(ECNS) - Fishery resources in the Yangtze River are declining rapidly, both in terms of diversity of species and their numbers, as efforts have failed to halt overfishing, the Economic Information Daily reported Monday.
Cao Wenxuan, fish expert and academic at the Chinese Academy of Sciences, said the environment for aquatic life in China's longest river was at a "critical point."
He urged the government to replace the current annual fishing ban with a more rigorous ten-year moratorium to allow the remaining populations to recover.
The current ban, extended from three months to four months this year, covers the spawning season for most of the river's aquatic life. It includes the entire river as well as key tributaries and lakes.
The Yangtze River is the most valuable reserve of aquatic bio-diversity in China. Data showed that more than 1,100 aquatic species live in the river, including more than 370 fish species. The river is also home to endangered species under national protection.
Cao said five rare species have already become extinct and two more - Chinese sturgeon and river dolphin – are on the brink of extinction as fishing stocks depleted dramatically in recent years.
Wang Ding, a researcher with the Institute of Hydrobiology at the Chinese Academy of Sciences, said the ecological environment in the Yangtze River has deteriorated and some species simply die from hunger.
Experts say genetic diversity has worsened compared to times past, with sample fish caught in many sections of the river "smaller in size, less suitable to the environment and weaker in terms of disease resistance."
The biggest threat to China's top species-rich river is overfishing, followed by habitat loss amid rapid economic growth. There used to be more than 30 billion fry in the 1950s, but now the number is only 100 million, according to Cao.
Cao and his team found that new and powerful hunting measures used by fishermen had accelerated the loss of fish in the middle and lower Yangtze River.
Xie Songguang, also a researcher with the Institute of Hydrobiology, said a study at Dongting Lake, which is connected to the river, found that 91 percent of fish caught were less than 50 grams. He said this overexploitation at unsustainable rates would certainly affect fish reproduction.
China has introduced a slew of laws and regulations to ban overfishing, including the annual finishing ban initiated in 2002 and other measures such as releasing fish fry. But their implementation and results seem to be far from enough to improve the situation.
Cao and other fish experts said the ten-year ban would reverse the trend of ecological degradation and also bring significant economic benefits.
He said provinces could help fishermen find other job opportunities by offering training or hiring them as protectors of the river's fishing resource. Currently, there are about 280,000 fishermen and 62,000 fishing boats on the Yangtze River and its key tributaries.
