Yangtze River Dolphin Declared Extinct
The Yangtze river dolphin, or baiji, is functionally extinct, scientists from six nations said Wednesday after failing to find a single one of the rare animals after searching the river for six weeks.
The scientists blame destruction of dolphin habitat, illegal fishing and collisions with ships, dam building and environmental degradation for the extinction of this species once called the goddess of the Yangtze.
The 20 million year old river dolphin was one of the world's oldest species.
"It is possible we may have missed one or two animals," said August Pfluger, head of the baiji.org Foundation and co-organizer of the expedition. Regardless, these animals would have no chance of survival in the river."
"We have to accept the fact, that the baiji is functionally extinct. It is a tragedy, a loss not only for China, but for the entire world," said Pfluger.
The scientists conducted their search under the direction of the Institute for Hydrobiology Wuhan and the baiji.org Foundation, based in Switzerland.
Traveling on two research vessels 3,500 kilometers from Yichang near the Three Gorges Dam to Shanghai in the Yangtze Delta and back, the scientists sought the baiji with high performance optical instruments and underwater microphones.
The expedition was led by the Chinese Ministry of Agriculture and brought together experts from the Swiss Federal Institute of Aquatic Science and Technology, the U.S. National Oceanic and Atmospheric Administration, NOAA, the Hubbs-Seaworld Institute of San Diego, and Japan's Fisheries Research Agency.
In the early 1980s the Yangtze still had around 400 baiji swimming its waters.
A 1997 survey yielded 13 confirmed sightings. The last confirmed sighting of a baiji was in September 2004.
QiQi, a male baiji that was rescued in 1980, died in July 2002 at the Institute of Hydrobiology in Wuhan.
For more than 20 years baiji conservation was a hotly debated topic among Chinese and Western scientists who could not decide whether to leave them in their natural habitat or capture and move them to a safe place like the Tian-e-Zhou Oxbow Semi Natural Reserve.
"Now we do not have to discuss any longer," said Pfluger. "We have lost the race. The baiji has gone."
As they searched for the baiji, the scientists also surveyed the population of the endemic Yangtze finless porpoise, finding fewer than 400 of these animals.
"The situation of the finless propoise is just like that of the baiji 20 years ago," said Wang Ding, deputy director of the Institute of Hydrobiology in Wuhan. "Their numbers are declining at an alarming rate. If we do not act soon they will become a second baiji," he said.
The decline of the baiji and the critical situation of the finless porpoise do not appear to be directly influenced by the water quality of the Yangtze.
As part of the expedition, scientists from the Swiss Federal Institute of Aquatic Science and Technology investigated the chemical composition of the Yangtze river water and its particulate load. They took water and sediment samples from 30 locations along 1,750 kilometers of the river.
Although the Yangtze does have an altogether high degree of pollutant buildup, the institute's Beat Mueller said there are no indications of toxic pollutants in high concentrations.
The results of the water quality survey will be submitted to the Ministry of Agriculture next year.
Beside the Yangtze finless porpoise, four species of freshwater dolphins remain - three of them living in major freshwater systems in Asia. All of them are listed as critically endangered on the IUCNís Red List of Threatened Species.
Since the UN Environment Programme has declared 2007 to be the Year of the Dolphin, Pfluger believes the disappearance of the baiji must be seen as warning signal for the future. With the Ocean Park Foundation of Hong Kong, his foundation intends to organize a workshop on the conservation of Asian freshwater dolphins in Hong Kong.