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captivity as no such achievement has been reached previously (Liu et al., 2002; Wang et al.,
2005).
For having the porpoises successfully bred in captivity, their physiology status, such as
cycles of serum reproductive hormones have to be fully understood. We used to take blood
samples for physical status examination of the animals monthly, but this sampling rate is
insufficient for appropriately monitoring hormone levels. Therefore, we undertook veterinary
training and became proficient in the collection of feces, mouth saliva and blowhole secretion
everyday or even during every feeding time. We also established a laboratory protocol that
used feces to evaluate cycles of serum reproductive hormones. Meanwhile, their growths
were monitored monthly and behavior was observed daily. All of these results indicated that
the two animals that arrived in 1996 reached sexual maturity in 1999, and the animal that
arrived in 1999 reached sexual maturity in 2002. They started to mate at a very early age but
no confirmed copulation was recorded (Wei et al., 2004). Beginning in 2004, we physically
separated the females and the male for a short period in different two pools that are connected
by a water channel with a fence between them so they could communicate to each other
through this channel prior to ovulation without physical touching, and cancelled routine
physical examinations during ovulation in order to avoid disturbing the animals during this
sensitive period. We also petted the female's genital regions to stimulate sexual behaviors in
the females, making the females more accessible to the males during the breeding season
(Wang et al., 2005). After the males and females were reintroduced into the same pool, the
younger female became pregnant (introduced in 1999) and later gave birth to a male on July
5
th
, 2005. This represented the first freshwater cetacean ever born in captivity in the world (
Wang et al., 2005). This baby porpoise is still alive in captivity and in good health. On June 2,
2007, the same female gave birth to another male. Unfortunately, this female ate some cast
from the pool wall in which she lived, and consequently died 39 days later. Her second baby
also died 11 days later, even when we tried to feed him mixed milk. On July 5, 2008, the
elder female who was introduced in our pools in 1996, gave a birth to another male baby. But
for some unknown reason, she did not excrete milk for nursing, and the baby died 5 days
later.
F
UTURE
P
ROSPECT OF
C
ONSERVATION
Since China is still on its route of fast economic development, we cannot expect that the
Yangtze River's environment is going to improve in the near future, and it may get worse.
Under severe impacts caused by human activities in the Yangtze River, baiji is likely extinct
(Turvey et al., 2007). What we should do to prevent the Yangtze finless porpoise to become
the second baiji? Are there any ways to prevent this tragedy from happening again?
In general, in situ protection always comes first as a choice of conservation measures.
Even though the habitat of the Yangtze River has been degrading, we should first explore
every possibility to protect the Yangtze finless porpoise in its natural habitat. Fortunately, we
still have a relatively good number of the animals in the river and lakes, so it may provide us
a good base for us to carry out some measures to protect them.
Overfishing and illegal fishing of baiji and the Yangtze finless porpoise's prey are
blamed as some of the main reasons for causing the decline of both species (e.g.,D Wang et
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