Sotalia fluviatilis
Threat Index

Max Length:
Male: 1.50 m
Female: 1.50 m
Calf: 0.70 - 0.80 m

Max Weight:
Female: 53 kg

Est. Population: Unknown

Diet: fish, squid (marine populations)

IUCN Listing: DD
CMS Appendix: II
CITES Appendix: I
Tucuxi, Sotalia, Costero, Gray dolphin, Guianian river dolphin, Estuarine dolphin

Related Projects:
WDCS Supported projects in Brazil and Colombia

The tucuxi is known as the 'other dolphin' of the Amazon. This species has two distinct populations; and these are likely to be recognised soon as two distinct species: Sotalia fluviatilis being the river population and Sotalia guianensis the coastal marine. Reclassification is expected soon, until then ‘tucuxi' is now used when referring to the river population, and ‘costero' when coastal marine.

Individuals in the genus Sotalia are similar in overall appearance to the bottlenose dolphin although they are smaller, have a low triangular dorsal fin, broad flippers, and a narrow more pronounced beak. Colouration ranges from blue to grey with a lighter underside of white, grey, or pink. The freshwater individuals are generally smaller with individuals in the coastal populations up to 30% larger, although where their range overlaps it would be virtually impossible to distinguish between the two species.

Sotalia are usually found in small groups of only a few individuals although they can also be seen in groups of 20 or even 30 in coastal areas. They are extremely sociable and perform impressive acrobatics, including spyhopping, lobtailing, flipper slapping, and porpoising. They are, however, not known to bow-ride, are shy and difficult to approach although the the marine animals seem more inquisitive than their riverine relatives. They make short dives, usually lasting 30 seconds to one minute, and photo-identification studies in southern Brazil have shown some individuals to display long-term residency in one area.

Tucuxi are known to be distributed throughout the Amazon basin and possibly also in the Orinoco River. The coastal form (the ‘costero') are found in nearshore and coastal waters along the Atlantic coast of South and Central America, from southern Brazil in the south to Nicaragua in the north. There are also some reports of this species from some Caribbean islands. Threats to this species include direct kills – because of perceived competition and traditional medicine use, although interestingly they are also protected in many parts of their range because of myth and legend - pollution, accidental bycatch and entanglement in fishing gear, human disturbance and habitat degradation. Comprehensive population estimates are not available and the IUCN lists this species as Data Deficient (2008).