A scientific survey on the Yangtze River to review the status of the endangered finless porpoise was launched in Wuhan, Hubei province, on Friday. Its findings are expected to be released in March.

Financed by World Wildlife Fund and local foundations in the province, the survey is the third to be undertaken by the Ministry of Agriculture since 2006. It is being led by the Chinese Academy of Sciences' Institute of Hydrobiology.

"Allowing for the decline in porpoise's population and distribution, the survey can show variations more accurately if carried out every five to six years," said Hao Yujiang, a researcher at the institute who is in charge of the work.