Price of shark fins is up to 4,000 yuan (about 600 U.S. dollars) per kilogram, said Huang Liming, duty manager at the medium-level Hongxing Seafood Restaurant in southern Guangzhou city. Shark fins could be sold up to 10,000 yuan per kilogram in upscale restaurants, Huang said.

But sales of shark fins have declined 30 percent recently from a year earlier to at most 0.5 kilogram each day as people prefer healthier and environmental-friendly food, Huang said, adding most of the delicacy is consumed by businessmen.

"People are mistaken by the supposed nutritional value of shark fin," Ding said.

"Research shows the nutritional value of shark fin is similar to that of poultry, fish skin, meat and eggs. It is tasteless and its low level nutritional value is hard to absorb by the body." He said.

Further, it contains high levels of lead and mercury, which most people know little about, he said, adding he neither eats shark fins nor treats guests with the dish.

Ding proposed that governmental officials take the lead in stopping the consumption of shark fin, and that state-owned hotels and restaurants stop serving shark fin.

Ding, ranking the 25th in 2009 Hurun Steel Rich List with 1.5 billion yuan of wealth, is a member of China Entrepreneur Club, which joined with the Wildaid, an international NGO, to launch a champaign in Beijing in 2009 to call on the public to protect sharks and reject shark fins.

Zhang Xingsheng, managing director of North Asia Region of The Nature Conservancy (TNC), started an online poll on microblog website of Sina.com since Jan. 8, calling on the country's legislature to ban overall shark fin trading.

As of Wednesday, 27,370 people have voted for the ban, and 440 voted against the ban.

"Sharks are killed for their little piece of fins. The damage to them..., we all understand", said a netizen called "Shuizhongdemancao".

But some netizens do not favor the ban. A netizen dubbed "Dingnandn" said, "people think it is cruel to kill sharks, but is it not cruel to kill pigs, bulls and sheeps? Are they born to be eaten by human being? The proposal of the ban comes out of a sudden sense of guity of those who don't eat shark fins. If so, we should ban all meat eating! It is very environmental friendly!"

"Although the shark fin soup is delicious..., it should be banned....," a netizen named "Jiajia77" said after voting for the ban. "The advertisment aired on TV countless times a day is really shocking", she said.

In December 2009, the Wildaid enlisted NBA star Yao Ming to appear in non-profit advertisement, urging to stop sales of shark fins.

"When the buying stops, the killing can too," he said in the video ad.