River dolphin specie endangered by death of 10 members

The death of 10 river dolphins in Cambodia, probably because of environmental pollution, threatens the survival of the species in the Mekong, the World Wildlife Fund (WWF) said on Friday.
WWF estimates that there are only 80 to 100 of the Irrawaddy dolphins left in the river. Of the 10 that died, eight were calves, and the loss of the young will threaten future reproduction, the Gland, Switzerland-based organisation said.

"This is terrible news, making a serious situation even more critical," said WWF's Robert Mather. "This time of year commonly sees a peak in dolphin deaths; however, 10 in the last two months is particularly high and disappointing since none have been reported since May 2005."

The loss of the calves continues a "worrying trend" of high death rates in baby dolphins in the Mekong river, WWF said.

Cause to be revealed

"This trend has been seen for a number of years and is suspected to be due to some form of environmental pollution. However, ongoing tissue samples and chemical analysis have yet to reveal the cause," the organisation said in a statement.

The remaining 80 to 100 dolphins are now restricted to a 190km stretch of the river between the Cambodia-Laos border and the Cambodian town of Kratie, upstream from the capital Phnom Penh.

"River dolphins like the Irrawaddy are the waters' watchdogs," said Jamie Pittock, a freshwater expert at WWF. "When high levels of toxic pollutants accumulate in their bodies this is a stark warning of poor water quality for dolphins and the people who live from the river."

At least one of the dead dolphins was killed by entanglement in fishing nets, probably the single greatest threat freshwater dolphin species, WWF said.