China surveys endangered porpoises amid extinction fears (2)

"Finless porpoises may die out within 10 to 15 years, if strong measures are not taken," Wang warned.

The survey team will trace the porpoises using sonar system along the middle and lower reaches of the river, collecting data on the species' population, which will assist in the making of future protection policies.

The initial results of the survey will be published in December.

"As the flagship species in the Yangtze, finless porpoises are the barometer of the river's ecological conditions," said Wang Kexiong, deputy commander of the survey team.