Rendezvous with bats

Malaysia | Anno 2016

 

Monday, March 28 | Kampung Long Iman

Tuesday, March 29 | Gunung Mulu National Park

Wednesday, March 30 | Gunung Mulu National Park

 

 

Monday, March 28 | Kampung Long Iman

Pale sandy tracks draw long, parallel lines through the lush greenery. The Malaysian rainforest had to give way here to the geometric pattern of palm oil plantations. Further on, the mud-brown Baram River winds sensuously through the flat land in a hundred and one bends.

It almost feels like we're flying over a giant broccoli plantation

Then the untouched rainforest of Brunei appears. It looks as if we're flying over a massive broccoli field. Ecological conservation is still held in high regard here. Palm oil plantations don’t stand a chance. They don’t need to either, as Brunei generates ample income from its vast reserves of crude oil and gas. To the right, the 2 376-meter-high Gunung Mulu rises proudly above the wilderness.

Suddenly, in the midst of this green abundance, the tiny village of Mulu appears. The village owes its existence solely to the proximity of the national park of the same name. You can only reach it by a difficult journey along the rivers or by air – two flights a day from Miri. It's half-past two when we land on the modest airstrip.

Petrus is waiting for us and guides us to our mode of transport – a spartan cross between a bus and a tram, with wooden benches and open windows. A sign warns us, somewhat redundantly, that if it rains, we’ll get wet.

 

Mulu National Park – Melinau River

Exactly 2 588 meters separate us from the hotel, if we are to believe the signpost. On flawless asphalt, no less. How they managed to lay such roads – few as they may be – in the middle of the jungle is anyone's guess.

 

Melinau, Gunung Mulu (in the distance)

Hotel

A little later, we cross the Melinau via a narrow Bailey bridge and suddenly find ourselves on the hotel grounds. In the middle of the rainforest, in a sharp bend of the river, they have built the hotel here. We are greeted by a chorus of thousands of singing cicadas, accompanied by countless other indescribable jungle sounds. Wide walkways lead us to wooden chalets on high concrete stilts. We are surrounded by overwhelming nature. Everything here is in XXXL size – even the moths.

 

Cicada		Moth
Beetles		Cicada cocoon

However, the Berewan – the tribe to which Petrus also belongs – were initially not at all pleased with the development of such hotel infrastructure and everything that came with it. It was only when they were actually offered jobs that they came around.

Here, you get around via the rivers. The preferred mode of transport is the prao panjang, the motorized longboat with a shallow draft that can hold four to six passengers. Adorned with orange-red life jackets, we set out in four longboats, as we are on our way to find the Penan, the last nomadic tribe of Borneo.

 

Melinau

Swiftly, we follow the Melinau downstream. Towering above us on both sides of the river is a green wall of vegetation. It must be teeming with birds, given the amount of noise, but for now, not a single living creature is visible.

A little over two kilometres further, the crystal-clear Melinau flows into the chocolate-milk-brown Tutoh. Apparently, there's been significant erosion upstream – likely due to logging for plantation development – causing the river to carry so much soil with it.

 

Tutoh River

Upstream, we now follow the fast-flowing Tutoh. It has been very dry here lately, with only a bit of rain falling the day before yesterday. As a result, the water is a bit rougher. Another three kilometres ahead, Kampung Long Iman, a village of the Penan, appears on the left bank. Children are playing noisily in the water along the shore, enthusiastically waving to our boats with a warm welcome.

 

Kampung Long Iman

A Penan village? That’s a contradiction in terms. The Penan are still hunter-gatherers – nomads through and through, who never settle anywhere. A Penan has as much business in a village as an Argentine in a vegetarian restaurant.

But nomads wandering unchecked through the rainforest – beyond anyone's control – doesn’t sit well with the Malaysian government. So, they've built a longhouse by the river, where the Penan are forced to settle, whether they like it or not. The Penan, however, aren’t too keen on this idea, but apparently, they have no means to resist it.

A Penan village? That’s a contradiction in terms

Inner courtyard with papaya tree

One of the first Westerners to come into contact with the Penan was Bruno Manser, a Swiss shepherd in search of a lifestyle closer to nature. He was so enthusiastic about his experience that he chose to live among the Penan, adopting their way of life.

