Phnom Penh: The World Wildlife Fund (WWF) calls for an urgent action to protect the critically endangered Irrawaddy dolphin population in the Mekong River, WWF`s new research said.
In a statement sent to China`s Xinhua news agency on Wednesday, WWF said that the calf survival was found to be very low and it is concluded that the small population is declining and is at high risk of extinction.
Irrawaddy dolphins (Orcaella brevirostris) inhabit a 190km stretch of the mainstream Mekong River between Kratie, Cambodia and Khone Falls on the border with Lao.
Currently, there are 85 Irrawaddy dolphins left in Southeast Asia`s Mekong River.
Director of WWF`s Freshwater Programme Dr Li Lifeng said surveys conducted from 2007 to 2010 show the population is slowly declining.
"Evidence is strong that very few young animals survive to adulthood, as older dolphins die off and are not replaced," Dr Li explained, as many die due to pressures of gill net entanglement.
The research, said Li, is based on photographic identification of dolphins through individually unique features of their dorsal fins.
"Most of the dolphins can be identified, and we use that information to estimate the population size," he said.
Although this population estimate is slightly higher than the previous estimate, the researchers were quick to note that the population had not increased over the last few years.
"With a larger dataset and recent analytical advances, previously unidentifiable dolphins which had few marks on their dorsal fins have been included," he added.