Dolphins, Porpoises, and Whales - IUCN

Other Platanistoids
(Susu, Boto, Franciscana)
The other three platanistoid dolphins in addition to the baiji
and bhulan are not known to be critically endangered.
However, all three are exploited, their habitats are deteriorating
(especially those of the susu and boto), and much
scientific uncertainty surrounds their current conservation
status (especially that of the franciscana). Numerous projects
centered on these species were included in the previous
Action Plan, and some progress has been made (see
Table 2). Meetings held in 1992 (Reeves et al. 1993a, da
Silva and Marmontel 1994, Crespo 1994) provided conservation
and research recommendations that were used
as the basis for many of the projects on platanistoid dolphins
included in this Action Plan. It is felt that the
essence of "old" Projects 8 (Regional coordination of franciscana
research), 30 (Establishment of an Asian River
Dolphin Committee), and A15 was accomplished through
these meetings. However, it is important to stress the need
for continued financial and other support if the meeting
decisions and recommendations are to be implemented.
Specifically, the Asian River Dolphin Committee still
needs a focal center and a funding base. The Department
of Zoology at Patna University in Patna, India, has an
ongoing program to study and conserve the susu. Its geographical
position, institutional commitment, and history
of involvement make it a natural center for many of the
river dolphin committee's start-up activities. It is expected
that "old" Project 31 (Establishment of a Ganges river dolphin
project) will be at least partially realized through the
Patna program.
Whenever possible, projects should have multi-species
components that provide scope for cooperative effort and
financing in conjunction with other SSC specialist groups.
A model project of this kind, centered in Nepal and northern
India, was being developed by Brian D. Smith in late
1993 and early 1994.
Susu
Project 12
Estimate river dolphin populations in the Ganges,
Brahmaputra, Meghna, and Karnaphuli river systems
(including "old" Projects 22, 26,27, and A4)
Some of the work called for in the previous Action Plan
has been accomplished (Sinha 1992, Mohan 1992a,
Ahmed 1992, Dey et al. 1992, Mohan et al. 1993, Smith
1993, B.D. Smith and R.K. Sinha, pers. comm.; see
Reeves et al. 1993a), but there is still a critical need for
more and better information on the status and demography
of susus in many parts of India, Bangladesh, Nepal,
and Bhutan. The Asian River Dolphin Committee should.
i1
as one of its first goals, arrange for and supervise a complete
survey of susus throughout the four range states.
Since a number of investigators from different countries
will need to be involved (preferably working simultaneously),
it is important that they use standard survey
designs, methods, and terminology. A manual on susu surveying
techniques would be a useful tool for achieving
standardization. In advance of preparing such a manual,
several replicate upstream and downstream surveys should
be done of a single section of river within a short period
of time. This would provide some information on the variability
in direct counts or particular sampling schemes. It
has been suggested that the section of the Sarda River
(Mahakali in Nepal) between the Sarda Barrage in
Bonvasa and the Sarda Nagar Barrage might be an ideal
location for this set of surveys (B.D. Smith, pers. comm.).
Another component of the project should be an attempt
to investigate previously unsurveyed river systems such
as the Tista in Sikkim, the Manus in Bhutan, the Sangu in
Bangladesh, and the Mahanadi in India. Particularly in
downstream portions of the major river systems, it is
important to determine whether and how far other dolphin
species (e.g. finless porpoise, Irrawaddy dolphin) penetrate.
The presence of other species within a surveyed area
could confound results. This project should culminate in
an evaluation of the current status of all extant susu subpopulations
throughout the range of the species.
Project 13
Investigate ways of restoring river dolphin habitat
in the vicinity of Farakka Barrage, India (including
"old" Project 25)
Farakka Barrage, constructed in the early 1970s, created a
barrier to the movements of susus and other aquatic
wildlife between the lower reaches of the Ganges system,
including the biologically rich Sundarbans, and the middle
and upper Ganges (Jones 1982). Besides subdividing the
Ganges population of dolphins, the barrage has degraded
the riverine habitat, both upstream and downstream of the
structure; dolphins in the Feeder Canal between Farakka
on the Ganges and Jangipur on the Bhagirathi are said to
be especially vulnerable to capture in fishing gear (Ahsan
etal. 1992). Abetter understanding is needed of the physical
and biotic conditions that make habitat suitable for
river dolphins. Thus it would be appropriate for this project
to include studies of the characteristics of relatively
pristine dolphin habitat, for comparison with more compromised
habitat. Although it is recognized that all dams
and barrages constructed in areas inhabited by river dolphins
can have deleterious consequences for these animals
(see Projects 47 and 50), the strategic placement of
Farakka Barrage at approximately the geographic center of
the susu's total range gives it special significance. The aim