Ganges River dolphin: an overview of biology, ecology, and conservation status in India

Abstract

Ganges River dolphin, Platanista gangetica gangetica, is one of the three obligatory freshwater dolphins in the world and is distributed in the Ganges-Brahmaputra-Meghna and Sangu-Karnaphuli River systems in India, Nepal, and Bangladesh. This species is facing considerable threats to its survival, and its population has dwindled from 4000 to 5000 in the early 1980s to 3500 in 2014 in the distribution range. This article reviews current status of the sub-species, habitat use, and the potential threats that the dolphins face for their survival (details of taxonomic status and genetics, evolutionary adaptations and anatomical peculiarities, physical adaptation, primitive characteristics, biology, behavior, surfacing behavior and dive times, mating and birth, and life span/age have been placed as Electronic Supplementary Materials). Recommendations have been made for the protection and developing strategies for the conservation of this Endangered and endemic sub-species.

Fig. 1

The Ganges River basin in India

Fig. 2

Distribution map of Platanista gangetica in the 1870s (Anderson 1879) and 2009; red highlight on the left panel indicates the historical distribution range

Fig. 3

A sand bar (3 km × 0.3 km) in the head pond of Farakka Barrage along the Ganges River in December 2004

Fig. 4

Platanista gangetica gangetica surfacing in the River Ganges (Photo by Fernando Trujillo)