Researchers in Brazil have identified a new species of river dolphin living in the Amazon’s Araguaia River Basin.
Named after the river it was found in, the Araguaia boto river dolphin species diverged from their closest relatives around two million years ago, when the Araguaia-Tocantins Basin separated from the Amazon Basin. This amazing mammal is smaller than other species, with a wider skull and a different number of teeth.
It is one of only a few existing species of river dolphin in the world, and the first to be discovered since 1918.
Scientists have estimated there are only around 1,000 Araguaia boto river dolphins in existence, a relatively small number which raises concerns about the future of this species.
The plight of the river dolphin is very real, as demonstrated in 2006 when a rare Chinese river dolphin called the baiji—nicknamed “the goddess of the Yangtze—was declared extinct.
The Amazon’s Araguaia boto river dolphins have been found to have extremely low levels of genetic diversity, which could jeopardize reproductive success. They are also threatened by a variety of human activities including agricultural and ranching activities, hydroelectric projects, increasing boat traffic, logging, mining, and pollution.
Fortunately, some countries have taken measures to enact laws protecting river dolphins from pollutants. In 2012, Bolivia introduced new legislation banning fishing of freshwater pink dolphins, acknowledging this act was only the first step towards conservation, since the main threat to the species is mercury contamination of rivers by illicit and unregulated gold mining operations.
As we learn more about this new species and the anthropogenic activities that threaten them, it is hoped that policymakers in Brazil will takes steps to protect the river dolphin, a national treasure.