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of baiji under semi-natural conditions, in a protected environment away from the main river
where human impacts could be closely managed and minimized compared to the degraded
Yangtze channel. This approach was therefore more similar to translocation of insular species
to predator-free offshore islands than to traditional
ex situ
propagation in artificial facilities.
The semi-natural reserve strategy first received serious consideration in the published
literature by Lin et al. (1985), and was pursued independently by the two Chinese research
groups actively working on baiji in the 1980s. The research group at Nanjing Normal
University initiated a project to create a semi-natural reserve in a 1550-meter channel
between Heyuezhou Island and Tiebanzhou Island near Tongling in 1985 (Zhou, 1986, 1989).
The Institute of Hydrobiology's Baiji Research Group had already begun surveying the mid-
lower Yangtze to identify suitable semi-natural reserve sites in 1984 (Chen & Liu, 1992), and
proposed the establishment of a reserve at Tian'e-Zhou (a 21 kilometer oxbow near Shishou
which formed part of the main Yangtze channel until 1972) at the Workshop on Biology and
Conservation of the Platanistoid Dolphins in 1986 (Baiji Research Group, 1989; Zhang et al.,
1995). Both sites were developed into potential baiji reserves, but attention both within China
and from the international community soon focused on the Tian'e-Zhou oxbow as the more
suitable prospective site for a semi-natural baiji population, and this was designated as a
National Natural Reserve for baiji conservation by the Chinese Ministry of Agriculture in
1992 (Zhou et al., 1994; Braulik et al., 2005).
A translocated population of Yangtze finless porpoises introduced to the oxbow from
1990 onwards, as a surrogate to test the suitability of the reserve for baiji, began to breed
successfully in 1992, suggesting that conditions were also favorable for introduced baiji to
survive and breed (Wang et al., 2000). However, despite assurances by regional authorities
that fishing and associated human impacts would be strictly controlled at Tian'e-Zhou, 30%
of the reserve budget is still met by income from fishing in the reserve, and only 200 of the
500 fishermen have been moved away from the area and provided with alternate livelihoods,
leading to continued serious problems of competition for fish resources and the dangers of
accidental by-catch of translocated cetaceans (Dudgeon, 2005; pers. obs.). Indeed, two
translocated porpoises have been killed by rolling hook long-lines in the reserve, two other
animals died from injuries associated with their capture and translocation, a further seven
animals were killed accidentally in the reserve by inexperienced researchers, and fourteen
escaped during the flood season of 1996; despite this high level of mortality, fifteen more
animals were released back into the Yangtze to reduce competition for fish with local
fishermen operating in the reserve (Zhou et al., 1994; Wang et al., 2000). The continued
presence of porpoises in the reserve also led to ongoing concerns from international
conservationists about possible risks to any translocated baiji from agonistic interactions and
competition for limited food resources between the two species (Zhou et al., 1994; Braulik et
al., 2005; Dudgeon, 2005; Yang et al., 2006). Recommended on-site infrastructural
improvements, e.g. cetacean holding pens to allow effective post-translocation health
monitoring and veterinary care before soft-release into the reserve, were also never
adequately adopted (Figure 5). Only one baiji was ever translocated to the Tian'e-Zhou
oxbow, in December 1995, and was found dead of unknown causes a few months later,
emaciated and entangled in fence nets in a region of strong current (Liu et al., 1998). No
further attempts were made to capture baiji for translocation to Tian'e-Zhou, although
subsequent unsuccessful capture efforts to establish a baiji population at the Tongling semi-
natural reserve continued until 2001 (Tongling Provincial Baiji Reserve staff, pers. comm.,
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