Yellow-spotted Amazon River Turtle

The yellow-spotted Amazon river turtle is one of the largest South American river turtles, native to the Amazon and Orinoco basins and the river systems of the Guianas. It lives in tributaries and large lakes with calm water, and during the flood season may venture into flooded forests and floodplain lakes. Its diet mixes fruits, seeds, aquatic plants, fish and small invertebrates. Yellow spots on the sides of the head give the species its name and are most prominent in juveniles. As a side-necked turtle, it bends its neck sideways to tuck its head under the rim of the shell instead of pulling it straight back.

About the yellow-spotted Amazon river turtle

The yellow-spotted Amazon river turtle is a large freshwater turtle of northern South America's Amazon and Orinoco river systems. It is a side-necked turtle, folding its neck sideways under the shell rim instead of pulling its head straight back, and one of six living species in the South American river turtle genus Podocnemis.

Its scientific name is Podocnemis unifilis, and it goes by many local names. It is the taricaya or terecay in parts of its range, the tracajá in the Amazon region, the "peta de río" in Bolivia, and the "charapa" turtle in Ecuador and Peru. In English it is also called the yellow-headed sideneck turtle. It is one of the largest South American river turtles, second in its genus only to the Arrau turtle.

The name comes from the bright yellow spots scattered across the head. These are vivid in young turtles and fade as they age, so an old adult can look much plainer than a hatchling. The head narrows toward the nose, has a prominent groove between the closely set eyes, and is covered in large scales that give it a helmeted look. Like other members of its genus, it has a somewhat pig-like nose, though it is not closely related to the pig-nosed turtle.

The upper shell, or carapace, is oval and black, brown, or olive-green, and it darkens from grey to black as the turtle grows. Low keels run along the second and third scutes. The lower shell is greyish with darker patches. Strong legs with heavy claws and large scales end in webbed feet built for swimming.

Size differs sharply between the sexes. The species grows to about 45 cm (18 in) in shell length and up to 8 kg (18 lb), and females can be up to twice the size of males. Males have a longer, thicker tail, with the vent placed farther from the base than in females, which have a short, thin tail.

Behavior and diet

The side-neck is the key to understanding this turtle. Turtles in the suborder Pleurodira cannot pull their heads straight back into the shell. Instead they bend the neck sideways and tuck the head under the front rim.

The yellow-spotted river turtle eats a mix of plants and animals but strongly prefers plant food. Adults are mainly herbivores, feeding on fruit, seeds, weeds, aquatic plants, and algae. They also take fish, snails, insects, and other small invertebrates. Within a few days of hatching they start foraging alone on plant matter, grasses, fruit, leaves, carrion, and mollusks.

The river's flood cycle shapes its year. When the water rises in the flood season, the turtles move into flooded forest and floodplain lakes to feed. When water levels fall, the females come ashore to nest.

Nesting is timed to the peak of the dry season, so the eggs hatch before the rainy-season floods can wash the nest away. Females dig nests in sandy areas on riverbanks and usually lay two clutches a year, each with 4 to 35 eggs. The eggs hatch 66 to 159 days after laying, depending on conditions.

Temperature decides the sex of the young. Eggs incubated below 32 °C (90 °F) hatch as males, while those kept above 32 °C hatch as females. Turtles become able to breed once they reach about 30 cm (12 in) in shell length.

Many animals prey on the species, including birds, snakes, large fish, frogs, mammals, and people.

Range and habitat

The yellow-spotted Amazon river turtle is native to the Amazon and Orinoco basins and the river systems of the Guianas. Countries in its range include Brazil, Peru, Venezuela, Colombia, Bolivia, and Ecuador. It is common in many of these areas.

It favors calm, slow water: tributaries, large lakes, lagoons, and the edges of rivers. During high water it spreads into flooded forest. Sandy areas on riverbanks matter too, since that is where females dig their nests.

Yellow-spotted river turtle vs Arrau turtle

The yellow-spotted river turtle is often confused with its larger relative, the Arrau turtle (Podocnemis expansa), and with the six-tubercled Amazon River turtle. The clearest differences are the facial spots and adult size.

The Arrau turtle is the largest of all side-necked turtles and nests in big groups on river beaches.

Conservation status

The yellow-spotted Amazon river turtle is listed as Vulnerable on the IUCN Red List. That assessment dates from 1996. The species is also on CITES Appendix II, which controls international trade.

The main threat is people. Its meat is widely eaten where it lives and is a target of illegal hunting, and its eggs are also collected and eaten by riverside communities. Nesting females are especially easy to catch, because they move slowly on land. Turtles are also taken in gill nets.

The species was one of the foreign turtles caught up in the American pet turtle trade of the 1960s. Imports into the United States are now strictly regulated by federal law, but a captive, self-sustaining population exists in the country, some of it in public animal collections and some with private keepers.