# Orangutan — Facts, Threats & Conservation

*Pongo pygmaeus (Linnaeus, 1760), Pongo abelii (Lesson, 1827), Pongo tapanuliensis (Nurcahyo, Meijaard et al., 2017)*

> Orangutans are Critically Endangered great apes found only in Borneo and Sumatra; all three species — Bornean, Sumatran, and Tapanuli — face extinction driven mainly by habitat loss from palm oil and logging, plus the illegal pet trade.

**IUCN status:** Critically Endangered  ·  **WARN range:** Indonesia, Malaysia

## Quick facts
| Fact | Value |
| --- | --- |
| Lifespan | ~30–45 years in the wild; up to 50–60 years in human care |
| Weight | Males up to ~90 kg in the wild (more in captivity); females ~37–50 kg |
| Height / arm span | Standing height ~1.2–1.4 m; arm span up to ~2 m (longer than the body) |
| Diet | Frugivore — mostly fruit, plus leaves, bark, flowers, honey, and insects |
| Gestation | ~8 months (about 227–275 days) |
| Young per birth | Single infant; ~7.6–8 years between births (longest of any primate) |
| Maturity | Infants depend on the mother ~7–8 years; females mature at ~12–15 years |
| Social structure | Semi-solitary — the least social great ape; no true 'group' |
| DNA shared with humans | About 96.4% |
| CITES | Appendix I (all Pongo species) |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Primates
- **Family:** Hominidae (great apes)
- **Genus:** Pongo
- **Species:** 3 species: P. pygmaeus (Linnaeus, 1760), P. abelii (Lesson, 1827), P. tapanuliensis (Nater, Nurcahyo, Meijaard et al., 2017)

## Conservation status
- **Status:** Critically Endangered (all three species: P. pygmaeus, P. abelii, P. tapanuliensis)
- **Population:** Bornean ~104,700 (2016); Sumatran ~14,470 (2017); Tapanuli fewer than 800
- **Trend:** Decreasing
- **Assessed:** 2016 (Bornean and Sumatran); 2017 (Tapanuli, on description)
- **CITES:** Appendix I
- The Bornean population has fallen an estimated ~86% across three generations; the Tapanuli, described only in 2017, is the rarest great ape on Earth.

## Key facts: Orangutan
- Three species: Bornean (Pongo pygmaeus), Sumatran (Pongo abelii), and Tapanuli (Pongo tapanuliensis) — all Critically Endangered with a decreasing trend.
- The Tapanuli orangutan, formally described as a separate species in 2017, numbers fewer than 800 individuals, making it the rarest great ape on Earth and the most recently described.
- Females give birth roughly once every 7.6–8 years on average — the longest interbirth interval of any primate, so populations recover extremely slowly.
- Orangutans are the only great apes native to Asia and the largest tree-dwelling (arboreal) mammals on the planet.
- Conservation groups estimate that over 80% of suitable orangutan habitat has been lost in the past two decades; the IUCN documents an ~86% decline in the Bornean population across three generations.
- Orphaned infants found clinging to killed mothers are sold into the illegal pet trade or rescued and taken to rehabilitation centres, where full rehabilitation to soft release can take 5–10 years of specialised forest-school training.

## Why Are Orangutans Endangered?
The principal driver of orangutan decline is habitat loss. Lowland rainforest — where orangutans feed, nest, and raise young — is cleared for palm oil, pulpwood, and mining concessions at a pace that far outstrips population recovery. A female orangutan produces only four or five offspring in her entire lifetime, because she gives birth roughly once every eight years, the longest interbirth interval of any primate. When a forest block is cleared and breeding females are killed, a local population can be functionally destroyed within one generation. Hunting, snaring, and the illegal pet trade compound the pressure: infants are captured live when their mothers are killed, then sold as status pets or arriving at rescue centres in severe distress.

## What Does Orangutan Rehabilitation Involve?
Rehabilitation is a multi-year process that mirrors the long natural dependency of a wild infant, which stays with its mother for seven to eight years. Orphaned infants need round-the-clock medical care, then surrogate carers who teach the basics of forest life. Forest school — structured climbing, foraging, and nest-building sessions — must run daily for years. Before any release attempt, juveniles undergo a pre-release island phase to test their skills in a semi-wild environment. After soft release into a protected forest, rangers monitor individuals for up to two years. The entire process costs thousands of pounds per animal and requires purpose-built facilities that are consistently oversubscribed.

## The Palm Oil Connection
Palm oil is found in roughly half of all packaged supermarket products — from biscuits to shampoo. Global demand for cheap vegetable oil has driven the conversion of millions of hectares of Bornean and Sumatran rainforest into monoculture plantations. Certified sustainable palm oil schemes exist, but enforcement is patchy and deforestation continues, so certification alone does not guarantee a deforestation-free supply chain. Consumer awareness — and pressure on supply chains — is one lever. Expanding the rescue and sanctuary infrastructure to absorb displaced animals is another. WARN focuses on the second.

