China says 16 endangered finless porpoises have been found dead since the beginning of the year and experts blame water pollution and climate change for pushing the species toward extinction.

The freshwater porpoise -- popularly known in Chinese as the "river pig" -- mainly lives in China's Yangtze River and two lakes linked to the waterway.

Authorities have discovered 10 dead porpoises in Dongting Lake in the central province of Hunan since March, said a statement Thursday by the government of Yueyang city, which is located on the lake's shore.

Another six dead porpoises have been found in Poyang Lake in the eastern province of Jiangxi since the beginning of the year, the official Xinhua news agency said late Wednesday.

It quoted experts as warning the species will be extinct within a matter of years.

Wang Kexiong, a researcher at China's Institute of Hydrobiology, said water pollution, shipping, sand dredging and illegal fishing were all possible contributing factors to the recent deaths.

Many waterways in China have become heavily contaminated with toxic waste from factories and farms -- pollution blamed on more than three decades of rapid economic growth and lax enforcement of environmental protection laws.

The report said climate change also could be to blame as disrupted weather patterns have caused water levels to drop and make it more difficult for the porpoises to find food.

Tests have shown that some of the porpoises are believed to have died of starvation, it said.

In 2006, China was estimated to have only 1,200 finless porpoises left. That same year, the Baiji -- a freshwater dolphin also native to the Yangtze River -- was declared extinct.

Earlier this year, a survey found just 65 "river pigs" in Dongting Lake and 300-400 in Poyang Lake, the report said.

Following the recent deaths, Yueyang city vowed to investigate and increase protection of the remaining porpoises in Dongting Lake.