India's First National River Dolphin Count Found 6,327 Dolphins in 28 Rivers Across Eight States, With 2,397 in Uttar Pradesh and 2,220 in Bihar, Where the Vikramshila Sanctuary Protects 60 km of the Ganga

India’s first national count of river dolphins estimated 6,327 of them in 28 rivers across eight states, in a report the Prime Minister released on 3 March 2025, according to the Press Information Bureau (PIB). The survey covered more than 8,500 km of river and took 3,150 man-days of fieldwork, and the report came out at the seventh meeting of the National Board for Wildlife at Gir in Gujarat. The field work ran from 2021 to 2023, a later PIB release says.

The report is published by the Environment Ministry and the Wildlife Institute of India (WII) in Dehradun. Its estimate of 6,327 comes with a range of 5,980 to 6,691, WII’s brochure says, and it is made up of 6,324 Ganges river dolphins (Platanista gangetica) and 3 Indus river dolphins in the Beas river in Punjab.

A national animal since 2009

The Ganges river dolphin lives in fresh water and river mouths and never enters the open sea. Locals call it susu. A 2025 review by researchers at the Indian Council of Agricultural Research’s Central Inland Fisheries Research Institute and the National Mission for Clean Ganga describes it as nearly blind, finding its way with high-frequency clicks and their echoes.

In the 1870s its range covered a linked network of rivers across southern Nepal, Bangladesh and India, from the Himalayan foothills to the Sundarbans delta, the review says. PIB’s 2026 release lists today’s Indian strongholds as the Ganga, Yamuna, Chambal, Gandak, Ghaghara, Kosi, Mahananda and Brahmaputra systems, and PIB’s March 2025 backgrounder puts about 90 percent of the global population in India.

India named it the National Aquatic Animal at the first meeting of the National Ganga River Basin Authority on 5 October 2009, the Bihar Forest Department records. The review adds that the formal recognition followed in May 2010.

It sits in Schedule I of the Wild Life (Protection) Act, 1972, which the review calls the strongest protection the Act gives and which prohibits hunting. PIB says an amendment in December 2022 recognised the Gangetic and Indus river dolphins as distinct species within Schedule I. The review adds that the International Union for Conservation of Nature (IUCN) lists the Ganges river dolphin as Endangered.

What the first count found, state by state

WII’s brochure gives Uttar Pradesh 2,397 dolphins, Bihar 2,220, West Bengal 815, Assam 635, Jharkhand 162, Rajasthan and Madhya Pradesh together 95, and Punjab 3. Those seven figures add up to 6,327, and PIB records the same order for the top four. By river system, the Ganga main stem held 3,275 and its tributaries 2,414. The Brahmaputra main stem held 584 and its tributaries 51, a split a Rajya Sabha reply of August 2026 also gave, as The Sentinel reported.

In Assam, All India Radio reported, the survey found a barrier-free Brahmaputra population consistent with WII’s 2020 estimate, and the report suggests it has been stable.

Bihar’s 2,220 and the Vikramshila sanctuary

Bihar’s 2,220 dolphins were counted along 1,368 km, an encounter rate of 1.62 dolphins per km. Among the seven state rows only Jharkhand’s, 162 dolphins over 59 km, is higher at 2.75. By tuput’s sum Bihar holds 35 percent of the national figure. Our Bihar state profile covers the rest of the state.

The Vikramshila Gangetic Dolphin Sanctuary was notified in 1991 under the 1972 Act and covers 60 km of the Ganga from Sultanganj to Kahalgaon in Bhagalpur district, the Bihar Forest Department says. It is named after the ruins of Vikramshila University, a Buddhist centre of learning in the Pala period. Because the river shifts its channel, the department says, the sanctuary’s boundary and extent keep changing.

The 2025 review names it as the sanctuary devoted to the species. It cites an earlier study that found as many as 1.8 dolphins per km inside the sanctuary, and suggests the complete fishing ban there may explain the higher rate. Fishers in Bhagalpur also take part in a Dolphin Mitra (dolphin friend) initiative, Mongabay India reported in August 2022.

How a river dolphin gets counted

Ganges river dolphins spend very little time at the surface, PIB notes, so a count has to allow for animals that are present but unseen. WII’s brochure says the survey used boat-based visual surveys with the independent double observer method, plus underwater microphones called hydrophones. A Rajya Sabha reply described the same two parts as visual surveys and passive acoustic monitoring.

The brochure says the design was meant to deal with two problems it names, observer bias and availability bias. Two observers on the boat record sightings independently, and the overlap between their lists shows how many animals a single observer misses. The hydrophones pick up the dolphins’ clicks, so an animal that stays under as the boat passes can still be detected.

WII analysed the data with the Lincoln-Petersen formula in Chapman’s corrected form and with the Huggins method, which are statistical ways of estimating the total from what was seen. The reasoning is close to the camera-trap logic in our piece on how India counts its tigers and lions, and the 5,980 to 6,691 range plays the same role as the tiger range does there.

Project Dolphin since 15 August 2020

PIB records that Project Dolphin was launched on 15 August 2020, the day of the Prime Minister’s Independence Day speech. ETV Bharat reported on that day that it was planned as a 10-year project in line with Project Tiger and Project Elephant, with modern tools for counting dolphins and checking poaching, and with work to raise the incomes of fishing communities. PIB describes its aim as protecting marine and river dolphins through habitat protection, scientific research and community awareness.

PIB’s March 2025 backgrounder lists what followed. A Comprehensive Action Plan for 2022 to 2047 was finalised. The Project Dolphin Steering Committee, reconstituted, held its first meeting on 6 September 2023. The Union scheme for developing wildlife habitats allocated Rs 241.73 lakh (about Rs 24 million) for dolphin conservation activities in 2022-23 and Rs 248.18 lakh in 2023-24.

On 18 December 2024 WII, with the Assam Forest Department and the Assam conservation group Aaranyak, satellite-tagged a Ganges river dolphin in Assam, the first of its species ever tagged this way, which PIB calls a global first in dolphin conservation. The same March 2025 board meeting also announced a new project for gharials, the long-snouted crocodilians covered in our piece on the gharial’s comeback.

What protects the dolphin, and the work still ahead

PIB says the Chambal river has a 200 km stretch in Madhya Pradesh, Rajasthan and Uttar Pradesh recommended for designation as a dolphin conservation zone. The Rajya Sabha was told in August 2026, The Sentinel reported, that a project approved for funding through National CAMPA, the authority that manages compensatory afforestation money, covers 131 districts across nine states and includes rescue and rehabilitation, capacity building and ecological monitoring.

The 2025 review lists the threats as dams and barrages, restricted river flows, entanglement in fishing nets, pollution, sand mining and vessel collisions. Water quality and river flow are covered in our piece on the Ganga clean-up. The survey itself marked two places for attention: the Beas, where 3 Indus river dolphins were estimated, and Assam’s tributaries, where All India Radio reported no sightings in the Barak and a fall in numbers in the Subansiri.

A second survey using the same method began at Bijnor in Uttar Pradesh on 17 January 2026, with 26 researchers in three boats. Its first phase covers the Ganga main stem from Bijnor to Ganga Sagar and the Indus river, and its second phase covers the Brahmaputra, the Ganga tributaries, the Sundarbans and Odisha, where it will also estimate Irrawaddy dolphins.