In the top ten living oddities of the Amazonian jungle, the Hoatzin (Opisthocomus hoazin) would easily occupy one of the first three positions. Found commonly in Peru, Bolivia, Colombia, Venezuela, Ecuador, Suriname, French Guiana and Guyana (who went one step further and adopted it as its national bird), the Hoatzin lives in mangroves, swamps or riparian forests.
While undoubtedly exotic, the appearance of the Hoatzin ( pronounced Hoh-at-sin or Waht-sin) is not extraordinarily uncommon. The general body plan is similar to that of a pheasant, hence one of its common names, the Canje pheasant. Measuring roughly 65 centimeters in length and weighing around 1 kilogram, the hoatzin is mostly made up of feathers displaying a reasonably spectacular array of colours from an intense brownish-yellow chest, to maroon and black wing feathers and tail, with some white streaks through the coverts (feathers on the upper part of the wing). The head is relatively small bearing a loose crest, and a straight beak. And that’s not all, it’s devilish red eyes are surrounded by an unusually bright blue and featherless patches. Some go as far as calling it ugly, a bit harsh to describe a mere lack of grace in this creature’s movement – a direct result of the internal workings of this animal, which is what truly earned it the place amongst the South-American oddities.
The hoatzin is a folivore, meaning its diet is largely composed of leaves from about 50 different tree species, with the occasional flower or fruit. The problem with this source of food is that it is very low in nutrients, as well as containing the undigestible cellulose. So not only has the hoatzin got to eat A LOT of leaves, but it also has to find a way to pass them through its system. And so, this strange creature, possesses a digestive tract more similar to a cow’s than to a bird’s.
Following the chewing of leaves with its crenulated bill (again, unique among birds), they undergo a bacterial fermentation process in the large crop – folded in two compartments, which does not leave too much room for the stomach and gizzard, leaving the former two greately reduced. A by-product of this kind of digestion, as you might have guessed, is an unpleasant cow’s manure-like smell, earning the hoatzin another well deserved common name, the stinkbird.
The stomach and gizzard are not the only organs that had to be sacrificed to make room for the large foregut. The sternum keel is also reduced and thus with it, the flight muscles. This explains the lack of grace mentioned earlier: hoatzins are not at all, skilled fliers. While so many other birds’ flight is delightful to watch, the hoatzin does little more than stumble clumsily from branch to branch, crash-landing more often than not.
The hoatzins lay between one and five eggs, incubated for a month long. Its young are fed a leaf paste, regurgitated either by the parent or older sibling. The chicks are even greater wonders of nature than the adults. They hatch with a pair of claws on each wing which they retain until three months of age. This is a unique feature and endless source of puzzlement in the scientific community trying to classify the already controversial bird. The claws are a useful tool that helps chicks cling to the safety of the nest. However, if a predator approaches too close for comfort, the chicks take a leap of faith and jump straight out of the nest, which is always built above water, and swim to a safe location. Although rather scrawny looking, they are very strong swimmers. When the danger has passed, they climb back into the nest, using their ever so helpful claws.
Hoatzins are famous for their foul tasting meat, so fortunately for them, they’re only hunted in desperate times. Also, apart from raptors preying upon chicks, they have no real natural enemy. If you ever hope to observe a live hoatzin, the best thing to do is to travel to South America, as they don’t survive in captivity. Luckily, they’re common, highly social and produce all sorts of vocalizations, such as croaks, hisses, grunts, groans and squawks, so there’s little chance you’ll miss them. However, be respectful of their space, it has been proven that uncontrolled tourism is the second largest (after deforestation) threat to this wonderful creature.