In 1988, Liu graduated from the Aquaculture Department at Guangdong Ocean University. Located in Zhanjiang, Guangdong province, the university is one of the country's top institutes for aquaculture. Soon, Liu found a job at the institute, which is located in the upper reaches of the Yangtze.

Since Liu was appointed as director of the institute in 2002, he started to improve the feed formula, breeding devices and techniques, and has achieved major technological breakthroughs in the breeding of the species－the institute became the country's earliest national original breeding base for Chinese suckers in 2005.

In April, the institute announced that it has incubated nearly 10 million baby Chinese suckers this year－nearly 4 million more than last year.

"The accumulated experience of breeding Chinese suckers can be applied in breeding other rare fish," said Wang.

After years of scientific research and practice carried out by Liu and the "fish dads", the institute has become one of the best breeding bases for rare fish in southwestern China－with an annual breeding capacity of around 50 million fish fry.

For now, the institute has reserved more than 3,000 parent fish including Yangtze sturgeon, which is under first-class State protection in China, and the Yanyuan carp, Onychostoma angustistomata and Percocypris pingi.

Stretching over 6,300 km, the Yangtze has rich biodiversity, but overfishing and pollution have threatened aquatic life and depleted fish stocks. Last year, China imposed a 10-year fishing ban to help reverse the trend.

To strengthen the ecological balance of the river in the past decade, Wanzhou has released more than 70 million rare fish into the reservoir area.

"Now home to 128 species, fishery resources in the Wanzhou section have been significantly restored. You can see the Yangtze taking on a beautiful and harmonious look, with real big fish in it," said Liu. "The water quality will be significantly improved within three to five years."

"It is hard to let ancient species adapt to the modern environment," Wang said regretfully after hearing that the International Union for Conservation of Nature and Natural Resources had announced the extinction of the Chinese paddlefish and the wild Yangtze sturgeon in its updated Red List of threatened species on July 21.

"But we will strive harder in protecting those that remain."