As early as the 1980s, Manser understood the threat that unchecked logging posed to biodiversity and to the nomadic lifestyle of the Penan. He successfully sabotaged the logging industry’s operations, for example by driving 25 cm steel nails into trees, which would then ruin the chainsaws – though this also posed great danger to the loggers themselves.

The Malaysian government was not amused and declared Manser persona non grata. He continued his activism in the West, using daring stunts to draw increasing attention to the dangers of deforestation. In 2000, during yet another attempt to illegally enter Sarawak from Kalimantan, he disappeared without a trace. His body was never found.

 

Kampung Long Iman – Longhouse

In Kampung Long Iman, it is quite peaceful as we disembark. Most of the residents are working elsewhere. Elders, women, and children have the village to themselves. With its concrete foundation, brick walls on the ground floor, and wooden walls on the first floor, this industrial version of the traditional longhouse hardly impresses us. Sunlight has little chance to penetrate the dark rooms. Surrounding the longhouse are a few separate houses, some of which are rather dilapidated.

 

Penan women play a flute with their nose…

… or a string instrument with their teeth

The broad, long veranda has almost the feel of a covered street. People sit on benches. Apathy seems to prevail. Only the children shake off the gloom, running around joyfully and observing the strange visitors with wide eyes.

Much to our surprise we learn that nose flutes actually exist. A Penan woman demonstrates its use for us. In essence, the instrument is not very different from a recorder. Only the sounds produced are somewhat weaker, and you should hold the mouthpiece in front of the nostrils, and not in front of the mouth.

 

 

Even more delicate is the tiny string instrument another woman plucks with her teeth, using her mouth cavity as a sound box. A bamboo stick also apparently produces harmonious sounds when you stretch a few strings over it. However, you definitely won’t receive complaints about noise pollution with such instruments.

 

Weaving a cylindrical bag

Further along, a young woman is weaving a beautifully decorated, cylindrical bag from reeds with white and black strips. They also make pendants from the seeds of the sea bean, known for their exceptional hardness.

It’s not easy to work with the hard ironwood from which blowpipes are made

But it's the blowpipes that fascinate us the most. It’s not easy to work with the hard ironwood from which they are made. You start by soaking a perfectly straight branch in water and driving a metal pin into one end. Each day, you drive the pin a little deeper into the tube. Naturally, this requires a lot of precision, as the result must be a perfectly straight hollow tube. And patience is also needed, as the process can take months.

 

Quiver with arrows for a blowpipe

The arrows themselves are made of bamboo. Lipan carries a full quiver on his hip belt. Each arrow has a cylindrical plug at the rear that fits precisely into the tube of the blowpipe. This plug is made from the soft wood of the fishtail palm, a palm with leaves that resemble a fish's tail fin.

 

Lipan loads a blowpipe with an arrow, …

…aims, and shoots,

Lipan will demonstrate the use of the blowpipe for us. The cardboard target he has set up about ten meters away is hit flawlessly. Normally, an experienced hunter is able to kill his prey from a distance of 30 to 40 meters – silently and unseen. Petrus also gives it a try, but it turns out that the Penan are better at this than the Berewan.

Then it's our turn. The blowpipe is nearly two meters long and quite heavy. You’re supposed to hold it with both hands at the very front, without using the second hand as a forward support as you would with a rifle. Fill your lungs until your cheeks puff out, and then forcefully inject that air volume into the tube. So much for the theory. In practice, there are variations, some more efficient than others. But we do fairly well.

 

Not so bad

Fishtail palm

Papayas

Shortly after six, we return to the hotel. Dozens of little birds skim low over our heads in the evening twilight as we head toward the dinner buffet.

But the day isn’t over yet. Just before eight, Petrus is ready again with his fleet of longboats for a night trip on the Melinau. This time, we head upstream.

Above us unfolds a flawless starry sky

Above us unfolds a flawless starry sky, with Sirius nearly at the zenith, the Southern Cross low on the southern horizon, and Orion lying flat on his side in the west.

The beam from Petrus’s powerful flashlight nervously dances over the green foliage, searching for living creatures. Lianas hang low over the water, eerily reflected in the ripple-free surface.

On a bare branch, a kingfisher sits sleeping. Further on, a flycatcher shows only the least attractive side of itself. Despite the sounds they make, most creatures remain invisible. It can’t be a party every day.

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Tuesday, March 29 | Gunung Mulu National Park

The main reason to come to Gunung Mulu National Park is the limestone caves. They are said to be among the most spectacular in the world. Since 2005, they have been part of the World Heritage.

