The little green boat gurgled and spluttered her way along the sleepy backwater that fed Borneo’s mighty Kinabatangan River. The late afternoon sun was veiled with soft cloud and was already fading into that hazy, dull light of an evening in the tropics. The gloom of the rainforest was beginning to close in on the narrow channel. The animals of the daytime would soon be sleeping, but unbeknown to me I was about to witness a pre-bedtime drama that would shame an over-sugared toddler.
The Proboscis monkeys appeared at the water’s edge in search of the best sleeping branches. They always sleep alongside the river. It gives them the comfort of one side where they are free from fear of predation. The group peacefully grazed on tender green leaves in preparation for a sleepy night ahead.
The Proboscis monkey is a truly magnificent-looking beast. Endemic to the island of Borneo, they are one of Nature’s stranger creations. The males are particularly odd, with a huge nose, fat belly, permanent scarlet erection, orange fur, centre parting, and long silver limbs.
The alpha male carefully watched over his harem of females, exactly as he did every night, but tonight something in the trees had caught his eye. The local bachelor group had moved a bit too close for comfort and one cheeky individual had his eye on Alpha’s ladies.

Alpha sat imperiously sneering at the interlopers with his pendulous proboscis wobbling impressively and his chili-red erection standing proud above coal-black testicles, flagging his masculinity for all to see. Would this nonchalant display be enough to discourage the dissent?

A fine-looking bachelor stepped forward. The fur on his back was a beautiful dark rusty orange, accentuating his superb silver Superman underpants. His snout, slightly shorter than Alpha’s prodigious proboscis, carried a battle scar that gave him the look of an aging bare-knuckle boxer. This monkey meant business!

As well as being a visual symbol of authority, a key role of that odd-looking proboscis is to help the male establish and confirm dominance by trumpeting a nasal honk. Alpha quickly realised that his authority was being challenged and that he had to rise to that challenge fast. He opened his mouth to show off his sharp teeth and then unleashed several goose honks.

Infuriatingly, the honks were met with a surly response from the bachelor. This insolence was intolerable and both monkeys broke out into a noisy tantrum, throwing themselves through the branches with the elegance, and grace of a large sack of rice.
Still, the challenge persisted and Alpha knew that he needed to do something exceptional to bring this insurrection under control. Creating some space for himself, he clambered to the tallest tree that he could find, in clear view of the females and bachelors alike. He honked at the assembly to ensure that all eyes were on him. Was he planning to show his strength and bravery by throwing himself into the river below?

Alpha looked down at the thick latte-coloured river water. It looked a long way down. On top of the height, there is the small problem of the huge Saltwater crocodiles that patrol to Kinabatangan River. These massive predators eat primates like popcorn and could be lying in wait under the opaque surface, anywhere at anytime.

With the added pressure of his ladies watching on, Alpha had the look of a person about to jump out of an airplane for the first time. It seemed like a good idea until standing on the precipice, faced with the reality of the drop below.
It appeared that Alpha was wishing he was anywhere but on that tree top. Why hadn’t he climbed a smaller tree? He looked down at the water and up at his rival. A period of stillness and silence followed, as breaths were held.
Everyone was invested in the moment. The ladies waiting to see if Alpha was still brave enough to lead them, the bachelor waited to see if this was his time. If Alpha didn’t jump now then perhaps he could finally get his turn to lead a group. I held my breath, desperately hoping to capture the moment on camera, despite the failing light and the movement of the bobbing boat.
Alpha opened his mouth wide again. Perhaps to show off his teeth, or perhaps to take a last deep breath of courage before leaning forward and hurling himself into the Bornean evening air.


The marvelous monkey stretched out his arms and legs, with a flailing tail tracing his trail through the air, and proud erection pointing to the landing spot, he plummeted toward the crocodile soup below.
An alpha male proboscis monkey is a big primate! Males have been known to grow up to 30 kg (66 lb) kg. His size is made more impressive by his beer-barrel belly. I watched in awe as this prime primate plunged downwards.

The monkey smashed through the surface of the river with as much commotion as he could possibly manage to create. The air was bristling with excitement and it seemed like the whole jungle gasped.
Could Alpha possibly survive such an impact? Would he ever surface again? Would he be a large supper for a hungry reptile?


Suddenly, away from the splash-landing zone I spotted a small head like a good-size orange drifting across the river. Alpha had survived his great leap of faith and was paddling with purpose towards the safety of the tree roots and the river bank.

To my considerable relief, Alpha dragged his soggy body out of the river. He wouldn’t be anyone’s supper tonight. He was ready to receive the respect of his rival, and adulation of his adoring harem. He received both.

He stood facing the assembled crowd and honked and huffed his celebration. He had proved himself beyond all reasonable doubt without any blows being struck.
That night he would be able to sleep soundly in the knowledge that his time as leader of the Proboscis pack was not yet done. He truly was the alpha.
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Categories: Asia




Great pictures and accompanying story! We saw proboscis a couple of years ago in Borneo, they are peculiar looking monkeys aren’t they? Maggie
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Thank you, Maggie! They are wonderfully peculiar little characters.
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Thanks for sharing your Borneo adventures. I’m knee deep in writing a novel (for ages 8 to 12) that is set mostly in Borneo with a focus on Proboscis monkeys. May the government of Malaysia work harder to preserve the habitats for these and other endangered species living on the island.
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Wonderful! Do share the name of the novel when you have finished it. Hopefully we can all continue to support the preservation of habitat and I’m sure your novel will be a contribution to this goal.
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Whew, I’m glad I can breathe again, was holding my breath for a long time there. What a remarkable event to witness. And document! I’m so thankful for you sharing experiences I will never witness in person myself. I’m glad Mr. Alpha did not become part of the crocodile food chain.
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There was a lot of breath holding that day! Not least by Alpha who definitely didn’t deserve to be croc food after his magnificent efforts ☺️
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Good to see you coming to Kinabatangan River.
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My third and hopefully not my last time.
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A Wonderful post David of a monkey I have never seen before.
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Thank you!
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Wow! What a moment. Wonderful storytelling, and your photos are magnificent. What fabulous captures of the leaping monkey! I’ve been to Kinabatangan, and saw some proboscis monkeys, but I didn’t get too any back waters.
Alison
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Thank you, Alison! I seem to remember that you were in Borneo at the start of the Covid pandemic?
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Yes it was. We just got home in time before everything shot down.
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You tell such a wonderfully dramatic tale to go along with what you have the good fortune to witness. Amazing! I can hardly imagine that leaping into the river is the pinnacle of manly achievement in the proboscis monkey world. A bizarre ritual for a bizarre being.
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Thank you, Eilene! It was a dramatic moment for sure. I was surprised that they played out that much drama with humans right beside them. A monkey that bizarre deserves a bizarre ritual, and there is something refreshing about it not needing to end in physical violence.
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Thank you for sharing this riveting tale with blow-by-blow action shots! Such a fascinating species. How do you deal with the biting insects on your nature jaunts or are they not a problem? Just curious because my forays into nature have been curtailed because I get so badly mauled and I’ve become allergic from decades of exposure, but I don’t like to use deet products. If I venture out in August here in NJ, I become the “all-you-can-eat” buffet.
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Thank you for the kind words. Very much appreciated! Honestly, this trip was tough for mosquitoes. I don’t usually do too badly but I took a few bites this time. You can’t even buy deet products in Borneo but there are natural products available. For me it was worth a few bites, but I appreciate that not everyone is in that position.
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Hi David thanks for amazing pictures and exciting narrative. Steve
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