Biology Reference
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of Chinese people living in the basin - home to approximately 10% of the world's human
population. The Yangtze River is also called ―golden channel‖ of the country, which means it
plays very important role for development of the country. Although reserve management staff
may try very hard to lessen harmful human activity impacts on the baiji and the Yangtze
finless porpoise they are overwhelmed because many of these human activities are still on-
going, and worse, expanding on a great scale. For example, transportation through the Three
Gorges Dam was 147,500,000 tons (t) in 2003, and it reached 439,300,000 t in 2005 (Yi et
al., 2007), the number tripled in three years. The number of boats in the river has increased
approximately five-fold since the late 1980s (Wang et al., 2006). Futhermore, during a survey
between Yichang and Shanghai in 2006, a minimum of 19,830 large shipping vessels were
counted, which translates into more than one ship per hundred meters of river (Turvey et al.,
2007). Because of over fishing and habitat loss, fish production of the Yangtze River has been
decreasing remarkably (Wei et al., 2007). In contrast, the influx of sewage into the Yangtze
River has significantly increased from 9,500,000,000 t/a at the end of the 1970s, to
15,000,000,000 t/a at the end of the 1980s, and it reached 29,640,000,000 t/a in 2005 (Wu &
Tu, 2007). While protective regulations for the baiji and Yangtze finless porpoise and their
habitats are in place, effective enforcement is an immense problem in such a huge river, in a
densely populated area of a developing country. For example, even though some harmful
fishing gears are listed as illegal, they have never-the-less been used frequently (Turvey et al.,
2007). Therefore, these reserves may help to slow down the process of extinction of both the
baiji and the Yangtze finless porpoise, yet they cannot prevent the occurrence of harmful
human activities. Unfortunately, the success of in situ conservation is highly limited (Wang et
al., 2006; Turvey et al., 2007).
Establishment of Semi-Natural Protected Populations
The conditions in the Yangtze River are considered highly unlikely to be improved in the
foreseeable future, which make the outlook for the barely surviving baiji and finless porpoise
populations in the river bleak. We have to seek some other ways to help the porpoise before
they become extinct. As early as in middle 1980s, our research group started to search for a
place to set-up semi-natural reserve to establish an ex situ protected population of the
porpoise. Tian-e-Zhou Oxbow (Figure 1), an old course of the Yangtze River, lies in the north
bank of the river in Shishou County, Hubei Province of China. This oxbow used to be a
section of the Yangtze River, and was cut off from the main stem of the river naturally in
1972. It is approximately 21 km long and 1 - 2 km wide. Zhang et al. (1995) made a
systematic investigation on its water quality, biological productivity, and fish production etc.,
and concluded that the oxbow is ideal as a semi-natural habitat for the finless porpoise. The
first group of 5 finless porpoise, 3 females and 2 males, were captured in the Yangtze River,
and released in the oxbow in 1990 (Table 1). Since then, several more groups of Yangtze
finless porpoises have been captured or rescued from the river and also transplanted into the
oxbow. The animals have been left to live in the oxbow freely without the intervention of any
factitious variable. For example, no artificial feeding is needed. The result confirms that these
animals can not only survive, but can also reproduce naturally and successfully in this
reserve. Approximately two calves are born each year, with at least 29 babies born in the
reserve by the end of 2007 (Table 1). Accounting that some animals have moved, died
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