The Worldwide Fund for Nature said the decline in the number of hippos has led to a decline of fish stocks and the international conservation group told the BBC there are fewer than 900 hippos left in the park. Thirty years ago there were 29,000 hippopotami living in the eastern Democratic Republic Congo park. Conservationists blame poaching for the decline.
The figures are the result of a survey by the Congolese Institute for the Conservation of Nature, the European Union and the WWF, the BBC said.
The decline of the hippo population has affected thousands of fishermen living around Lake Edward, located inside the national park. Hippopotamus dung provides nutrients for fish, and the reduced number of hippos 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," Marc Languy of the WWF told the BBC.