ANIMALS OF BORNEO: ELEPHANTS, CLOUDED LEOPARDS, FLYING LEMURS AND SNAKES

BORNEO ELEPHANTS

Borneo elephant

About 1,000 to 2,500 elephants live on Borneo. They are regarded as a distinct species, Washington Post from Asian elephants. Near all so them are in the far norther part of the island in Sabah. It was long thought that these elephants were descendants of domesticated elephants that had escaped or been set free in the forest. But DNA indicates that are genetically different from other Asian elephants and had been on Borneo at least since the last Ice Age.

Asian elephants in Borneo are smaller than other Asian elephants and have larger ears and a more rounded body. They are very gentle creatures and known for not being aggressive around people.

The WWF wildlife group estimates that fewer than 1,500 Borneo pygmy elephants exist. They live mainly in Sabah and grow to about eight feet (245 centimeters) tall, a foot or two shorter than mainland Asian elephants. Known for their babyish faces, large ears and long tails, pygmy elephants were found to be a distinct subspecies only in 2003, after DNA testing. Their numbers have stabilized in recent years amid conservation efforts to protect their jungle habitats from being torn down for plantations and development projects.

First Evidence of the Sumatran Rhino in Kalimantan in 20 years

In April 2013, Jeremy Hance of mongabay.com wrote: “Conservationists working to save the Sumatran rhinoheard good news this week as WWF-Indonesia has found evidence of at least one Sumatran rhino persisting in the Indonesian state of Kalimantan, located on the island of Borneo. Small populations of Sumatran rhinos (Dicerorhinus sumatrensis) survive on Sumatra and on Borneo (in the Malaysian state of Sabah), but this is the first time scientists have confirmed the presence of the notoriously shy animal in Kalimantan in over two decades. [Source: Jeremy Hance, mongabay.com, April 2, 2013]

"This is a very important finding to the world, and especially to Indonesia's conservation work, as this serves as a new record on the presence of Sumatran rhinos in East Kalimantan and especially in West Kutai," Bambang Noviyanto, the director for biodiversity conservation at the Forestry Ministry, said. Currently scientists estimate that there are around 200-275 Sumatran rhinos surviving in the wild.

Although WWF-Indonesia teams have not seen a rhino in Kalimantan yet, they have recently discovered footprints, mud wallows, tree markings, and signs of rhino-feeding. There is no information yet on whether this is just one rhino or a group of survivors. "The fact that this discovery comes more than a decade after the last evidence of the species in Kalimantan, despite the opening up of previously remote areas during that period, suggests that this might be just one or a small number of individuals," explains Payne. "If so, they might not have been breeding. There may be inbreeding, or a skewed sex ratio, or simply old or otherwise infertile rhinos."

Payne's organization, Borneo Rhino Alliance (BORA), is working to breed Sumatran rhinos in large semi-wild enclosures in Sabah. Currently, BORA has two rhinos, a male (Tam) and a female (Puntung). Tam was captured after he wandered into a palm oil plantation with an injured foot, while Puntung was taken from the wild when it was realized she was alone in a forest fragment with no chance of meeting a male for breeding. Payne and a group of scientists are now trying to breed the pair. A similar breeding program on Sumatra last year saw the birth of the first Sumatran rhino calf in captivity since 2001 and only the fourth in the last hundred years. However, more rhinos are likely needed if the breeding programs in Sumatran and Sabah are to be successful in the long-term.

For now, WWF-Indonesia conservationists are working to determine just how many rhinos might persist in East Kalimantan and work with local communities to protect the area. "Rhinos, dolphins, clouded leopards and local buffalo are among God's creations that are getting rare, but apparently they're still alive in West Kutai," Ismael Thomas SH. M.Si, the head of the West Kutai district, said. "We must protect them, and the communities must live in harmony with nature."

New Species of Clouded Leopard Found on Borneo

Borneo clouded leopard

The cloud leopards of Borneo and Sumatra are slightly darker than mainland species and have smaller and different-shaped cloud-like markings. In 1823, a zoologist described them as a separate series but later the designation was changed to a subspecies, In the later 2000s, DNA analysis found that DNA of clouded leopards from Borneo-Sumatra are is as different from mainland clouded leopards as that of lions and tigers and this the Borneo-Sumatra clouded leopards was declared a new species: the Borneo cloud leopard (or Sunderland cloud leopard).

