Biology Reference
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al., 1998, 2000, 2005, 2006; K Wang et al., 2006). Meanwhile, fish production of the Yangtze
River has been decreasing from its high of 427,000,000 kg in 1954 to approximately
100,000,000 kg in recent years, even with a much more intense fishing effort (Wei et al.,
2007). This warns that fish resources of the river are almost dried up. But, annual freshwater
fish aquaculture production of the whole country is quite high at approximately
21,000,000,000 kg (Wei et al., 2007) in recent years. This means that fish production of the
Yangtze River plays a relatively minor role for the fishery economic development. On the
other hand, fish germplasm of the Yangtze River is the best overall in the country (Wei et al.,
2007). For protecting fish resources in the river, the Chinese government has been prohibiting
any fishing activity in the middle and lower reaches of the Yangtze River from April 1 to the
end of June each year since 2003. Even though this measure may have improved the status of
fish resources in the river (Wei et al., 2007), it is still far away from solving the problem, as
fisherman may just simply spend more time and much effort on fishing right after the period
to compensate their loss during fishing ban period and because there may be more fish for
fishing, and any improvement of fish resources could be destroyed right away. For protecting
fish resources in the river to benefit aquiculture development and Yangtze cetacean
protection, we suggest that fishing should be forbidden year-round in the whole river. In the
least, fishing should be forbidden in each reserve. Furthermore, because the disconnection
between river and lakes within the middle and lower reaches of the Yangtze River has
directly resulted in decreasing of fish recourses (Wei et al., 2007), re-establishing linkage
between the Yangtze River and its appended lake clusters could greatly improve the habitat
status of fish resources of the river, which could greatly help the conservation of the Yangtze
finless porpoise.
We already established some natural reserves in the river and lakes that cover almost
every hot spot of the animal distribution (Figure 1). But, most of the reserves are in many
challenging areas since the river is being used by many kinds of human activities, and they
can do little for managing most of them. For example, we can't expect to stop transportation
in the river that is blamed to be very harmful for the baiji and the porpoise (Chen et al., 1997;
D. Wang et al., 1998, 2000). In this case, some regulations have to be worked out and put into
practice to at least control navigation. We suggest that the speed of every ship passing the
reserve should be limited, possibly below 10 km/h and that blasting cannot be used to deepen
and widen the shipping channel in the reserve.
The demonstration of Tian-e-Zhou reserve proves that ex situ is a possible way to
establish a sustainable population of the Yangtze finless porpoise. It provides a possibility
that we could establish additional off site protected populations of the porpoise for assuring
long term survival of it in nearly natural habitats, such as in other similar oxbows of the
Yangtze River. A systematic survey should be done soon to investigate these sites to select
some as other semi-natural reserves for the porpoise. Meanwhile, after the Three-Gorges Dam
was finished, the water current above the dam is much slower than it was before which was
the main restriction to effectively block the porpoise from the upper reaches of the Yangtze
River. We suggest that the huge reservoir above the dam should be explored for the
possibility of establishing a population of the Yangtze finless porpoise. Should this occur, it
could provide another reliable solution for saving the Yangtze finless porpoise.
Some progresses have been made on captive breeding. Even we cannot expect that
captive breeding can solve all of the problems (Wang et al., 2005), we should consider
expanding the captive colony to establish a possible sustainable group. While doing so, much
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