Borneo and Sumatra


The forests of Borneo and Sumatra are among the most biologically diverse habitats on Earth, possessing staggeringly high numbers of unique plants and animals.

  • Continent
  • Species
    Orangutan, Sumatran rhino, Bornean elephant, Sumatran tiger, Sumatran elephant

The Southeast Asian islands of Borneo and Sumatra, located on the Equator, are home to some of the world’s most diverse rain forests and Southeast Asia’s last intact forests. Borneo is the world’s third largest island, covering an area slightly larger than Texas. Sumatra is the world’s sixth largest island. The islands’ tropical climate and diverse ecoregions have created habitats that house thousands of unique species and the world’s last remaining Sumatran tigers, orangutans, Bornean elephants, and Sumatran rhinos. Massive rivers cut across the landscape. These are the islands’ lifelines, offering transport and providing the freshwater needs for the islands’ people.

An iconic forest, protected and returning

Between 1985 and 2014, a wide swath of Sumatra’s forested land—called Bukit Tigapuluh or Thirty Hills—lost 32% of its forest cover because of deforestation.
Orangutan hanging in tree


Bornean Elephant

A Bornean elephant

Sumatra is the only place on Earth where tigers, rhinos, orangutans, and elephants live together. The forests of Borneo and Sumatra are home to marvelous creatures like the proboscis monkey, sun bear, clouded leopard, and flying fox bat, and endangered animals like the Sumatran tiger, Sumatran rhino, and Bornean elephant.

There are more than 15,000 known plants here, with many more species yet to be discovered. Since 1995, more than 400 species have been identified on the islands, with more than 50 of these species completely new to science. An unknown mammal species—for now dubbed the Bornean red carnivore—was photographed by one of WWF’s camera traps in 2003.

People & Communities

Borneo and Sumatra kayak

Local people commute using small boats in West Kalimantan, Indonesia.

The cultural diversity of Borneo and Sumatra is as distinct and varied as its plant life. More than 60 million people live on these two islands. They are a mix of indigenous peoples and immigrants from other islands in Indonesia, such as Java, as well as other Asian countries. The current population of Borneo is estimated at 18 million. Sumatra is home to 50 million people and is the world's fourth most populous island.

Rapid economic changes have brought shifts in population and threaten the way of life for communities who have traditionally lived off the forest. Borneo's native cultures are usually referred to collectively as "Dayak," a term that covers a multitude of ethnic groups. Sumatra is also home to a variety of ethnic groups, including the Batak, Minangkabau, Krui, and Pelalawan-Petalangan.


Borneo and Sumatra - Deforestation in Riau

Smoke preventing a clear view of the remaining burnt down peat forest in Riau, Indonesia.

In Borneo and Sumatra, the vast wealth of natural resources has attracted large-scale international financing focused on extractive industries, from precious hardwoods and minerals to palm oil, rubber, and coal.

Illegal Wildlife Trade

Wildlife trade is a major problem in this region. Rampant poaching, facilitated by the growing number of roads and logging trails, poses a grave threat to Borneo and Sumatra's endangered species like tigers and rhinos.

Unsustainable Agriculture

Expanding oil palm plantations and, in Sumatra, coffee cultivation is encroaching on landscapes crucial to species conservation.


Indonesia is home to approximately three percent of the world's forests. Yet deforestation in this region represents over a third of the total global carbon emissions from deforestation and land degradation. Heavy demand for plywood, hardwoods, and wood products for the pulp and paper industry leads to both legal and illegal logging.

What WWF Is Doing

Borneo and Sumatra

This dense forest landscape of the northeast tip of Borneo is home to the Bornean elephant.

In Borneo and Sumatra WWF works with local communities and governments and uses global action to address the relentless forces that are destroying the last strongholds of elephants, orangutans, and other species. 

Protecting the Heart of Borneo

WWF is implementing a collaborative conservation plan with the governments of Brunei Darussalam, Indonesia, and Malaysia to protect the Heart of Borneo—a pristine area of equatorial rain forests larger than Kansas.

Borneo and Sumatra - Orangutan

Safeguarding Sumatra’s Species

WWF collaborates with local communities, industry, and governments to alleviate human-wildlife conflict by improving enforcement and providing alternate income opportunities for local people.

Enabling Responsible Forestry

Approximately three-quarters of Indonesia’s timber is illegally harvested. WWF assists producers and traders, educates consumers, and works with partners to enable responsible forestry and restore local communities.

Practicing Sustainable Agriculture

Palm oil coming from Borneo and Sumatra accounts for more than half of all palm oil produced in the world. WWF co-founded the Roundtable on Sustainable Palm Oil in 2003, a collaborative group working to bring sustainable palm oil to the marketplace and reform land use practices.

Providing Transparency

Deforestation in Indonesia is often driven by indiscriminate land-grabbing, corruption and lack of law enforcement. WWF co-founded Eyes on the Forest (EoF) — an alliance that includes WWF, Friends of the Earth and the Forest Rescue Network Riau — to monitor the status of the remaining natural forests in Sumatra's province of Riau and share information worldwide to empower those working to protect critical habitat.


  • Thirty Hills

    WWF and partners are securing protection for a critical rain forest in Sumatra. Thirty Hills is one of the last places on Earth where elephants, tigers, and orangutans coexist in the wild.

  • The Natural Capital Project

    Centered at Stanford University, the Natural Capital Project is a partnership among WWF, Stanford, University of Minnesota, The Nature Conservancy, Chinese Academy of Sciences, and Stockholm Resilience Centre. Through pioneering science, cutting-edge technology, and collaborative partnerships worldwide, the Natural Capital Project works to integrate the value nature provides to people into all major decisions.

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