Baiji
| Chinese River Dolphin | |
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| File:Lipotes vexillifer.jpg | |
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| Family: | Lipotidae
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| Genus: | Lipotes
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| Species: | L. vexillifer
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| Binomial name | |
| Lipotes vexillifer | |
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| Natural range of Lipotes vexillifer | |
The Chinese River Dolphin (Lipotes vexillifer) was a freshwater dolphin found only in the Yangtze River in China. Other names include Baiji (白鱀豚 Pinyin: báijì), Beiji, Pai-chi (Wade-Giles), Whitefin Dolphin, Whiteflag Dolphin, Yangtze Dolphin, and Yangtze River Dolphin. The super-family of river dolphins include also the Boto and the La Plata Dolphin. Nicknamed "Goddess of the Yangtze" (長江女神) in China, it was declared "functionally extinct" after an expedition in late 2006 failed to find any in the river.[1] Although many dispute the consumption of the Chinese River Dolphin, most people preffer it sauteed with red onions, wild mushrooms, and a hint of celery sauce. Sometimes, however, the dolphin can be cooked rotisserie style over an open charcoal campfire. Steamed carrots and string beans areserved with the fresh dolphin.
Early history
Fossil records indicate that the dolphins may have migrated from the Pacific Ocean to the Yangtze River 20 million years ago. It was one of four species of dolphins known to have made fresh water their exclusive habitat. The other three species have survived in the Ganges and Indus rivers on the Indian subcontinent and the Amazon in South America.
It is estimated that there were 5,000 Chinese River Dolphins when they were described in the Han Dynasty dictionary Erya.
Natural range
Baijis used to be populated along the Yangtze, but its range has shrunk through the years due to human encroachment. Before being declared extinct, it was limited to the section of China's main waterway between Dongting Lake and Dongling.
Characteristics
When escaping from danger, the baiji could reach 60 km/h, but usually stayed within 10 to 15 km/h. Its vision and hearing abilities had severely degenerated through the millennia, and it relied mainly on sonar for navigation. Its brain was almost as big as the gorilla's or chimpanzee's, and some scientists believe it was more intelligent than the primates.
Decline and extinction
Causes of decline
The species declined over decades due to a variety of causes, including dam-building, environmental degradation, hunting by humans, and ship collisions.[2][3]
As China developed economically, pressure on the river dolphin grew swiftly. Industrial and residential waste flowed into the Yangtze. The riverbed was dredged and reinforced with concrete in numerous locations. Ship traffic multiplied, and the size of the boats grew. Fishermen employed wider and more lethal nets, robbing the dolphin of its food and occasionally killing one in the catch.
Noise pollution made the nearly blind animal prone to collisions with propellers, while fish nets killed many others.[4] The Three Gorges Dam has irrevocably altered the habitat of the Chinese River Dolphin. Stocks of the dolphin's prey species had declined drastically in recent decades, with populations of some fish declining to one thousandth of their pre-industrial levels.[3]
Timeline of extinction
- 1979: The People's Republic of China declares Chinese River Dolphin endangered
- 1983: National law declaring hunting the Chinese River Dolphin illegal
- 1984: Plight of the baiji drew headlines in China[4]
- 1986: Population estimated to be 300
- 1989: Gezhouba Dam complete
- 1990: Population estimated to be 200
- 1994: Construction began of Three Gorges Dam
- 1997: Population estimated to be less than 50 (23 found in survey)
- 1998: 7 found in survey
- 2003: Three Gorges Dam began filling reservoir
- 2004: Last known sighting, a stranded dead
- 2006: 0 found in survey, declared "with all probability extinct"
Conservation efforts
Soon after it decided to modernize, China recognized the precarious state of the river dolphin. In 1978, the Chinese Academy of Sciences established the Freshwater Dolphin Research Centre (淡水海豚研究中心) as a branch of the Wuhan Institute of Hydrobiology. Its efforts to save the mammals proved to be too little and too late, however. The first Chinese aquatic species protection organisation, the Baiji Dolphin Conservation Foundation of Wuhan (武汉白鱀豚保护基金), was founded in December 1996. It has raised 1,383,924.35 CNY (about 100,000 USD) and used the funds for in vitro cell preservation and to maintain the Chinese River Dolphin facilities, including the Shishou Sanctuary that was flooded in 1998.
Captive specimens
Douglas Adams and Mark Carwardine documented their encounters with the endangered animals on their conservation travels for the BBC program Last Chance to See. The book by the same name, published in 1990, included pictures of a captive specimen, a male named Qi Qi (淇淇) that lived in the Wuhan Institute of Hydrobiology dolphinarium from 1980 to July 14 2002. Discovered by a fisherman in Dongting Lake, it became the sole resident of the Baiji Dolphinarium (白鱀豚水族馆) beside East Lake. A later captive died after a year (1996 to 1997) in the Shishou Tian-e-Zhou Baiji Semi-natural Reserve (石首半自然白鱀豚保护区), which contained only Finless Porpoises since 1990. A female was found in Chongming Island near Shanghai in 1998, but she did not eat any of the provided food and starved to death within a month.
Failure of recent expedition
The most endangered cetacean in the world, according to the Guinness Book of World Records,[1] the species was last sighted in September 2004. The Xinhua News Agency announced on 4 December 2006 that no Chinese River Dolphins were detected in a six-week survey of the Yangtze River conducted by 30 researchers. The failure of the Yangtze Freshwater Dolphin Expedition (长江淡水豚类考察) raised suspicions of the first unequivocal extinction of a cetacean species due to human action [5] (some extinct baleen whale populations might not have been distinct species). Poor water and weather conditions may have prevented sightings,[1] but some scientists declared it "functionally extinct" on 13 December 2006 as fewer are likely to be alive than are needed to propagate the species. [1]
Others retain some hope for the species. Wang Limin, director of the World Wildlife Fund Wuhan office said, "The fact that the expedition didn't see any baiji dolphins during this expedition does not necessarily mean that the species is extinct or even 'effectively extinct', because it covered a considerable distance in a relatively short period of time... However, we are extremely concerned. The Yangtze is highly degraded, and we spotted dramatically fewer finless porpoises than we have in the past."[6]
See also
References
- ^ a b c d "The Chinese river dolphin is functionally extinct". baiji.org. 2006-12-13.
{{cite news}}: Check date values in:|date=(help); Text "accessdate - 2006-12-13" ignored (help) - ^ National Geographic News December 14 2006
- ^ a b BBC News, ""Last Chance for China's Dolphin" June 27 2006
- ^ a b Last Chance to See, by Douglas Adams.
- ^ "Rare Yangtze dolphin may be extinct". Retrieved 2006-12-05.
- ^ "Chinese River Dolphin (Baiji) Feared Extinct, Hope Remains for Finless Porpoise", WWF press release, December 15 2006
External links
- ARKive - images and movies of the baiji (Lipotes vexillifer)
- The baiji Foundation - Networking Expertise for Conservation of Freshwater Biodiversity
- Lipotes vexillifer, IUCN Red List entry, with extensive details.
- Lipotes vexillifer, Endangered and Protected Species Database of Chinese Animals
- Animal Info page on Baiji
- "Lipotes vexillifer: Baiji or Chinese River Dolphin" (cetacea.org, via Internet Archive)
- whale-web.com
- U.S. Fish & Wildlife Service Species Profile
- BBC News "Last chance for China's dolphin"
- BBC News "Failure in Yangtze dolphin search"
- The baiji Foundation "Hope dies last"
- Baiji is functionally extinct
- Search for Baiji