Amazon river dolphin

How it lives

The largest river dolphin. Males are bigger and pinker than females. It lives alone or in small groups of about three or four, is mostly active around dawn and dusk, and finds its way in muddy water by echolocation. Births are concentrated in May and June after a pregnancy of about eleven months. Lifespan in the wild is not documented; some captive animals lived 10 to 30 years, and one lived over 46.

Where it goes

It moves with the river. It uses main channels, tributaries, lakes and, in the high-water season, the flooded forest, and it shows strong attachment to particular areas.

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

Endangered (IUCN, assessed 2018), with a declining population. In the Mamirauá Reserve in Brazil, counts fell by about 6.7 percent a year, roughly halving every ten years since 2000 (surveys 1994 to 2017). A later modelling study estimated a decline of about 5.5 percent a year and a 95 percent loss in 50 years if nothing changes. Population estimates elsewhere vary widely. The main threats are deliberate killing for fishing bait, entanglement in nets, mercury pollution and dams. In September 2023, high water temperatures in Lake Tefe were linked to the deaths of 154 dolphins. Three subspecies are recognised. It is listed on CITES and CMS Appendix II.