Tek Mahato Tharu grew up hearing stories from his grandfathers about the dolphins that used to inhabit the Narayani river in Nepal. However, as he got older, he couldn’t find any dolphins near his house and thought the stories were merely tales. Surprisingly, in the past two months, Mahato not only spotted the dolphins but also captured photographs, drawing attention to the long-awaited return of dolphins to the Narayani river.
According to Mahato, he heard rumors of dolphin sightings in Nepal, including the Narayani, in 2018. But it was only last year during a bird census that he personally witnessed two dolphins near the Bhelauji border point. Since then, he and others have observed dolphins multiple times in regions like Nawalpur, Amaltari, and Triveni, instilling a sense of pride and joy in witnessing the dolphins up close.
In addition to the Narayani river, dolphins have been sighted in various areas such as Nandpur, Golaghat, Amaltari, Pitaujighat, and Devghat. This resurgence of dolphins raises questions about the significance for Nepali rivers.
DB Chaudhary, a conservationist, echoes Tek Mahato Tharu’s sentiments, having seen the dolphins in the Amaltari area. He recalls how dolphins were a common sight in the Narayani river about 40 to 50 years ago, and he would eagerly visit the river to catch a glimpse of them. However, their population drastically declined over the past decade, with only one or two sightings. Fortunately, in the last five or six years, dolphin sightings have become more frequent.
A dolphin conservation action plan formulated by the Department of National Parks and Wildlife Conservation highlights the alarming global decline of Asian river dolphins. The plan cites a 2017 assessment indicating less than 5,000 Asian river dolphins worldwide, including 3,500 Ganges subspecies. A separate study conducted in 2016 estimated the presence of around 60 to 50 dolphins in Nepal.
The Ganges river dolphin, scientifically known as Platanista gangetica, is a freshwater dolphin inhabiting the Ganges-Brahmaputra-Meghna and Karnaphuli-Sangu river systems in Nepal, India, and Bangladesh. It represents one of the few remaining species of freshwater dolphins. These dolphins possess distinctive physical characteristics such as a long, pointed snout, a low triangular dorsal fin, and small eyes positioned on the sides of their heads, resulting in poor eyesight but excellent hearing and echolocation abilities.
Known for their social nature, Ganges river dolphins are often found in groups of two to ten. They are active swimmers, occasionally leaping out of the water. Echolocation plays a crucial role in their navigation and foraging, as their diet primarily consists of fish and crustaceans. The population of these dolphins serves as an indicator of the overall health of river ecosystems.
These dolphins exhibit a preference for areas that create countercurrents, such as small islands, sandbars, river bends, and convergent tributaries. During the monsoon season, they migrate locally to tributaries and then return to larger river channels during the dry winter season.
The decline in the dolphin population in Nepal can be attributed to various factors. The IUCN Red List of Threatened Species classified the Ganges river dolphin as endangered in 1996 due to a decline in its population throughout its distribution range. Habitat loss, pollution, overfishing, and increased tourism activities have all contributed to the decrease in dolphin numbers. Conservationist DB Chaudhary emphasizes that multiple factors, including climate change and its cascading impacts, have led to the decline in sightings.
Human intervention is identified as a significant threat to dolphins. Dams constructed in rivers, including the Triveni barrage on the Narayani-Gandak river, impede the dolphins’ ability to swim against the river flow and reach their usual habitats. The IUCN has recognized this issue as a hindrance to dolphin movement and habitat preservation. Other threats to the species and marine life in general include illegal fishing practices and the use of nets that unintentionally trap dolphins and other larger species. Addressing these challenges is vital for the conservation of dolphins.
To ensure the long-term survival of dolphins, it is essential to expedite conservation efforts in Nepal. Although it is uncertain whether the dolphins sighted in various locations are the same individuals, DB Chaudhary urges the acceleration of conservation measures to prevent another loss of these mammals from Nepal’s waters.
Nepal’s Dolphin Conservation Action Plan (2021-2025), devised by the Department of National Parks and Wildlife Conservation, aims to assess the conservation status of dolphins, prioritize conservation efforts, identify key issues, reduce human-induced pressures on aquatic habitats, and implement viable action plans to secure the species’ long-term survival.
Additionally, Chaudhary emphasizes the need for a comprehensive water conservation policy in Nepal. This policy should focus on mitigating human intervention, reducing water pollution levels, and understanding its impacts on dolphins. Advocacy at all levels, along with raising awareness among locals and individuals involved in fish farming, is crucial for the protection of dolphins and their habitat.