An Amazon River Dolphin (Inia geoffrensis) eating an armored catfish
Among the rarest and most endangered of mammals are the beautiful river dolphins, a group of magnificent freshwater cetaceans which live in certain huge river basins in Asia and South America. Up until today, science knew about the Ganges River Dolphin (Platanista gangetica), the Amazon River Dolphin (Inia geoffrensis), the Bolivian river dolphin (Inia boliviensis), the Yangtze Dolphin (Lipotes vexillifer), and the La Plata River Dolphin (Pontoporia blainvillei). I have a weakness for river dolphins and each of these incredible species is worthy of a much longer post! In fact my ill-fated toy company, River Dolphin Toys, was named for the botu, the playful pink river dolphin of the Amazon River (but, alas, making good toys is no substitute for being well-organized, ruthless, and severe). China’s Yangtze River Dolphin was one of the prettiest animals alive but it is now functionally extinct (the tale behind the mass death of these beautiful white dolphins is a profoundly sad story of modern China which I will tell some other day when we all feel stronger). The Ganges dolphin is swiftly going extinct because of…actually, let’s cover the known river dolphins some other time. Today’s news is about the new river dolphin species which was just discovered: the Araguaian river dolphin, Inia araguaiaensis!
The Araguaian river dolphin (Inia araguaiaensis) eating a fish. Can you spot the differences? (photo by Nicole Dutra)
The Araguaian dolphin lives in the Araguaia River (a tributary of the Tocantins River) in a rainforest watershed habitat very much like the Amazon. Araguaian dolphins look nearly identical to Amazon dolphins and were long regarded as a subspecies. Both river dolphins are clever alpha predators of the river with sharp wits and long toothy rostrums for catching tasty freshwater fish. As it turns out however, the two species diverged 2 million years ago when the rivers became separate. Despite a similar appearance to the Amazon River dolphin, the Araguaian dolphin has a larger brain case and different genetic makeup. Araguaian dolphins do not interbreed with either of the other two known Inia dolphin species (although I have no idea how scientists discovered this fact). The “new” dolphins are threatened by deforestation, fishing, and hydroelectric dams. Indeed, biologists speculate that only a thousand individuals are left in their population. Hopefully the Brazilian people will find a way to protect the lovely and intelligent animals before they too vanish forever.
ferrebeekeeper 
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January 24, 2014 at 5:38 AM
thieblemontclement
Thank you for this!
January 26, 2014 at 10:20 AM
Beatrix
Amazing, overlooked news from several months ago out of India-
India’s Ministry of Environment and Forests has decided to forbid the keeping of captive dolphins for public entertainment anywhere in the country.
In a policy statement released Friday, the ministry advised state governments to reject any proposal to establish a dolphinarium “by any person / persons, organizations, government agencies, private or public enterprises that involves import, capture of cetacean species to establish for commercial entertainment, private or public exhibition and interaction purposes whatsoever.”
Why?
“Whereas cetaceans in general are highly intelligent and sensitive, and various scientists who have researched dolphin behavior have suggested that the unusually high intelligence; as compared to other animals means that dolphins should be seen as ‘non-human persons’ and as such should have their own specific rights and is morally unacceptable to keep them captive for entertainment purpose,” the ministry said.
Way to go India!!!!