Irrawaddy dolphins near extinction as Mekong region develops

Hydropower dams are shrinking freshwater pools in their main habitat, leading to more contact with fishermen who threaten their survival. PHOTO: ST FILE

PHNOM PENH - There are only 80 Irrawaddy dolphins left in a loosely-patrolled stretch of the Mekong River in central Cambodia.

Hydropower dams are shrinking freshwater pools in their main habitat, leading to more contact with fishermen who threaten their survival.

Three dolphins died in December, accounting for about 5 per cent of their population in the Mekong.

Cambodia’s Premier Hun Sen recently called for the creation of conservation zones to protect the mammal, which numbers about 250 globally.

Environmentalists doubt this will be enough in the region, where fishing is technically forbidden, but law enforcement is weak.

“While the direct deaths are caused by fishing gear – entanglement in gillnets and longline hooks – this is a problem of Cambodia itself,” said Ms Daphne Willems, a coordinator of river dolphin conservation at the World Wide Fund for Nature (WWF).

China’s recent construction of 11 hydropower dams upstream has exacerbated the problem, according to a United States House Subcommittee testimony in December from Mr Brian Eyler, who studies the Mekong region at the Stimson Centre.

The Mekong, the world’s 12th largest river, stretches more than 4,345km from Tibet through China and South-east Asia. It is a key economic cog for one of the world’s fastest-developing areas.

“Laos and Cambodia are the most vulnerable to what their neighbours do to the river system, whether that is building dams which alter the Mekong’s natural flow, removing sand and sediment from the river for industrial and urban development, or polluting the river with plastics and industrial waste,” Mr Eyler told the committee.

Conservationists have some reason for optimism should actions be enforced on the waterway.

The Endangered Species Act, which was signed into law by former US president Richard Nixon in 1973, was widely credited for saving the American bald eagle. Australia’s successful legislation to support the humpback whale has also yielded results.

Using the Mekong River for profit threatens not just Irrawaddy dolphins but also an entire ecosystem. 

Laos alone has 100 Mekong dams lined up for the future. Countries are racing to export hydropower and become the “Battery of South-east Asia”, according to Mr Eyler.

The Stimson Centre is pushing for a smarter engagement strategy from the US to keep the Mekong region thriving.

In December, the WWF and Cambodian authorities learnt of a dead female dolphin of breeding age. Her death was a blow to the breeding potential of Mekong’s dolphins, about 70 per cent of which are over 20 years old. 

“This death rate has not been seen in the last 10 years,” said Mr Seng Teak, country director for WWF Cambodia. “If this situation is not immediately addressed, this species will go extinct on our watch.” BLOOMBERG

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