The feared extinct ‘Mekong Ghost’ resurfaces.

A USAID-funded project has identified an adult giant salmon carp, a fish species that may weigh up to 66 pounds (30 kilograms), in the Mekong River for the first time in 18 years.

One of the world’s most endangered fish species was unexpectedly rediscovered in northern Cambodia.

No adult giant salmon fish (Aaptosyax grypus) have been officially recorded since 2004, however a 13-pound specimen was discovered earlier this year in a local wet market along the Mekong River, the only river where the species lives.

The giant salmon carp is so rare that it has been called a “Mekong Ghost,” and it is highly endangered on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species. Despite the fact that the fish was not discovered alive, and the reason of death is unknown, its discovery has given optimism that the species still exists in the Mekong.

“After more than two decades of work on this topic, I’m so happy to confirm the existence of this unique animal,” said Mr. Chan Sokheng, Deputy Director of the Fisheries Technology Research office with the Cambodian Fisheries Administration’s Inland Fisheries Research and Development Institute (IFReDI).

“This year has been a grand slam for wildlife surprises on the Mekong, but the game is far from over, and victories for biodiversity are still hard to come by,” said Zeb Hogan, a Reno fish biologist at the University of Nevada, who oversees the USAID-funded Wonders of the Mekong research project.

The Mekong River, which flows through six Asian countries, is a worldwide biodiversity hotspot with almost 1,000 different fish species, including some of the world’s largest freshwater fishes. The river provides a living for tens of millions of people, but it has been under growing strain in recent years due to dam construction, overfishing, and climate change, with the largest fish species particularly vulnerable.

“The recent discoveries along the Mekong have resulted through outreach to local people, many of whom have a profound knowledge and dependence on the river and its wild creatures,” stated Ms. Chea Seila, project manager for the Wonders of the Mekong.

The appearance of a three-foot-long specimen in the market indicated the salmon carp’s revival. The merchant immediately contacted Sokheng, and photographs, Sokheng was able to identify it as a huge salmon carp due to its strongly curved jaw, yellow stripe on its head, and fusiform shape like a salmon. 

Scientists will take the DNA from the dead fish to create a variety of instruments for researching the species’ distribution. They hope to find more living specimens that can be tagged and released for further research.

“The discovery of yet another amazing, but critically endangered, animal in an area that supports the livelihoods and food security of millions of people underlines the urgent need for conservation programmes and the potential benefits of government, scientists, and local communities working together to protect the Mekong’s wonders,” said Hogan.

Sourec: Wonders of the Mekong