Sumatran Orangutan | Species | WWF Sumatran Orangutan Derived from the Malay words for “person of the forest," Sumatran orangutans are critically endangered. CR Status e Habitats Tropical and Subtropical Moist Broadleaf Forests The Sumatran orangutan is almost exclusively arboreal, living among the trees of tropical rainforests. Females virtually never travel on the ground and adult males do so rarely. Sumatran orangutans are reported to have closer social ties than their Bornean cousins. This has been attributed to mass fruit on fig trees, where groups of Sumatran orangutans can come together to feed. Adult males are typically solitary while females are accompanied by offspring. Historically, the Sumatran orangutan was distributed over the entire island of Sumatra and further south into Java. The species' range is now restricted to the north of the island with a majority in the provinces of North Sumatra and Aceh. Of the nine existing populations of Sumatran orangutans, only seven have prospects of long-term viability, each with an estimated 250 or more individuals. Only three populations contain more than 1,000 orangutans.

Orangutans that were confiscated from the illegal trade or as pets are being reintroduced to Bukit Tigapuluh National Park. They number around 70 and are reproducing. Map data provided by IUCN . Places Arrival of baby orangutan is a symbol of hope for conservation in Sumatra One of the last great stands of rain forest in the deforestation hotspot of the Indonesian island of Sumatra has welcomed an exciting new addition: a baby female orangutan. The infant is the first orangutan born in the Thirty Hills conservation concession since WWF and its partners began managing the 100,000-acre forest in 2015. Continue Reading h More Stories h Why They Matter Orangutans are frugivores and play a vital role in the dispersal of seeds over a huge area. If orangutans were to disappear, so would several tree species, especially those with larger seeds. The tropical rainforests where Sumatran orangutans live are also home to other spectacular species including rare Sumatran tigers, Sumatran elephants, and Sumatran rhinoceroses. The forests orangutans call home are a vital source for fresh water.

Rivers and streams from these forests provide local communities with water for drinking, cooking, bathing, irrigation and hydroelectricity. The forests are also a valuable source for wildlife products like honey and rattan. Threats No reasonable doubt that the last individual has died EW Known only to survive in cultivation, in captivity or as a naturalised population CR Facing an extremely high risk of extinction in the Wild EN Facing a high risk of extinction in the Wild VU Facing a high risk of extinction in the Wild NT Likely to qualify for a threatened category in the near future LC Least Concern Does not qualify for Critically Endangered, Endangered, Vulnerable, or Near Threatened Human activities are destroying tropical rainforests and endangering the existence of many animal species in Indonesia. Hunting Despite legal protection in Indonesia since 1931, orangutans are still captured from the wild and kept in households as status symbols. In some areas orangutans are hunted for food. Investigations by TRAFFIC, the global wildlife monitoring network, shows that lack of law enforcement against this illegal trafficking poses a serious threat to orangutans.

Females give birth to just one infant at a time every eight or nine years, making their populations very susceptible to even very low levels of hunting. Experts estimate that even as little as 1% of females lost each year through hunting or other unnatural causes could put a population on an irreversible trajectory to extinction. Habitat Loss Orangutan habitat in north Sumatra is being lost at an extremely high rate, mainly due to fire and conversion of forests to oil palm plantations and other agricultural development. This species depends on high-quality forests. Widespread forest fires, many set deliberately to clear land for plantations, are becoming a regular disaster. Not only do fires destroy vast areas of orangutan habitat, but thousands of these slow-moving apes are thought to have burned to death, unable to escape the flames. A plan to build a major road in northern Sumatra threatens one of the largest-remaining areas of the orangutan’s habitat. Not only will the road fragment the forest, but it will also open up access for illegal logging activities and human settlements. The project is progressing despite proof that conserving the region will help long-term sustainable development.

“The fate of Sumatran orangutans is inextricably linked to the islands fast-disappearing forests. If we want to save the Sumatran orangutan we have to save their forest home.” Dr. Barney Long Asian Species Expert What WWF Is Doing Fighting Wildlife Crime WWF works with TRAFFIC, the global wildlife trade monitoring network, to help governments enforce restrictions on the trade in live animals and orangutan products. We continue to investigate the root causes of this trade and encourage stricter law enforcement. Saving Orangutan Forests WWF works with other organizations to stop Asia Pulp and Paper/ Sinar Mas Group from clearing the largest portion of natural forest remaining outside the Bukit Tigapuluh National Park. This unprotected forest provides crucial habitat for the Sumatran orangutan, as well as numerous other species. We helped develop a spatial plan based on Sumatra’s ecosystem to conserve the last stands of forests on the island. We also collaborate with various partners to protect forests in the Bukit Tigapuluh landscape, an important area where an orangutan population is being introduced.

WWF supports the Indonesian government’s 2009 commitment to reduce the country’s greenhouse gas emissions by 26% by 2020, and up to 41% with external aid. After a $1 billion pledge from Norway, the Indonesian government promised to stop granting licenses for clearing tropical and peat forests in Sumatra and elsewhere, starting in 2011. We use our expertise to help the government protect the forests and achieve emission reductions. Mitigating Human-Orangutan Conflict WWF works with Indonesian non-governmental organizations to mitigate human-orangutan conflict in and around palm oil plantations. A guide was developed that identifies management practices that will benefit conservation and industry.

