Cheesemans' Ecology Safaris
Borneo: Heat, Humidity, Mud and Glorious Wildlife
This is a guest blog from longtime traveler Jack Hochfeld, who has joined us on many unforgettable journeys, from the frozen shores of Svalbard to the steamy rainforests of Borneo. With his sharp eye for detail and lyrical storytelling, Jack brings Borneo to life—capturing not only the rare and remarkable wildlife, but also the mud, the heat, the laughter, and the sheer wildness of the place. His reflections offer a rich, personal window into one of the world’s most biodiverse corners.
Borneo: Heat, Humidity, Mud and Glorious Wildlife
We arrived early for our flight, missed the boarding call, raced for the gate, and the aircraft door closed behind us. The fuel tank was overfilled, the overflow tanks needed to be drained; we began taxiing, then returned to a gate (when one became available) to repair a fault in the braking system. We were about to depart again when the ground power tripped and needed to be reset; it tripped again, and the aircraft systems shut down. We disembarked, re-boarded, and finally had an uneventful but six-hour delayed flight to Singapore. After disembarking, we collected our luggage and headed back through immigration to our departure gate for Kuala Lumpur and Borneo. We missed our overnight hotel stay in Singapore.
Borneo lays south of China, just off the equator, with Vietnam, Cambodia and Thailand to the northwest, Singapore to the west, Indonesia to the west and south, and the Philippines to the northeast. As the third-largest island in the world, Borneo was divided over several decades in the twentieth century between Brunei, Malaysia and Indonesia.
I associated Borneo with the Allies’ disastrous loss of the island during WWII, shortly after Pearl Harbor. The defence—or more accurately, the non-defence—was split between Dutch and British colonial forces. Borneo was overrun by the Japanese and later liberated in 1945 by Australian forces, overcoming stiff resistance in harsh terrain of swamps, jungles and mountains. One could only imagine how difficult and brutal the conditions must have been.
A Living Museum of Biodiversity
The rainforests of northeastern Borneo have existed continuously for over 2.5 million years, evolving into some of the most ecologically biodiverse ecosystems on Earth. A stable climate and isolation during ice ages preserved ancient lineages of plants and animals, many endemic to the region. Almost half of all endemic birds and 65% of the island’s endemic mammals are found at Kinabalu. This deep evolutionary history make the forests of Borneo not just a conservation priority but a living museum of life on Earth.
Extraordinary Wildlife
The wildlife and biodiversity are extraordinary — over 15,000 species of flowering plants, more than 600 bird species and over 220 mammals: pygmy elephants, pygmy civets, pygmy squirrels; giant squirrels, giant Atlas moths, giant centipedes, giant island flying foxes; flying squirrels, flying frogs and flying snakes. Orang meant people, utan meant forest — people of the forest.
Gibbons, small tailless apes with long arms, looked almost human. They swung through the canopy, rarely coming to the ground. They are monogamous—rare among primates—and formed lifelong partnerships. The great apes all descended from the gibbon lineage.
The tarsier is tiny, the world’s smallest monkey, with huge fixed eyes that required it to turn its entire head like an owl to change perspective—a miniature nag-apie. The mouse deer was the world’s tiniest deer. We saw him a few times but I didn’t manage a photo.
The corpse plant—the largest flowering plant in the world—wasn’t on our routing, but the forests still dazzled. Birds are spectacular, though not always easy to spot in the thick canopy: hornbills fit the same ecological niche as toucans but weren’t related—a classic case of convergent evolution. Storm’s Stork, one of the rarest and most endangered storks globally, with perhaps 200 individuals remaining, made a miraculous appearance. We saw four in one go—2% of the world’s population.
Sun bears, the smallest bears in the world, were another highlight. Their claws and teeth were so strong and sharp that they could tear into ironwood—a feat that would destroy drill bits and saws.
Layers of Forest and Habitat
The lowland forest landscape was dominated by giant dipterocarp trees, straight-trunked titans that formed the upper canopy. We visited lowland tropical rainforest, transitional coastal, peat and montane forests—each with its own distinct wildlife, atmosphere and feel. These forests were green, lush and thick, but quite different from the sprawling rainforests of the Amazon or Central America—more vertical, layered and dense.
Over 150 species of fig trees exist in Borneo, making it one of the richest regions in the world for fig diversity. These trees fruit multiple times a year, asynchronously, offering food even when other trees don’t. They support countless animals: apes, hornbills, fruit bats and insects. The elephant ear fig bears clusters of large yellow fruit (5–10 cm in diameter) directly on the trunk or lower branches.
Nipa palms were unique in preferring coastal and estuarine environments, thriving in brackish waters where rivers met the sea.
Logging and the Reality of Conservation
The government seemed committed to protecting what remained of the natural environment, but vast areas had been logged, cleared and converted into palm oil plantations. These plantations were pretty in their own way but clearly not natural. They hosted some wildlife that fed off the palm fruits. We drove through miles of plantations to reach the reserves. At the edge, the contrast was stark: one side of the road dense forest, the other side neat rows of oil palm. It made me wonder how deep the natural forest truly extended.
