Home fragmented by barrages
Previous Population and DistributionDuring the last century, thousands of freshwater dolphins rolled and jumped in their natural habitat, which once ranged throughout the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems of Nepal, India, and Bangladesh, from the Himalayan foothills to the Bay of Bengal. In 1982, the population in India was estimated to be between 4,000 and 5,000 individuals. Today, it is difficult to sight a dolphin in the rivers.
Extensive modifications of this species' habitat have reduced its once abundant population throughout its range. The distribution in the Ganges has diminished by approximately 100 km (62 miles) since the 19th century, with hundreds of kilometres of tributary habitat lost to irrigation barrages. There has been a concomitant reduction in water flow.
Current Population and Distribution
Today the population has a much reduced range, and is divided by dams into isolated groups. The lowest estimate for the total population is 1,200–1,800 individuals.
Although the population size has decreased compared to historical levels, it is still considered to be large enough to sustain the species in the future if adequate conservation measures are taken soon.