Baiji

iBaiji
Conservation status
Critically endangered (CR), possibly extinct
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Subclass: Eutheria Order: Cetacea Suborder: Odontoceti Superfamily: Platanistoidea Family: Lipotidae Genus: Lipotes Species: L. vexillifer
Binomial name
Lipotes vexillifer Miller, 1918
Natural range of Lipotes vexillifer

The Baiji Lipotes vexillifer, Lipotes meaning "left behind", vexillifer "flag bearer") was a freshwater dolphin found only in the Yangtze River in China. Nicknamed "Goddess of the Yangtze" (長江女神) in China, the dolphin was also called Chinese River Dolphin, Yangtze River Dolphin, Beiji, Pai-chi (Wade-Giles), Whitefin Dolphin and Yangtze Dolphin. It is not to be confused with the Chinese White Dolphin (中華白海豚).

Although efforts were made to conserve the baiji after its population declined drastically in recent decades, the species was declared "functionally extinct" after an expedition in late 2006 failed to find any in the river.

Early history

Fossil records indicate that the dolphin may have migrated from the Pacific Ocean to the Yangtze River 25 million years ago. It was one of four species of dolphins known to have made fresh water their exclusive habitat. The freshwater dolphins include 3 other species: the Boto and the La Plata Dolphin of the Rio de la Plata and Amazon in South America and the Ganges and Indus River Dolphin.

It is estimated that there were 5,000 Chinese River Dolphins when they were described in the ancient dictionary Erya circa 3rd century BC. A traditional Chinese story describes the Chinese River Dolphin as the reincarnation of a princess who had been drowned by her family after refusing to marry a man she did not love. Regarded as a symbol of peace and prosperity, the dolphin was nicknamed the "Goddess of the Yangtze."

Natural range

Historically the Baiji occurred along 1,700 kilometres (1,000 miles) of the middle and lower reaches of the Yangtze from Yichang in the west to the mouth of the river, near to Shanghai. This has been reduced by several hundred kilometres both upstream and downstream, and now is limited to the main channel of the Yangtze, principally the middle reaches between the two large tributary lakes, Dongting and Poyang. This decline in habitat is partly due to the construction of the Three Gorges Dam but mainly because approximately 12% of the world’s human population live and work within the Yangtze River catchment.

Physical description

Mature Baijis were about 2.3 metres (7.5 ft) long in males and 2.5 metres (8 ft) in females, the longest measured at 2.7 metres. They weighed 135-230 kilograms (300-510 lb), with a lifespan estimated at 24 years in the wild. Males reach sexual maturity at age four, females at age six. They are thought to have bred in the first half of the year, with the peak calving season from February to April. A 30% pregnancy rate was observed. Gestation period was 10-11 months, with one calf delivered at a time; the interbirth interval was 2 years. Calves measured around 80-90 centimetres (32-35 in) at birth, and nursed for 8-20 months.

When escaping from danger, the Baiji could reach 60 km/h, but usually stayed within 10 to 15 km/h. Because of its poor vision and hearing, the baiji relied mainly on sonar for navigation.

Decline of the species

In the 1950s, the population was estimated at 6,000 animals, but declined rapidly over the subsequent five decades. Now the most endangered cetacean in the world, according to the Guinness Book of World Records, the Baiji was last sighted in September 2004.

Causes of decline

The World Conservation Union (IUCN) has noted the following as threats to the species: a period of hunting by humans during the Great Leap Forward, entanglement in fishing gear, the illegal practice of Electrofishing, collisions with boats and ships, habitat loss, and pollution.

During the Great Leap Forward, when traditional veneration of the Baiji as "Goddess of the River" was denounced, it was hunted for its flesh and skin, and it quickly became scarce.

As China developed economically, pressure on the river dolphin grew significantly. Industrial and residential waste flowed into the Yangtze. The riverbed was dredged and reinforced with concrete in many locations. Ship traffic multiplied, the size of the boats grew, and fishermen employed wider and more lethal nets. Noise pollution made the nearly blind animal prone to collisions with propellers. Stocks of the dolphin's prey had declined drastically in recent decades as well, with some fish populations declining to one thousandth of their pre-industrial levels.