One proposed conservation model planted indigenous trees, grasses and forest patches within plantations—offering wildlife refuge and corridor continuity without robbing farmers of their livelihood. Scaling back plantations and reforesting, though appealing, didn’t seem realistic. Rope bridges had been strung across roads and rivers, letting isolated canopy wildlife move and access food.
Into the Heat, the Humidity — and the Mud
The heat and humidity were relentless. The forest air was still and heavy. There was no breeze, no breath. Walking generated internal heat and the illusion of a breeze. After rain, the temperature dropped but humidity soared. Clouds built in the late afternoon, but rain often came without warning. The sky could be blue while moisture seemed to be squeezed and condensed straight from the air. It was cooler on the water and, during the final leg of our journey in the highlands at Mount Kinabalu, refreshingly mild. I now understood why the British had sought refuge in the hills.
There was rain and more rain, heat, humidity and more humidity, and of course—mud. We dripped with sweat when walking, and still dripped when sitting in hides. Our clothes were saturated; my headlamp showed drops of moisture evaporating off my skin.
The mud was thick and gloopy. The road had recently been repaired, but we didn’t get more than 500 metres into a night drive before sinking axle-deep. The rescue team arrived with something like tooth floss for a rope. Our guide walked back to the lodge and returned with gumboots so we could hike out. On a night walk through the same area, he sank knee-deep in mud and immediately touched a live electric fence—after warning us not to all week.
At one point I reversed to take another route; my gumboots were sucked in and mud leaked over the tops. I was grateful I’d extended my tripod legs to save the camera from landing in the sludge.
Local Life and Lingering Histories
I’d packed long trousers and long-sleeved shirts to guard against bugs, but the insects were fewer than expected. I eventually reverted to shorts and lighter hiking gear. The heat proved a greater challenge than the insects.
A local SIM card cost $5 a month—smarter than Telstra’s $10 a day.
We met at a shelter—a pondok. In 1800s Cape Town, the same word referred to reed huts used by Malay and other enslaved peoples in colonial gardens. It appeared often in court records and was later absorbed into Afrikaans and South African English. The Afrikaans word for banana—piesang—also came from the Malay pisang, a small linguistic echo of history in the Dutch East Indies, now Indonesia.
The Caves and the Call of Birds
We visited Gomantong Caves, a UNESCO World Heritage site. Thousands of echo-locating swiftlets nested there in perpetual darkness. The cave was also home to centipedes, cockroaches and millions of bats. We hiked up 552 stairs hoping to witness the evening bat exodus, but they declined to exit before dark. Still, we watched the swifts return to nest. Abandoned nests, built from feathers, plant matter and saliva, were harvested for bird’s nest soup. Our guide had spent three months filming the BBC Planet Earth series in these very caves.
We heard a white-headed broadbill. I searched for a bird with a broad beak and a white head. It turned out to be luminous lime green—with no white head. It was Whitehead’s broadbill, named after a 19th-century naturalist.
The gibbon’s call carried for miles in long looping phrases, rising and falling—something between an oriole and a green-spotted pigeon. The orangutan was less melodic, more guttural. The leopard cat mewed softly from the undergrowth. Bird calls were often more common than sightings, but helped us locate them in the dense canopy.
There were eight species of hornbills, each with a distinct call—croaking barks, awk-awks, or piercing squawks. Their wingbeats created a loud whump-whump through the air. The rhinoceros hornbill’s ivory-colored bill was topped with a fiery-orange casque known as red ivory.
Boats, Dolphins and Squirrels
We lingered by the fishing boats to spot the Irrawaddy dolphin. These blunt-nosed, round-headed creatures lived in freshwater and surfaced with a soft puff to collect scraps from the catch.
I tried to photograph a pygmy squirrel—tiny and irresistibly cute. Every time I got him in the viewfinder, he scampered to the far side of the tree. I moved around, he darted back. We played a ridiculous game of squirrel chase that had my fellow travelers in tears of laughter.
Mount Kinabalu and Wallace's Legacy
Mount Kinabalu was Borneo’s first UNESCO World Heritage Site. When it wasn’t wrapped in cloud, its 4,095-meter peak dominated the skyline. Hikers tackled the 9.8 km trail over two days—up and down.
Darwin had hesitated to publish his theory for 18 years, fearing backlash from the church. Wallace, working independently across the Malay Archipelago—including Borneo—reached the same conclusion and wrote to Darwin. This prompted Darwin’s advisors to urge immediate publication. Numerous species in Borneo were named in Wallace’s honor.
The People and the Photographer
As it turned out, the wild man of Borneo was American.
Final Thoughts
Borneo tested the limits of comfort, patience, and camera gear — yet gave back far more than it took. Beneath the dripping humidity and sinking mud lay a world few will ever witness so intimately: ancient rainforests humming with life, creatures that defied scale and expectation, and a rhythm of wildness that made time stretch and contract.
This journey through Borneo wasn’t about checking species off a list. It was about being still, being muddy, being curious — and letting the wild speak.