Ganges river dolphin

The Ganges river dolphin (Platanista gangetica) is a special kind of freshwater dolphin that lives in rivers. You can find it in the Ganges and other rivers in South Asia, especially in India, Nepal, and Bangladesh. People call it many names, like susu, shihu in Assamese, shushuk in Bengali in West Bengal and Bangladesh, and Uttum in the Chittagonian language in the Chittagong area.

This dolphin is very important to India. The Government of India chose it as the country's National Aquatic Animal, and it is also the official animal of the city of Guwahati. A long time ago, a person named William Roxburgh wrote about seeing the Ganges river dolphin for the first time in the Hooghly River.

Description

The Ganges river dolphin has a special, ridgelike back fin and females are often bigger than males. These dolphins can be tan, chocolate brown, dark grey, or light blue. They have long, slim noses with very sharp teeth, like most river dolphins. Their bellies are rounded, and together with their back fin, they look sturdy compared to sea dolphins. Their flippers and tail parts are large and wide.

These dolphins use a special part of their heads called a melon for echolocation because they do not see well in cloudy water, and their eyes are usually small. They are usually about 2.2 to 2.6 meters long, and the oldest one found was 28 years old.

Taxonomy

The Ganges river dolphin separated from the Indus river dolphin around 550,000 years ago. The oldest known fossil of this dolphin is about 12,000 years old.

Scientists first gave this dolphin a name, Delphinus gangeticus, in 1801. Two people described it, but we now know one of them shared his work just a little earlier. Later, in 1835, another scientist named it Platanista gangetica. For many years, people thought the Ganges and Indus river dolphins were the same species, but newer research shows they are two different species.

Etymology

The Ganges river dolphin has many different names where it lives. It is often called susu, but in Hindi it may be called soons, soans, or soos. In Bengali it is known as shushuk, and in Assamese it is called hiho or hihu. It is also named bhagirath after a character from Hindu mythology, and in Nepali it may be shus or suongsu. In old times, its Sanskrit name was likely shishumar, and during the Mughal era it was called pani suar.

Distribution

The Ganges river dolphin lives in rivers of Bangladesh, India, and Nepal. It likes deep pools, places where the water swirls, and areas near islands in the rivers.

A survey in 2025 found 6,324 Ganges river dolphins in India. Most were in the main part of the Ganges River, with some in smaller rivers that flow into it. Some also live in the Brahmaputra River and its smaller rivers.

Behaviour

The Ganges river dolphins usually swim alone or in pairs. They rarely jump out of the water and are shy around boats, making them hard to see.

These dolphins can use sounds to find their way and find food, even in very murky water. They make clicks and other short sounds to navigate and hunt. They can also make whistles, but this does not seem to be a way they talk to each other.

When a baby dolphin is born, it stays close to its mother for about one year. These dolphins find food by using sounds to locate creatures like small fish, shrimp, and even birds and turtles.

Threats

The Ganges river dolphin is listed as an Endangered species on the IUCN Red List. It faces many dangers, including having its home broken up by dams and changes in river flow. Dolphins can also get caught in fishing nets, which harms their populations. Pollution from cities and farms, as well as noise and traffic on the rivers, further threaten their survival. Sadly, some people still hunt these dolphins for their oil and meat, using it for medicines and bait for other fish. All these pressures have made it harder for the Ganges river dolphin to survive in its natural habitat.

Conservation

The Ganges river dolphin is protected from international trade by being listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. This means that people cannot buy or sell these dolphins across countries for money.

In India, the government is using old Hindu stories to help people care about saving the Ganges river dolphin. They also made a rule that dolphins cannot be kept in places for entertainment without special permission.

In 2020, India started "Project Dolphin" to help protect both river and ocean dolphins.

Bangladesh has created six special areas called sanctuaries in the Sundarbans to protect these dolphins.

Main article: Project Dolphin (India)

In culture

The Ganges dolphin is linked to the goddess Ganga. Sometimes, it is shown as her vahana, which is like a vehicle for the goddess. It is also connected to the makara, a mythical sea creature.