ORANGUTAN ISLANDS INDONESIA - Wildlife Adventures of Orangutan in Indonesia - Orangutan Islands - Oranghutan Tours - Orangutan Tours - Orangutan Indonesia Primates - Indonesia Red Apes - Orangutan Indonesia Explore - Kalimantan Orangutan - Kalimantan Explore - Orangutan Information - Borneo Orangutan -Orang-utan - Orang Hutan - Man of the Jungle - Planet Apes - Save Orangutan Indonesia - Orangutan Borneo Tours - Orangutan Borneo Kalimantan - Tanjung Puting National Park - Orangutan Indonesia - Orangutan Primates - Indonesia Red Apes Orangutan Adventures - Orangutan Expedition - Kalimantan Orangutan - Indonesia Orangutan Specialist In Tanjung Puting National Park, We provided tours on KLOTOK river boats house to explore Sekonyer river of central south of Kalimantan Borneo.

Orangutan Islands Tours We provided Orangutan Tours in Bukit Lawang of North Sumatra and in Sekonyer River Orangutan Tanjung Puting National Park of Central South of Kalimantan Indonesia Borneo 3 Days 2 Nights Sumatra Orangutan Our Orangutan Tours 3 Days 2 Nights Including Pick p d Transfer from Kualanamu Airport of Medan in North of Sumatra Indonesia 3 Days 2 Nights Kalimantan Orangutan 3 Days 2 Nights Orangutan Tours Based on Klotok River Boat in Sekonyer River Tanjung Puting National Park of Central Kalimantan. 4 Days 3 Nights Kalimantan Orangutan 3 Days 2 Nights Orangutan Tours Either based on Klotok River Boat or Stay at Rimba Lodge in Sekonyer River Tanjung Puting National Park. 5 Days 4 Nights Kalimantan Orangutan 5 Days 4 Nights Orangutan Tours is Our Special Exploration Tours Either Stay in Rimba Lodge or Klotok River Boat in Tanjung Puting National Park.

Tanjung Puting National Orangutan Tours Tanjung Puting Natonal Park Located in Central South Kalimantan Indonesia Offer The Best Place to See Orangutan and Other Wildlifes Using Our Klotok River Boat to Explore The River of Sekonyer and its Rainforest. Sumatran Orangutan Crisis Sumatran Orangutan Crisis Print Email Sumatran Orangutan Crisis For the last eleven years, the Orang Utan Republik (first Education Initiative and now Foundation) has been working to address the Sumatran orangutan crisis, by providing local organizations on the island with grants, and supporting programs and projects that improve local people’s perceptions of, and attitudes towards, orangutans, and the importance of their forest home. The challenges OURF and other organizations face are both numerous and complex. Orangutans are the only non-human great ape found in Asia, and were once widespread throughout most of the south east of the continent, and even as far as southern China. Today, two species of orangutan exist, on the island of Borneo, which is shared between Indonesia, Malaysia and Brunei-Darussalam, and the wholly Indonesian island of Sumatra.

Previously considered endangered in Borneo ( now critically endangered as of 2016 ), where most recent estimates put the population at around 55,000, OURF has focused its efforts on the critically endangered population in Sumatra, which numbers around 14,500 (as of 2016). Sumatra is an island in western Indonesia, and the sixth largest island in the world, with a population of around 45,000,000 people. Lying in the Pacific ‘Ring of Fire’, Sumatra has been both blessed and cursed by extreme volcanic activity, which has endowed the island with fertile land and abundant tropical forests. Home to 580 bird species and 201 mammal species, 9 of them endemic to the island (WWF, 2008), Sumatra is made up of dozens of ethnic groups, who speak 52 different languages between them. Although strong local cultures and customs still exist, Islam is today the dominant religion. Like most of Indonesia, Sumatra was once covered in tropical forests, and orangutans could be found throughout the island.

Smaller, lighter colored and generally more social than the better known Bornean orangutan, today the Sumatran orangutan is found only in the island’s northern parts. Legal and illegal logging, large scale forest conversion, mining and development brought about the extinction of southern populations and continue to fragment the remaining populations. Satellite imagery shows Sumatra has lost 48% of its natural forest cover since 1985 (WFF, 2008), and it is estimated that up to 800 orangutans are being lost every year as a result of habitat destruction and hunting. With a population of just a few thousand, if the current rate of decline continues, orangutans will be extinct as a genetically viable species in Sumatra within just 10 years. A population of 14,500 can often sound large, particularly when compared to the 400 wild Sumatran tigers still surviving, or the 700 or so mountain gorillas of central Africa. However, in context, the figure is frighteningly low.

Orangutans have the longest birth interval of any land mammal, females giving birth to one young every 6-8 years, from the age of 15, and usually producing no more than 3-4 offspring in their lifetime. With such a low birth rate, they are particularly vulnerable to hunting pressure or any kind of habitat destruction. Making the Sumatran orangutan crisis even more urgent is the fact that all of the orangutans in Sumatra are scattered throughout small patches of forest, all in the north of the island, all surrounded by human settlements and plantations, all isolated from neighboring populations, and all currently under serious threat of habitat conversion. Of the 13 populations of Sumatran orangutans on the island, just 7 are considered viable, and just 3 populations contain over 1000 individuals (SOCAP Workshop Report, 2005).

