BEIJING -- Approximately 550,000 artificially-bred Chinese sturgeon were released into rivers in various parts of the country on Saturday, according to China's agriculture ministry.

The releases, organized by the Ministry of Agriculture and Rural Affairs, were simultaneously held in Jingzhou and Yichang in Central China's Hubei province, as well as Chongming district in Shanghai.

During the event, experts and units related to Chinese sturgeon breeding and conservation held in-depth discussions on protection and artificial breeding technologies related to the species, according to the ministry.

The Chinese sturgeon is a national first-class protected aquatic wild animal and a flagship species of the Yangtze River. Expanding restocking efforts is a key measure to restore natural reproduction and rebuild wild populations.

Nicknamed "aquatic pandas," Chinese sturgeon have existed for over 140 million years. However, the natural population of the species in the Yangtze plummeted in the late 20th century due to human activities.

In recent years, China has made significant conservation efforts, including expanding artificial breeding and release and fostering natural breeding of the species.

Efforts will be strengthened to improve the quantity and quality of captive Chinese sturgeon, continue large-scale restocking, and work toward restoring wild populations, according to the ministry.