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朱新全】 发表于 2015-09-25 09:08:00 点击: 【字体: 收藏

Hope Fading for China's Yangtze River Baiji Dolphin

Hope is fading for China's rare Yangtze River baiji dolphin after an international expedition failed to find a single baiji after almost two weeks of searching.

Scientists from six countries including China, the United States and Britain are despondent after their search in a national baiji dolphin reserve in Honghu Lake, in the central province of Hubei, failed to locate the mammal.

They now have their fingers and toes crossed that they will find some when they arrive Wednesday night at the Tongling National Freshwater Dolphin Reserve in the eastern province of Anhui.

Zheng Bangyou, director of the Tongling Reserve Administration, said they have a better chance of finding the baiji there as the reserve boasts a good ecosystem.

The team started the six-week search on Nov.8 inWuhan, a city on the middle reaches of the nation's longest river. The expedition will cover about 1,750 kilometers of the river up to Shanghai.

The scientists on two ships use high-powered binoculars and advanced acoustic equipment to detect the dolphin, dubbed "goddess of Yangtze River", and one of the world's 12 most endangered species.

Wang Ding, deputy director of the institute of hydrobiology under the Chinese Academy of Sciences, said he had seen with his own eyes 17 baiji dolphins during a 1980s research expedition, without any need for high-tech optical and acoustic equipment.

"Ten years ago or a little longer, I could see baiji quite often, but now it is headlines if I spot just one. The baiji is vanishing too fast, “said Zhang Zhongxiang, an elderly staffer at the baiji dolphin natural reserve in Honghu Lake.

According to estimates, less than 50 baiji dolphins, believed to be among the world's oldest freshwater mammals, are left, a sharp decline from about400 inthe early 1980s.

Some pessimistic experts put the number at 10.

Earlier media reports cited experts as saying that the baiji, a unique Chinese species living in the middle and lower reaches of Yangtze, might become the first whale species to go extinct if insufficient efforts were made to protect it.

Wang said it would be very hard for the species to survive if there are less than 20 left. The baiji only gives birth to one young a year.

"If we find one, we will do our utmost to trace it and capture it and then transfer it to a natural reserve for better protection," he added.

Experts blame worsening water pollution, increasing river traffic, illegal dynamite fishing and electrofishing for the sharp decline or possible extinction of the highly endangered species.

They said ships' engine noise can disturb the baiji's sonar system. The baiji relies on its highly developed sonar system instead of eyes.

Experts believe water conservation projects and toxic pesticide washed into the river from farmland have also taken their toll on the rare mammal.

China has worked out plans to transfer baiji to special reserves near the Yangtze to better protect the 25-million-year-old species, but as yet not a single specimen is in the reserves, according to Wang.

For the research team, the only good news is that they have found over 70 black finless porpoises, the baiji's Yangtze cousin. Porpoise numbers have also declined sharply over the past 20 years.

"We are doing more than just protecting the freshwater dolphins," said Wang, adding they also take water and silt samples every 50 to 100 kilometers of the river to monitor and later protect its deteriorating ecosystem.

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