The biggest stronghold of the orangutan is the Leuser Ecosystem, an area of approximately 2.6 million hectares in northern Sumatra, which contains two major volcanoes, three lakes and nine major river systems, 4.2% of all known bird species, 2.6% of all known mammals and is the only place on earth where orangutans, tigers, elephants, rhino’s and clouded leopards can be found in one area (Robertson, 2002). The ecosystem includes the 950,000 hectare Gunung Leuser National Park, which has been subjected to widespread legal and illegal logging, encroachment, palm oil conversion, forest fires and the Ladia Galaska road development, which has bisected the park in to two sections (EIA, 1999). The swamp forests on the west coast of Aceh province, which harbor the highest densities of orangutans ever recorded and 30% of all remaining Sumatran orangutans, form part of the Leuser Ecosystem, and acted as a protective buffer zone for communities during the 2004 Asian tsunami, but have historically been cleared and drained.

Two thirds of the Tripa peat swamps forests have already been converted for palm oil plantations, and the area is, as of March 2012, at the forefront of a battle between environmentalists and the governor of the local province, Aceh, after he granted an Indonesian palm oil company permission to convert the area in to a plantation, despite a moratorium on forest conversion enacted by the national government in Jakarta last year, in spite of the Leuser Ecosystems protected status, the depth of the peat in the area, which makes conversion illegal, and despite the objections of local villagers. OURF’s partners in Sumatra have begun court proceedings in Aceh to gain clarifications on the legal status of the concession, but, in the meantime, the forests in and around the concession are being converted, and fires have been documented in the areas. Conservationists warned in 2005 that if plans to convert these areas went ahead, the orangutans of the Singkil, Kluet and Tripa peat swamps could be extinct within a little as 4 years (SOCAP Workshop Report, 2005).

While efforts have so far been sufficient to ensure this hasn’t happened, much hinges on the outcome of the court proceedings, and the orangutans in this area remain severely threatened. The most southerly populations of wild orangutans in Sumatra are found in the East Sarulla and West Batang Toru forest blocks of North Sumatra province. The 54,500 hectare East Sarulla block contains 250-300 orangutans, and approximately 600-800 remain in the 81,000 hectare West Batang Toru forest block. The steep, rugged terrain of these forests has largely protected the orangutans that inhabit them from incursions, which have so far been restricted to the more accessible lowland areas, but hunting by local people, for both sustenance and for the pet trade, and illegal logging is putting increasing pressure on these populations (SOCAP Workshop Report, 2005).

For the last few years, our partners the Sumatran Orangutan Conservation Program have run the world’s only Sumatran orangutan rehabilitation and release project, and have, to date, released over 130 orangutans in to the Bukit Tigapuluh landscape, a 320,000 hectare expanse of forest in Jambi and Riau provinces. This forest is extraordinarily rich in biodiversity, and hosts at least 80 mammal species, including around 30 tigers and 150 elephants, 193 species of bird, 98 species of fish and 4 species of reptile, and includes the 134,834 hectare Bukit Tigapuluh National Park. Despite a history of agricultural encroachment and logging, much of the park and greater landscape remains substantially wild. However, forest concessions to pulp and paper companies in recent years has seen massive deforestation, and recently revealed plans by these companies to convert further forest blocks on the border of the park in to plantations will directly threaten this biodiversity, and the orangutan release project (KKI Warsi, 2010).

Responding to these threats, in November 2006, OUREI organized a conference, workshop and summit, bringing all relevant stakeholders together to create a suitable education curriculum that addresses conflict between humans and orangutans in Sumatra. Working with our Indonesian partners (Sumatran Orangutan Conservation Program, Sumatran Orangutan Society, Orangutan Caring Club of North Sumatra, Fauna and Flora International, and Leuser International Foundation), we have delivered the curriculum to audiences near orangutan habitat in the provinces of North Sumatra and Aceh, explaining to local people both the importance of orangutans as a species, and the overwhelming importance of their forest home. In 2008, the program was expanded to include academic institutions and broadcast media, and the annual ‘Orangutan Caring Week’ continues to inspire young people in the Medan area of the island. The challenges facing orangutans in Sumatra have never been greater, but with continued conservation efforts, and OURF’s expanding education program, we hope that Asia’s great orange ape and its forest home can survive. EIA. (1999). The Final Cut. Environmental Investigation Agency, UK KKI Warsi.

(2010). Last chance to save Bukit Tigapuluh. WWF Robertson, Y. (2002). Briefing document on road network through the Leuser Ecosystem. Wildlife Research Group, Cambridge University, UK. Sumatran Orangutan Conservation Action Plan (2005). Workshop Report. Wich S.A., Maijaard, E., Marshall, A.J., Husson, S., Ancrenaz, M., Lacy, R.C., Van Schaik, C.P., Sugardjito, J., Simorangkir, T., Traylor-Holzer, K., Doughty, M., Supriatna, J., Dennis, R., Gumal, M., Knott, C.D. & Singleton, I. (2008). Distribution and conservation status of the orangutan on Borneo and Sumatra. How many remain?. Oryx, vol 42, issue 3, pp. 329-339 WWF. (2008). Sumatra. WWF Primate Factsheets: Orangutan (Pongo) Taxonomy, Morphology, & Ecology Species: P. abelii, P.

pygmaeus Subspecies: P. p. morio, P. p. pygmaeus, P. p. wurmbii Other names: orangoutan (French); orango (Italian); maias or mawas (Malay); orangután (Spanish); orangutang (Swedish); P. pygmaeus: Bornean orangutan; P. abelii: Sumatran orangutan Translated from Malay, orangutan means "person of the forest," but it is also used to denote a madman or savage human and is not the word for orangutan used by local people (Rijksen 1978). The Malay word for orangutan is maias or mawas (Rijksen 1993). MORPHOLOGY Genetically diverging 1.5 million years ago, phenotypic differences between the two species of orangutan are apparent. Sumatran orangutans are thinner than their Bornean relatives, have paler red coats, longer hair, and longer faces. Adult males have mustaches and prominent cheek pads, called flanges, that are covered with fine, white hair.

