Stinky Birds and Howling Monkeys

OK, all you armchair travellers out there - lace up your sturdy boots, tuck your trousers into your socks (who knows what might nip up your trouser leg while you are not looking) and douse yourselves with DEET - we are off to the jungle.............

At the end of my last post, I was looking forward to descending from the high altitude cloud forest into the lowland rainforest of the Peruvian Amazon. I was anticipating well-oxygenated muscles and some heat for my cold weary bones. Imagine my indignation when, three hours into our boat trip up the Manu River I discovered that I was freezing to death. I could not believe it – I was going to die of hypothermia in the supposedly hot and sweaty jungle! There I was, in my down jacket, enshrouded in my enormous poncho that has enough space under it for all the passengers in the boat, wishing that I had put my thermal underwear on that morning. The wind was whipping in our faces and spray from the river was cascading over the side of the boat, raining down on our huddled forms. I was not happy. The caimans, perched menacingly on the banks of the river, seemed to be enjoying my discomfort, grinning from “ear to ear”.

Still, as with all good things, all bad things also come to an end and, after six bone-chilling hours, we arrived at Manu Park Lodge, in the heart of the Manu Biosphere Reserve. I rushed into the Lodge and straight into a lovely hot shower .......... oh no, wait, there were no hot showers – it is the hot, sweaty jungle - people want cold showers here, right? Oh well, at least I could don my trusty thermals and another layer of fleece. I was tempted to snuggle down into my down sleeping bag, but there was a rainforest out there just waiting to be discovered...........


So off we trot on our first walk in the forest. Our guide takes a lot of time explaining to us that we might not actually see anything. He understands that we all want to see the jaguars and the giant otters, the tapirs and the peccaries, the huge snakes that can swallow a cow whole, but, well, there are a lot of trees in the way and the vegetation is quite dense and the animals are very shy and most only come out at night so really, we should be happy if we get to see a couple of ants and perhaps a spider or two. The funny thing is, while I would give my eye teeth to see a jaguar and I really did come all that way to catch a glimpse of a giant otter, I actually was quite excited to see a couple of ants. But then, these were no ordinary ants – these were huge bullet ants. One-inch long, jaws that look strong enough to bite your finger off and a nickname of the 24-hour ant, so called because if one does bite you, you will be in pain for the next 24 hours. Our guide certainly earned his tip when he held up one ant on a stick for 10 minutes while I tried to get some good photos of it not biting his finger.

I was also happy just to be surrounded by all the life of the rainforest. The many species of trees, all reaching up to the sunlight, draped with lianas, with ferns and bromeliads using their branches as perches high up in the canopy, competing for their own little patch of sunlight. Down on the forest floor in the carpet of leaves, colourful grasshoppers leap off in all directions as your foot descends on their little patch of undergrowth. Ants march in orderly lines, always apparently knowing exactly where they are going and what their role is within their regimented colony. Flashes of colour flirt with your peripheral vision – was it a bird, a butterfly, a falling petal from a flowering tree? Fungi sprout from fallen trees, delicate white caps on long slender stalks, orange and brown shelves jutting from the sides of dead, but certainly not lifeless, trees. The long, cylindrical body of a millipede goes trundling by on the undulating waves of its many legs. A spider gets to work repairing the trap that you have just destroyed as you wander along through this web of life. You may not be able to see the jaguar stalking past or the harpy eagle snatching a monkey from a nearby tree, but you know that they are all out there, you can feel the living forest breathing, moving, constantly changing around you.

Having said all that, I really did want to see something big and furry........

