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Endemic Dolphin "Extinction" Mirrors Yangtze Health Decline
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An international expedition that recently declared the Yangtze River dolphin, or 'baiji' (literally translated as 'white fin') "functionally extinct" has aroused public attention to the environmental degradation of China's longest waterway.


Over a six-week period between November and December 2006, and equipped with high performance optical instruments and underwater microphones, the team of scientists cruised on two research vessels over 3,500 kilometers from Yichang near the Three Gorges Dam to Shanghai in the Yangtze Delta, and back.


"The moment that experts disembarked from the ships, was the moment that humankind bid farewell to the 20-million-year-old baiji," said Wang Kexiong, an expert working with the Institute of Hydrobiology (IHB), based in Wuhan, "the baiji can easily be spotted as they breathe on the surface and splash water almost every 30 seconds. It's a traditional and effective way to locate a baiji."


Dubbed 'Goddess of the Yangtze', the baiji was held in high regard by the ancient peoples of the Yangtze, who believed that the white 'fish', the same size of a human being, could help safeguard sailing.


In the early 1980s, the Yangtze reportedly 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.


As the expedition returned to land having failed to sight a single baiji, August Pfluger, head of the Baiji.org Foundation and co-organizer of the expedition, pronounced the species "functionally extinct" as there are likely to be fewer alive than are needed to stop the species dying out.


Nevertheless, Chinese experts say they will continue to search for the mammal in the Yangtze's waterways. International standards state that, in order for a species to be declared extinct, no sighting of it has to be reported for between 20 to 50 years.


Most of the scientific world's knowledge of the species comes from 'QiQi', a male baiji that was rescued by the IHB in 1980 and died in 2002. Wang Kexiong who, along with his colleagues, had been taking care of QiQi, conceded that with his death in 2002, many people probably lost their last chance to cast eyes on the quickly vanishing species.


"The Baiji is very friendly to humankind -- even though he had sharp teeth, QiQi would never attack people standing nearby. If he was unhappy with us, he would simply tap us with his tail -- at 2.5 meters long and weighing in at 200kg, QiQi could have given us a much more powerful whack if he had wanted to," said Wang.


Wang added that, "The baiji has feelings and thoughts, just like other mammals -- we could sense QiQi was lonely at times but he was relatively happy when people were in his company. It's just a pity we failed to find him a mate -- the baiji usually lives in a nuclear family."


Wang Kexiong expressed his concerns for the future of the Yangtze's entire ecological system stating that, "Cetaceans (whales, dolphins and porpoise) live at the top of the food chain -- if they are threatened by extinction, it means that their food sources are also dwindling and biodiversity in the Yangtze River is degenerating."


The water quality in the Yangtze has changed remarkably along with China's economic growth, the increase in shipping, coupled with the dumping of waste in the river has polluted the river.


According to experts however, the most obvious threat posed to the existence of the cetaceans is the rampant sand-dredging activities that are being practiced along the river's course.


The Yangtze, its tributaries and lakes are covered with sand-dredging ships -- there are about 12 sand-loaded ships for every kilometer of the Yangtze. However, a survey carried out by the expedition estimated that the number of ships per kilometer in the lower reaches of the river could top 30 to 60.


Commenting on the huge impact that the dredgers have upon the two species, Wang Kexiong said, "The noise pollution in the air is already a torture for humankind, let alone for sound-sensitive cetaceans underwater. It makes the baiji prone to collisions with ship propellers and prevents them from finding a mate, hunting and communicating with the peers."


Depletion of riverbed sand also destroys the habitats of other animal and plant life that call the river home.


The Chinese government has been tightening measures to forbid sand dredging in the main channel of the Yangtze, however local governments are continuing to issue permits for dredging in the river's tributaries and surrounding lakes.


"A ship-full of sand yields a profit of at least 100,000 yuan (12,500 U.S. dollars) -- more than enough to drive thousands of people into the business," Wang says.


The Yangtze River basin is home to 400 million people, roughly a third of China's total population -- all of whose waste ends up being dumped into the river.


According to the State Environmental Protection Administration, the amount of wastewater discharged into the Yangtze has shot up by almost two thirds -- from 11.39 billion tons in 1998 to 18.42 billion tons in 2005.


Weng Lida, an expert with the Yangtze Valley Water Resources Protection Bureau, commented how the pollution endangers some 500 city drinking-water sources along the river. "Many cities and towns fail to treat sewage properly -- merely 15 percent of domestic sewage is treated properly before being discharged into the river," Weng said.


"There are about 1,133 lakes in the middle and lower reaches of the river," said Wang Ding, deputy director of the IHB, "all of these, except the Dongting Lake, are equipped with dams, sluice gates, bridges or reinforced banks." Wang then went on to explain how these dams and sluice gates have robbed the baiji of their normal habitat and cut off the migration routes of fish on which they feed.


The expedition team collected water and sediment samples along the route of river. Swiss experts will analyze the samples and submit the results to the Chinese later this year.


"The results might be gloomy," said Wang, "the Yangtze pollution is serious. Discharge from a thermal industrial plant could produce a steaming river section for several kilometers, whilst discharge from paper mills or chemical plants could cover some sections with a thick, multi-colored layer of scum."


What next?


Biodiversity has been dwindling in the river. Surveys show that in the mid-1980s, the Yangtze was home to some 126 animal species, however, by 2002 that number had fallen to just 52 -- primarily due to the widespread level of pollution that has occurred in the river, according to Lu Jianjian, a professor with the East China Normal University.


Since 2003, a closed fishing season has been brought into effect along the course of the Yangtze River in a bid to recover fish resources. Despite this, the situation has not improved.


Cao Dongsheng, a fisherman from Yueyang County in Hunan Province told China Features, "20 years ago -- by using traditional fishing methods -- we could harvest 100kg of fish every day." Cao added that today, "There are little fish left in the river, as people are making use of poisons, electric fishing, and illegal fishing nets."


Ecological and environmental degradation of the Yangtze has made experts worry about the fate of yet another of the river's inhabitants'-- the Yangtze finless porpoise, known locally as the 'jiangzhu'(literally 'river pig').


Wang Ding commented that, "The situation of the Yangtze finless porpoise is just like that of the baiji 20 years ago." He added, "Their numbers are declining at an alarming rate -- if we do not act soon they will soon follow the baiji down the road of extinction."


According to the IHB, there are currently 1,200 to 1,400 jiangzhu swimming in the waters of the Yangtze -- roughly half the number that were estimated in 1991.


"The government has been shifting from GDP-oriented development to sustainable development, but the task of safeguarding the environment and improving the enforcement of environmental laws is still challenging," said Wang Kexiong.


Commenting on the future of the river's ecosystem, Wang declared, "The Yangtze is a river of life -- if we go on harming its health, it might well turn into river of death."


(Xinhua News Agency January 22, 2007)

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