Both sexes have long beards (Courtenay et al. 1988; Rowe 1996). Bornean orangutans have coarse, long hair that can be orange, brown, or maroon. Infants are born with pink faces but as they age, the pigment changes to dark brown or almost black skin. Males have large, pendulous throat pouches and, compared to the Sumatran species, their cheek pads are markedly larger, covered in short bristly hair (Courtenay et al. 1988; Rowe 1996). Males and females of both species are highly sexually dimorphic , with males weighing, on average, 87 kg (192 lb) and measuring 970 mm (3.18 ft) and females weighing, on average, 37 kg (81.6 lb) and measuring 780 mm (2.56 ft) (Markham & Groves 1990; Rowe 1996).

Pongo pygmaeus Orangutans climb using both hands and both feet to hold onto branches as they move horizontally through the rain forest canopy (Rodman 1993). The position of their thumbs and big toes makes it possible to move hand over hand through the trees grasping branches with their feet as well; their fingers and toes act like hooks (Galdikas & Briggs 1999). When they move along the ground, orangutans walk quadrupedally on their fists, not their knuckles as is seen in the other great apes, and they are occasionally seen moving bipedally (Rowe 1996). Orangutans can live between 50 and 60 years in the wild (Rowe 1996). RANGE Pongo abelii | Pongo pygmaeus The two species of orangutan are geographically separated and found only on the islands of Borneo and Sumatra.

While the whole of Sumatra is part of Indonesia, the island of Borneo is divided into federal states of Malaysia (Sarawak and Sabah) and provinces of Indonesia (Kalimantan), and is partly comprised of the independent sultanate of Brunei (Kaplan & Rogers 1994). Borneo is the third largest island in the world and orangutans occur at low density in all suitable habitat in eight regions of Borneo: Sabah, Kutai region, central Borneo, Bukit Raya/Bukit Baka, Tanjung Puting, Kendawangan, Gunung Palung, and Gunung Nyuit (Rijksen et al. 1995). Orangutans are mainly found in northwestern Sumatra in the Leuser Ecosystem (formerly Gunung Leuser National Park) and the surrounding area, and may be thinly spread down the west coast of the island (van Schaik et al. 1995; Rijksen & Meijaard 1999).

Estimates of the orangutan population on Borneo suggest that there are about 55,000 in the wild, while the Sumatran orangutan is thought to number 7,000 individuals (Singleton et al. 2004). There are about 350 orangutans in captivity in the United States (Rijksen & Meijaard 1999). Studies on wild orangutans have been on-going for more than 30 years. One of the most important field sites is Tanjung Puting National Park on Borneo, made famous by Biruté Galdikas who, like Jane Goodall (chimpanzees) and Dian Fossey (gorillas), was sponsored by Louis Leakey, to study wild orangutans in the early 1970s. More than just a field study site, Galdikas established a rehabilitation center and tourist program for the area, bringing international attention to the plight of wild orangutans (Rijksen & Meijaard 1999).

Bornean orangutans are also studied at Kutai and Sebangau National Parks and Mawas Reserve in Kalimantan and at Kinibatanga in Sabah (Husson pers. comm). The Leuser Ecosystem on Sumatra has several key study sites including Suaq Balimbing, Renun, and Ketambe, though serious habitat loss has compromised research in these forests (Delgado & van Schaik 2000; Husson pers. comm.). Pioneering ecological and behavioral research on wild orangutans at the Ketambe study site in Gunung Leuser was conducted by H.D. Rijksen. HABITAT Bornean orangutans live in isolated fragments of the oldest forests on Earth in a total area of 150,000 km² (57,915 mi²) comprised of hilly or mountainous areas as well as lowland swampy areas (Kaplan & Rogers 1994; Rijksen & Meijaard 1999; Rijksen 2001).

The two major types of forest on Borneo are peat swamp forest and lowland dipterocarp forest (Rodman 1988). Dipterocarps are members of a family of trees (Dipterocarpaceae) that characterize this area of the world and are highly valued as timber resources (Kaplan & Rogers 1994). Orangutans utilize primary tropical rain forest and old secondary forest at low elevations, though they may also venture into grasslands, cultivated fields, gardens, young secondary forest, and shallow lakes (Galdikas 1988). Rainfall, averaging 4300 mm (14.1 ft) annually, is relatively uniform across the area and is heavy from December through May as well as in September, while June through August is dry. Temperatures range from 18° C (64.4° F) to 37.5° C (99.5° F) (Galdikas 1988; Knott 1998).

Orangutans on Borneo occupy all forested habitat except for northern Sarawak and Brunei and the region east of Sungai Barito and south of Sungai Mahakam. They are also thought to be restricted by elevation and are not found in forests at elevations greater than 1000 m (3281 ft) (Husson pers. comm.). Sumatran orangutans range across a total area of 26,000 km² (10,039 mi²) comprised of wide plateaus and mountainous regions, at elevations up to 1500 m (4921 ft), as well as lowland swamps at sea level (Rijksen & Meijaard 1999). They are found in lower population densities at higher elevations, and lowland dipterocarp, freshwater, and peat swamp forests are of primary importance. Annual rainfall is about 3000 mm (9.84 ft) with the wet seasons ranging from March to June and September to December.