## Where Do Orangutans Live?
Orangutans survive in just two places on Earth. The Bornean orangutan ranges across the island of Borneo — the Indonesian provinces of Kalimantan and the Malaysian states of Sabah and Sarawak. The Sumatran orangutan is confined to the northern tip of Sumatra, mainly Aceh and North Sumatra, while the Tapanuli orangutan survives only in the isolated Batang Toru forest of North Sumatra. All are dependent on tropical lowland and hill rainforest, the same forests being cleared fastest for plantation agriculture.

## Bornean vs Sumatran vs Tapanuli orangutan
| Attribute | Bornean | Sumatran | Tapanuli |
| --- | --- | --- | --- |
| Species | Pongo pygmaeus | Pongo abelii | Pongo tapanuliensis |
| Described | Linnaeus, 1760 | Lesson, 1827 | 2017 (most recent great ape) |
| Range | Borneo (Kalimantan, Sabah, Sarawak) | Northern Sumatra (Aceh, North Sumatra) | Batang Toru forest, North Sumatra |
| Population | ~104,700 (2016) | ~14,470 (2017) | Fewer than 800 |
| IUCN status | Critically Endangered | Critically Endangered | Critically Endangered |
| Notable feature | Most numerous; darker, broader face | Lighter coat; longer facial hair | Frizzier coat, smaller skull; rarest great ape |

## What WARN does
WARN partners with vetted rehabilitation centres in Indonesia and Malaysia to fund expanded nursery capacity, forest-school programmes, and post-release monitoring. We also support sanctuary land acquisition to provide permanent homes for orangutans who cannot be released back into the wild.

A wild female orangutan raises only four or five young in her whole life, and a rescued orphan needs years of forest school before it can go home. Your gift helps fund the nursery care, forest-school training, and post-release monitoring that our rehabilitation partners in Indonesia and Malaysia provide for one orphaned orangutan on its multi-year journey back to the wild.

## Frequently asked questions: Orangutan
### How many orangutans are left in the wild?
The most recent IUCN Red List assessments put the Bornean orangutan at around 104,700 (last assessed 2016), the Sumatran orangutan at around 14,470 (assessed 2017), and the Tapanuli orangutan at fewer than 800 (described and assessed in 2017). All three are listed as Critically Endangered, and all show a decreasing trend — a collapse from historical population sizes.

### Why are orangutans called the "gardeners of the forest"?
Orangutans swallow and disperse large seeds across long distances as they travel and feed, making them a keystone species for forest regeneration. When they disappear from a forest, plant diversity declines and the ecosystem becomes less resilient.

### Can all rescued orangutans be returned to the wild?
Not always. Orangutans rescued as very young infants, or those kept as pets for years, may have lost the ability to survive independently and require lifetime sanctuary care. Those rescued young enough and rehabilitated fully can be soft-released into protected forest with monitoring support.

### What is the Tapanuli orangutan?
The Tapanuli orangutan (Pongo tapanuliensis) was only formally described as a distinct species in 2017, making it the most recently recognised great ape. It is found only in the Batang Toru forest of North Sumatra and numbers fewer than 800 individuals — making it the rarest great ape on Earth.

### Does buying sustainable palm oil help orangutans?
Certified sustainable palm oil can reduce pressure on forests, but certification does not guarantee that no deforestation occurred. The most effective consumer action is to push brands toward stricter no-deforestation commitments while also supporting rescue and rehabilitation infrastructure for displaced animals.

### What do orangutans eat?
Orangutans are frugivores: fruit makes up the bulk of their diet — roughly 60% of foraging time — supplemented by leaves, bark, flowers, honey, and insects. Because they swallow and scatter large seeds across the forest, they are vital seed dispersers.

### How long do orangutans live, and how big do they get?
Wild orangutans typically live around 30–45 years, and individuals in human care can reach 50–60 years. Males are about twice the size of females, reaching roughly 90 kg in the wild (more in captivity) versus around 37–50 kg for females, with an arm span that can reach about 2 metres — longer than their standing height.

### Do orangutans live in groups?
No. Orangutans are the most solitary of the great apes. Adult males are largely solitary, and females are usually accompanied only by their dependent young, so they do not form the cohesive social groups seen in chimpanzees or gorillas.

## Sources
- [IUCN Red List — Bornean Orangutan (Pongo pygmaeus)](https://www.iucnredlist.org/species/17975/17966347)
- [IUCN Red List — Sumatran Orangutan (Pongo abelii)](https://www.iucnredlist.org/species/121097935/123797627)
- [IUCN Red List — Tapanuli Orangutan (Pongo tapanuliensis)](https://www.iucnredlist.org/species/120588639/120588662)
- [CITES Appendices (Pongo spp., Appendix I)](https://cites.org/eng/app/appendices.php)
- [Smithsonian's National Zoo — Orangutan fact sheet](https://nationalzoo.si.edu/animals/orangutan)
- [WWF — Orangutan](https://www.worldwildlife.org/species/orangutan)
- [Nater et al. 2017, Current Biology — Pongo tapanuliensis description](https://www.cell.com/current-biology/fulltext/S0960-9822(17)31245-1)
- [van Noordwijk et al. 2018, 'The slow ape' (PubMed)](https://pubmed.ncbi.nlm.nih.gov/30502896/)

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Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/orangutan