 

Melinau River, Gunung Mulu (in the distance)

Just before nine, we set out with our fleet of longboats, heading upstream via the Melinau. The sound of cicadas continuously swells and diminishes depending on whether we approach a tree or leave it behind us. Sometimes it is difficult to navigate the shallow waters. The boatman, standing next to his motor, carefully follows Petrus’s instructions at the front of the boat. We frequently get stuck and both men have to get into the water to free the boat.

 

Melinau River

The low water levels are reportedly due to El Niño. While under normal circumstances, the seawater off the west coast of South America is quite cold – thanks to the Humboldt Current – during an El Niño period, it becomes significantly warmer. The reason is unknown, but the consequences are substantial and sometimes catastrophic. Locally, there is less plankton, fewer fish, and reduced income for fishermen. Globally, it triggers a chain reaction that disrupts high and low-pressure systems, wind patterns, and precipitation zones.

 

Melinau River

The current El Niño is described as one of the most severe ever. Fortunately, it has been in decline since early 2016. However, this means that La Niña, the counterpart of the cycle with the opposite effects, is approaching. Experts expect it to occur in the fall of 2016.

And so it is always something. But we do not let it get to us, and go ashore around half past nine. From the pier, a staircase immediately ascends steeply into the wilderness. It's clear that we're going to climb and sweat.

The presence of limestone mountains here is due to coral reefs. These established themselves here tens of millions of years ago during the Tertiary, when there was still a sea in this area. Over time, the coral reefs were buried under sediments, forming thick layers of limestone. Tectonic movements in the earth’s crust brought these layers back to the surface as hills and mountains.

This process gave rise to a spectacular karst landscape, featuring caves of all sizes, shapes, and even colours

Then erosion took over. Through cracks, carbonic acid-rich rainwater seeped into the underground in various places and began to erode the limestone. Around two million years ago, this process gave rise to a spectacular karst landscape, featuring caves of all sizes, shapes, and even colours.

One of these is Wind Cave. A wide, unlit tunnel leads us into the interior of the mountain. A dozen bats hang drowsily from the ceiling. Swifts, still catching just enough light, dart after insects and swoop through the air above our heads. Recently, coffins were discovered in this cave – a common occurrence in the caves of Borneo. Some of these coffins are a thousand years old, while others date back to the Neolithic period, around 2 500 years ago. They are generally shaped like boats.

Then, a narrow opening in the wall appears, providing access to the actual cave system. A strong draft blows through, as the cave evidently has two openings. Now we understand how Wind Cave got its name.

The limestone caves are said to be among the most spectacular in the world

Wind Cave – Moonmilk

Limestone cave

Stalactites and stalagmites are what we typically expect to find in a limestone cave. However, what we observe on the ceiling here is entirely different – a white, blobby mass of protrusions pointing in all directions. This formation is known as moonmilk, a type of calcite. Apparently, the constant draft in this area disrupts the formation of the elegant, straight dripstones. It's hard to form beautiful, straight stalactites when the wind is constantly playing with the water droplets. Bacteria also play a significant role in the formation of moonmilk.

It's hard to form beautiful, straight stalactites when the wind is constantly playing with the water droplets

Flowstones

Dripstones

A bit further on, we encounter the culprit. A wide, vertical shaft opens up to the outside, maintaining the air circulation. High above our heads, algae and lichens have settled on the steep walls, as sunlight penetrates through the shaft. This green oasis amid the cold stones has been somewhat opportunistically named the Garden of Eden.

 

Dripstone

Garden of Eden

Dripstone

Only when we descend into the King's Chamber does a classic limestone cave reveal itself beneath our feet, but on a monumental scale. Jagged stalactites and stalagmites, seemingly petrified waterfalls, and even a dripstone formation that resembles a princess from the Tang Dynasty come into view.

It's half-past ten when we exit the cave. A wooden walkway clings to the mountainside, weaving through the dense foliage. Smooth, upright limestone formations with wavy surfaces and razor-sharp ridges catch our attention. These are miniature versions of the famous pinnacles found higher up on the mountain. There are hundreds of them, some reaching up to 45 meters in height, but getting to that spot requires quite a strenuous climb.

