Borneo—the world’s third largest island after Greenland and New Guinea—holds six percent of the world’s species of plants and animals. Shared by Indonesia, Malaysia and Brunei, it is home to about 2,000 types of trees, more than 350 species of birds, about 150 types of reptiles and 210 mammal species, including 44 only found on the island. Many animals such as pygmy elephants, Sumatran rhinos, orangutans as well as the clouded leopard, the sun bear and the Bornean gibbon top the list of Borneo’s endangered species.

A total of 361 new species were discovered between 1995 and 2005. Lewis Smith and Lucy Alexander wrote in The Times, “The remote and inaccessible forests in the heart of Borneo are one of the world’s final frontiers for science and many undiscovered species are still waiting to be found.” WWF reported in April last year that at least 361 species had been newly identified on the island between 1994 and 2004, a rate of three animals and plants a month. Borneo’s estimated total of 15,000 plants is thought to be the highest plant diversity of any region on Earth. It has the highest documented tree diversity in the world, at 1,175 species in a 52-hectare plot. The island is one of two places where the orang-utan still survives, though they are threatened with catastrophic population loss because of deforestation. [Source: Lewis Smith and Lucy Alexander, The Times, December 18, 2006 /]

On hunting on Borneo in the 1840s, Henry Keppel wrote in “Expedition to Borneo of H.M.S. Dido for the Suppression of Piracy”: “But, while on the subject, I may mention that of pig- shooting, which I found an amusement not to be despised, especially if you approach your game before life is extinct. The jaws are long, tusks also, and sharp as a razor; and when once wounded, the animals evince a strong inclination to return the compliment: they are active, cunning, and very fast. I shot several at different times. The natives also describe a very formidable beast, the size of a large bullock, found further to the northward, which they appear to hold in great dread. This I conceive to be a sort of bison ; and if so, the sporting in Borneo altogether is not so bad.” [Source: “The Expedition to Borneo of H.M.S. Dido For the Suppression of Piracy” by Henry Keppel and James Brooke (1847)-]

See Asian Animals

Borneo Rainforests Full of Rare Species

Diyan Jari and Reuben Carde of Reuters wrote: “About three years ago, wildlife researchers photographed a mysterious fox-like mammal on the Indonesian part of Borneo island. They believed it was the first discovery of a new carnivore species there in over a century. Since then, more new species of plants and animals have been found and conservationists believe Borneo, the world’s third-largest island, is a treasure trove of exotic plants and animals waiting to be discovered. [Source: Diyan Jari and Reuben Carder, Reuters, March 29, 2006 \~/]

“The new finds were all the more remarkable after decades of deforestation by loggers, slash-and-burn farming, creation of vast oil palm plantations, as well as rampant poaching. Conservationists hope that Borneo will reveal many more secrets, despite the myriad threats to its unique flora and fauna. “There is vast potential,” said Gusti Sutedja, WWF Indonesia’s project director for Kayan Mentarang national park, a sprawling reserve on the island where the new mammal, nicknamed the Bornean Red Carnivore, was photographed in a night-time camera trap. The animal itself is so rare, it’s never been captured. \~/

“In 2003, we conducted joint operations with Malaysian scientists and discovered many unknown species of lower plants. Three frogs discovered are being tested by German researchers. We also recorded five new birds in a forest survey in 2003.” Some conservationists believe Borneo could be the next “Lost World” after the recent discovery of a host of butterflies, birds and frogs in another Indonesian jungle on the island of New Guinea.” \~/

Borneo has more species of tree shrew than anywhere else on the world. Tree shrews are not shrews and most species do not live in trees. They are generally hyper creatures that belong to their owner order (Scandentia). The local Bahasa Indonesian word for them, “tupai”, is the same word used for squirrels.

Deforestation of Borneo

Since 1996 Indonesia has lost an average of nine million acres (two million hectares) of forest a year. Today only half of Borneo's original forest cover remains, according to WWF. Large swaths of forest have been cleared for timber, rubber, oil palm and pulp production. Borneo's lowland forests are primarily cleared for oil palm plantations. The rainforest-covered mountains are rich in coal and several mining companies already hold access rights. Gold mining is conducted throughout Kalimantan, Indonesia’s portion’s Borneo.

Diyan Jari and Reuben Carde of Reuters wrote: “Environmentalists say the island, described by Charles Darwin as “one great untidy luxuriant hothouse made by nature for herself,” is being stripped of vast swathes of forests by loggers. Mining, lax law enforcement and corruption are also threats. According to some estimates, Borneo loses forests equivalent to an area of about a third of Switzerland every year, or at a rate of 1.3 million ha (3.2 million acres), much of it to feed the voracious appetite for timber in the West and Asia.

“Indonesia’s forests are being destroyed at a rate of 2 million ha (4.9 million acres) a year,” said Indonesian forestry consultant Dwi R. Muhtaman. “Within a short time the forest in low-lying areas (of Borneo) will be gone.” [Source: Diyan Jari and Reuben Carder, Reuters, March 29, 2006 \~/]

“WWF’s Sutedja did not have a precise figure, but he estimated the rate of deforestation in Borneo was the “the equivalent of one football field per day.” In addition to logging, Indonesia’s plans to develop a major palm oil plantation in the heart of Borneo near the border with Malaysia also threaten to devastate some of the last remaining natural forests in Southeast Asia. The area is remote highland forest from which many of the island’s largest rivers originate and has so far managed to remain intact because of its rugged terrain and distance from the coast. “There is opposition from most environmental NGOs. Their research says that areas of natural forest could be converted, and the project could affect rivers,” Sutedja said. “Flooding could occur, which would affect the indigenous Dayak people who live downstream,” he said, adding that WWF did not oppose the plan, but was concerned it be carried out in accordance with environmental principles.\~/

