Some artificially bred Chinese sturgeons were released into the Yangtze River on Friday, the waterway where this aquatic species has lived for 140 million years.

This means that we have worked out a method to artificially breed this rare aquatic species, making it possible for us to protect this living fossil fish from extinction at least for the foreseeable future.

Chinese sturgeon used to travel nearly 3,000 kilometers to the upstream of the Yangtze to lay eggs. But, starting from the 1980s, dams built along the river made it impossible for it to continue to do this.

Scientists concluded then that it was possible that such sturgeons could develop the habit of laying eggs in waters around the Gezhouba Dam in the middle reaches of the river when they could no longer travel further upstream. They did. But the damming of river water by the Three Gorges Dam three years ago has possibly damaged the environment for sturgeons to lay eggs in the waters near the Gezhouba Dam.

The successful artificial breeding of this fish in the 1980s made it possible for the fish to survive without breeding in the river.

It also suggests that our efforts to mitigate the negative impact of tapping the resources of the river have paid off.

About 6 million artificially bred Chinese sturgeons of different ages and sizes have been released into the river since 1981.

The negative message is that our human activities have destroyed the natural environment for quite a number of wild species, including Chinese sturgeons. It is fortunate that we have succeeded in artificially breeding Chinese sturgeons. If we had failed, such species would have already become extinct. Some, such as the Baiji Yangtze dolphin, another rare aquatic species in the river, are believed to have become extinct.

Can humanity coexist peacefully with other species? It seems that humanity is only able to explore natural resources and develop for its own benefits at the cost of other species.

Scientists estimate that more than 800 species have become extinct because of human activities over the past 500 years, and even more will disappear at a far faster rate in the near future unless we do something.

The artificial breeding of Chinese sturgeons and giant pandas is a step we have taken to maintain biodiversity, albeit a passive one. We need positive steps to protect wild species.

(China Daily April 21, 2007)