Average annual temperature is 29.2° C (84.5° F) but ranges from 17° C (62.6° F) to 34.2° C (93.5° F) and humidity is near 100 % year-round (Rijksen 1978). ECOLOGY Pongo pygmaeus Orangutans are found in the highest densities in areas which have a mosaic of habitat types that provide high quantities of food throughout the year such as lowland swamp forests, where tree diversity is much higher, than in hilly or mountainous regions (Rodman 1988; Kaplan & Rogers 1994; Russon et al. 2001). Peat swamps support medium-densities of orangutans and they are found in the lowest densities in dipterocarp forests (Husson pers. comm.). They eat a wide variety of plant species but are mainly frugivores 61% of their diet).

They have been recorded eating buds, open flowers, young leaves, bark, sap, vines, orchids, reed roots, bird eggs, spider webs, termites, caterpillars, ants, fungi, honey, and other various plant parts (Rijksen 1978; Galdikas 1988). Extreme variability in the abundance of fruit from season to season and year to year is typical of dipterocarp rainforests. Mast fruiting occurs every two to 10 years and is a phenomenon in which large numbers of trees fruit simultaneously despite no seasonal change in temperature or rainfall (Knott 1998). During this time, orangutans engorge themselves with fruit, greatly exceeding their daily caloric intake requirements and putting on additional fat stores. In periods of high fruit abundance, males consume more calories and spend more time feeding per day than females. This propensity to overeat during times of food abundance and efficiency of storing fat reserves may be why captive orangutans often struggle with obesity (Knott 1998). When mast fruiting does not occur during a year, there is still an annual fruit peak.

Fruit is widely available during the beginning and end of the rainy season (December and May) and is scarce by the end of the dry season (August) (Galdikas 1988; Knott 1998). Fruit is always preferentially eaten, but when fruits are in short supply, orangutans forage opportunistically and depend more heavily on other plant foods such as bark, pith, leaves, flowers, and insects (Knott 1998). Sumatran orangutans heavily prefer figs over any fruits, especially Ficus species, though figs are largely unavailable to lowland ranging Bornean orangutans (Rijksen 1978; Galdikas 1988). Orangutans spend more than 95% of their daily activity budgets feeding, resting, and moving between feeding and resting sites (Rodman 1988; 1993). Their daily activity patterns show two peaks, one in the morning and another in late afternoon.

After leaving their night nest, orangutans spend two to three hours vigorously feeding in the morning, then rest during the midday hours, travel during the late afternoon, and, in the early evening, prepare their night nests (Rijksen 1978; Galdikas 1988). Day ranges vary between 90 and 3050 m (.056 and 1.90 mi), with an average of 790 m (.491 mi), though males generally travel further than females each day (Galdikas 1988). Day range length is directly proportional to home range size; orangutans with larger home ranges have larger day ranges and those with smaller ones have smaller day ranges (Rodman 1993). In the peat and lowland swamp forests of Borneo, where faunal diversity is great, home ranges for females are between 3.5 and 6 km² (1.35 and 2.32 mi²) (Galdikas 1988).

On Sumatra, where orangutans inhabit higher elevations and swamp forests with less diversity, average female home ranges tend to be larger, closer to 8.5 km² (3.28 mi²) Singleton & van Schaik 2001). There is little data on male home ranges because they are likely larger than any study sites, but it is inferred that male home ranges are several times larger than those of females, and as such are neither exclusive nor particularly stable (van Schaik & van Hooff 1996). Sumatran orangutans are subject to predation by tigers, clouded leopards, hunting dogs, and crocodiles, but tigers constitute the major predatory threat. Clouded leopards are capable of killing Sumatran orangutan adolescents and small adult females, but have not been known to kill adult males (Rijksen 1978). The presence of predators is probably the reason that Sumatran orangutans are rarely seen venturing onto the ground.

Bornean orangutans, on the other hand, are not subject to predation by large felids , and are seen more frequently on the ground than the Sumatran species (Rijksen 1978; Galdikas 1988). Content last modified: June 13, 2005 Written by Kristina Cawthon Lang . Reviewed by Simon Husson. Cite this page as: Cawthon Lang KA. 2005 June 13. Primate Factsheets: Orangutan (Pongo) Taxonomy, Morphology, & Ecology . < Accessed 2017 January 20. Orangutans | Orangutan Foundation International Orangutan Behavior Social organization, male-male competition, life history, life in the trees, nest building, tool use, culture: Orangutans are a semi-solitary species with very slow life histories. They travel, eat, and sleep in the forest canopy, making a new sleeping nest most nights. Orangutans have a high level of intelligence which manifests itself in tool-use and the making of tools in the wild.

Orangutans exhibit many socially learned traditions that are passed down from generation to generation Orangutan Biology Taxonomy, morphology, growth, evolution: There are two species of orangutans, Pongo pygmaeus in Borneo, and Pongo abelii in Sumatra. They are the largest arboreal animals in the world and their bodies are adapted to eat, sleep, and move in the forest canopy. It is probable that orangutans diverged from the human lineage between about 12 and 15 million years ago. Orangutan Ecology Geographical range, diet: Orangutans are currently found only on the islands of Borneo and Sumatra with the Sumatran species limited to the northern part of the island. Orangutans on both islands are mostly found in peat swamp forests, tropical heath forests, and mixed dipterocarp forests. Orangutans eat ripe fruit, along with young leaves, bark, flowers, honey, insects, vines, and the inner shoots of plants. Orangutan Conservation The primary factor causing the decline of orangutan populations is the destruction and degradation of their tropical rain forest habitats.

