GUIYANG, July 10 (Xinhua) -- Yangtze sturgeon have managed successful natural spawning in China's Chishui River, a tributary of the country's longest waterway -- the Yangtze River, after the removal of over 300 small hydropower stations in the river basin, marking a breakthrough for the conservation of this critically endangered species.

The Yangtze sturgeon, declared extinct in the wild in 2022 by the International Union for Conservation of Nature, had not been seen reproducing naturally since 2000, due to habitat fragmentation caused by hydropower dams and shipping development.

In April 2025, 20 adult Yangtze sturgeons were released into the Chishui River in southwest China's Guizhou Province and later found to spawn naturally, with researchers observing successful hatching in the river's Dayuba section in the city of Chishui.

From 2020 to 2024, three Chinese provinces -- Yunnan, Sichuan and Guizhou -- decommissioned 342 small hydropower stations in the Chishui River basin, accounting for 91.7 percent of the total; 300 dams were dismantled, representing 84 percent. These removal efforts reconnected tributaries, ensuring water flow and spawning grounds for migratory fish.

"The Chishui River's ecology now meets the Yangtze sturgeon's habitation and breeding needs," said Liu Fei, an associate researcher at the Institute of Hydrobiology of the Chinese Academy of Sciences.

The hatching success stands in contrast to previous conservation attempts in the Yangtze's main stream, where researchers observed natural sturgeon spawning, only for the eggs to fail to hatch in the river environment.

Notably, the Chishui River, with its long course and abundant water volume, is suitable for carrying out in situ research and protection of rare and endemic fish species.

In 2023 and 2024, the agricultural and rural affairs authorities in Guizhou released nearly 2,000 young Yangtze sturgeons into the Chishui River in two batches. Tracking through markers showed that these sturgeons successfully adapted to the wild environment and are growing well.

Liu explained that for migratory fish that seasonally move between breeding and non-breeding habitats, unobstructed river channels are crucial as they need to travel to find suitable spawning or wintering grounds.

The small hydropower stations, which were built in the 1950s and 1960s to mitigate local power shortages, have now been removed as part of China's broader Yangtze River protection strategy, which includes a 10-year comprehensive fishing ban.

Authorities assessed each dam, retaining only those with essential flood-control functions while removing others only after ensuring local water needs would still be met, said Yi Yun, head of the water resources department of Guizhou.

"These measures have significantly reduced hydropower density along the Guizhou section of the river, reconnected over 20 tributaries to the main stream and boosted fish populations," Yi said.

These extensive dam removals from the Chishui River stem from its vital role in protecting rare fish species and China's growing ecological awareness, with the coordination efforts of the three provinces producing regulations on river conservation, said Xing Yuanyue, an official with the Ministry of Water Resources.

On June 17, China's central authorities issued a policy elevating river protection to unprecedented importance, mandating comprehensive ecosystem restoration, ensuring river connectivity and introducing a new basin-wide coordination mechanism, under which provinces, cities and counties in the same river basin should be coordinated for river conservation.

"The three-province collaboration on Chishui River conservation has perfectly exemplified the basin-wide coordination mechanism," Xing said.