In the 1970s and 1980s, an estimated half of Baiji deaths were attributed to entanglement in fishing gear. By the early 2000s, electric fishing was considered "the most important and immediate direct threat to the Baiji's survival." Though outlawed, the destructive fishing technique is widely practiced throughout China. The building of the Three Gorges Dam further reduced the dolphin's habitat and facilitated an increase in ship traffic.

Timeline

• circa 3rd century BC: population estimated at 5,000 animals
• 1950s: population was estimated at 6,000 animals
• 1958-1962: The Great Leap Forward denounces the animal's traditional venerated status
• 1979: The People's Republic of China declares the Chinese River Dolphin endangered
• 1983: National law declares hunting the Chinese River Dolphin illegal
• 1984: The plight of the Baiji draws headlines in China
• 1986: Population estimated to be 300
• 1989: Gezhouba Dam complete
• 1990: Population estimated to be 200
• 1994: Construction of the Three Gorges Dam begins
• 1996: IUCN lists the species as critically endangered
• 1997: Population estimated to be less than 50 (23 found in survey)
• 1998: 7 found in survey
• 2003: Three Gorges Dam begins filling reservoir
• 2004: Last known sighting, a stranded dead dolphin
• 2006: None found in survey, declared "with all probability extinct"

Surveys

Results of Yangtze River Baiji surveys between 1979 and 1996 ( * Lower reaches only)

Year	Survey Area	No. of km surveyed	No. of Baiji sighted	No. of Baiji estimated
1979	Wuhan-Chenglingji	230	19	-
1979	Nanjing-Taiyangzhou	170	10	-
1979-1981	Nanjing-Guichi	250	3-6 groups	400
1978-1985	Yichang-Nantong	1600	>20 groups	156
1985-1986	Yichang-Jiangyin	1510	42 groups	300
1979-1986	Fujiangsha-Hukou	630	78-79	100*
1987-1990	Yichang-Shanghai	1669	108	200
1989-1991	Hukou-Zhenjian	500	29	120
1991-1996	Xinchang-Wuhan	413	42	<100

Conservation efforts

Soon after it decided to modernize, China recognized the precarious state of the river dolphin. The government made deliberate killing illegal, placed some restrictions on fishing, and established nature preserves.

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. In the 1980s and 1990s, several attempts were made to capture dolphins and relocate them to a reserve. The strategy was to set up a breeding program, allow the species' numbers to recover, improve conditions in the Yangtze, and then reintroduce the species. However, capturing the rare, quick dolphins proved to be difficult, and no captured dolphins survived more than a few months.

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 Baiji facilities, including the Shishou Sanctuary that was flooded in 1998.

File:Baiji conservation efforts map.png

Conservation efforts of the Baiji along the Yangtze

Since 1992 five protected areas of the Yangtze have been designated as National or Provincial Baiji reserves. Four of these are in the main Yangtze channel where Baiji are actively protected and fishing is banned: the Shishou City and Xin-Luo National Baiji Reserves and the Tongling and Zhenjiang Provincial Baiji Reserves. A fifth additional protected area is an isolated oxbow lake located off of the north bank of the river near to Shishou City: the Tian-e-Zhou Oxbow Semi-natural Reserve. Combined, these protected areas cover just over 350 kilometres (1/3 of the Baijis range) meaning that 2/3 of the species habitat is unprotected.

As well as these five protected areas there are also five “Protection Stations” in Jianli, Chenglingji, Hukou, Wuhu and Zhengjiang. These stations consist of two observers and a motorised fishing boat with the aim of conducting daily patrols, making observations and investigating reports of illegal fishing.

In 2001 the Chinese government approved a Conservation Action Plan for Cetaceans of the Yangtze River. This plan reemphasised the three measures identified at the 1986 workshop and was adopted as the national policy for the conservation of the Baiji. Despite all of these workshops and conventions little money was available in China to aid the conservation efforts. It has been estimated that US$1 million was needed to begin the project and maintain it for a further 3 years.

Efforts to save the mammals proved to be too little and too late. August Pfluger, chief executive of the Baiji.org Foundation, said, "The strategy of the Chinese government was a good one, but we didn't have time to put it into action."

