Resurfaced This fish was thought to be extinct for 20 years

Three years after its first discovery in Cambodia, researchers confirm the existence of the "Mekong ghost", a species of fish long thought to be lost. The discovery gives new hope for the protection of the endangered Mekong River.

In 2020, the discovery of an unknown fish in Cambodia caused a stir in the scientific community. Experts suspected that it could be the "Mekong ghost". This is a fish that is very rarely caught by fishermen and has not been sighted since 2005. It was assumed that the fish was extinct.

In the photos taken after the catch, you can see clear characteristics that are rather unusual. The fish can weigh up to 30 kilograms and has an unusually shaped mouth with a conspicuous button on the jaw.

But before researchers could examine the fish more closely, it had already been sold. "It didn't feel like definitive proof," says Zeb Hogan, a biologist at the University of Nevada in Reno and head of the "Wonders of the Mekong" project, as CNN writes.

Three years later, the proof

The breakthrough came three years later: fishermen from Cambodia discovered two fish that weighed between five and six kilograms and were 60 to 90 centimetres long. This time, the scientists were able to buy and examine the animals.

"Although the fishermen had never seen the fish before, they knew it was something unusual," explained Hogan in a CNN interview. The researchers confirmed their discovery in a study published in the journal "Biological Conservation".

The fish was classified as an official species in 1991

The Mekong, a species-rich river in Southeast Asia, is facing major challenges due to hydropower development, overfishing and habitat destruction. The giant salmon carp, which can grow up to 1.20 meters long, was classified as an official species in 1991, but has only been documented in less than 30 cases since then.

Despite the rare sightings, Hogan is hoping for a turnaround: "It's a sign of hope," he says. Cambodian researcher Bunyeth Chan also sees the rediscovery as an important moment for the protection of the entire Mekong ecosystem.

The Mekong River is under threat

Nevertheless, much remains unknown, such as the exact size of the population or its distribution area. The fish discovered between 2020 and 2023 were outside their usual habitat, which may indicate further undiscovered populations.

However, the researchers emphasize that the Mekong remains threatened by climate change and human interference. Of particular concern is the state of fish species in the river, almost a fifth of which are threatened with extinction, according to a report by the World Wildlife Fund and "Wonders of the Mekong".

The fight against climate change in Cambodia is deadly

In addition to the environmental threats, nature conservation work in Cambodia is also dangerous. Several environmental activists have been imprisoned or killed for denouncing corruption and harmful projects. At the beginning of the year, ten members of the Mother Nature Cambodia group were sentenced to long prison terms, which was sharply criticized internationally, including by Greta Thunberg.

The researchers now hope that the discovery of the giant salmon carp will provide the impetus for further conservation measures, including cooperation between Cambodia, Laos and Thailand. "This fish is an indicator of the health of the river," emphasizes Hogan, "and symbolizes the importance of fish stocks to the local population."