Hoatzin

• GeneralIt digests leaves by fermentation as a cow does, which gives it a strong smell of dung.
• anatomíaIts chicks keep working claws on their wings, used to climb about the branches before they can fly, a trait that recalls some prehistoric birds.
• It is the only bird in the world that ferments leaves in its crop, like a ruminant: that crop takes up so much room that it has displaced the flight muscles, which is why it can barely fly more than a few metres.
• Its smell of manure, the result of that fermentation, has earned it the nickname of stinkbird and has probably saved it from hunting throughout Amazonia.
• The chicks have two working claws on their wings: if a predator approaches they drop from the nest into the water, swim, and then climb back up the tree using those claws, which they lose as they mature.

Skeleton type

Vertebrate - internal bony skeleton (bird)

Habitat and environment

Riverside vegetation along rivers, lagoons and flooded forest of the Amazon and the Orinoco

Birth weight

Altricial: born blind, naked or with sparse down and entirely dependent

Size at birth

Born with functional claws on its wings, which it uses to climb back if it falls into the water

Sexual maturity

2 years

Gestation / incubation

31 days of incubation

Litter / clutch size

3 eggs

Sources consulted: Wikipedia (es): Opisthocomus hoazin

Best time: All year round along the banks of rivers and lagoons in Amazonia and the Orinoco, by day; it is a clumsy flier and shows itself readily.