POPULATION STATUS AND CONSERVATION OF THE GANGES RIVER DOLPHIN (PLATANISTA GANGETICA GANGETICA) IN THE INDIAN SUBCONTINENT - Biology, Evolution and Conservation of River Dolphins Within South America and Asia - page 429

Table 2. Continued.

The Betwa (from
confluence of the
Yamuna at Hamirpur to
Orai

84 km 06 (d/s survey) Sinha et al (2000)

The Sind (from
confluence with the
Yamuna)

110 km 05 (d/s survey) Sinha et al (2000)

The Son 130 km 10 (d/s survey) Sinha et al (2000)

The Brahmaputra 600 km

856 km

400 (1996)
197 (2004-05)

Mohan (1997)
pers. comm. A. Wakid (2006)

The Barak River 17 km 12 (Nov. 1999)

8 (2004)
6 (2006)

Pers. comm. Paulan Singh

The Subhansiri River 99 km 26 pers. comm. A. Wakid(2006)

The River Kulsi 76 km 27 pers. comm. A. Wakid(2006)

In Bangladesh

The Jamuna 189 km 38-50 Smith et al (1998)

The Kushiyara 113 km 34-43 Smith et al (1998)

The Burhi Ganga 03 Smith et al (1998)

The Karnaphuli-Sangu 222 km 131 Smith et al (2005)

The Sundarbans 1488 km 225 Smith et al (2005)

In Nepal

The Karnali (from
Kachali to Kotiaghat)

60 km 06 Smith et al (1994)

The Saptakosi (from
confluence of Arun and
Sun Kosi to Kosi
Barrage)

60 km 03 Smith et al (1994)

The Narayani (Devghat
to Triveni Barrage)

1-2 Smith et al (1994)

The Mahakali Nil Smith et al (1994)

In the Brahmaputra River system the susu are present as far north-east as the Dihang,
Buri Dihing and Lohit rivers in eastern Assam, and as far north as the Teesta River and its
tributaries, which extend into Sikkim and Bhutan (Mohan, 1989). The population status in
different rivers in its distribution range, based on surveys conducted by different workers in
the last two decades has been depicted in Table 2. The survey methods adopted by different
workers were not consistent and therefore there is a lack of scientifically credible population
estimates for this species. Nevertheless, the estimated total dolphin population in its fairly
extensive distribution range is about 2500.
During the dry season, when the water levels are low in the rivers, the dolphins stay in
the main river channels, however, they stay back in the deep pools in the tributaries also,
where they face threats of being caught in the fishing nets as such pools attract intensive
fishing. During the monsoon season, they spread out and move into even smaller tributaries
and creeks. There are more dolphins at confluences, meanderings, and behind sand bars,
where counter currents and complex hydro-geo-morphological formations exist. Such
complexities provide habitats for diversified biota in the river ecosystems.