Staff members release the Chinese sturgeon in Yichang, central China's Hubei Province, April 8, 2017. (Xinhua/Xiong Qi)
About 500 captive-bred Chinese sturgeon were released Saturday into a section of the Yangtze River in central China's Hubei Province to increase the wild population of the rare species.
The released sturgeon, aged between three and six years old, are around 110 centimeters long and weigh about 5.5 kilograms on average.
This is the 59th release by the Chinese Sturgeon Research Institute of China Three Gorges Corp., which has introduced more than five million sturgeon to the wild since the 1980s.
Believed to have lived at the same time as dinosaurs, the Chinese sturgeon has existed for more than 140 million years. The fish is under top national protection.
Due to water projects, river traffic and pollution, the number of wild Chinese sturgeon, which migrate to Hubei's Gezhou Dam to reproduce, has fallen from about 1,000 in 1982 to about 50, according to researchers' estimates.
Wild sturgeon, once mature, usually swim from the sea to suitable river areas to lay eggs around mid and later November.