The World Wildlife Fund said American scientists compared the DNA of the clouded leopard with that of its mainland cousin and determined the two populations diverged some 1.4 million years ago. "Genetic research results clearly indicate that the clouded leopard of Borneo should be considered a separate species," WWF quoted Dr. Stephen O'Brien of the U.S. National Cancer Institute, which carried out the tests, as saying. [Source: AP, March 15, 2007[

The clouded leopard is Borneo's largest predator, has the longest canine teeth relative to its size of any cat, and can grow as large as a small panther. There are estimated to be between 5,000 and 11,000 of these animals left in Borneo's rain forests, which are threatened by logging and are believed to hold many more undiscovered species, WWF said. [Ibid]

Andrew Kitchener, a Scottish scientist who led a study of the markings of the Borneo cloud leopard, told the Times of London that the Borneo leopard has smaller cloud-shaped markings than the mainland cat, a double stripe along the back instead of a single one, more spots within each cloud and a darker coloration. “The moment we started comparing the skins, ot was clear we were comparing two species.”

Residing mainly in trees the Sunderland clouded leopards is rarely seem and few of them are in captivity. In 2010 one was filmed for the first time, AFP reported: The leopard, a healthy-looking animal a metre long (3 feet) and weighing about 40 kilos (90 pounds) was caught on video at night at the Dermakot Forest Reserve in Malaysian Borneo's Sabah state. "What surprised us was that while clouded leopards are very elusive cats, this one was not scared at all," said Azlan Mohamed, a field scientist with University Sabah Malaysia. "Despite our powerful spot lights and the roar of our vehicle's engine, it walked around our vehicle calmly," he told AFP. "It is rare to see the big cat in the wild. These cats are usually shy of humans, it was by chance we caught it on video." [Source: AFP, February 16, 2010]

Flying Animals of Borneo

Borneo arguable has the world’s most diverse group of flying animals other than birds, insects and bats. The animals include flying frogs, flying snakes and flying lizards. They don’t fly exactly; they glide like flying squirrels. They are difficult to observe because they are well camouflaged, they mostly come out at night and they spend much of their time in the upper canopy. [Source: Tim Laman, National Geographic, October 2000]

There are 30 or so species of gliding animals in Borneo. Why does Borneo have some many gliders and the Amazon forests have none and Africa forests only has only a few? Some scientist believe this is because Borneo rain forests are dominated by giant dipterocarp trees, which fruit infrequently and unpredictably, and to survive animals have to work harder and travel further to get food—and gliding is an ideal way to do this as animals don’t have to make time consuming trips the ground; they can simply glide from tree to tree.

How Flying Animals of Borneo of Glide

Flying squirrels and animals like them don’t flap wings, develop thrust or catch thermals. They just glide. Some drop like a stone to gather speed before going into their glide. Most turn by lowering one arm, shifting their body weight or adjusting their tails. Before they take off flying squirrels often pause and bob their head. Some scientists believe they are triangulating the distance to their destination.

paradise tree snake in mid-glide

It is not known exactly why flying squirrels developed their ability. Gliding may be the most energy efficient way to get from one tree to another. It also may help them escape from predators or locate scarce food sources. Biologist believe that the flying squirrel’s ability to glide developed naturally over time among animals that spend a lot of time jumping from tree branch to tree branch. A wide variety of creatures, including marsupials, lizards, frogs and even snakes have developed this ability independently.

The wing-like skin membranes possessed by flying squirrels are called patagiums. They create a square-shaped flying surface and have small upward curving flaps that appear to reduce drag and stabilize and control the glide. Patagiums have been investigated but not placed on a flying device by plane designers.

All flying squirrels have a membrane between their neck and fore limbs. Large ones have a membrane between their hind legs. Smaller ones don't have this. Instead they have featherlike tails. Scientists studying flying squirrels make models of flying squirrels shapes and test them in wind tunnels.

The membranes of skin stretch between the front and rear legs, supported by thick spurs on the wrists and ankles, When opened up the membrane acts like a parachute, allowing the squirrels to stretch a jump from a high spot to a long, graceful glide to a lower spot. Flying squirrels can steer in mid air by varying the tautness of their skin membrane to either side of their body. Their wide tails provide balance when they are gliding and help them brake for landings. As a general rule flying squirrels can travel three times the distance horizontally that they drop vertically. Hence a flying squirrel that drops 10 meters can glide about 30 meters horizontally.

