The Yangtze river dolphin, or baiji swims in China's largest Yangtze River. [File photo]

Professor Yu Daoping knows the ins and outs of the Yangtze river dolphin, having dissected more than 200 corpses of the finless porpoise over the last 20 years.

When not teaching university, he spends his time as the chief consultant for the newly set-up Xijiang River Finless Porpoise Rescue Center in Anqing city, Anhui Province, tracking the cause of death among the 25-million-year old species.

"Dead dolphins salvaged along the Yangtze River had no food in their stomach, and scars from wounds covered their bodies," he said of one of the most recent incidents.

He said starvation and injuries by motor rotor blades on vessels are the main lethal factors threatening the endangered dolphin's survival.

The Anqing Fishery Bureau recently transported five wounded Yangtze River finless porpoise found this year to Xijiang River, a 10-km long old waterway section of Yangtze, and helped establish the rescue center.

Friday will coincide with the International Freshwater Dolphin Day. The day set in 2010 for the preservation of the freshwater mammal was also claimed by the World Wide Fund for Nature (WWF) as a sad reminder of the recently lost Yangtze white-finned dolphin, known in Chinese as Baiji Dolphin, which is bigger than the finless porpoise.