Current Status of the Endangered Ganges River Dolphin (Platanista Gangetica), the Aquatic Megafauna in the Brahmaputra River System

Abstract

The Ganges River Dolphin (Platanista gangetica) is the most charismatic aquatic species inhabiting rivers of India, Bangladesh, and Nepal. It is an endangered species that occurs both in the Brahmaputra and Barak river systems in Assam (India). In the Brahmaputra river system, the occurence of ‘hihu’ is primarily confirmed in the mainstream Brahmaputra, the Kulsi river of Kamrup district, and the Subansiri river of Lakhimpur district. The dolphins inhabit river confluences or tributary junctions followed by river meanderings with the prevalence of eddy counter-currents and prey-fish abundance. Of late, it has been observed that river dolphin population has declined at an alarming rate due to the potential threats including poaching for dolphin oil, by-catch, overfishing, net entanglements, sand mining, habitat destruction through aquatic pollution, construction of dams, and lack of awareness. The species is left only in certain pockets of the Brahmaputra River. Thus, there is an urgent need for the conservation of this endangered species in its natural habitats. Effective protection of this endangered aquatic megafauna requires elimination and management of the potential threats. This review provides an overview of the distribution and population status, ecology, and management strategies and recommendation to increase awareness for its long-term conservation.