Ever heard of the hoatzin? If not, that’s okay. It’s not exactly the kind of bird you can spot at every street corner. The hoatzin (Opisthocomus hoazin) lives in the Amazon. More precisely, it is mostly found along oxbow lakes.
An oxbow lake forms when a meander gets separated from a river, and thus becomes an independent lake. That happens a lot with the very snaky rivers crossing the low and flat lands of the rainforests.
Back to the hoatzin, that chicken-sized bird was among my top animal-spotting goals of my journey in the Peruvian Amazon. I just love this bird. It is not like just any other bird. When you spot it, you immediately notice that it’s special. When you know a bit more about its biology and its anatomy, it’s not just special but totally bizarre!
I gathered these facts to show you why this bird is such an oddity:
- 1. Its look
Ok, that’s not a very scientific statement, but just look at it. Have you seen anything like that before? A kind of “pheasant” with a long neck, red eyes, blue-skinned cheeks and an eccentric crest made of a bunch of feathers on its head!
- 2. It doesn’t fly much
Hoatzins are rather clumsy birds and they are bad at flying. They mostly hop from branch to branch around the oxbow lakes. This is because their pectoral muscles are not very developed, their digestive system taking more space than in other birds (see next fact).
- 3.It digests like a cow
Hoatzins are one of the very rare herbivorous bird species in the world. It just feeds on leaves of some trees that grow along the lakes. The leaves containing a low concentration of nutrients, it has to consume great quantities of it in order to get a sufficient amount of energy. Its large crop full of anaerobic bacteria help it digest the leaves by a process of fermentation. That makes this bird a ruminant just like the cow!
- 4.It stinks
The hoatzin is nicknamed “stinkbird”. The bad smell, result of its fermentation-based digestion, spreads in the whole of its body. It is never hunted by the local populations, because its flesh stinks and has a bad taste. It can, however, be hunted by hawks or other large birds.
- 5.It has clawed wings
The young hoatzins bear functional claws at the tip of their wings that help them move around the branches. This characteristic was shared by the 150 million year-old Archaeopteryx, the very first species of birds – an evolution of the dinosaurs. This has caused a long struggle for scientists to classify this bird! In the end, studies have shown that the hoatzin is not a living fossil and it was classified in its own order.
The young birds are the most vulnerable to predators, and the claws help climb the branches to escape these predators. If necessary, they would let themselves fall in the water and dive to escape the danger, and then climb back on the tree.The claws are lost at adult age.
Where did I go to spot hoatzins?
The Manu National Park is one of the most biodiverse region of the Amazon Basin. It can be reach by going on a tour to the park from Cusco. The itinerary will take you through the cloud forest down to the lowland rainforest, on the Alto Madre de Dios and Manu rivers. Along the Manu River, two oxbow lakes are usually visited: Cocha Otorongo and Cocha Salvador. Sailing is only permitted on the Cocha Salvador lake.
Zoom out on the map below to view (lack of high resolution imagery!).