Human activities and development, such as logging, conversion of forest to palm oil plantations, mining, and urban expansion, are the major contributors to the loss of orangutan habitat. Orangutan Facts | BOS Foundation Orangutan Facts FAQ Stay Updated We need your support to preserve the orangutans and their habitat. Join our mailing list to receive regular updates and information from us. Thank you! Critically Endangered Overview The orangutan is the only member of the great ape family found in Asia. All other members of the great ape family are located in Africa; chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla and Gorilla beringei), and bonobo (Pan paniscus). There are two species of orangutan, the Bornean orangutan (Pongo pygmaeus) distributed across the island of Borneo in Indonesia (Kalimantan) and Malaysia (Sabah and Sarawak, and the Sumatran orangutan (Pongo abelii) situated on the Indonesian island of Sumatra. The two species have been geographically separated for at least 8,000 years when increased sea levels isolated the two islands.

Based on scientific research investigating genetics, morphology, ecology, behaviour and life history, Sumatran and Bornean orangutans demonstrate significant differences (Delgado & van Schaik, 2000; Groves, 2001; Zhang et al., 2001). Overall physical characteristics The Bornean orangutan (Pongo pygmaeus) has a larger body size, and has dark or reddish brown short hair; The Sumatran orangutan (Pongo abelii) has a smaller body size, with brighter orange hair In both species, male orangutans are much larger than the females, typically two to three times heavier.

Male orangutans develop large cheek pads (flanges) which develop post-sexual maturity Male orangutans develop large cheek pads (flanges) which develop post-sexual maturity Bornean Orangutan The Bornean orangutan is classified into 3 sub-species (Groves, 2001; Warren et al., 2001): Pongo pygmaeus pygmaeus, ranging from northwest Kalimantan (including Betung Kerihun and DanauSentarum National Parks) north of the Kapuas river, across the east of Sarawak state (Malaysia) Pongo pygmaeus wurmbii, ranging from south of Kapuas river in West Kalimantan to east of the Barito river in Central Kalimantan Pongo pygmaeus morio ranging throughout Sabah and East Kalimantan south to the Mahakam river. Habitat and Behaviour Bornean orangutans inhabit lowland tropical dry-land and swamp forests up to 500 m above sea-level, occasionally ranging higher or in degraded habitats. Orangutans are the largest arboreal animal, i.e.

creatures that spend most of their time in the trees and complete their life-history in the trees. However orangutans, particularly males, do spend time foraging or travelling on the ground. Orangutans build a new sleeping platform, or ‘nest’, high in the trees each night by bending branches into a bowl and filling with foliage. Diet Orangutans are predominately frugivorous, with over 100 types of fruit typically recorded in their diet from any one site. However they have a very wide diet which includes flowers, leaves, the cambium layer of bark; the inner pith of rattans, pandans, gingers and palms; termites, ants and other invertebrates; honey, fungi and on very rare occasions have been observed to eat small mammals. They need to rely on these foods during periods of fruit-shortage and also develop large fat reserves to help them through extreme periods of food shortage, or ‘fruit-crunch periods. Orangutans are important dispersal agents of fruit seeds, either by passing seeds through their digestive tract or by carrying and discarding seeds as they move through the trees, thus playing a key role in forest ecology and regeneration.

Social Behaviour Orangutans are essentially solitary with the only permanent bond being between mother and infant. However they do live in very loose clusters of related females, which occasionally meet in twos and sometimes more during periods of higher food-availability to allow bonds to be maintained, infants to play and learn together and novel behaviours to be shared. Males disperse away from their natal range to prevent inbreeding and become sexually mature at around 15 years of age. Between 18 and 20 years old they grow much larger and develop secondary sexual characteristics of cheek flanges and large throat sac, which they use to make booming long calls to attract females and warn-off other males. Males compete to become dominant, although non –dominant males do father a large proportion of infants, particularly unflanged males aged 15-20 who have not attained full size and are able to forcefully mate females. Female orangutans give birth to one infant at a time after 8 and a half months of pregnancy, and do not have another child until the first infant reaches seven years of age.

This is the longest inter-birth interval known in the animal kingdom and enables the mother to give full attention to her offspring as it learns the skills needed to survive on its own, including making nests, recognising different kinds of food and avoiding predators. Once it has learnt these skills it still stays with its mother for protection and to make a mental map of the forest, particularly to learn where all the important food resources are, until it is time to move away. Orangutans are highly intelligent creatures with advanced problem-solving skills. They are able to make use of things in their environment for tools and medicines. They display cultural behaviours, with different populations tackling the same problem in different ways. They learn from other orangutans and pass on their own skills when they meet, which is more frequent when food availability is high. In artificial circumstances where food-availability is unlimited, such as in captivity or on the BOS Foundation’s pre-release islands, they can quickly develop and share very advanced skills, such as fishing, swimming with the use of a float or tool-use to efficiently access foods.

Conservation The latest population estimate for Bornean orangutans derived at the International Population Habitat Viability Analysis (PHVA) Workshop in 2004, was approximately 55,000 individuals. At the same time it was noted that populations are decreasing at a rapid rate owing to (1) forest conversion, particularly for oil-palm plantations and other forms of agriculture; (2) other forms of forest loss, particularly forest fires in drained peatland areas; (3) forest degradation by illegal logging and (4) hunting of orangutans for food and capture for the pet-trade. Approximately one third of orangutans are found in conservation forests and the remainder are under severe threat. They are classified as Endangered by the International Union for Conservation of Nature and Natural Resources (IUCN) and protected under Indonesian Law against any kind of persecution of them or their habitat. Nevertheless forest is still being cleared, logged or burnt and this has led to the death of many thousands of orangutans over the past decade and the displacement of many more. Some of these displaced orangutans have been rescued by Reintroduction Centres that aim to return them back to the wild once safe and secure forests are identified.

