Amazon Sotalia
| Amazon Sotalia | ||||||||||||
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Skeleton of Sotalia fluviatilis in the Museum of Natural Sciences in Brussels. |
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| Sotalia fluviatilis | ||||||||||||
| ( Gervais & Deville , 1853) |
The Amazon Sotalia ( Sotalia fluviatilis , Syn . : Sotalia pallidus (Gervais, 1855), Sotalia tucuxi (Gray, 1856)) is a small species of dolphin that is called Tucuxi in its homeland . It lives in northern South America in the Amazon and its major tributaries such as the Rio Negro , Rio Madeira , Rio Tapajós , Río Putumayo , Rio Japurá , Río Napo , Cuyabeno , Río Ucayali , Río Marañón and Rio Tocantins . The Amazon Sotalia is not to be confused with the Amazon dolphin from the Amazon river dolphin family .
features
The Amazon Sotalia belongs to the family of dolphins (Delphinidae). It has a moderately elongated body and an average long, slender beak. It reaches an average body length of 1.40 meters and is one of the smallest whale species . The largest scientifically studied male was 1.49 meters long, the largest female 1.52 meters long. The forehead is clearly rounded by the melon , the beak well set off. The flippers are a maximum of 29 cm long, the fluke 42 cm wide. The fin is low and triangular, has a broad base, and the tip is sometimes curved in a hook shape. There are 28 to 35 teeth per half of the upper jaw.
The color of the Amazon Sotalia is gray on the back and white, light gray or a pinkish light gray on the belly. Flipper and Fluke are gray on the bottom. Behind the flippers there is a light gray zone, another one runs from the middle of the body to the anus . Some specimens show a light gray stripe that extends from the caudal fin base about 10 to 15 cm forwards and downwards.
From its closest relative, the Guyanese dolphin ( Sotalia guianensis ) , which occurs on the Caribbean and Atlantic coasts of Central and South America , the Amazon Sotalia differs genetically, through its smaller maximum length and four metric features with regard to the anatomy of the skull. It is not yet known whether both species are in contact with one another. The only possible place for both species to occur would be the mouth of the Amazon, since overcoming the rapids of the Casiquiare is considered impossible for it.
Way of life
The Amazon Sotalia lives in different social groups, including mother-child groups, families or larger groups of mostly 10, maximum 25 specimens. Because of the murky water of the habitat, echolocation is extremely important for orientation. His dives usually last 30 seconds, a maximum of 80 seconds. It feeds on fish and invertebrates. As scratch marks on the skin suggest, there are also larger, defensive fish such as various catfish . In contrast to other toothed whales , which usually swallow their prey immediately, the Amazon Sotalia seems to chew its food. The gestation period lasts about 10 months and the young are suckled for about half a year.
literature
- Caballero, S., Trujillo, F., Vianna, JA, Barrios-Garrido, H., Montiel, MG, Beltran-Pedreros, S., Marmontel, M., Santos, MC, Rossi-Santos, M., Santos, FR, Baker, CS: Taxonomic status of the genus Sotalia: species level ranking for “tucuxi” (Sotalia fluviatilis) and “costero” (Sotalia guianensis) dolphins. Marine Mammal Science 23, pp. 358-386, 2007
- Rüdiger Wandrey: The whales and seals of the world . Franckh-Kosmos Verlags GmbH, 1997, ISBN 3-440-07047-6
Web links
- Sotalia fluviatilis in the endangered Red List species the IUCN 2012. Posted by: Secchi, E., 2010. Accessed February 3, 2015.