Irrawaddy dolphin

How it lives

The Irrawaddy dolphin lives in shallow coastal waters, estuaries, mangroves and a few big rivers and lakes, rarely far from shore. It is slow and shy, rarely leaps and often avoids boats. It can spit jets of water from its mouth, which seems to help it herd fish. In the Ayeyarwady River of Myanmar, cast-net fishers and dolphins have a documented partnership: fishers tap their boats, and dolphins herd fish and signal with their tails.

Where it goes

Most groups stay in the same river stretch, lagoon or coast all year. In the Mekong, dolphins use deep pools in the dry season along about 120 to 180 km of river between Kratie and Stung Treng in Cambodia. The last dolphin of the Cambodia and Laos border pool died on 15 February 2022, and there are now no dolphins on the Lao side.

We only draw a journey on the map when scientists have tracked it or clearly documented it. For this animal we have not found one yet.

Populations

The species is Endangered, and six small, isolated groups are Critically Endangered: the Mekong, Ayeyarwady and Mahakam rivers, Songkhla Lake, Malampaya Sound and Iloilo and Guimaras. News reports put the Mekong group in Cambodia at about 118 in April 2026, up from an estimated 89 in 2020. Chilika Lake in India counted about 159 in recent state counts. Bangladesh's coast and the Sundarbans hold the largest numbers.