In 1970, an agreement was made between the Indonesian Nature Conservation Service (then the PPA, now the PHKA), The Netherlands Gunung Leuser Committee, and the World Wildlife Fund, to enhance the conservation and management of what was then a complex of interconnected forest reserves, simply referred to as the Gunung Leuser Reserves. This series of reserves would eventually come to be known worldwide as the Gunung Leuser National Park, and the more expansive Leuser Ecosystem conservation area. As a part of this initial agreement, the Ketambe monitoring station, located in the upper Alas River valley of the Leuser Ecosystem, was first established in 1971 by Dr. Herman Rijksen. At Ketambe, with financial support from the Netherlands Foundation for the Advancement of Tropical Research and the Netherlands Appeal of the World Wildlife Foundation, Herman helped develop a rehabilitation station for illegally captured orangutans (1971-1974), in addition to one of the longest running primate field studies of our time.

Ketambe has been a springboard for many well-known orangutan field researchers, including Dr. Chris Schrümann (1975-1979), Dr. Carel van Schaik (1979-1984), Dr. Maria van Noordwijk (1979-1984), Dr. Jito Sugardjito (1979-1983), Dr. Tatang Mitra Setia (1991-1993), Dr. Serge Wich (1993-1995, 1998-2000), and Dr. Sri Suci Utami Atmoko (1993-1996), in addition to a countless number of other field researchers and students who have come and studied there over the years. The relatively uninterrupted and continued presence of field researchers at the Ketambe monitoring station, beginning with Herman’s pioneering work in the 1970’s, places it in a league with some of the most long-term and well-known great ape field projects ever established, including, Budongo Conservation Field Station in Uganda (chimpanzees), Gombe Stream Research Center in Tanzania (chimpanzees), Karisoke Research Center in Rwanda (mountain gorillas), Mahale Mountains Research Project in Tanzania (chimpanzees), Camp Leakey in Central Kalimantan (Bornean orangutans), and Wamba Research Station in the Democratic Republic of Congo (bonobos).

Due to its long-term nature, Ketambe has uniquely provided both the public and scientific communities with a comprehensive and detailed wealth of information about Sumatran orangutans and their behavioral ecology. Most importantly, long-term studies such as those at Ketambe are vital to understanding the adaptive strategies, life history variables, and social behavior of an animal population, especially in long-lived slowly maturing species, such as the Sumatran orangutan. As such, these long-term data are also vital to conservation biologists, who are currently working to establish effective and sustainable conservation strategies.

Ketambe owes much of its continued success to numerous collaborating institutions and universities, such as the Indonesian Nature Conservation Service (PHKA), the World Wildlife Fund, the Netherlands Foundation for the Advancement of Tropical Research, the Leuser Development Programme, the Leuser Management Unit, Utrecht University (Utrecht, Netherlands), and Universitas Nasional (Jakarta, Indonesia), which in one way or another have been sources for funding, management assistance, and/or professional researchers, since its inception in 1971.

Despite this long list of successes, Ketambe has also had its share of setbacks. For instance, at the end of 1999, with the onset of civil unrest in Aceh, the future of Ketambe and its long-term project was uncertain, and as no new research permits could be granted during the conflict, research ceased completely in early 2002. Fortunately, however, SOCP working together with local and international scientists, in addition to the local management authorities, succeeded in resuming data collection in mid-2003. Unfortunately, at the end of 2011, as a result of conflicts between local management authorities, all SOCP monitoring activities at Ketambe were put on hold. Nevertheless, during this period (2003-2011), SOCP helped facilitate research for three PhD projects, six master’s projects, and 10 bachelor’s projects.

Currently, the SOCP is working diligently, in collaboration with the PanEco Foundation and Yayasan Ekosistem Lestari, to re-open the Ketambe monitoring station, so that both local and international researchers may continue the excellent tradition started by Herman in the 1970’s. SOCP’s presence at Ketambe is not only imperative for its unique long-term orangutan database, but it also serves as a major deterrent for the many illegal human extractive industries that plague Indonesia. As such, we at SOCP hope that in the near future we can again make Ketambe a leading project in the fight to conserve Sumatran orangutans and their remaining forest habitat.


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To counteract the explosive extinction of the Sumatran rainforest, the Orangutan Coffee Project supports coffee farmers in the highland of Gayo, Aceh province to manage their plantations in an ecological and sustainable way.


Special premiums from Orangutan Coffee trade reward both local coffee farmers and also support the Sumatran Orangutan Conservation Programme.

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