 

Pinnacles

We pause briefly in the shelter of a waterhole below. The crystal-clear water originates from the cave. A few specimens of the hyperkinetic Rajah Brooke's birdwing flutter energetically among the bushes. It is entirely fitting that this beautiful page has been declared Malaysia's national butterfly. Not only does it impress with its wingspan of 15 to 17 cm, but its vibrant colours are equally striking – a bright red head on a black body, a touch of blue, and seven fluorescent green teeth on each wing. Unfortunately, this makes it incredibly popular, with tens of thousands reportedly ending up in framed displays behind glass each year, their wings spread wide.

Tens of thousands reportedly end up in framed displays behind glass each year, their wings spread wide

Then, the path takes a steep ascent once more. A wooden staircase with nearly 200 steps leads us to Clearwater Cave. This is one of the most extensive cave systems in the world, first thoroughly explored by an expedition in 1977-1978. The exact extent of the system is still debated – partly because new branches are continuously being discovered. Currently, about 215 km have been mapped.

 

Clearwater Cave

The fact that the caves of Mulu are so massive is no coincidence. First of all, the area receives substantial rainfall, meaning enormous amounts of water seep into the limestone. Additionally, this water is relatively warm, which accelerates erosion. Finally, the limestone at Mulu is quite hard, so caves here rarely collapse.

 

Clearwater Cave

A wide shaft leads diagonally downwards into the cave system. Particularly noteworthy is the presence of phytokarst not far from the entrance. This is a form of biokarst where living organisms influence the deposition of limestone.

Similar formations have been observed only in Ireland and Venezuela

Clearwater Cave

Needles of phytokarst (photokarren)

Here, cyanobacteria play a role. They are capable of photosynthesis but, of course, require sunlight. The razor-sharp needles of the phytokarst apparently all point neatly in the direction of the entrance – the only place where light enters. That means the cyanobacteria manage to direct erosion in that direction. These structures are also known as photokarren. Similar formations have been observed only in Ireland and Venezuela.

Another unique feature of Clearwater Cave is the river that flows through it. As we descend, it seems as though water once flowed downward through this passage. But the truth is quite the opposite. During times of great water influx, water surged upwards through this passage, as evidenced by the sediment deposits.

Then, another enormous chamber unfolds before our eyes. A comfortable path winds through it in a loop. We descend along the river, climb back up, and marvel at the bizarre structures, the immense scale, and the fascinating colours.

 

Least pygmy squirrel

We return to the waterhole for a picnic – and a swim, for those interested. Petrus and his younger brother Noah have prepared a delicious lunch. The colourful Rajah Brooke’s birdwing is scarcely seen now. A least pygmy squirrel clings nervously to a tall tree, clearly unimpressed by our attention.

We take a brief rest at the hotel, only to soon set off again. After all, there are still some caves left to explore. The bus takes us to the national park’s headquarters. It's almost three o'clock as we cross the Melinau River via a wide suspension bridge. A convenient wooden walkway then leads us through the rainforest toward Deer Cave.

What characterizes a rainforest most of all is – surprise, surprise – rain. A typical rainforest expects to receive between 1 750 and 2 000 mm of rain per year, though some areas have to endure up to 10 000 mm annually. In the tropics, this is accompanied by a humidity level of at least 70 % and daily temperatures that range from 25 to 35 °C.

The true giants of the rainforest reach an average height of 50 meters.

But the rainforest is not a uniform entity. Various layers of vegetation are stacked upon one another, each layer with its own unique ecosystem, where specific plants and animals find their favourite spots. Massive canopies rise 30 to 40 meters above the ground, forming the roof of the rainforest. However, the true giants of the rainforest tower above even these, with colossal trees that reach an average height of 50 meters. Below these, there's a layer of shrubs, climbing plants, and small trees, where birds, small mammals, and reptiles find their homes.

Finally, there's the ground layer, where plant life struggles to survive. Sunlight hardly penetrates here, nutrients are washed away by the rain, and dead material decomposes too quickly in the warm, moist environment to be of much use – only fungi and moulds thrive under these conditions. Very few plants manage to survive here, except in open areas or near rivers and swamps.

In search of stability, the trees have developed buttress roots, which sometimes rise five meters above the ground

The soil contains barely any minerals. Deep roots are of no use here. In search of some stability, the trees have developed buttress roots, huge structures that sometimes rise five meters above the ground.

