Prey Lang Wildlife Sanctuary

The largest lowland evergreen forest remaining in mainland Southeast Asia and Cambodia’s largest protected area


Conservation International is working to protect this critical forest for people, nature and climate in Southeast Asia.

Conservation International has been researching Prey Lang to better understand its ecological value since 2005. Our science helped define the boundaries of this protected area, Cambodia’s largest. Now, we are helping communities establish sustainable rice production to provide a source of income in exchange for environmental protection. In addition, we are developing a carbon project to ensure sustainable financing is available to protect the Prey Lang forest for the benefit of all.


Why is it important?

Prey Lang is one of the most biodiverse forests in Cambodia, and more than 250,000 people live in and around the protected area. Most of them rely directly on the habitat for their subsistence and livelihoods.


This forest is one of the largest remaining in the region. It includes a variety of habitats, from rainforest to grasslands to marshes.



Prey Lang provides critical refuge to 55 threatened species, including gibbons, Asian elephants and nearly 45 percent of all of Cambodia’s bird species and one-third of the country’s bat species. It is home to 538 plant species and 80 percent of the most endangered Indigenous tree species in Cambodia.


Watershed protection

Prey Lang provides water to the Stung Sen and Stung Chinit rivers. Both flow into Cambodia’s Tonle Sap Lake, home to one of the world's largest freshwater fisheries, which is essential to the country’s economy and food security.


What are the issues?

© Leah Duran/Conservation International

Illegal logging and mining

Despite the forest’s protected status, illegal logging continues at an alarming rate. Many of the most prized timber species, such as rosewood, are already very scarce, and loggers have begun to remove other valuable species.


© Jeremy Holden

Wildlife trade

Hunting, especially with wire snares, is the biggest threat to biodiversity in Southeast Asia. Unfortunately, the illegal wildlife trade is flourishing in Prey Lang. Many mammals, lizards, birds and reptiles caught in Prey Lang are sold in local markets or exported to China and Vietnam.


A Cambodian farmer works on a rice field in Phnom Penh, Cambodia.
© EPA/How Hwee Young/Alamy Stock Photo


Prey Lang’s forests are under intense pressure from agriculture, the primary livelihood in the area. Logging for domestic purposes remains largely unregulated. Meanwhile, new roads are cutting into sensitive areas, breaking up habitats and facilitating access for illegal logging and poaching.


© Aya Uraguchi


The forests of Prey Lang store an estimated 120 million tons of climate-warming carbon. This is roughly equivalent to the annual carbon emissions from 26 million cars. Deforestation releases this carbon into the atmosphere.


Our plan

Prey Lang Wildlife Sanctuary is the largest lowland evergreen forest in mainland South East Asia, Cambodia’s largest protected area, and recognized as one of the most biodiverse forests in the country. Over 250,000 people live in and around the sanctuary and almost all rely directly on this nature for subsistence and livelihoods. However this vital forest is under significant pressure from human activity. Conservation International have been researching Prey Lang since 2005 and are now working directly with communities, the private sector and government to improve law enforcement, establish sustainable livelihoods, and implement sustainable financing solutions based on forest carbon. Learn more at

Protected area management

Conservation International has been working in Prey Lang since 2005. To support the designation of this area as a legally protected wildlife sanctuary, we worked with various levels of government to help define the sanctuary’s boundaries across four provinces. These were formalized in 2016, becoming the nation’s largest protected area. Currently, we are partnering on the USAID-funded Greening Prey Lang project to enhance biodiversity conservation, improve protected area management and provide sustainable financing for this protected area.


© Kristin Harrison & Jeremy Ginsberg

Carbon for communities

Together with our partners, the Cambodian Ministry of Environment and the Japanese company Mitsui and Co., we are implementing a carbon project to reduce greenhouse gas emissions by protecting the Prey Lang forest, and improving livelihoods and law enforcement practices. As a part of this REDD+ project (Reducing Emissions from Deforestation and forest Degradation) we've helped to quantify forest carbon stocks, provided training to local and provincial governments to monitor the tropical forest, and provided support for improving livelihoods and law enforcement training. Through the sale of these carbon credits we aim to finance long-term forest protection.


© Karun Albert Khouth

Improving community livelihoods

Conservation International helps communities in the Prey Lang protected area establish alternative, forest-friendly sources of income in exchange for environmental protection.

Through the Ibis Rice program, we are working to improve local communities' livelihoods in partnership with the local nonprofit group Sansom Mlup Prey. Farmers receive a premium for their rice by following organic and sustainable practices.


© Jeremy Holden

Non-timber forest products

Many communities collect and sell resin, honey, rattan, bamboo and wild fruits directly from the forest. Conservation International has delivered training to support these sustainable activities. Still, more work is needed to connect these communities to markets.