Tucuxi; Bouto Dolphin

The Tucuxi Dolphin resembles a small Bottlenose Dolphin. Both the Tucuxi and Bottlenose Dolphins are a light gray to buluish-grey in color on their backs, with a pinkish to light gray on the belly areas. The beaks of the Tucuxi is slender and long, similar to the Bottlenose Dolphins.

The Tucuxi has two sub-species, the Sotalia Fluviatilis Fluvratilis which is the freshwater species, and the Sotalia Fluviatilis Guianensis is the marine species.

The Marine Tucuxi reaches 2.1 to 2.2m in length, while the Riverine Tucuxi only reaches 1.5m in length. Both the Marine and Riverine Tucuxi have slightly different social behaviors. The Marine Tucuxis are found traveling in groups as high as 30 dolphins. They are usually seen traveling in the Bai de Guanabara and Cananeia. The juvenile Marine Tucuxi travel in small groups, typically consisting of 2-3 adults and one calf. The Riverine Tucuxis Dolphins are found with only 1-4 in a group swimming together. Little is known about this species of dolphin but they are found in the Amazon River. More research is being done now to help us better understand their habits.

Both the Riverine Tucuxis and the Marine Tucuxis Dolphins are found in fresh and salt waters. They can be found in waters around Florianopolis Brazil, the Caribbean Sea, Northeastern Nicaragua, Layasiksa River, and the Amazon River. The population size of the Riverine and the Marine Tucuxis is unknown. They do both seem to be well populated.

In the few studies that have been conducted to help in better understanding both sub-species of the Tucuxis Dolphins, it has been noted that they prefer shallow protected waters, such as estuarines and bays.

The migration of both Tucuxis sub-species vary upon the water levels where they live. When water levels are high they are found migrating to lakes and small channels. When waters receed these dolphins are found migrating back to rivers and larger bodies of water to protect themselves from becoming beached. It has also been noted that they don't always migrate at all, they will stay in one are for an entire year.

Threats to both the Marine and Riverine Tucuxis dolphins are incidentally caught in fishermans nets. Also the increase of damms being built in the rivers decreases the migration of the dolphins. These damms also pose a threat to fish migration which causes changes in the primary fish that both the Marine and Riverine Tucuxis Dolphins eat.