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vessel traffic in protected river sections or to patrol these sections frequently (Zhou et al.,
1998); indeed, it is unlikely that vessel traffic would ever have been controlled within China
on the basis of environmental concerns alone, given the Yangtze's importance as the ‗Golden
Channel' in supporting large-scale national economic development in recent decades (D.
Wang et al., 2006). Similar problems also continue to surround effective management of
pollutant release into the river channel, with negligible control of point and non-point
pollution sources (Dudgeon, 2005). Furthermore, wider questions over whether protection of
limited river sections could ever provide adequate conservation for baiji were raised by
ecological observations and photo-identification studies of wild baiji, which indicated that
although individual animals may stay in the same restricted geographical area for up to a
month, they could also make migrations of more than 200 kilometers up and down the
Yangtze channel, with anecdotal information provided by fishermen supporting the idea of
large-scale seasonal movements (Zhou et al., 1994, 1998; Zhang et al., 2003). Survey data
interpreted by Zhou et al. (1998) suggested that even the Xin-Luo Reserve section would only
be inhabited by six baiji at any one time, and at least some of these animals would move
between protected and adjacent non-protected areas, making
in situ
conservation efforts of
limited usefulness.
Because of these potentially insurmountable obstacles to effective conservation of baiji in
their natural habitat, more intensive species-specific recovery strategies also received
considerable attention from both Chinese and international conservation practitioners. As
early as the late 1970s, Pilleri (1979) noted the potential for conserving baiji through captive
breeding, which he considered would represent ‗a splendidly original achievement'. This
approach was soon also widely supported within China. Between 1980 and 1986, six baiji
were brought into captivity at the Institute of Hydrobiology, Chinese Academy of Sciences
(four individuals), Nanjing Normal University (one individual) and the Jiangsu Aquatic
Institute (one individual) (Zhou & Zhang, 1991; Chen et al., 1997). However, only two of
these animals survived for more than a few months, and reproductively viable male and
female individuals were never maintained in captivity together (the only captive female baiji
died before reaching sexual maturity; Zhou &
Zhang, 1991). It therefore remains impossible
to assess whether successful reproduction could have eventually been achieved under these
conditions (contra Yang et al., 2006), especially because Yangtze finless porpoises have now
bred successfully in the modern well-equipped dolphinarium at the Institute of Hydrobiology
(Wang et al., 2005). Although the official view within China appears to have increasingly
supported placing baiji into this dolphinarium in recent years (Dudgeon, 2005),
ex situ
baiji
conservation under strict captive conditions received little support from the international
conservation community (Braulik et al., 2005) other than Japan (Chen & Liu, 1992), even
given the marked international advances in captive cetacean maintenance, welfare and
husbandry that have been achieved in recent decades. ‗Qi Qi', a male baiji that survived in
captivity at the Institute of Hydrobiology for over 22 years, displayed stereotypical behaviour
(Dudgeon, 2005), and it is unlikely that animals bred and maintained for long periods under
such circumstances could have been successfully reintroduced into the wild, or even whether
Chinese authorities and research staff would have permitted such a move given the national
importance attached to any institution possessing captive individuals. Attempts to
cryopreserve sperm from captive baiji also proved unsuccessful.
The alternative
ex situ
conservation strategy that was widely promoted by both Chinese
and international conservationists was the establishment of a translocated breeding population
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