NANCHANG, April 13 (Xinhua) -- It had been almost 10 years since Wang Shengbian, an aquatic animal specialist, last saw an ochetobius elongatus in Poyang Lake, China's largest freshwater lake.

The fish, about 23 cm long and weighing 47.4 grams, was discovered during routine monitoring of the lake.

Ochetobius elongatus used to be a common fish species in the Yangtze River basin. However, due to environmental destruction, overfishing and human disturbance, the fish stock has reduced rapidly. It has become a critically endangered species.

"I was pleasantly surprised and contacted other experts to double-check the species," said Wang. "The small fish is about one year old, which indicates that its population is recovering."

According to Wang, the last time the species was spotted was in 2012. "It was like they had disappeared for a decade," he said. "Poyang Lake has been 'sick.'"

On Jan. 1, 2021, a 10-year fishing ban took effect in pivotal waters of the Yangtze, after 332 conservation areas along the river enforced the fishing ban a year ago, to help the river recover from dwindling aquatic resources and degrading biodiversity.

A 10-year fishing ban was also implemented at Poyang Lake from the very beginning of 2020. Some 100,000 fishermen near the lake have bid farewell to their centuries-old way of life and moved ashore.

"Ochetobius elongatus is back just one year after the fishing ban was implemented, which means the ban really works," said Zhan Shupin with the department of agriculture and rural affairs in east China's Jiangxi Province.

"Now, scientists use fishing nets in the lake only for scientific monitoring, and they can catch 200 or 300 fish in one net, compared to 40 or 50 before," Zhan said.

A video filmed by Zhan in mid-March showed that the waters near Mount Kangshan were full of long-lost scenes of fish leaping out of the water and spawning.

In June last year, scientists also saw a school of over 100 ribbonfish, the first time in nearly a decade that such a large population of the species has been identified.

The population of finless porpoise, which is believed to be the last surviving mammal in the Yangtze, China's longest river, is expected to increase from about 450 now to 700 in the next decade, according to Zhan.

"The magnificent scenes of cranes dancing and fish leaping over the flowing streams will soon reappear in Poyang Lake," said Zhan expectantly.