You don’t have to travel far before the hotels of Malaysia’s “honeymoon island” are supplanted with the colourful low-rise farmhouses of the verdant interior. This is rural Langkawi at its most bucolic; the domain of swamp buffalo gently grazing in company of their faithful companions, the cattle egret. Heading north-west, the lowlands give way to the jagged ridges of Machinchang Cambrian Geoforest Park, a 500-million-year-old product of geological activity now carpeted by lush rainforest.

A colugo leapt from the tree canopy, sailing over our heads like a kitten strapped to a kite

Some of the holiday island’s elite properties are sandwiched between this rainforest and the north coast. Though these resorts are usually only open to guests, my guide, French primatologist and passionate conservationist Priscillia Miard, has forged relationships with the resident naturalists and we were granted access to wander through the grounds of The Andaman Resort unsupervised.

“They’ve constructed paths through the rainforest, which makes perfect ground for spotting night mammals,” Miard explained with an Attenborough-esque tone of barely supressed excitement.

The cicadas welcomed us to the rainforest with a rasping chorus. Something jumped overhead, a flying squirrel perhaps, followed closely by a pair of fruit bats that whizzed between the fishtail palms like lovers dancing. As darkness fell on the island, it grew evident that another world had awoken.

We soon met up with two of Miard’s research assistants – Fizri Zubir, a Master’s student at Universiti Sains Malaysia who is currently studying colugo behavior holding a camera and Nur Liyana Binti Khalid, who is studying forestry science at University of Malaysia Sabah sporting a headlamp as if preparing to descend into a cave. But their attention was directed upwards, the red light searching the trees like a night patrol looking for combatants in a jungle war. Miard used a thermal imaging camera to track the shadows. It wasn’t long before we found what we were looking for.

“There’s one,” said Zubir, gesturing to the trunk of an enormous tree. Through the ebbing light, a round object suspended beneath a branch was barely distinguishable, and could have easily be written-off as a jackfruit – if it didn’t begin to unfurl.

“It’s about to go through its morning ritual!” Mirad gasped in the way a proud parent might speak of their child.

The creature stretched, then clung upright against the tree with its sharp claws and began to groom. Its skin required some attention as it had, frankly, a lot of it. A membrane stretched from its neck via its hands and feet to its tail, a kite-like feature that distinguishes the colugo, once popularly known as the flying lemur, from other night gliders like the flying squirrel, which has a long tail that it uses to fan itself through the air. Because they don’t fly, nor use a tail to fan, colugos, with the logic of a hand glider launching from a hillside, typically climb high into a tree before attempting to glide. Still, their range is impressive. According to Miard they’ve been recorded gliding a full 150m, although hops of 30m or less are far more common.

After grooming itself, the colugo lifted its tail to relieve itself of yesterday’s dinner. It was hard not to draw parallels between the colugos’ habits and what we humans usually do in the morning.

“Colugos are not far removed from us,” Miard pointed out. “People used to think they were related to bats or squirrels but that’s been proven not to be the case. In fact, primates are some of their closest living relatives.”

The colugo’s missing link status – they actually belong to their own order, the dermopteran, having outlived all their closest mammalian glider cousins – is just one of their intriguing qualities, which also include feeding their young with milk excreted from glands located under their armpits; a preference of leaves and flowers to fruit; licking their eyeballs like lizards to clean them; and communicating with ultrasound (like near-blind bats) despite having good vision.

“They usually sleep on different trees from where they like to feed,” noted Miard, as a colugo leapt from the tree canopy, sailing over our heads like a kitten strapped to a kite. It landed without incident and promptly began dining al fresco on a succulent salad of leaves and a side order of mineral-rich lichen, which it ate directly from the branch.

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Humans have lived alongside colugos for centuries. They were first recorded for science in 1758 and even make an appearance in The Malay Archipelago, the seminal text by renowned British naturalist Alfred Russel Wallace who wrote in 1869: “Another curious animal, which I had met with in Singapore and in Borneo […] is the Galeopithecids, or flying lemur. This creature has a broad membrane extending all around its body to the extremities of the toes, and to the point of the rather long tail. This enables it to pass obliquely through the air from one tree to another…”

Colugos are not that uncommon either. Although the Philippine colugo is unique to just a few islands of the Philippines, the Malayan colugo is found in most forest habitats of Southeast Asia. Which raises the obvious question: why isn’t more known about them?

It’s a riddle Miard has wrestled with over the past three years while studying night mammals on the Malaysian islands of Penang and Langkawi as part of her PhD research.

