in Virunga National Park had dropped to 800 or 900 from around 29,000 in the mid-1970s.[54] The decline is attributed to the disruptions caused by the Second Congo War.[54] The poachers are believed to be Mai-Mai rebels, poorly paid Congolese soldiers, and local militia groups.[54][55] Reasons for poaching include the belief that hippos are harmful to society, as well as financial gain.[56] However, as of 2016, the Virunga hippo population appears to have increased, possibly due to greater enforcement and cooperation between fishermen and park authorities.[57] The sale of hippo meat is illegal, but black-market sales are difficult for Virunga National Park officers to track.[55][56] Hippo meat is considered a delicacy in some areas of central Africa and the teeth have become a valued substitute for elephant ivory.[58]