Flying Lizards in Borneo

About three dozen related species of flying lizards — -including Draco lizards — -are found in Borneo, peninsular Malaysia, some of the islands in Indonesia, India and Australia. They generally glide from tree trunk to tree trunk like a flying squirrel and have the ability to loop around the tree for a better position.

There are both nocturnal and diurnal varieties. They forage for ants and termites. Many species are quite territorial. If a rival arrives the resident lizard will quickly swoop down next it, launching into off aggressive displays — -flicking out the triangular skin under the lizards’s chins — -until the intrude leaves. In the mating season, males stake out territories and display their prominent dewlaps to attract females and scare off rival males. Sometimes males chase each other through the air and from tree to tree.

The most common flying lizard is eight-inch-long draco volans. When at rest its greenish or greyish skin blend in well with the bark or leaves of trees. Some have bright orange patches on their flying membrane that only become exposed when they fly. The markings may scare or confuse predators. Males have a throat appendage or “fan” that is orange. Females have a fan that is blue.

The Kuhl’s flying gecko is a nocturnal predator that sits and waits for prey to come its way. When it is startled or when it needs move to a new spot it launches into the air and glides to a new place. Webbed toes and skin on the tail and legs create surface area for the lizard to help it glide. Skin flaps folded into the body emerge to create more air pressure for longer flights.

Flying Lizards in Flight

Flying lizards can glide for up to 100 feet and flit about easily from branch to branch. They create a gliding surface with skin stretched between the elongated false ribs on each side of their bodies. At rest these ribs are folded up against the body like wings. When they leap the ribs pulls forward, causing the false ribs to extend and the skin around them to open up like an umbrella. The gliding is used primarily as a way to get from places to place and quickly escape predators. It isn’t used so much to pursue prey. For that the crawl around like regular lizards although sometimes they will pounce on an insect that exposes itself within range of a quick flight. .

Describing how the Draco flying lizard flies, David Attenborough wrote, " "It's ribs are hugely elongated. When the animals is sitting quietly on a branch, they lie close to its body, parallel to its spine on which they are hinged. When it jumps, its abdominal muscles contract, drawing the ribs forward so that they fan out and expose a wide flap of brightly colored kin on either side of the body."

Flying Snakes in Borneo

gliding colugo (flying lemur)

Borneo is the home of several species of flying snake. These creatures were long regarded as fantasies created by explorers that had been in the jungle too long. The paradise tree snake of Borneo can glide from tree to tree through the upper canopy of the rain forest. It is shaped like a ribbon and has blue, green scales with flecks of red and gold. The snakes are believed to have developed their ability to fly to escape from predators but they may also their extraordinary talent to surprise prey. [Source: Tim Laman, National Geographic, October 2000]

Describing it, Tim Laman wrote in National Geographic, “The snake moved along the tree branch...Suddenly it dropped over the edge, just holding on by its tail, and then pushed off into the damp air. It changed shape as it began to drop, ribs spreading and body flattening as it swam through the air.” Flying snakes are also adept tree climbers. They can climb vertically at great speeds, Attenborough wrote, by “gripping the bark using the edge of a “broad traverse scales beneath the body and bracing itself by the coils sideways against any roughness in the bark.”

Describing a flying Borneo snake, David Attenborough wrote, "Once up in the tree it moves from one form on a branch to another by racing along a branch and launching itself off. In the air, it flattens its body so instead of being round, it is broad and ribbon like. At the same time, it draws its length into a series of S-shaped coils...When it takes off in the air, it pulls up its abdomen towards its spine so that its underside becomes concave, and bends its log body into zigzags so that it forms a squarish rectangle that is surprisingly effective in catching the air...It even seems able, by writhing, to bank and change course in mid-air so that, to some degree at least, it can determine where it will land.”

John Socha of the University of Chicago has studied the paradise tree snakes in captivity. Ones that are nudged off a perch dangle like a “J” and fling themselves upwards and away. After plunging less than 10 feet is takes on a S-shape and begins undulating in a similar fashion to the way its crawls on the ground, only more slowly and more laterally. The snakes descend at an angle as slight as 13 percent. A snake launched from 20 feet in the air can traverse a distance of 69 feet

When the paradise tree snake is on a tree or the ground its body is round like other snakes. It achieves it ribbon-like concave shaped by flaring out the ribs so that it nearly doubles it width. The flattening effect turns the snake into an airfoil and effectively doubles its underside to create a makeshift wing that is more aerodynamic than that of many birds. The S-shaped adopted by the snakes when they are in flight is similar aerodynamically to planes with slotted wings (wings with periodic gaps that give it more lift at low speeds).

