Updated

Only 887 hippos are left in Congo, once home to the world's largest population of the water-loving mammal, and they will be extinct in the African country, an international environmental group warned Monday.

Hippos are being killed by government soldiers, local militia and poachers, the World Wildlife Fund said. The meat is sold as food while teeth end up as part of the illegal ivory trade. Hippos fetch around $50 per animal.

The latest aerial survey puts the hippopotamus population in northeastern Congo's Virunga National Park down to under 1,000 animals, compared to some 29,000 in 1974. The last survey in 2003 counted 1,307.

The continued presence of soldiers and armed groups in the park — a UNESCO World Heritage Site with a 400-mile-long boundary — has made it difficult to protect the animals, the WWF said.

"Soldiers are left in the park without being fed nor paid and that's a recipe for disaster," said Marc Languy (search), who heads WWF's regional program.

Following a five-year war in this central African country, the postwar transitional government has had little success in calming the east, where killings, looting and rapes continue almost unabated.

Conducted last month, the hippopotamus survey was carried out by the Congolese Institute for Conservation of Nature, the European Union and WWF.

The disappearance of hippos also triggers serious secondary effects for the population, the WWF said. Because hippo dung provides vital nutrients for the fish in Lake Edward, its absence has led to a rapid decline of the lake's fish stocks.

"If the government does not take the hippo situation in Virunga seriously, this will not only lead to an environmental disaster, but also to an economic crisis for local communities," Languy said.