Chinese fish experts released 100,000 artificially-bred young Chinese sturgeons into the Yangtze River near central China's Hubei Province on December 28 .

This is the first time China put into the river such a large number of young Chinese sturgeons measuring above 10 centimeters, in an effort to this rare endangered migratory fish species.

The Chinese sturgeon is known as a living fossil as it is one of the oldest vertebrates in the world. The rare fish migrates to the Jinshajiang River, a tributary of the Yangtze, from the sea and spawns there, and when the minnows grow to about 10 cm, they migrate back to the sea some 3,000 km away. As adults, they migrate back to the upstream to their birthplace.

But the fish now faces worsening living conditions due to the environmental pollution and illegal and rampant catching.

Experts say that the number of Chinese sturgeons that swim back to the Yangtze River every year has dropped to less than 1,000, with only some 500 of them able to spawn. They warned that the fish may become extinct in 50 years if no effective measures are taken immediately.

To save the endangered species, China has set up two large bases in Hubei to breed the fish, and from 1983 to 1998, nearly 6 million Chinese sturgeon minnows were released into the Yangtze. However, their survival rate is very low, as the minnows are mostly far less than 10 cm in length and they usually fall prey to other species of fish in the river.

Wei Qiwei, an expert with the Yangtze River Fishery Research Institute under the Chinese Academy of Fishery Science, said that the most effective way to increase the rare fish is to breed and release more young sturgeons measuring above 10 cm in length.

As to the success of the release this time, Wei added that there should be about 1,000 adult Chinese sturgeons migrating back to the Yangtze in 15 years even according to the lowest international standard.

Some of the minnows released Tuesday were labeled with various marks, including the coded wire tags imported from the US so as to make it easier to tell artificially-bred sturgeons from naturally-bred ones, he said.

To ensure a safe return for the young sturgeons to the sea, the Chinese Ministry of Agriculture has issued a notice, banning all kinds of fishing in the whole Yichang section of the Yangtze River between December 25 of this year and April 15 of next year.

Meanwhile, fishery departments along the river have intensified their crackdown on illegal fishing, especially the use of explosives, electric shocking devices and poisons.

Zhang Hecheng, deputy director of the Fishery Bureau of the ministry, said that relevant departments will trace the young fish 's migration all the way to the mouth of the Yangtze, and publicity will be launched to enhance the awareness of the public to protect the rare endangered fish and other wild marine species.

Yang Zhenhuai, vice-chairman of the Agricultural and Rural Affairs Committee of the National People's Congress, and Lu Ming, vice-minister of Agriculture attended today's releasing activities.