Inia geoffrensis
This species is found in the Orinoco and Amazon basins, South
America.
The Guarayo Indians of Bolivia call this dolphin Inia. When
Geoffroy St. Hilaire found the type specimen, he used the
Indians' name for the genus. Its common name, Boto, is often
incorrectly spelt as either Bouto or Boutu.
Local Names: Amazon River Dolphin; Boto Vermelho; Bufeo;
Tonina; Pink Dolphin; Pink Porpoise.
The Boto is the largest river dolphin; it has a very large
melon and slender, slightly curved beak with bulging cheeks.
The flippers are large and curve to a point with a ragged
trailing edge. The body is plump yet tapers to the tail, and
a humped dorsal ridge exists instead of an actual fin. The
body colour is blue-grey, vivid pink or off-white. Adults
reach 2.6m in length, and weigh around 160kg.
The Boto, with its humped back and long beak, cannot really
be mistaken for other cetaceans that inhabit its waterways.
Botos are mainly found in brown, slow-moving waters. These
dolphins readily leave the main river channels in December-June,
the flood season, and enter flooded grasslands and forests.
During the dry season, some individuals can become trapped
in stagnant ponds - and, since fish are also trapped, the
dolphins usually survive well.
Boto feed upon a variety of fish and crabs, mostly bottom-dwelling
species but also some schooling. Small turtles are also occasionally
taken.
This species is not often seen in groups larger than 2, but
in rare circumstances up to 15 may be seen together. They
are slow-moving animals that are able to move their head in
any direction, which is due to the unfused vertebrae in the
neck. Though their eyes are small they can see quite well,
except for their bulging cheeks hampering downward view. This,
however, is overcome by swimming upside down.
Approximately 30 years.
Unknown.
Due to the escalating devlopment in the Amazon basin, the
Boto faces much exploitation. Small irrigation projects cause
the drying up of small lakes and ponds, whilst the larger
hydroelectric projects disturb both the Boto and its prey,
creating small isolated populations in areas of little food.
Fishermen see them as competition for fish, and so kill them.
Some are taken also so that their eyes and sexual organs can
be sold as love charms; others are taken live for aquarium
collectors. In 1988 this species was given full protection
in Brazil and Bolivia, and is partially protected in areas
of Peru, Venezuela and Colombia.
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