“In Penang [a built-up island just 67 miles (108km) south of Langkawi] where I began my research, I was principally focused on research methodology for tracking night mammals, things like civets, slow loris, mouse deer and wild boar,” she said. “But I found colugos living everywhere. They lived in farms and in roadside gardens. But there was so much missing data. That’s what made me really interested in studying them.”

One commonly cited reason for our lingering ignorance of colugos is that they’re sensitive animals. According to Langkawi-based naturalist Irshad Mobarak, “No zoo in the world has successfully reared them in captivity.”  Their fantastic camouflage skills, nocturnality and tree habitats also allude to why they’ve evaded popular attention for so long. Plus they don’t eat us nor we them. But for a dedicated naturalist, no excuses can countervail a bewildering gap in scientific understanding.

Knowing that observation and fieldwork would be key to getting to know the colugos, Miard decamped to Langkawi in 2018, where greater forest cover and flatter land aids her research, as well as providing a secondary site to compare with her Penang findings.

With help from the Penang-based NGO, the Malaysian Primatological Society, she’s since established a Colugo Research Station in Temoyong, Langkawi, that offers a base for curious students and researchers of all disciplines to come and study colugos.

Hemmed between a mosque and a petrol station, the area around the research station is an ideal place to study how colugos are adapting to human encroachment on their turf. We headed there on our second night out, just as a loudspeaker began calling the faithful to evening prayer. Overhead, the fading sun turned the sky spectacular shades of orange then purple, the famous Langkawi sunset that is another of the island’s star natural attractions.

“These trees would all have been planted by people,” explained Miard, as we walked out of the research centre onto Bohor Tempoyak Street in the company of her research assitant Zubir. Interestingly, in Peninsular Malaysia, colugos seldom leave the forests, but on Langkawi, they go much closer to human settlements. Nobody knows why exactly. 

For an excited moment, Miard and Zubir believed they’d seen a colugo, a white moving object viewed with the thermal imaging camera. However, it turned out to be false alarm; a bird nesting in the treetop. Just as our hopes were fading, they spotted a colugo grasping a roadside trunk. On further inspection it turned out to be two: a mother and her infant child, which clung to her chest.

“Oh, look how cute they are, that little one must only be a few weeks old,” Miard said, before assuming a more professional manner. “We’ve noted they can have up to three children a year; they don’t appear to have a particular mating season.”

Before long, colugos appeared all around us, emerging from the gloom like phantoms, using the road as a kind of skyway – the gap forged by the highway a two-lane country road proving an ideal space for a gliding animal, even if near misses with passing lorries and motorbikes were commonplace.

“We’ve learned they are very social,” said Miard of the neighbourhood community. “One area can have up to 20 individuals. But we’d like to tag one to track their movements in more detail.”

Despite their manifest adaptability to various habitats, there remains a lot of concern about the threats posed to colugos in Malaysia, a country where deforestation remains a real issue.

“Habitat loss is their biggest threat,” she said. “But some farmers kill them as well.”

The slaying of colugos as pests is ironic because they are actually beneficial to the environment.

“Colugos are essential to tree productivity,” said Miard. “Consider durian, which Malaysians love. When the tree flowers, the colugos eat some of those flowers. This will result in a better quality of fruit.”

The issue of colugo awareness is where Miard’s research meets conservation, as these mysterious mammals are analogous to the health of the ecosystem. Malaysia is one of just 17 countries considered megadiverse by scientists, but it is also a fast-developing country where humans are putting increasing pressure on the natural world, particularly the jungle, which is cleared for farmland or to build housing.

To this end, the results of her research are published on the Night Spotting Project (NSP) social media pages, whose aims include “saving nocturnal mammals via research, education and community empowerment”.

Miard would also like see Langkawi reorientate itself towards more eco-tourism .

“A lot of tourists just come here and rent jet skis on Cenang Beach or go to the mall shopping for duty free goods. But Langkawi could be like Sabah [a state in eastern Malaysia] and develop tourism around nature,” she said. “Most people have no idea how rich the animal resource is. Some tourist companies such as Jungle Walla and Dave’s Adventure Tours lead nature orientated activities, but many companies are missing opportunities to do more nature-focused activities.”

“The forest hiking is incredible, but few people go into the forest except locals when hunting. This island could really be an eco-tourist hotspot,” she said, before conceiving a new moniker for “honeymoon island” as “the island of the colugo”. 

Nature’s Curiosities is a BBC Travel series that offers a close-up look at the natural world, taking adventurous travellers on an unexpected journey of exploration.

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