“Environment Minister Rachmat Witoelar said the government plan to open major palm oil plantations had taken into account his ministry’s concerns.“We will start by making use (of) the areas that are already ready for planting. I strongly oppose … cutting down forest for the replanting of palm oil plantations, which does not make sense,” he told Reuters. \~/

Borneo’s Wildlife Threatened by Deforestation

Diyan Jari and Reuben Carde of Reuters wrote: “Environmentalists say they are particularly worried as island ecosystems are known as much for their fragility as their ability to harbor rare animals and plants.Of approximately 800 species extinctions worldwide since accurate scientific recording began in 1500, the vast majority have been from island ecosystems, the World Conservation Union says. Green groups say hundreds of orangutans are killed or captured every year on the Indonesian part of Borneo as part of an illegal trade that is driving the primates toward extinction. \~/

“According to a study by WWF International and wildlife trade monitor TRAFFIC, between 200 and 500 Borneo orangutans are traded in various parts of Indonesia each year. The vast majority are infants sold as pets. WWF International estimates poachers have also killed most endangered rhinos in Borneo and only about 13 might have survived. “The current situation will continue until the forest is gone,” Muhtaman said.” \~/

Exotic Species in Borneo

Lewis Smith and Lucy Alexander wrote in The Times, “Once described by Charles Dickens as a “great wild untidy luxuriant hothouse made by Nature for herself”, Borneo is a well-established home to some of the world’s most exotic species. But even that reputation could not prepare scientists for the extraordinary range of plants and animals newly identified on the island in recent years. Fighting fish and the world’s second smallest vertebrate are among more than 50 species to have been discovered in the past 17 months. They include 2 frogs, a plant that grows only a single leaf, 16 species of ginger, 3 types of tree and 30 fish. [Source: Lewis Smith and Lucy Alexander, The Times, December 18, 2006 /]

“Among the fish discovered during zoological expeditions to Borneo was a miniature species, Paedocypris micromegethes, which, at 0.35in long (8.8mm), is the second smallest vertebrate in the world. It lives in highly acidic peat bogs found in shaded forest areas, either in pools or near the bottom of slow-moving streams. Its cousin, Paedocypris progenetica, is the smallest vertebrate, at 0.31in. WWF said that even though the fish had only just been identified, it is already under threat because of habitat loss. “Many of the peat swamps this recent research surveyed throughout South-East Asia no longer exist and their fauna is eradicated. All the endemic fish species restricted to peat swamp forests of Borneo are thus highly endangered,” the authors said. /

“Scientists expect that thousands more species are still to be identified and studied, according to a report published today by WWF, the world’s largest independent conservation organisation. From July 2005 to September 2006, 52 animals and plants were newly identified, according to WWF, many within a 136,000 square mile mountainous region known as the Heart of Borneo. Six Siamese fighting fish, including one with iridescent blue-green markings, were found. These are unusually aggressive fish that frequently flare their gills and fins when they encounter each other. /

“Other aquatic species included a catfish, Glyptothorax exodon, with protruding teeth and a sticky belly that enables it to cling to rocks in fast-flowing and turbulent streams. A green-eyed tree frog, Polypedates chlorophthalmus, another with an extra-wide head, Rhacophorus gadingensis, and a fish, Nandus prolixus, which looks like a dead leaf, were among the other animals discovered. One of the plants identified by scientists, Schumannianthus monophyllus, has bright white flowers accompanied by a single leaf. It has long been known by the native Iban peoples, who use the leaf to wrap sticky rice at a festival. The new species of ginger more than double the entire number of the Etlingera species found to date. “These discoveries reaffirm Borneo’s position as one of the most important centres of biodiversity in the world,” Stuart Chapman, international co-ordinator of the WWF’s Heart of Borneo programme, said. "The remote and inaccessible forests in the Heart of Borneo are one of the world's final frontiers for science." /

John Roach wrote in National Geographic News, “Borneo's geography is also extremely diverse, making for hundreds of unique habitats that house unique creatures adapted to these niches. Many of the new species are isolated to a single river or a side of a mountain, for example. The 0.35-inch-long (8.8-millimeter-long) fish called Paedocypris micromegethes was found in the island's acidic backwater peat swamps. The translucent fish is the second smallest vertebrate, or animal with a backbone, in the world, scientists said. It's beat only by its even smaller cousin in Sumatra, P. progenetica, which measures 0.31 inch (7.9 millimeters) long. Mark Wright, science advisor for Surrey, England-based WWF-UK, said, the discovery of three new tree species is what really puts the wealth of Borneo's biodiversity into perspective. "One fish the size of a fingernail can hide away. Trees don't move and they are really big—and we are still finding those," he said. "Heaven knows what else is there." [Source: John Roach, National Geographic News, December 19, 2006]

“Many of the species were discovered in an 85,000-square-mile (220,000-square-kilometer) mountain rain forest in a central region of the island that conservationists call the Heart of Borneo. The region is increasingly pressured by human development, so WWF is working with local officials in Indonesia, Malaysia, and Brunei to develop a series of protected areas and sustainably managed forests.[Ibid]

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.

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

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 that when the frog leaps it can glide considerable distances from one tree to another.”

Image Sources:

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, Wall Street Journal, The Atlantic Monthly, The Economist, Global Viewpoint (Christian Science Monitor), Foreign Policy, Wikipedia, BBC, CNN, and various books, websites and other publications.

Last updated June 2015

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