 

Fruit of banana tree

Orchid

To start farming on such infertile soil, you must be quite mad. Yet, that is exactly what is happening. The rainforest is increasingly being cleared to make way for palm oil plantations. While the climate may be favourable, the oil palms cannot survive without intensive fertilization.

No less than 280 tree species can be found in just one hectare of rainforest

Logging and mining are also relentlessly consuming the rainforest day by day. As a result, a biodiversity unmatched anywhere else in the world is at risk of disappearing – no less than 280 tree species can be found in just one hectare (2,47 acre) of rainforest.

 

Green crested lizard

For now, however, we don't see much of that immense animal biodiversity. At most, a solitary singing cicada, or a moulted cicada shell clinging to a tree trunk.

 

Cicada

Or a red-and-black banded millipede that slowly crawls along the edge of a leaf. It differs from a centipede by the fact that each segment of its long body has two pairs of legs instead of one.

 

Stick insect

A stick insect lives up to its name. It's nothing more than a bare, cylindrical stick on legs, but in tropical format.

 

Green crested lizard

From the branches of a patch of mangrove forest, a green crested lizard watches us suspiciously. Just a moment ago, it caught an insect.

 

Pit viper

A pit viper lies motionless on the leaves of a large shrub, waiting for its lunch to appear. We probably won't get to see its distant relative, the slender green paradise tree snake. A pity, because it is known for its ability to glide by flattening its body into a ribbon when it falls from a high tree, steering itself in a chosen direction. It can reportedly cover up to a hundred meters this way.

 

Entrance to Deer Cave

Quite suddenly, a limestone cliff rises vertically before us. This marks the end of our nearly four-kilometre walk. A dark spot in the whitish-grey rock, several dozen meters high, marks the entrance to Deer Cave. What we don't yet realize from this distance are the colossal dimensions of that entrance.

The bats devour fifteen tons of mosquitoes every night

Lang’s Cave – Bats

But first, we make a short visit to the nearby Lang's Cave. A handful of bats are huddled closely together in a hollow in the ceiling. A bit further along, a swiftlet has taken over a hollow. It has built its nest there. We can just make out the heads of two young birds.

 

Lang’s Cave – Swiftlet with two young

The cave was named after Lang Belarek, who discovered it in 1977. It may not be the largest cave in the park – barely 240 meters deep – but we're told it’s one of the most beautiful.

Some delicate structures hang from the ceiling as if they were crystal spider webs

Lang’s Cave – Flowstone		Flowstones
		Straws

And that turns out to be true. As we venture deeper into the cave, we find ourselves increasingly captivated by the stalactites, the petrified waterfalls, the knobby pillars, and the undulating curtains in their rich variety of colour tones – reddish-brown from iron sandstone, blue-grey from volcanic ash, green from algae and moss, and black-brown from bat droppings. Some delicate structures hang from the ceiling as if they were crystal spider webs.

Then we climb up to Deer Cave. Massive boulders partly obscure the entrance from view, yet the colossal dimensions of the opening immediately set the tone – 170 meters wide, 120 meters high. We can easily recognize the profile of Abraham Lincoln in one of those boulders.

 

Deer Cave

This is said to be the largest single cave passage in the world. Moving upstream along a gently babbling stream, we venture further inside. Nowhere does the ceiling drop below 90 meters. In the crystal-clear water, we can spot small fish. The fact that this little stream was once able to carve out such an enormous passage is a minor miracle. That this structure has remained virtually unchanged for thousands of years is even more remarkable.

Two to three million bats call this cave home. For anyone who doubts that, they need only look at the layer of guano on the ground and catch a whiff of the accompanying scent. This guano serves as an almost inexhaustible food source for cockroaches, beetles, and other insects, which are in turn hunted by centipedes and spiders – sometimes as large as a fist. Snakes, on the other hand, take care of the remains of bats that have died or had an unfortunate fall. The cave even indirectly owes its name to the guano. Deer used to come here to supplement their plant-based diet with the salt that crystallized from the guano.

Two to three million bats call this cave home. Later, when dusk falls, all those bats will go hunting together – mosquitoes beware

Later, when dusk falls, all those bats will go hunting together – mosquitoes beware. It’s an unparalleled spectacle that we’re already looking forward to. Literally millions of bats will leave the cave, forming a swirling ribbon as if a gigantic corkscrew is emerging from the cave entrance. With those erratic movements, they try to throw off hungry bat hawks and peregrine falcons. After all, every bird of prey in the vicinity knows all too well what a feast awaits here in the evening twilight.