2009. Orangutan Indonesia Conservation Strategies and Action Plan. The Ministry of Forestry Whats Next? Adopt Orangutan By adopting one of orangutans you help us provide the care and rehabilitation needed for orphaned orangutans to be returned to the wild Where Do Orangutans Live? And Nine Other Orangutan Facts | Stories | WWF Where Do Orangutans Live? And Nine Other Orangutan Facts Date: February 24, 2014 F 1. Where do orangutans live? Orangutans are found only in the rain forests of the Southeast Asian islands of Borneo and Sumatra. They spend nearly their entire lives in trees—swinging in tree tops and building nests for sleep. 2. Do the two species of orangutans look different from one another? The two species of orangutan, Bornean and Sumatran, differ slightly in appearance and behavior. While both have shaggy reddish fur, Sumatran orangutans have longer facial hair and seem to have closer social bonds than their Bornean cousins. Bornean orangutans are more likely to descend from trees on occasion and move around on the ground. 3.

What threats do orangutans face? Asia’s only great apes are threatened by rapid deforestation and devastation of their habitat, mainly due to palm and other agricultural plantations. Young orangutans, in particular, are also imperiled by the illegal pet trade and mothers often killed as poachers snatch their young. 4. How many orangutans are left in the wild? The Bornean orangutan is listed as Endangered and numbers approximately 41,000, while the Sumatran orangutan is considered Critically Endangered with an estimated population of 7,500. A century ago, more than 230,000 orangutans likely roamed in the wild. 5. Do orangutans stick by their young? Adult orangutans are solitary by nature but mothers stay with their young for up to eight years—longer than any other great ape. 6. What do orangutans eat? Fruit makes up about 60% of the orangutan's diet, including lychees, mangosteens, mangoes and figs. They also eat young leaves and shoots, insects, soil, tree bark, and occasionally eggs and small vertebrates.

Water comes from fruit as well as tree holes. 7. How does WWF help orangutans? WWF has been working on orangutan conservation since the 1970s. Today, we are focused on securing landscapes for major orangutan habitats, promoting sustainable forestry and stopping illegal wildlife trade. 8. Where does the word 'orangutan' come from? The name orangutan translates to 'man of the forest' in the Malay language. 9. Do orangutans climb trees? Orangutans are distinguished by their long, muscular arms and gripping hands and feet which allow the world’s largest tree-dwelling mammal to sway branch to branch. 10. How do orangutans and people live together? WWF helped launch a sustainable honey business on the island of Borneo, where orangutans and people depend on the same forests. The prized, forest-grown product provides income and deters destruction of orangutan habitat. Orangutans | WWF Orangutans Orang-utans Orang-utans are the world's largest tree-climbing mammals. But their forest habitat in Indonesia and Malaysia is rapidly disappearing, putting the future of Asia's only great ape in peril.

Subscribe to WWF Sumatran orangutan (Pongo abelii) female swinging through the trees with male baby. Gunung Leuser National Park, Sumatra, Indonesia. © naturepl.com/Anup Shah / WWF Why orang-utans matter Orang-utans are known as gardeners of the forest. They play a vital role in seed dispersal and in maintaining the health of the forest ecosystem, which is important for people and a host of other animals, including tigers, Asian elephants and Sumatran rhinos. So by conserving the orangutan’s habitat, we’re also benefiting local communities and other species. Physical description Orang-utans have a characteristic ape-like shape, shaggy reddish fur and grasping hands and feet. Their powerful arms are stronger and longer than their legs and can reach 2m in length, long enough to touch their ankles when they stand. There are two different types of adult male orang-utan: flanged and unflanged. Flanged males have prominent cheek pads called flanges and a throat sac used to make loud verbalizations called 'long calls'. They also have a long coat of dark hair on their back. The unflanged male looks like an adult female.

Both reproduce and an unflanged male can change to a flanged male for reasons that are not yet fully understood. Orang-utans are the only primate in which this biological phenomenon occurs. Male orang-utans can tip the scales at 90 kg, while females weigh between 30-50 kg. Social structure Orang-utan means 'person of the forest' in the Malay language. They live in primary and secondary forests. Although they can occur up to 1,500m above sea level, most are found in lowland areas and prefer forests in river valleys or floodplains. Orang-utans travel by moving from one tree to another, and usually avoid climbing down to the ground. But when they do, they move on 'all fours', placing their clenched fists on the ground. Orang-utans make a nest of vegetation to sleep in at night, and rest in smaller nets during the day. Adults are generally solitary, although temporary aggregations are occasionally formed. Males' large home ranges overlap with the ranges of several adult females. Adult males are generally hostile to one another, although they do not display territorially.

