The Ganges River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are two sub-species of freshwater or river dolphins found in Bangladesh, India, Nepal and Pakistan. The Ganges River Dolphin is primarily found in the Ganges and Brahmaputra Rivers and their tributaries in India, Bangladesh and Nepal, while the Indus River Dolphin is only found in the Indus river in Pakistan. From the 1970s until 1998, they were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of a single species (see taxonomy below).
The species feeds on a variety of shrimp and fish, including carp and catfish. Dolphins are usually encountered on their own or in loose aggregations; they do not form tight, obviously interacting groups.
Both subspecies have been very adversely affected by human use of the river systems in the sub-continent. Entanglement in fishing nets can cause significant damage to local population numbers. Some individuals are still taken each year and their oil and meat used as a liniment, as an aphrodisiac and as bait for catfish. Irrigation has lowered water levels throughout both subspecies' ranges. Poisoning of the water supply from industrial and agricultural chemicals may have also contributed to population decline. Perhaps the most significant issue is the building of more than 50 dams along many rivers, causing the segregation of populations and a narrowed gene pool in which dolphins can breed. There are currently three sub-populations of Indus Dolphins considered capable of long-term survival if protected.
The immediate danger for the resident population of P. gangeticus in National Chambal Sanctuary is the decrease in river depth and appearance of sand bars dividing the river course into smaller segments.
Abundance and Prey Availability Assessment of Ganges River Dolphin (Platanista gangetica gangetica) in a Stretch of Upper Ganges River, India
Jan 01, 2010; Abstract The present study was conducted between January and June 2007 to assess the abundance and density of Ganges River...
Two Incidents of Fishing Gear Entanglement of Ganges River Dolphins (Platanista gangetica gangetica) in Waterways of the Sundarbans Mangrove Forest, Bangladesh
Jul 01, 2008; Abstract Incidental mortality in fishing gear, especially gillnets, is considered among the most severe threats to the endangered...