Flying Frogs in Borneo

Flying frogs in Borneo use exaggerated webbed feet and lose flaps of skin on their limbs to glide from tree to tree and descend to breeding sites. They have adhesive pads on the bottom of their feet, which allows them land on the sides of trees. The harlequin tree frog is such an expert flyer it can make 180 degree bank turns. The flying frog lays its eggs on branch above pools of water. When the eggs hatch the tadpoles drop into the water.

The largest of Borneo’s flying frogs, the jade tree frog, was discovered in the 19th century by the famous naturalist Alfred Russel Wallace. It is little studied by scientists and has never been observed gliding. They spend most of their time in the upper canopy and rarely descend except to breed. These frogs have transparent skins. Before the female lays her eggs you can see them through her skin.

Describing a flying Borneo frog, David Attenborough wrote, "It has webbed toes so elongated that when it launches itself into the air, each foot acts as a parachute...so that when the frog leaps it can glide considerable distances from one tree to another.”

Insects in Borneo

Accounts of early explorers to Borneo described "ant marches," in which "glistening rivers of warrior ants, eight miles long, hundreds of yard wide and a foot deep...consumed everything in their path, then mysteriously" disappeared. On the their journey through Borneo the Blair brothers found the swarms of highly venomous brown sweat bees to be their biggest problem. They particularly like armpits and "were solely after the salt in our sweat," they said, "and settles softly all over us, like fur coats of venom." Once Loren was stung so badly in the back of the neck he went blind for almost an hour." [Source: "Ring of Fire" by Lawrence and Lorne Blair, Bantam Books, New York]

The Raja Brooke Birdwing is one of the world’s largest, rarest and most colorful butterflies. Native to the rain forest Borneo, it brilliantly colored and has a wingspan of 6 to 12 inches. It was first caught by Alfred Russell Wallace who named after a fried in Sarawak. One reason its so rarely seen is that it spends most of its time in the upper canopy.

Wallace wrote: "The beauty and brilliancy of this insect are indescribable, and none but a naturalist can understand the intense excitement I felt when I at length captured it...my heart began to beat violently, the blood rushed to my head, and I felt much more like fainting than I have done with immediate apprehension of death. I had a headache the rest of the day." Today a prepared pair of birdwing butterflies sell for up to $2,500 on the black market.

World's Longest Insect Found in Borneo

Raphael G. Satter of AP wrote: Nearly the length of a human arm, a recently identified stick bug from the island of Borneo is the world's longest insect, British scientists. The specimen was found by a local villager and handed to Malaysian amateur naturalist Datuk Chan Chew Lun in 1989, according to Philip Bragg, who formally identified the insect in this month's issue of peer-reviewed journal Zootaxa. The insect was named Phobaeticus chani, or "Chan's megastick," in Chan's honor. [Source: Raphael G. Satter, Ap, October 16, 2008]

Paul Brock, a scientific associate of the Natural History Museum in London unconnected to the animal's discovery said there was no doubt it was the longest extant insect ever found. Looking more like a solid shoot of bamboo than its smaller, frailer cousins, the dull-green insect measures about 22 inches (56.7 centimeters), if its delicate, twig-like legs are counted. There are 14 inches (35.7 centimeters) from the tip of its head to the bottom of its abdomen, beating the previous record body length, held by Phobaeticus kirbyi, also from Borneo, by about an inch (2.9 centimeters).

Stick bugs, also known as phasmids, have some of the animal kingdom's cleverest camouflage. Although some phasmids use noxious sprays or prickly spines to deter their predators, generally the bugs assume the shape of sticks and leaves to avoid drawing attention. "Their main defense is basically hanging around, looking like a twig," Brock said. "It will even sway in the wind."

For Bragg, who works as a schoolteacher and catalogues stick bugs as a hobby, the discovery showed the urgency of conservation work. "There aren't enough specialists around to work on all the insects in the world," he said. "There's going to be stuff that's extinct before anyone gets around to describing it." The Phobaeticus chani is now a part of the Natural History Museum's "Creepy Crawlies" gallery.

Image Sources: Wikimedia Commons

Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, Lonely Planet Guides, Library of Congress, Compton’s Encyclopedia, The Guardian, National Geographic, Smithsonian magazine, The New Yorker, Time, Newsweek, Reuters, AP, AFP, , Wikipedia, BBC, CNN, and various books, websites and other publications.

Last updated February 2025