You know that when your guide suddenly stops and starts staring intently into the forest, his hand held up, motioning for silence, that there is something out there. In most cases, you do not have a clue what he might have seen or heard. No matter how hard you look or how much you strain your ears, as far as you can tell, there is nothing there. However, there are times when even I could tell something was afoot in the jungle. You would hear branches snapping, see the canopy moving, and large objects would start falling from the canopy onto the forest floor below – were they falling, or were they being thrown? The sound and the movement would travel towards you and then, suddenly, the forest would come alive around you. Monkeys! Large family groups of squirrel monkeys and capuchin monkeys, moving through the forest, from one tree to the next, not worrying about being quiet or staying hidden from view. Acrobatic leaps from one branch to another - Cirque du Soleil eat your heart out! Every so often, one would stop and stare down at you, bare its teeth and then throw something in your general direction. I am pretty sure it was just bits of branches, but I was always a little wary of being in the line of fire of gobs of monkey poo. We might love to watch these furry little fellows, but they were not so keen on being watched or having their territory invaded by us.

Early the next morning, I was woken by, well, I was not really sure at the time. To begin with, I heard what sounded like a gentle breeze rustling through the leaves of the trees. This breeze increased in strength to a wind blowing through the branches, up to a gale howling down the valley, screeching around the building, tearing through the branches. It was as if a freight train was barrelling towards me or a wall of water was thundering down upon me. I was starting to worry, when the maelstrom of sound began to coalesce into distinct hoots and bellows and, as the sun dawn, it dawned on me what was making the noise – howler monkeys. Every morning and every evening, as sure as the sun rises and sets, the male howler monkeys ensure that every living creature in the jungle knows where they are and what part of the jungle is their home. The males actually have specialised throat chambers, made from an expansion of skeleton that they use to produce these amplified sounds. For me, the howlers made a very convenient alarm clock, and I knew that it was time to get up and head back out into the jungle.

I love the jungle in the early morning. It is still cool and that layer of sweat, which will inevitably cover you as the heat builds, has yet to form. As the sun rises, the mist that hangs over the lake slowly burns off and the sun lights up the surrounding forest. Many of the animals of the forest also appreciate the cooler temperatures and it is a great time to be out and about looking for those elusive giant otters and jaguars. OK, so, maybe you won’t see them, but you will certainly see many birds and other animals. One morning, we took to the canoe and went gliding silently over the still waters of the lake, searching the forest edge for signs of life.


The stillness was abruptly and rudely broken by a group of stinky birds. Now, I got to know the stinky bird quite well while in the jungle. It was quite difficult not to, the amount of noise and commotion that they make wherever they go. To me, the stinky bird was quite fascinating, just because it seemed quite the opposite of almost all the other animals in the forest. It was loud, noisy and obnoxious and it appeared to be quite useless at everything. It stumbled around in the branches, crashing from one bush to the next, only capable of flying for around 20 seconds at a time. Unlike other animals of the jungle, it was never hard to find a stinky bird. If you couldn’t hear one screeching, squawking, growling like a cat (I actually thought that I had two jaguars fighting behind my room one night, but it turns out that it was two stinky birds growling at each other), you could see them crashing into some bush or tree on the side of the lake or you could smell them from quite a distance – stinky by name, stinky by nature. Now obviously they were doing something right, since I saw more stinky birds than any other animal in the forest. The question is, what? I needed to do a bit of research about this intriguing creature.


As a biologist, I will often look at an organism and marvel at how well adapted it is to its environment. An eagle with its superb eyesight, razor sharp talons and a ferocious beak that can rip into the flesh of its poor hapless prey. A penguin, that on land may appear comical and useless, but underwater becomes a graceful torpedo, slicing through the water with ease and grace. Think of a hummingbird, with its incredibly light skeleton and wings that can beat faster than any other bird, allowing it to hover and manuever with skill and precision. Now, lets look at the stinky bird. It certainly breaks no record as a flyer, only managing 20 seconds at a time. It is not graceful, it is not fast. It is no good at being quiet and it certainly does not use camouflage to blend into its background to become invisible, like a nightjar on its nest. It is not a ferocious predator, nor does it have any ability to stalk or ambush prey. So, just how does it survive? What does it eat and why isn’t every carnivore in the forest chowing down on this very visible but not very mobile bird?