The bats devour fifteen tons of mosquitoes every night. Apparently, someone once calculated that. Whether it’s accurate, we don’t know, but we can’t deny it – we don't have any mosquito bites here.

 

Deer Cave

Only when it rains do the bats stay in place, as they rely on echolocation to locate their prey. With this technique, they can hardly distinguish a mosquito from a raindrop. And of course, a bat isn't going to make a fool of itself by snapping at raindrops in the open air.

 

Garden of Eden

Meanwhile, we continue to penetrate deeper into Deer Cave. A staircase leads to a platform where we take in the immense surroundings. In the distance, light shines at the end of the tunnel. Thousands of years ago, a sinkhole formed there, causing the ceiling to collapse. It's a shame, because if this doline hadn't existed, the cave would have been twice as long. Lush green patches have since formed on the walls of the shaft. Once again, the name Garden of Eden was chosen for this spot.

 

Eve's Shower

Bloodsucking insect

The cave floor is strewn with boulders that were once carried in by the river. Two tubular structures hang from the ceiling, sensationally named Eve's Showers – there’s no shortage of biblical references here. But anyone hoping to see Eve in action will be disappointed; apparently, she’s not present today. Bloodsucking insects are, though, and the railings of the stairs are full of them.

Just before half-past five, we find ourselves again at the foot of the limestone cliffs. The main spectacle of the day is about to begin – the swirling dance of the bats. It's a regular occurrence here, and they've even set up a small viewing platform. About sixty bat watchers have already found a spot.

High in the sky, a hungry bat hawk shares our frustration

For now, nothing is happening. After three-quarters of an hour, that changes. A few raindrops begin to fall from the sky. Immediately, all the Asian people leave – a bad sign. The Westerners stubbornly keep waiting, against better judgment. Another three-quarters of an hour later, they finally decide that no bats will appear, even though it's not raining. We call it a day, and high in the sky, a hungry bat hawk shares our frustration.

Darkness quickly falls over the rainforest. We stroll back to the headquarters along the boardwalk, occasionally catching glimpses of some of the many exotic creatures that swarm here in the light of our flashlights.

 

Moth

Millipede

A large white moth hangs motionless among the foliage, its wings adorned with a fine purple edge. A caterpillar and a red millipede leisurely crawl toward an unknown destination.

 

Tree frog

Stick insect (Hoploclonia)

A tree frog observes us from a hollow in the tree, likely with water within reach.

The walking sticks belonging to the genus Hoploclonia are beyond belief. They resemble infernal creatures that seem to have just escaped from a painting by Hieronymus Bosch.

They resemble infernal creatures that seem to have just escaped from a painting by Hieronymus Bosch

Stick insects (Hoploclonia)

Their pockmarked bodies display all the shades of weathered wood and are covered in spikes. The male is slightly smaller than the female and hitches a ride on her back. It doesn't take much imagination to guess what his intentions are.

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Wednesday, March 30 | Gunung Mulu National Park

The bats were right. It did rain, but not until four o'clock this morning.

For a long time, little was known about what happens among the massive tree canopies in the upper layer of a rainforest. Observing tree fauna at a height of thirty to forty meters is no easy feat. It wasn’t until the 1970s that science began to delve into this area, particularly in Costa Rica.

Observing tree fauna at a height of thirty to forty meters is no easy feat

Today, we follow in their footsteps. Ranger Peter is ready to guide us on our Canopy Walk. There are sixteen suspension bridges between the trees, about 15 to 35 meters above the ground, forming a loop of roughly 480 meters. This gives us the chance to calmly observe what goes on in the treetops, without needing to perform any dangerous acrobatics.

We enter the damp rainforest along a solid boardwalk. Although it's no longer raining, humidity is everywhere. Leaves can sometimes suffer from this. If rainwater isn't drained away quickly enough, mould can form on the leaves, hindering the essential process of photosynthesis. This is why large leaves in the rainforest often develop a drip tip, a central vein that extends into a long point, allowing water to drip off easily.

Nest ferns, however, take a different approach

Nest ferns, however, take a different approach. As epiphytes, they settle on a tree and collect rainwater in a kind of basin, along with some humus. This is a bonus for a tree frog. With such a private little pond nearby, it doesn’t even need to leave its tree. It can lay its eggs there, and tadpoles can swim around to their heart’s content. In South America, bromeliads serve a similar role.

