India’s Pink Secret: Why the Ganges is the only place to see the Amazon’s ‘long-lost’ counterpart

Why are these dolphins pink?

According to Encyclopedia Britannica, river dolphins get their pink hue from a variety of factors and biological characteristics. The mineral content of water bodies can affect their skin tone and diet, which can contribute to colour-changing pigments over time.

In many cases, dilation of blood vessels beneath the skin due to physical exertion also leads to a pink hue. Some river dolphins also turn pink as they age. While the young ones are grey and brown, their skin becomes mottled grey and pink with maturity, and some male dolphins turn bright pink.

Excessive social activity, such as play time or competitions, can increase their blood flow — similar to how humans blush or sweat and turn red. The shade also acts as a marker of health and vitality during mating.

A dead dolphin washed ashore near Malabar Hill in Mumbai. (Express Photo by Ganesh Shirsekar)

Unfortunately, the species faces a high risk of extinction due to human factors such as industrialisation, oil spills, poaching, and the fish trade. However, in good news, India’s largest river dolphin survey and the second range-wide estimation under Project Dolphin began two days ago in Bijnor, Uttar Pradesh.

According to the official statement released by the Ministry of Environment, Forest and Climate Change, the first phase of the survey will cover the main stem of the Ganga from Bijnor to Ganga Sagar and the Indus River. In the second phase, the survey will cover the Brahmaputra, the Ganga’s tributaries, the Sundarbans, and Odisha.

The previous nationwide survey (2021–23) recorded an estimated 6,327 riverine dolphins in India, including Ganges River Dolphins in the Ganga, Yamuna, Chambal, Gandak, Ghaghara, Kosi, Mahananda and Brahmaputra systems, and a small population of Indus River Dolphins in the Beas.

Uttar Pradesh and Bihar accounted for the largest numbers, followed by West Bengal and Assam, highlighting the critical importance of the Gangetic basin for long-term dolphin conservation. This serves as a powerful reminder that thriving rivers mean thriving aquatic and marine life.