Extinction of the Baiji Dolphin in China

The Baiji population declined drastically in recent decades as China industrialized and made heavy use of the river for fishing, transportation, and hydroelectricity. Efforts were made to conserve the species, but a late 2006 expedition failed to find any Baiji in the river. Organizers declared the Baiji "functionally extinct", which would make it the first aquatic mammal species to become extinct since the demise of theJapanese Sea Lion and the Caribbean Monk Seal in the 1950s. It would also be the first recorded extinction of a well-studied cetacean species (it is unclear if some previously extinct varieties were species or subspecies) to be directly attributable to human influence.


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 electric fishing, collisions with boats and ships, habitat loss, and pollution. During the Great Leap Forward, when traditional veneration of the Baiji was denounced, it was hunted for its flesh and skin, and quickly became scarce.[2]

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, boats grew in size, and fishermen employed wider and more lethal nets. Noise pollution caused the nearly blind animal to collide with propellers. Stocks of the dolphin's prey declined drastically in recent decades as well, with some fish populations declining to one thousandth of their pre-industrial levels.[14]

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."[2] Though outlawed, this 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.

Conservation Efforts

Soon after it decided to modernize, China recognized the precarious state of the river dolphin. The government outlawed deliberate killing, restricted fishing, and established nature reserves.

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. A breeding program would then allow the species to recover and be reintroduced to the Yangtze after conditions improve. However, capturing the rare, quick dolphins proved to be difficult, and few captives 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.


Conservation efforts of the Baiji along the Yangtze River

Since 1992 five protected areas of the Yangtze have been designated as Baiji reserves. Four were built in the main Yangtze channel where Baiji are actively protected and fishing is banned: two national reserves and two provincial. A fifth protected area is the Tian-e-Zhou Oxbow Semi-natural Reserve. Combined, these five reserves cover just over 350 kilometres (220 miles), about 1/3 of the Baijis range, leaving two-thirds of the species' habitat 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 re-emphasised 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.

In-situ Conservation

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

Ex-situ Conservation

In 1990 the first Finless Porpoises were relocated to the reserve and since then have been surviving and reproducing well. As of April 2005 26 Finless Porpoises were known to live in the reserve. A Baiji was introduced in December 1995, but 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. It has been reported that since the installation of this sluice gate, 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.

Done by Gabriel Wan 09s27

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