 

Pit viper

We can barely distinguish a green grasshopper from the leaf it's sitting on. A pit viper lies motionless on the leaves of a large fern.

In front of us, the towering buttress roots of a billian tree rise up, as tall as a house. This relatively rare tree, also known as Bornean ironwood, is one of the most durable and heaviest types of wood in the world. Peter estimates the tropical giant to be about two to three hundred years old and roughly 45 meters tall.

This brings us to the starting point of the Canopy Walk. No more than two people on the same suspension bridge at a time, Peter warns us, as the bridges aren’t designed for more. And no more than four people on a platform at once, he adds, as that would be too heavy a load. He continues by advising us to hold onto the railings along the way, as losing your balance is easy. Except if the railing moves or bites, he qualifies with a smile, because then you’re not holding the railing, but some living creature instead. He finishes by reminding us to take care of our cameras, as he doesn’t want any of us to be the first to drop one today.

If the railing moves or bites, you’re not holding the railing, but some living creature instead

Canopy Walk

Feeling completely reassured, we start the sky walk. The suspension bridges may be a bit narrow, but they appear sturdy. Falling is nearly impossible; the metal mesh on both sides reaches up to our navels.

We are enveloped by dense foliage on all sides, with no two trees alike. Giant ferns, epiphytes, climbing plants, ficus trees, and lianas make the green wilderness even more chaotic. It must have been quite a feat to assemble these suspension bridges.

 

 

Here and there, tropical giants rise above the canopy. It's well-known that tall trees catch a lot of wind, but they also have to endure the harsh tropical sun. Their pale, relatively smooth bark absorbs as little heat as possible.

Lianas are abundant in the lower vegetation layer. They have twisted their way upward by using trees as support. In this unforgiving environment, everything revolves around sunlight. Once a liana reaches the tree canopy, it continues to grow horizontally, stretching from tree to tree, sometimes over a distance of a thousand meters.

However, trees sometimes fall, and a foresighted liana takes precautions. It regularly generates a branch that seeks its way to the ground and takes root there. If the liana is split in two by a falling tree, both parts can survive. But if it holds its ground, it might drag other trees down with it in its fall. Such is the strength of this woody climbing plant.

 

It’s convenient to have lianas as expressways between the trees

It’s convenient to have lianas as expressways between the trees. Animals can easily move from one tree to another without ever setting foot on the ground – a place where danger always lurks. But swinging from liana to liana from tree to tree? That’s completely out of the question. Even if your name is Tarzan and you let out alien screams

Strangling trees approach the fight for sunlight in a very different way. As soon as the seed of this ficus lands on a tree, the death sentence for that tree is signed – thanks to the bird or squirrel that acted as its mail carrier. The unwilling host tree must watch passively as the ficus’s roots find their way downward. Once they reach the ground, they begin to draw nutrients, at the expense of the host tree. The growth continues upward. The ficus starts to develop its own leaves while its roots grow thicker and encircle the host tree in a strangling grip. Growth becomes impossible; sunlight and nutrients no longer reach the host tree, and it dies. Ironically, its decay provides the nutrients the ficus needs to grow even higher.

 

Mating cicadas

In short, trees and plants are abundant here. However, our untrained eyes haven’t spotted any animals so far. No monkeys or hornbills, not even a lizard or oversized insect – except for a pair of singing cicadas mating right under our noses on a tree.

For an early lunch, we are served the famous massaman curry, a dish of chicken, potatoes, peanuts or cashews, and onions in a coconut milk curry, flavoured with cardamom, star anise, cinnamon, chili peppers, tamarind, and more. The dish is said to originate from 17th-century Siam but is now incredibly popular throughout Southeast Asia. In 2011, it even topped CNN’s list of the World’s 50 Most Delicious Foods.

In 2011, the dish even topped CNN’s list of the World’s 50 Most Delicious Foods

Our paradise stay in Mulu comes to an end. For the last time, the shuttle bus takes us to the airport. Shortly after one o’clock, the Mulu appears on the tarmac, an ATR72 from MasWings.

Less than half an hour later, we reluctantly leave sunny Mulu behind and head towards the southern part of the Sarawak province. Below us, we recognize the muddy brown Baram River meandering broadly through the broccoli-like forest.

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Jaak Palmans
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The land of the White Rajahs