Sotalia fluviatilis
Silhouette: Chris huh · PhyloPic
In 3 days ~60% in a week ~90%
The tucuxi (Sotalia fluviatilis), alternatively known in Peru bufeo gris or bufeo negro, is a species of freshwater dolphin found in the rivers of the Amazon basin. The word tucuxi is derived from the Tupi language word tuchuchi-ana, and has now been adopted as the species' common name. Despite being found in geographic locations similar to those of 'true' river dolphins such as the boto, the tucuxi is not closely related to them genetically. Instead, it is classed in the oceanic dolphin family, Delphinidae.
Physically, the species resembles the bottlenose dolphins, but differs sufficiently to be placed in a separate genus, Sotalia. The Guiana dolphin (Sotalia guianensis), a related dolphin present in coastal and estuarine environments and formerly grouped together with the tucuxi, have recently been recognized as a distinct species.
The tucuxi is frequently described (see references below) as looking similar to the bottlenose dolphin, but it is typically smaller at around 1.5 m (4 ft 11 in). The dolphin is colored light to bluish grey on its back and sides. The ventral region is much lighter, often pinkish. It is theorized that this pinkish color may be caused or... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Amacayacu National Natural Park | 🇨🇴 Colombia | |
| 2 | Anavilhanas National Park | 🇧🇷 Brazil |
Possible
About 20% of wildlife watchers report a Tucuxi sighting in Anavilhanas National Park on a given day, based on 6 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 3rd most-seen of the 5 mammals we can rate there. Over three days the chance rises to about 60%, and over a week to about 90%, if each day is a fresh chance.
June
In that month about 50% of wildlife watchers report a Tucuxi in Anavilhanas National Park on a given day, against under 5% in March–April, August, October and December–January, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Tucuxi sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Tucuxi sightings, Anavilhanas National Park ranks 2nd at about 20%. The best odds are in Amacayacu National Natural Park (Colombia, about 30%).
GBIF citizen-science records
It is estimated from how often the Tucuxi is recorded against all the mammals logged in Anavilhanas National Park (6 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
