Table 1.
Population status and distribution of Ganges river dolphin in the main stem of the Ganges River in India
| River | Segment | No. of Dolphin | Year | Reference | Remarks |
|---|---|---|---|---|---|
| Ganga | Between Haridwar and Middle Ganga Barrage at Bijnor (approx. 100 km) | 0 | December 1996 | Sinha et al. (2000) | The current upstream limit of the range of Ganges dolphins in the Ganges main stem appears to be below the Bijnor Barrage |
| Ganga | Between Bijnor and Narora Barrages (approx. 166 km) | 22/56 | 1993-95/2010 | Behera (1995)/Pers. comm. S. Behera | The isolated dolphin population between the two barrages appears to be increasing |
| Ganga | Between Narora and Kanpur (358 km) | 0 | 1997 | Sinha (1999) | Very low water in this stretch |
| Ganga | Between Kanpur and Allahabad (approx.252 km) | 98 | 2012 | Pers. comm. S. Behera | |
| Ganga | Allahabad to Buxar (approx. 425 km) | 204 (Downstream Survey) | 1997 | Sinha (1999) | |
| Ganga | Buxar to Maniharighat (500 km) | 808 (Upstream Survey) | 2006 | Sinha et al. (2010a) | The river has more water in this stretch as all the four major tributaries from Nepal discharge into the Ganges and create more hydro-geomorphological complexities |
| Ganga | Maniharighat to Farakka (approx. 70 km) | 115 (Downstream Survey) | 1998 | Sinha (1999) | |
| Ganga | Farakka Feeder Canal (38.2 km) | 21 (Downstream Survey) | 1996 | Sinha et al. (2000) | Farakka Barrage diverts regulated Ganges water to the River Bhagirathi through this canal |
| Bhagirathi | Jangipur to Triveni Ghat (320 km) | 119 (Downstream Survey) | 1995 | Sinha (1997) | Dolphin population is relatively low as the river receives regulated water with low silt resulting in low hydrogeological complexities |
| Hoogly | Triveni to Sagar Island (190 km) | 97 (Downstream Survey) | 2008 | Pers. comm. Gopal Sharma) | This tidal zone has high river traffic and large vessels |