In-situ conservation

Most scientists agree that the best course of action is an ex-situ effort working in parallel with an in-situ effort. The deterioration of the Yangtze River must be reversed to preserve the habitat. The ex-situ projects aim to raise a large enough population over time so that some, if not all, of the dolphins can be returned to the Yangtze, so the habitat within the river must be maintained anyway.

Ex-situ conservation

The Shishou Tian-e-Zhou is a 21 kilometre long, 2 kilometre wide oxbow lake located near Shishou City in Hubei Province. Shishou has been described as being “like a miniature Yangtze … possessing all of the requirements for a semi-natural reserve”. From the designation as a national reserve in 1992 it has been intended to be used for not only the Baiji but also the Yangtze Finless Porpoise. In 1990 the first Finless Porpoises were relocated to the reserve and since then have been surviving and reproducing well. As of April 2005 there are known to be 26 Finless Porpoises in the reserve. In December 1995 a Baiji was introduced but she died during the summer flood of 1996. To deal with these annual floods a dyke was constructed between the Yangtze and Shishou. Now water is controlled from a sluice gate located at the downstream mouth of the oxbow lake. However there have been reports that since the installation of this sluice gate the water quality has declined since no annual transfer of nutrients can occur. Roughly 6,700 people live on the ‘island’ within the oxbow lake and so some limited fishing is permitted.

Success of Shishou with the porpoises and with migratory birds and other wetland fauna has encouraged the local Wetlands Management Team to put forward an application to award the site Ramsar status. It has also been noted that the site has incredible potential for ecotourism, which could be used to generate much needed revenue to improve the quality of the reserve. The necessary infrastructure does not currently exist to realize these opportunities.

Captive specimens

A Baiji conservation dolphinarium was established at the Institute of Hydrobiology (IHB) in Wuhan in 1992. This was planned as a backup to any other conservation efforts by producing an area completely protected from any threats, and where the Baiji could be easily observed. The site includes an indoor and outdoor holding pool, a water filtration system, food storage and preparation facilities, research labs and a small museum. The aim is to also generate income from tourism which can be put towards the Baiji plight. The pools are not very large (25 m arc [kidney shaped] x 7 m wide x 3.5 m deep, 10 m diameter, 2 m deep and 12 m diameter, 3.5 m deep) and so are not capable of holding many Baijis at one time.

Douglas Adams and Mark Carwardine documented their encounters with the endangered animals on their conservation travels for the BBC programme 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 sexually mature female was captured in late 1995, but died after half a year in 1996 when the Shishou Tian-e-Zhou Baiji Semi-natural Reserve (石首半自然白鱀豚保护区), which had contained only Finless Porpoises since 1990, was flooded.

Details of captive baijis
(IHB = Institute of Hydrobiology, NNU = Nanjing Normal University, NFRI = Nanjing Fisheries Research Institute)

Name	Date range	Location	Sex	Conditions of rearing	Survival time
Qi Qi	1980-01-12 - 2002-07-14	IHB	M	Outdoor & indoor, non-filtered	22.5 years
Rong Rong	1981-04-22 - 1982-02-03	IHB	M	Outdoor non-filtered	228 days
Lian Lian	1986-03-31 - 1986-06-14	IHB	M	Outdoor non-filtered	76 days
Zhen Zhen	1986-03-31 - 1986-06-14	IHB	F	Outdoor non-filtered	2.5 years
Su Su	1981-03-03 - 1981-03-20	NNU	F	Indoor	17 days
Jiang Jiang	1981-12-07 - 1982-04-16	NFRI	M	Outdoor non-filtered	129 days

2006 expedition

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 (some extinct baleen whale populations might not have been distinct species). Poor water and weather conditions may have prevented sightings, 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.

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."

See also

• Chinese paddlefish
• Chinese sturgeon

External links

Wikimedia Commons has media related to: Lipotes vexillifer

• ARKive - images and movies of the Baiji (Lipotes vexillifer)
• Lipotes vexillifer, IUCN Red List entry, with extensive details.
• The Baiji Foundation - Networking Expertise for Conservation of Freshwater Biodiversity
• 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
• Lipotes vexillifer, Endangered and Protected Species Database of Chinese Animals

News

• 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

References

• Adapted from the Wikipedia article, "Baiji" http://en.wikipedia.org/wiki/Baiji, used under the GNU Free Documentation License