Life cycle Orang-utans can live up to 50 years in the wild. Females first reproduce between 10-15 years of age. They give birth at most once every 5 years, and the interval between babies can be as long as 10 years. Orang-utans usually give birth to a single young, or occasionally twins. Orang-utans stay with their mothers for the first 7-11 years of their life. An infant rides on its mother's body and sleeps in her nest until it is able to survive on its own. The long time taken to reach sexual maturity, the long interbirth periods, and the fact that orang-utans normally give birth to just a single young mean that orang-utans have an extremely low reproductive rate. This makes orang-utan populations highly vulnerable to excessive mortality, and means that populations take a long time to recover from population declines. About 60% of the orang-utan's diet includes fruit, such as durians, jackfruit, lychees, mangosteens, mangoes and figs.

The rest comprises young leaves and shoots, insects, soil, tree bark, woody lianas, and occasionally eggs and small vertebrates. They obtain water not only from fruit, but also from tree holes. Two species There are two species of orang-utan - the Bornean and Sumatran - which differ a little in appearance and behavior. While both species have shaggy reddish fur, Sumatran orangutans have longer facial hair. Sumatran orang-utans are also reported to have closer social bonds than their Bornean cousins. The Sumatran orang-utan is almost exclusively arboreal. Females virtually never travel on the ground and adult males do so only rarely. This is in contrast to Bornean orang-utans, especially adult males, which more often descend to the ground. Flanged male Bornean orangutan (Pongo pygmaeus) © David Lawson / WWF-UK 01 Dec 2016 0 comments Population & distribution Orang-utans were once distributed widely across Southeast Asia, roaming as far north as southern China, and as far south as the Indonesian island of Javar.

But today Asia's great ape is confined to just two islands, Borneo and Sumatra. As the orang-utan's range has decreased so have its numbers. A century ago, there were probably 230,000 orang-utans - around four times as many as there are today. Their dense forest home makes it difficult to determine population sizes, but the Bornean orang-utan is estimated to number around 54,000 individuals, while there are around 6,600 Sumatran orang-utans. The Sumatran orang-utan is now restricted to the north of Sumatra. It depends on high-quality primary forests, and is less able to tolerate habitat disturbance than Bornean orang-utans. Sumatran orang-utan densities reportedly fall by up to 60% with even selective logging. The population is currently fragmented into 13 populations in 21 forest blocks. Only 6 of these populations boast more than 250 animals and are therefore regarded as viable in the long term, but even these groups are under threat due to ongoing habitat loss.

The Bornean orang-utan was once distributed throughout large areas of Kalimantan (Indonesia) and Sarawak and Sabah (Malaysia) on the island of Borneo. But its population has fallen by more than 50% over the past 60 years, while at least 55% of its habitat has disappeared over the last 20 years. Most Bornean orang-utans are now found in Kalimantan, especially along the east coast. The majority of wild populations are located outside of protected areas, in forests that are exploited for timber production or are in the process of being converted to agriculture. Three subspecies live in different parts of the island: Northwest Bornean orang-utan is the most threatened subspecies with over 3,000 remaining. Northeast Bornean orang-utans are the smallest in size. Around 16,000 live in Sabah and parts of eastern Kalimantan. Central Bornean orang-utans are the most common subspecies with around 35,000 surviving. What are the main threats? Habitat loss is by far the greatest threat to orang-utans.

Huge tracts of forest have been cleared throughout their range and the land used for agriculture, particularly palm oil - a product that is found in more than half of packaged products in supermarkets around the world. Road development, illegal timber harvesting and unsustainable logging, mining and human encroachment also contribute to habitat loss, degradation and fragmentation. Today, more than 50% of orang-utans are found outside of protected areas, in forests under management by timber, palm oil and mining companies. But even protected areas are not secure since the boundaries of protected areas in Borneo are often not clearly delineated, which makes them difficult to patrol. Furthermore, many parks are understaffed and underfunded. Consequently, oil palm companies and logging firms have encroached into all the parks. Along with habitat loss, young orang-utans up to the age of seven are sought after for the illegal pet trade. When infants are targeted, usually the mother is killed so this trade represents a real threat to wild orang-utan populations. In addition, orang-utans are hunted in some areas for food. They are also sometimes killed when they move into agricultural areas and destroy crops. And fire is also a major threat.

In 1997-98, the drainage of peat-swamp forest contributed to uncontrollable fires in Kalimantan, which lasted for 6 months and killed up to 8,000 orang-utans. Distribution of Sumatran orangutan, Sumatra, Indonesia. Map created by Ian Singleton with Riswan and Rachmadi A. Dadi. Source: Singleton, I., S. Wich, S. Husson, S. Stephens, S. Utami Atmoko, M. Leighton, N. Rosen, K. Traylor-Holzer, R. Lacy and O. Byers (eds.). 2004. Orangutan Population and Habitat Viability Assessment: Final Report. IUCN/SSC Conservation Breeding Specialist Group. © Ian Singleton with Riswan and Rachmadi A. Dadi. Data from: Ancrenaz, M. and Lackman-Ancrenaz, I. 2004. Orangutan status in Sabah: distribution and population size; Meijaard, E. and Dennis, R. 2003.

Assessment of the extent of remaining habitat for Bornean Orangutan, based on 2002 forest cover data. © In: Singleton, I., S. Wich, S. Husson, S. Stephens, S. Utami Atmoko, M. Leighton, N. Rosen, K. Traylor-Holzer, R. Lacy and O. Byers (eds.). 2004. Orangutan Population and Habitat Viability Assessment: Final Report. IUCN/SSC Conservation Breeding Specialist Group. Loggers clearing a swamp forest for a palm oil plantation. (Illegal logging) Central Kalimantan, Indonesia. © Alain COMPOST / WWF

Question: The orangutan is found on Sumatra and which other island?
Answer: Borneo