Also known as: Hoactzin, Stinkbird, Canje Peasant, Flying Cow, Shansho (locally)
Average length: 61 – 66 cm (24 – 26 in.)
Adult weight: Up to 816 g (28.8 oz.)
Diet: Primarily leaves, supplemented by flowers and fruits.
Natural predators: Birds such as hawks, toucans and falcons, and snakes, e.g. anacondas
Life span in the wild: up to 15 years
Clutch size: 2 – 5 eggs
Natural habitat: Swamps and riverside forests.
Geographical range: throughout the Amazon rainforest and Orinoco delta, from Venezuela to Bolivia and from Ecuador to Brazil.
Interesting Hoatzin facts
This prehistoric-looking bird has no close relatives and is often said to show the evolutionary transition from reptiles to birds. Because of its uniqueness, scientists gave the Hoatzin its own species family.
Until they are adults, Hoatzins have two claws on each wing – babies use them to help them clamber up vegetation. Because of this trait, they have often been linked to the first known prehistoric bird Archaeopteryx from the dinosaur era, though this has never been proved.
It is one of the only herbivorous birds in the world and is the only known one to have a digestive system that functions using bacterial fermentation, like cattle.
They are often called “Stink Birds” because of the unpleasant odour given off by their digestion processes.
When young Hoatzins feel threatened in their nests they often plunge into water (often diving over 10 metres), swim to shore and then clamber up the vegetation with their wing-claws. Adult Hoatzins cannot swim.
They are very clumsy flyers due to the oversized gut they have for digesting their food, which does not leave space for a stronger breast bone or flight muscles.
Like cows, Hoatzins take hours to digest their food and spend most of their day sitting on branches, digesting.
They are highly social birds and form family groups of up to a dozen individuals. Flocks of 40 or more birds are said to have been recorded.
The Hoatzin is the national bird of Guyana (a small country in north-eastern South America). Its national animal is the Jaguar.
IUCN conservation assessment
Estimated world population: Unquantified but believed to be less than 10,000 mature individuals.