Well, let’s just look at some of the adaptations that make the stinky bird, more properly known as the hoatzin (Ophisthocomus hoazin), so special. For food, they make use of fruits and leaves that many other animals find hard to digest. They are able to do this because they have an enlarged crop that acts as a fermentation chamber, in a similar manner to the rumen of a cow. This system is unique among birds and leads to unpleasant odours emanating from the bird, hence the local name. Another side effect of the enlarged crop is the lack of room for flight muscles, hence the lack of any grace or endurance in flying. So, the stinky bird does not need a whole lot of skill to find its food. Instead, it is fabulously adapted to use food that other birds cannot. So, that answers one question. But what protects this unique bird from its potential predators? It turns out that the stinky bird not only stinks, but it also tastes foul! So, you can catch it, but would you want to eat it?

Before I leave the stinky bird, I have to mention another bizarre and unique characteristic of this most unusual bird. The chicks have two claws on each wing. This allows them to cling onto the branches around the nest and allows them to climb back into it if they are daft enough to fall out of it and into the water below. Is this a link to their reptilian past? Many biologists have tried to work out the history of this bird and how it is related to other bird groups, but all to no avail. Even with DNA sequence data, the taxonomic position of this bird remains obscure and greatly debated, so much so that it remains in a family and suborder all by its stinky little self.

While the hoatzin is a very conspicous inhabitant of the jungle, many other animals are much smaller, quieter and harder to spot, particularly those that only come out at night. To see these, you have to venture out into the forest at night, armed with a flashlight and a large container of insect repellent. I figured if the predators wouldn’t eat the stinky birds due to their foul taste, they certainly wouldn’t eat anything doused in 95% DEET! Secure in the knowledge that no jaguar with functioning tastebuds would take a chunk out of me (just because you never see them, doesn’t mean that they are not out there........), off I went in search of the small. Being an entomologist, obviously I was drawn to the insects that I saw. Many belonged to the grasshopeer and cricket family and most of them were very good at looking like something else. As you can see with this brown katydid that is disguised as a leaf that has already been half eaten. This might put off insectivorous predators, but I would be a bit concerned that some herbivore might sneak up behind me and try to take another bite out of my leafy behind!

Take an insect and add an extra couple of legs and you end up with my favourite group of creepy crawlies that send shivers down my spine, the arachnids. Now I think that I have made it abundantly clear that spiders do not make me all warm and fuzzy inside, and yet I cannot help but find some beauty in their form and function. This does necessitate me getting close enough and staying close enough, long enough, to actually get a good look at them. The photo of this little charmer was taken using a macro lens, not a zoom lens, so you can appreciate how close I had to get to her. The things I do for science!

Along with spiders, there are other much cuter creatures that are out and about at night looking for a tasty six-legged snack. One of my all time favourite animals and one that I have spent many an hour looking for in the bug-infested jungle when really I should be tucked up safe and sound in my mosquito netted bed, is the tree frog. Of course, there are many species of tree frog out there, but I am not fussy about which I see, since they are all just so endearing, with their bug-eyes – all the better for seeing you with in the dark, their wide mouths – all the better for eating you with, and their splayed toes with flattened pads on the end, all the better for clinging to the leaves and vegetation of the jungle with. Of course, the question arises – why spend time looking for them in the jungle when the reality is that there is nearly always at least one living in the toilet or the shower? I don’t know, but it is somehow just not the same seeing them in the bathroom.


So there you have it, a glimpse of just some of the myriad of life that can be found in the Peruvian jungle. I never did get to see the giant otters, but that just gives me something to look forward to on my next trip into the jungle. I am bound to see them then, aren’t I? I shall finish with a little biological brainteaser for you. Here are just two of the gorgeous lepidopterans that I saw and actually managed to capture on film. Now, most people think of butterflies as being the belles of the ball and moths as the drab, ugly ducklings. Given that, which one of these is the moth and which the butterfly? I think that we can all agree that whichever the moth is, it is no ugly duckling.